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  • 1.
    Botero, Carlos Alberto
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Jiménez-Piqué, Emilio
    Universitat Politècnica de Catalunya, Barcelona, Spain.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Microstructure and nanomechanical behavior of modified 316L-based materials fabricated using EBM2018Conference paper (Refereed)
    Abstract [en]

    Stainless steel 316L based materials modified by the additions of iron-based wear-resistant alloys (Colferoloy@ 103 and 139) used for thermal spray coatings applications were fabricated by EBM. Process parameters were tailored to fabricate compact specimens of 1cm3 in an Arcam A2 (Arcam AB, Mölndal, Sweden) at Mid Sweden University. Microstructural features of the materials obtained were characterized by OM and SEM in polished and etched samples. Nanoindentation tests carried out at different penetration depths were performed on selected areas of the polished specimens to evaluate the materials micro/nano mechanical behavior and to establish correlations with the observed microstructure.

  • 2.
    Botero, Carlos
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Roos, Stefan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Åsvik, Kenneth
    Uddeholms AB.
    Şelte, A
    Uddeholms AB.
    Ramsperger, Markus
    Arcam AB.
    Additive Manufacturing of a cold work steel using Electron Beam Melting2019In: Proceedings of Conference:  Tooling 2019, 2019, Vol. MayConference paper (Refereed)
  • 3.
    Botero Vega, Carlos Alberto
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Jiménez-Piqué, Emilio
    Universitat Politècnica de Catalunya, Barcelona.
    Roos, Stefan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Nanoindentation: a suitable tool in metal Additive Manufacturing2018Conference paper (Refereed)
  • 4.
    Botero Vega, Carlos Alberto
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Ramsperger, Markus
    Arcam AB, Mölnlycke.
    Selte, Aydin
    Uddeholms AB, Hagfors.
    Åsvik, Kenneth
    Uddeholms AB, Hagfors.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Roos, Stefan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Additive Manufacturing of a Cold-Work Tool Steel using Electron Beam Melting2019In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, p. 1-6, article id 1900448Article in journal (Refereed)
    Abstract [en]

    Metal additive manufacturing (AM) is on its way to industrialization. One of the most promising techniques within this field, electron beam melting (EBM), is nowadays used mostly for the fabrication of high‐performance Ti‐based alloy components for the aerospace and medical industry. Among the industrial applications envisioned for the future of EBM, the fabrication of high carbon steels for the tooling industry is of great interest. In this context, the process windows for dense and crack‐free specimens for a highly alloyed (Cr–Mo–V) cold‐work steel powder are presented in this article. High‐solidification rates during EBM processing lead to very fine and homogeneous microstructures. The influence of process parameters on the resulting microstructure and the chemical composition is investigated. In addition, preliminary results show very promising mechanical properties regarding the as‐built and heat‐treated microstructure of the obtained material.

  • 5.
    Chudinova, E.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Surmeneva, M.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Loza, K.
    University of Duisburg-Essen, Essen, Germany.
    Prymak, O.
    University of Duisburg-Essen, Essen, Germany.
    Epple, M.
    University of Duisburg-Essen, Essen, Germany.
    Surmenev, R.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Surface modification of Ti6Al4V alloy scaffolds manufactured by electron beam melting2019In: / [ed] Godymchuk A.,Rieznichenko L.,Semenov M., Institute of Physics Publishing (IOPP), 2019, no 1Conference paper (Refereed)
    Abstract [en]

    In this paper, the results of the surface functionalization of the Ti6Al4V alloy scaffolds with different structures for use as a material for medical implants are presented. Radio frequency magnetron sputtering was used to modify the surface of the porous structures by deposition of the biocompatible hydroxyapatite (HA) coating with the thickness of 86050 nm. The surface morphology, elemental and phase composition of the HA-coated scaffolds were studied. According to energy-dispersive X-ray spectroscopy, the stoichiometric ratio of Ca/P for flat, orthorhombic and cubic scaffolds is 1.65, 1.60, 1.53, respectively, which is close to that of stoichiometric ratio for HA (Ca/P = 1.67). It was revealed that this method of deposition makes it possible to obtain the homogeneous crystalline coating both on the dense sample and in the case of scaffolds of complex geometry with different lattice cell structure. 

  • 6.
    Chudinova, E.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Surmeneva, M.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Sokolova, V.
    University of Duisburg-Essen, Essen, Germany.
    Prymak, O.
    University of Duisburg-Essen, Essen, Germany.
    Bouckercha, S.
    University of Duisburg-Essen, Essen, Germany.
    Epple, M.
    University of Duisburg-Essen, Essen, Germany.
    Surmenev, R.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Determination of the properties and loading efficiency of encapsulated BSA-FITC and dexamethasone for drug delivery systems2019In: IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing (IOPP), 2019, Vol. 597, no 1, article id 012056Conference paper (Refereed)
    Abstract [en]

    In this work porous microparticles of calcium carbonate were synthesized with bovine serum albumin - fluorescein isothiocyanate conjugate (BSA-FITC) and dexamethasone, and then used for encapsulation in polymer microcapsules by means of layer-by-layer assembly (LbL). The properties of the obtained microcapsules were characterized by scanning electron microscopy, dynamic light scattering, infrared-, ultraviolet- and visible spectroscopy. According to the performed DLS measurements, an average hydrodynamic diameter ranged from 4 to 8 m and zeta-potential for all types of capsules was determined as -18 and -21 mV. BSA-FITC was encapsulated using this approach yielded a loading efficiency of 49 % protein. This value calculated for dexamethasone was of 38%. The microcapsules filled with an encapsulated drug may find applications in the field of biotechnology, biochemistry, and medicine. 

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  • 7.
    Chudinova, Ekaterina A.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Surmeneva, Maria A.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Timin, Alexander S.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation; First I. P. Pavlov State Medical University of St. Petersburg, St. Petersburg, Russian Federation.
    Karpov, Timofey E.
    Peter The Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation.
    Wittmar, Alexandra
    University of Duisburg-Essen, Essen, Germany.
    Ulbricht, Mathias
    University of Duisburg-Essen, Essen, Germany.
    Ivanova, Anna
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Loza, Kateryna
    University of Duisburg-Essen, Essen, Germany.
    Prymak, Oleg
    University of Duisburg-Essen, Essen, Germany.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Epple, Matthias
    University of Duisburg-Essen, Essen, Germany.
    Surmenev, Roman A.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Adhesion, proliferation, and osteogenic differentiation of human mesenchymal stem cells on additively manufactured Ti6Al4V alloy scaffolds modified with calcium phosphate nanoparticles2019In: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 176, p. 130-139Article in journal (Refereed)
    Abstract [en]

    In the present study, biocomposites based on 3D porous additively manufactured Ti6Al4V (Ti64) scaffolds modified with biocompatible calcium phosphate nanoparticles (CaPNPs) were investigated. Ti64 scaffolds were manufactured via electron beam melting technology using an Arcam machine. Electrophoretic deposition was used to modify the scaffolds with CaPNPs, which were synthesized by precipitation in the presence of polyethyleneimine (PEI). Dynamic light scattering revealed that the CaP/PEI nanoparticles had an average size of 46 ± 18 nm and a zeta potential of +22 ± 9 mV. Scanning electron microscopy (SEM) revealed that the obtained spherical CaPNPs had an average diameter of approximately 90 nm. The titanium-based scaffolds coated with CaPNPs exhibited improved hydrophilic surface properties, with a water contact angle below 5°. Cultivation of human mesenchymal stem cells (hMSCs) on the CaPNPs-coated Ti64 scaffolds indicated that the improved hydrophilicity was beneficial for the attachment and growth of cells in vitro. The Ti6Al4V/CaPNPs scaffold supported an increase in the alkaline phosphatase (ALP) activity of cells. In addition to the favourable cell proliferation and differentiation, Ti6Al4V/CaPNPs scaffolds displayed increased mineralization compared to non-coated Ti6Al4V scaffolds. Thus, the developed composite 3D scaffolds of Ti6Al4V functionalized with CaPNPs are promising materials for different applications related to bone repair. 

  • 8.
    Chudinova, Ekaterina
    et al.
    Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, Maria
    Tomsk Polytechnic University, Tomsk, Russia.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Selezneva, Irina
    Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Puschino.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Syrtanov, M
    Tomsk Polytechnic University, Tomsk, Russia.
    Surmenev, Roman
    Tomsk Polytechnic University, Tomsk, Russia.
    In Vitro Assessment of Hydroxyapatite Coating on the Surface of Additive Manufactured Ti6Al4V Scaffolds2017In: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 879, p. 2444-2449Article in journal (Refereed)
    Abstract [en]

    Custom orthopedic and dental implants may be fabricated by additive manufacturing (AM), for example using electron beam melting technology. This study is focused on the modification of the surface of Ti6Al4V alloy coin-like scaffolds fabricated via AM technology (EBM®) by radio frequency (RF) magnetron sputter deposition of hydroxyapatite (HA) coating. The scaffolds with HA coating were characterized by Scanning Electron microscopy, X-ray diffraction. HA coating showed a nanocrystalline structure with the crystallites of an average size of 32±9 nm. The ability of the surface to support adhesion and the proliferation of human mesenchymal stem cells was studied using biological short-term tests in vitro. In according to in vitro assessment, thin HA coating stimulated the attachment and proliferation of cells. Human mesenchymal stem cells cultured on the HA-coated scaffold also formed mineralized nodules.

  • 9.
    Douglas, T
    et al.
    LANCASTER UNIVERSITY, UK.
    Hempel, U
    INSTITUTE OF PHYSIOLOGICAL CHEMISTRY, TECHNISCHE UNIVERSITÄT DRESDEN, GERMANY.
    Żydek, J
    AGH UNIVERSITY OF SCIENCE AND TECHNOLOGY, KRAKOW, POLAND.
    Buchweitz, M
    TOMSK POLYTECHNIC UNIVERSITY, RUSSIA.
    Surmenev, Roman
    Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, Maria
    Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics. SportsTech Research Centre, Mid Sweden University.
    Pamula, E
    AGH UNIVERSITY OF SCIENCE AND TECHNOLOGY, KRAKOW, POLAND.
    Pectin Coatings on Titanium Alloy Samples Produced by Additive Manufacturing: Promotion of Human Bone Marrow Stromal Cell Proliferation2017In: Engineering of Biomaterials, ISSN 1429-7248, Vol. 143, p. 43-Article in journal (Refereed)
  • 10.
    Douglas, Timothy E. L.
    et al.
    Lancaster University, United Kingdom.
    Hempel, Ute
    Technische Universität Dresden, Germany.
    Żydek, Jagoda
    AGH University of Science and Technology, Kraków, Poland.
    Vladescu, Alina
    National Institute for Optoelectronics, Romania; National Research Tomsk Polytechnic University, Russia.
    Pietryga, Krzysztof
    AGH University of Science and Technology, Kraków, Poland.
    Kaeswurm, Julia A. H.
    University of Stuttgart, Germany.
    Buchweitz, Maria
    University of Stuttgart, Germany.
    Surmenev, Roman A.
    National Research Tomsk Polytechnic University, Russia.
    Surmeneva, Maria A.
    National Research Tomsk Polytechnic University, Russia.
    Cotrut, Cosmin M.
    National Research Tomsk Polytechnic University, Russia; University Politechnica of Bucharest, Romania.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Pamuła, Elzbieta
    AGH University of Science and Technology, Kraków, Poland.
    Pectin coatings on titanium alloy scaffolds produced by additive manufacturing: Promotion of human bone marrow stromal cell proliferation2018In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 227, p. 225-228Article in journal (Refereed)
    Abstract [en]

    Ti6Al4V is a popular biomaterial for load-bearing implants for bone contact, which can be fabricated by additive manufacturing technologies. Their long-term success depends on their stable anchoring in surrounding bone, which in turn depends on formation of new bone tissue on the implant surface, for which adhesion and proliferation of bone-forming cells is a pre-requisite. Hence, surface coatings which promote cell adhesion and proliferation are desirable. Here, Ti6Al4V discs prepared by additive manufacturing (EBM) were coated with layers of pectins, calcium-binding polysaccharides derived from citrus (C) and apple (A), which also contained alkaline phosphatase (ALP), the enzyme responsible for mineralization of bone tissue. Adhesion and proliferation of human bone marrow stromal cells (hBMSC) were assessed. Proliferation after 7 days was increased by A-ALP coatings and, in particular, by C-ALP coatings. Cell morphology was similar on coated and uncoated samples. In conclusion, ALP-loaded pectin coatings promote hBMSC adhesion and proliferation. 

  • 11.
    Fisher, Tatjana A.
    et al.
    Tyumen Research Centre, Siberian Branch of the Russian Academy of Sciences, Tyumen, Russia.
    Petrov, Sergey A.
    Tyumen Research Centre, Siberian Branch of the Russian Academy of Sciences, Tyumen, Russia.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sukhovey, Yurij G.
    Institute of Immunology, Tyumen, Russia.
    Dotsenko, Evgenij L.
    Tyumen State University, Tyumen, Russia.
    A way to health through psycho-immunological wellbeing: Example of Indigenous People of Russian North2016In: Proc. IIId Intl Conference "Psychological Health of the Person: Life Resource and Life Potential", 2016Conference paper (Refereed)
    Abstract [en]

    The research was carried out into the changes within psychic and immune domains ofthe Russian Nenets people migrating from the traditional northern habitat (tundra) to urbanenvironment. It is noted that in the process of significantly changing lifestyle supposedlysingle ethnic group can be clearly sub-divided according to the differences in adaptationdynamics. This division reflects sociological differences and is connected to the psychoimmunologicalaspects. Thus, with the adaptation of forest Nenets to the new conditions ofexistence (from the tundra to the urban centers), we found a division of a whole ethnic groupinto two groups according to a social attribute, which is fixed at the psychophysiologicallevel. First, psychic and immune domains are not only sharing a number of commonfeatures but also can have deep evolutionary connections and can be governed by similarlaws. Second, the psyche and the immune system show the most important functions andproperties that ensure an effective existence, generalizing the values of adaptation, protectionand vitality into a single structure. Such a concept is closed to “wholeness” and “integrity” showing that the distribution of vital forces or body resources can adjust the condition orcope with the pre-illness or even disease.

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  • 12.
    Katz-Demyanetz, Alexander
    et al.
    Technion R&D Fdn, Haifa, Israel.
    Popov, Vladimir V., Jr.
    Technion R&D Fdn, Haifa, Israel.
    Kovalevsky, Aleksey
    Technion R&D Fdn, Haifa, Israel.
    Safranchik, Daniel
    Technion R&D Fdn, Haifa, Israel.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Powder-bed additive manufacturing for aerospace application: Techniques, metallic and metal/ceramic composite materials and trends2019In: MANUFACTURING REVIEW, ISSN 2265-4224, Vol. 6, article id 5Article, review/survey (Refereed)
    Abstract [en]

    The current paper is devoted to classification of powder-bed additive manufacturing (PB-AM) techniques and description of specific features, advantages and limitation of different PB-AM techniques in aerospace applications. The common principle of "powder-bed" means that the used feedstock material is a powder, which forms "bed-like" platform of homogeneous layer that is fused according to cross-section of the manufactured object. After that, a new powder layer is distributed with the same thickness and the "printing" process continues. This approach is used in selective laser sintering/melting process, electron beam melting, and binder jetting printing. Additionally, relevant issues related to powder raw materials (metals, ceramics, multi-material composites, etc.) and their impact on the properties of as-manufactured components are discussed. Special attention is paid to discussion on additive manufacturing (AM) of aerospace critical parts made of Titanium alloys, Nickel-based superalloys, metal matrix composites (MMCs), ceramic matrix composites (CMCs) and high entropy alloys. Additional discussion is related to the quality control of the PB-AM materials, and to the prospects of new approaches in material development for PB-AM aiming at aerospace applications.

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  • 13.
    Khrapov, D.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Manabaev, K.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Léonard, F.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Mishurova, T.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Bruno, G.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany; University of Potsdam,, Potsdam, Germany.
    Cheneler, D.
    Lancaster University, Bailrigg, Lancaster, United Kingdom.
    Loza, K.
    University of Duisburg-Essen, Essen, Germany.
    Epple, M.
    University of Duisburg-Essen, Essen, Germany.
    Surmenev, R.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, M.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    The impact of post manufacturing treatment of functionally graded Ti6Al4V scaffolds on their surface morphology and mechanical strength2020In: Journal of Materials Research and Technology, ISSN 2238-7854, Vol. 9, no 2, p. 1866-1881Article in journal (Refereed)
    Abstract [en]

    An ultrasonic vibration post-treatment procedure was suggested for additively manufactured lattices. The aim of the present research was to investigate mechanical properties and the differences in mechanical behavior and fracture modes of Ti6Al4V scaffolds treated with traditional powder recovery system (PRS) and ultrasound vibration (USV). Scanning electron microscopy (SEM) was used to investigate the strut surface and the fracture surface morphology. X-ray computed tomography (CT) was employed to evaluate the inner structure, strut dimensions, pore size, as well as the surface morphology of additively manufactured porous scaffolds. Uniaxial compression tests were conducted to obtain elastic modulus, compressive ultimate strength and yield stress. Finite element analysis was performed for a body-centered cubic (BCC) element-based model and for CT-based reconstruction data, as well as for a two-zone scaffold model to evaluate stress distribution during elastic deformation. The scaffold with PRS post treatment displayed ductile behavior, while USV treated scaffold displayed fragile behavior. Double barrel formation of PRS treated scaffold was observed during deformation. Finite element analysis for the CT-based reconstruction revealed the strong impact of surface morphology on the stress distribution in comparison with BCC cell model because of partially molten metal particles on the surface of struts, which usually remain unstressed. 

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  • 14.
    Khrapov, D.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, M.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Evsevleev, S.
    Federal Institute for Materials Research and Testing (BAM), Berlin, Germany.
    Lé Onard, F.
    Federal Institute for Materials Research and Testing (BAM), Berlin, Germany.
    Bruno, G.
    Federal Institute for Materials Research and Testing (BAM), Berlin, Germany.
    Surmenev, R.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    X-ray computed tomography of multiple-layered scaffolds with controlled gradient cell lattice structures fabricated via additive manufacturing2019Conference paper (Refereed)
    Abstract [en]

    In this paper we report on the characterization by X-ray computed tomography of calcium phosphate (CaP) and polycaprolactone (PCL) coatings on Ti-6Al-4V alloy scaffolds used as a material for medical implants. The cylindrical scaffold has greater porosity of the inner part than the external part, thus, mimicking trabecular and cortical bone, respectively. The prismatic scaffolds have uniform porosity. Surface of the scaffolds was modified with calcium phosphate (CaP) and polycaprolactone (PCL) by dip-coating to improve biocompatibility and mechanical properties. Computed tomography performed with X-ray and synchrotron radiation revealed the defects of structure and morphology of CaP and PCL coatings showing small platelet-like and spider-web-like structures, respectively. 

  • 15.
    Khrapov, D.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, M.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Surmenev, R.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Microstructure investigation of Ti-26Nb alloy manufactured from elemental powders by electron beam melting2019In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, no 1, article id 012126Article in journal (Refereed)
    Abstract [en]

    Alloys which are planned to be used for implants fabrication must possess excellent biocompatibility, high strength, and low Young's modulus. A low elastic modulus, close to that of the cortical bone could significantly reduce the stress-shielding phenomenon usually occurring after surgery. Beta-titanium alloys such as Ti-Nb are good candidates for this purpose. Nb is known as a biocompatible metal used for titanium β-phase stabilization. Previous investigations indicate that the increase of Nb content results in the increase of β phase amount but the decrease of β grain size. In this study, we were aiming at the investigation of the microstructural properties of a titanium alloy manufactured by electron beam melting from the elemental powders mixture of Ti and Nb with 26 at.% of Nb. The influence of operating parameters on the efficacy of dissolving Nb particles in Ti was studied. The results obtained by SEM analysis demonstrated that electron beam energy has a significant effect on the homogeneity of the manufactured specimens. To obtain homogeneous and porosity-free specimens high energy level is required. The microstructure of these specimens was characterized. © Published under licence by IOP Publishing Ltd.

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  • 16.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Nilsson, Kajsa
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Studying Moisture Transport Trough "Active" Fabrics Using Humidity-Temperature Sensor Nodes2018In: Proceedings, Volume 2, ISEA 2018: / [ed] Dr Hugo Espinosa, David R. Rowlands, Jonathan Shepherd, Professor David Thiel, 2018, Vol. 2, p. 230-, article id 6Conference paper (Refereed)
    Abstract [en]

    Active fabrics providing better comfort of the garments and footwear rapidly become an essential part of our life. However, only limited information about the performance of such fabrics is commonly available for the garment and footwear designers, and tests are often done only with the final products. Thus development of the objective testing methods for the fabric assemblies containing microporous membranes and garments using them is one of the important topics. Garment tests in the climate chamber when exercising in windy and rainy conditions with a set of temperature and humidity sensors placed over the body allow comparing manufactured garments for thermal and humidity comfort. To allow for better material testing a new laboratory setup was developed for studying the dynamics of the humidity transport through different fabrics at realistic conditions in extension of the existing ISO test procedure. Present paper discusses the experimental procedures and first results acquired with new setup.

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  • 17.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Botero Vega, Carlos Alberto
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Popov, Vladimir
    Israel Institute of Metals, Technion R&D Foundation, Technion City, 3200003, Haifa, Israel.
    Chudinova, Ekaterina
    Tomsk Polytechnic University, Tomsk, Russia.
    Developing new materials for Electron Beam Melting: experiences and challenges2018Conference paper (Refereed)
    Abstract [en]

    Lack of industrially available materials for additive manufacturing (AM) of metallic materials along with the promises of materials with improved or unique properties provides a strong drive for developing new process/material combinations. As powder bed technologies for metallic materials are relatively new to the market, and to some extent are only maturing, developers of new process/material combinations have certain challenges to overcome. Firstly, basic knowledge on the behavior of materials (even those well established for other applications) under extreme conditions of melting/solidification with beam-based AM methods is far from being adequate. Secondly, manufacturing of the equipment is up to date driven by industrial application, thus optimization of the AM machines for small test batches of powders is still belongs to research and development projects. Also, majority of the powder manufacturers are primarily driven by the market development, and even they are well aware of the demands imposed by the powder bed AM machines, availability of small test batches of adequate powders may be problematic or at least quite costly for the R&D oriented users. Present paper describes the experiences in developing new materials for EBM A2 machine by Arcam EBM, modified for operating with powder batches of 100-200 ml and less. In particular it discusses achievements and challenges of working with powders from different materials with specifications far beyond the range suggested by machine manufacturer. Also it discusses the possibility of using blended rather than pre-alloyed powders for achieving both composite-like and alloyed materials in the same part by steering electron beam energy deposition strategy.

  • 18.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    3D-printing: a future “magic wand” for global manufacturing. How can we benefit from it today for sports and health care?2017In: Proceedings of the 5th International Congress on Sport Sciences Research and Technology Support, icSPORTS / [ed] Jan Cabri, Pedro Pezarat Correia, INSTICC Press, 2017Conference paper (Refereed)
    Abstract [en]

    3D-printing, or as it is also known, additive manufacturing (AM), is promising to be one of the determining manufacturing technologies of the present century. It is not a single technology but a family of rather different ones common in the way components are made, adding materials layer by layer. Additive manufacturing is already quite competitive to existing and well established technologies, but it also can provide unprecedented flexibility and complexity of shapes making components from the materials as different as cheese, chocolate and cream, live cells, concrete, polymers and metal. Many more materials we were not even thinking about few years ago are also becoming available in additive manufacturing, making it really believable that “only the sky is the limit”. During the time available for the keynote lecture, we will analyze the present position of AM in relation to other technologies, the features that make it so promising and its influence upon the part of our life we call sports and health, using the examples relevant to the Congress areas from computer systems to sports performance. Out of all enormities of materials available for different representatives of this manufacturing family we will concentrate at polymers and metals. AM technologies working with these two material families are already providing some unique solutions within the application areas relevant to the Congress' scope. We will also talk about some limitations inherent to the AM in polymers and metals to have the awareness that though the limit is somewhere “high in the sky”, it still exists.

  • 19.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Popov, Vladimir V., Jr.
    Israel Institute of Metals, Haifa, Israel.
    Botero Vega, Carlos Alberto
    Jiménez-Piqué, Emilio
    Universitat Politècnica de Catalunya, Barcelona, Spain.
    Katz-Demyanetz, Alexander
    Israel Institute of Metals, Haifa, Israel.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Compositionally-tailored steel-based materials manufactured by electron beam melting using blended pre-alloyed powders2020In: Materials Science & Engineering: A, ISSN 0921-5093, E-ISSN 1873-4936, Vol. 771, article id 138587Article in journal (Refereed)
    Abstract [en]

    The paper presents the prospects of additive manufacturing (AM) in metal, using the powder bed fusion (PBF) method Electron Beam Melting (EBM) in fabrication specific steel-based alloys for different applications. The proposed approach includes manufacturing of metals from blended pre-alloyed powders for achieving in situ alloying and the material microstructure tailoring by controlling electron beam energy deposition rate EBM tests were conducted with the blends of 316L stainless steel and Colferoloys 103 and 139, corrosion- and abrasion-resistant iron based materials commonly used for plasma spray coating. Thorough microstructure analysis of the manufactured sample was carried out using electron microscopy and measurements of microhardness and elastic modulus was carried out using nanoindentation. It is concluded that implementation of blended powder pathway in PBF AM allows to widen the scope of available materials through diminishing the dependence on the availability of pre-alloyed powders. Together with beam energy steering this pathway also allows for an effective sample microstructure control at different dimensional scales, resulting in components with unique properties. Therefore, the implementation of ‘blended powder pathway’ in PBF AM provides a possibility of manufacturing components with the composite-like and homogeneous zones allowing for the microstructure control and effectively adding a “4th dimension” to “3D printing". 

  • 20.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Botero Vega, Carlos Alberto
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Popov, Vladimir
    Israel Institute of Metals, Technion R&D Foundation, Technion City, 3200003, Haifa, Israel.
    Unique material compositions obtained by Electron beam melting of blended powders2018In: Euro PM2018 Proceedings, European Powder Metallurgy Association, EPMA , 2018Conference paper (Refereed)
    Abstract [en]

    Today powder bed fusion based (PBF) additive manufacturing (AM) methods in metallic materials mainly employ pre-alloyed precursor powders. It was even somehow assumed that in situ alloying of the blended powders will not be effective and such PBF processing will not yield any valuable materials. Recent studies carried out both for laser- and electron beam- based PBF have demonstrated possibilities of using precursors blended from both elemental and alloyed powders. We also demonstrate that composites and alloys indeed can be manufactured from a range of different pre-blended powders with Electron Beam Melting (EBM). It is also possible achieving both composites and alloys by design in different parts of the manufactured components by varying the beam energy deposition strategy. Using sequentially fed precursor powders together with a new powder delivery system also allows manufacturing of the functionally graded materials with gradual composition variation. Blended powder precursors and sequential powder feeding should provide opportunities of manufacturing components with changing composition and material properties in a single manufacturing process. It makes possible modern industrial manufacturing of materials similar to Damascus steels, and other composites and composite-like materials in combinations with alloyed and gradient sections by choice in different parts of components.  

  • 21.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Schieber, Erika
    Persson, Jonas
    Possibility of modern humidity sensor application in the studies ofmoisture transport through the sports and outdoor garments2016In: icSPORTS 2016 - Proceedings of the 4th International Congress on Sport Sciences Research and Technology Support, Portugal: SciTePress, 2016, p. 51-58Conference paper (Refereed)
    Abstract [en]

    Sensor nodes containing pairs of temperature and humidity sensors were assessed as a mean of garmentperformance and comfort studies. Modern sensors are small, low weight and produce minimal disturbancewhen placed under the garments and in the footwear. Four sensor nodes were used to provide dynamicinformation about heat and humidity transfer properties of garments during the tests in realistic conditions.Pilot studies were carried out for the few models of cross country skiing garments and waders. Main studieswere carried out in the wind tunnel at Mid Sweden University having pivoted treadmill, temperature controland rain capacity. Additional experiments with the waders were carried out in a large water tank. Studies ofthe temperature and humidity dynamics under the garments containing microporous membranes illustratethe importance of recognizing main features of such materials. In particular, such membranes can onlytransport moisture from the side where humidity is higher. It means that garments and footwear containingsuch membranes will potentially behave differently when ambient air humidity changes. In particular,modern garments with incorporated microporous membranes being superior at low ambient air humidity canbe dramatically less effective for moisture transfer from the body in the rain.

  • 22.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Botero, Carlos
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Sjöström, William
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Jimenez-Pique, E
    Şelte, A
    Asvik, Kenneth
    Uddeholm.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Steel-based functionally gradient materials obtained via Electron Beam Melting2019In: Proc. Alloys for Additive Manufacturing Symposium AAMS2019, 2019Conference paper (Refereed)
    Abstract [en]

    Recent developments in metal Additive Manufacturing (AM) technologies have introduced great capabilities unparalleled by conventional manufacturing, not only in achieving freeform geometries, but also in opening new possibilities to tailor the microstructure/properties of materials by controlling process parameters. Electron Beam Melting (EBM) is one of the most important members of the Powder Bed Fusion(PBF) family; it uses a focused electron beam to melt metal powder in a layer by layer approach. One of the main challenges that EBM faces nowadays is the lack of commercially available materials (most of them are Ti-based or Ni-based alloys). Therefore, there is a strong interest to further develop the process for new materials, including steel-based ones. In this investigation two steel-based powders; stainless steel 316L and a tool steel developed by Uddeholm, were used to manufacture functionally graded materials. A special hardware setup using a single powder dispenser was installed in the EBM system, where powders were placed separately to manufacture 10x10x10 mm cubes. SEM images of the specimens’ polished cross sections show a gradual microstructural transition from characteristic 316L one on the bottom of the specimens to the tool steel towards the top. Nanoindentation experiments confirmed a consequent gradient in hardness and elastic modulus, which gradually increase towards top surface. These results show great possibilities to tailor microstructure and mechanical properties by combining different powders in the EBM technology. Potential applications include the tooling industry, where hard and wear-resistant materials are demanded on the surface whether tougher and more ductile behavior is desirable on the core of the tool.

  • 23.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics. SportsTech Research Centre, Mid Sweden University.
    Burkett, Brendan
    School of Health and Sport Sciences, University of Sunshine Coast, Australia.
    Editorial for the special issue technology for disability sport2016In: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 19, no 3, p. 1p. 139-139Article in journal (Refereed)
    Abstract [en]

    Major sporting events, including the Olympic Games, areroutinely ‘‘brought to our homes’’ by modern mass media.The Paralympic Games follow the Olympic Games, and areanother major competition event. With each summer andwinter Paralympic games, such as the 2012 London and the2014 Sochi Paralympic games, the elite sporting achievementsmay be new to many of us. The athletic skill andpersistent determination drive Paralympic sports. A commonthread with the Paralympic athlete is the reliance onsome form of technology to compete on the world stage.Engineering and technology have become an essentialpart of modern-day sports. This partnership is necessary forcoach and athlete as they prepare for, and participate incompetitions. From the audience perspective, sports technologycan provide a new perspective and insight into thecompetition and its highlights. The quality of equipment,garments and footwear, and their interaction with athlete’sbody become an integrated part of the winning strategy inmodern sports.For the athlete with a disability, engineering and technologyhas always been an essential partnership. Withoutthe assistive devices, the disabled athlete is not able toprepare and participate in sport. Equipment design fordisabled athletes is often more complex and customizedthan for many other applications.The fundamental principles for the use of equipment inParalympic Sport are safety, fairness, universality andphysical prowess. While the safety criterion is relativelystraightforward, fulfilling other three can be challenging forthe designers and classifiers. It is often impossible to showif the performance of an athlete with a particular assistivedevice is determined by the athlete rather than by ‘‘theimpact of technology and equipment’’. By working togetherwith all parties the sports engineering community canprovide affordable safe and reliable assistive devices,technologies for training and rehabilitation, and animproved basis for objective classification.Research papers in this issue deal with a wide variety ofsubjects and are multidisciplinary. Four papers in thisspecial issue are related to the athlete and equipmentinteraction, which is important in all sports but needsspecial care and precision when working with of paraathletes.The remaining five papers are related to issuesimportant for the training and classification.We hope that these contributions will improve theintegration between athlete and equipment, will provide abetter basis for proper classification of the equipment andassistive devices, and, according to the International ParalympicCommittee vision, will ‘‘enable para-athletes toachieve sporting excellence and inspire and excite theworld’’.

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  • 24.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics. Mid Sweden University, Dept of Mechanical Engineering.
    Bäckstöm, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics. SportsTech Research Centre, Mid Sweden University.
    Petrone, Nicola
    Department of Industrial Engineering, University of Padova, Via Venezia 1, 35131 Padova, Italy.
    Developing an Instrumented Physical Model of the Human Head for Studying Concussion Mechanisms2017In: Proceedingd of iSSs-  (International Ski Safety Society): The Ski Trauma and Ski Safety Congress, 2017, Vol. AprilConference paper (Refereed)
  • 25.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    New Materials for Additive Manufacturing in Metal: Back to Basics?2017Conference paper (Refereed)
    Abstract [en]

    Advantages of Additive Manufacturing (AM) technologies benefit from the freedom of component shapes achievable in a single manufacturing process, short design-to-market times, and energy and material efficiency. AM in metal also allows for extremely high quality of the material, low residual stress in "as manufactured" parts (especially with Electron Beam Melting, EBM®), and gives promise of exciting new materials with unique composition and properties. Beam- based additive manufacturing in metal uses sources with extremely high energy density like lasers and electron beams resulting in fast melting-solidification dynamics. Materials produced at such conditions often have unique microstructure and properties, which allows speaking about new, non-stationary metallurgy. Knowledge of traditional metallurgical processes, which are mainly stationary, is often not adequate for understanding the processes involved with AM in metal, especially in cases of new materials. Along with some technological challenges this prevents fast growth of full-scale industrial application of AM. Though extensive research is carried out on new materials for AM, so far it is mainly centered at the development of process parameters for the materials already known from more traditional technologies. And at the moment it is an art rather than science as additive manufacturing in metal is far from being a “push-button” process. In order to develop future materials with required microstructure utilizing in full unique manufacturing conditions it is important to go “back to basics” and carefully study the processes involved. Present paper outlines some of the existing research and technology challenges relevant to the industrial applications of the beam-based AM in metal and possible pathways to solutions basing on multiple years of practical work.

     

  • 26.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Shen, Zhijian
    Stockholm University, Dept. of Materials and Environmental Chemistry.
    New Metallurgy of Additive Manufacturing in Metal: Experiences from the Material and Process Development with Electron Beam Melting Technology (EBM)2016In: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 879, p. 996-1001Article in journal (Refereed)
    Abstract [en]

    Additive manufacturing (AM) is becoming one of the most discussed modern technologies. Significant achievements of the AM in metals today are mainly connected to the unprecedented freedom of component shapes this technology allows. But full potential of these methods lies in the development of new materials designed to be used specifically with AM. Proper understanding of the AM process will open up new possibilities, where material and component properties can be specifically tailored by controlling the parameters throughout the whole manufacturing process. Present paper discusses the issues related to the beam melting technologies AM and electron beam welding (EBW). We are speaking of new direction in material science that can be termed “non-stationary metallurgy”, using the examples from material and process development for EBW, electron beam melting (EBM®) and other additive manufacturing methods.

  • 27.
    Laptev, Roman
    et al.
    Tomsk Polytechnic University.
    Pushilina, Natalia
    Tomsk Polytechnic University.
    Kashkarov, Egor
    Tomsk Polytechnic University.
    Syrtanov, Maxim
    Tomsk Polytechnic University.
    Stepanova, Ekaterina
    Tomsk Polytechnic University.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. Tomsk Polytechnic University.
    Lider, Andrey
    Tomsk Polytechnic University.
    Influence of beam current on microstructure of electron beam melted Ti-6Al-4V alloy2019In: Progress in Natural Science, ISSN 1002-0071, E-ISSN 1745-5391, Vol. 29, no 4, p. 440-446Article in journal (Refereed)
    Abstract [en]

    The defect microstructure of the samples manufactured from Ti-6Al-4V powder was studied using electron beam melting (EBM) in the beam current range of 17 - 13 mA. The hybrid digital complex combined positron lifetime spectroscopy and coincidence Doppler broadening spectroscopy was used to characterize the defect structure of the materials. The microstructure and defects were also analyzed by transmission electron microscopy. It has been established that the main type of the defects in the EBM manufactured samples is dislocations. According to the conducted measurements and calculations, the dislocation density in the EBM manufactured samples exceeds by two orders the similar value for the cast Ti-6Al-4Valloy. Formation of Ti-Ti-Al nanoscale clusters has been found in the EBM manufactured samples.

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  • 28.
    Norris, Karl
    et al.
    Univ Lancaster, Lancaster, England.
    Mishukova, Oksana I.
    Natl Res Tomsk Polytech Univ, Tomsk, Russia.
    Zykwinska, Agata
    IFREMER, Nantes, France.
    Colliec-Jouault, Sylvia
    IFREMER, Nantes, France.
    Sinquin, Corinne
    IFREMER, Nantes, France.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Cuenot, Stephane
    Univ Nantes, Nantes, France.
    Kerns, Jemma G.
    Univ Lancaster, Lancaster, England.
    Surmeneva, Maria A.
    Natl Res Tomsk Polytech Univ, Tomsk, Russia.
    Surmenev, Roman A.
    Natl Res Tomsk Polytech Univ, Tomsk, Russia.
    Douglas, Timothy E. L.
    Univ Lancaster, Lancaster, England; Univ Lancaster, Lancaster, England.
    Marine Polysaccharide-Collagen Coatings on Ti6Al4V Alloy Formed by Self-Assembly2019In: Micromachines, ISSN 2072-666X, E-ISSN 2072-666X, Vol. 10, no 1, article id 68Article in journal (Refereed)
    Abstract [en]

    Polysaccharides of marine origin are gaining interest as biomaterial components. Bacteria derived from deep-sea hydrothermal vents can produce sulfated exopolysaccharides (EPS), which can influence cell behavior. The use of such polysaccharides as components of organic, collagen fibril-based coatings on biomaterial surfaces remains unexplored. In this study, collagen fibril coatings enriched with HE800 and GY785 EPS derivatives were deposited on titanium alloy (Ti6Al4V) scaffolds produced by rapid prototyping and subjected to physicochemical and cell biological characterization. Coatings were formed by a self-assembly process whereby polysaccharides were added to acidic collagen molecule solution, followed by neutralization to induced self-assembly of collagen fibrils. Fibril formation resulted in collagen hydrogel formation. Hydrogels formed directly on Ti6Al4V surfaces, and fibrils adsorbed onto the surface. Scanning electron microscopy (SEM) analysis of collagen fibril coatings revealed association of polysaccharides with fibrils. Cell biological characterization revealed good cell adhesion and growth on bare Ti6Al4V surfaces, as well as coatings of collagen fibrils only and collagen fibrils enhanced with HE800 and GY785 EPS derivatives. Hence, the use of both EPS derivatives as coating components is feasible. Further work should focus on cell differentiation.

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  • 29.
    Olsén, Jon
    et al.
    Stockholm University.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Saedi, Kamran
    Luleå university of Technology.
    Shen, Zhijian James
    Stockholm university.
    The Heterogenic Structure Formed During Electron Beam Melting of 316L Stainless Steel2018Conference paper (Refereed)
  • 30.
    Olsén, Jon
    et al.
    Stockholm University.
    Shen, Zhijian
    Stockholm University.
    Liu, Leifeng
    University of Birmingham, Birmingham, United Kingdom.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Micro- and macro-structural heterogeneities in 316L stainless steel prepared by electron-beam melting2018In: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 141, p. 1-7Article in journal (Refereed)
    Abstract [en]

    This is a study of the micro- and macrostructural variations in samples of stainless steel with the overall composition of the grade 316L, produced using electron beam melting. Electron beam melting is one of the processing methods under consideration for manufacturing some of the International Thermo- Nuclear Experimental Reactor In-Vessel components. Therefore further studies of the homogeneity of the material were conducted. Electron beam melting results in a complicated thermal history of the manufactured part giving a significant impact on the microstructure. A cellular structure that is often observed in samples prepared by selective laser melting was found in the top layers of the specimens. Further down, the structure changed until the cellular structure was almost non-existing, and the grain boundaries had become more pronounced. This revelation of a heterogeneous structure throughout the entire part is crucial for large-scale industrial applications like the Thermo- Nuclear Experimental Reactor to make sure that it is understood that the properties of the material might not be the same at every point, as well as to assure that the correct post-treatment is done. It is also exposed that a significant part of this change is due to molybdenum redistribution inside the sample when it diffuses from the cell boundaries into the cells, and into bigger agglomerates in the grain boundaries. This diffusion seems not to affect the microhardness of the samples. 

  • 31.
    Petrone, Nicola
    et al.
    University of Padova, Italy.
    Candiotto, Gianluca
    University of Padova, Italy.
    Marzella, Edoardo
    University of Padova, Italy.
    Uriati, Federico
    University of Padova, Italy.
    Carraro, Giovanni
    University of Padova, Italy.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Feasibility of using a novel instrumented human head surrogate to measure helmet, head and brain kinematics and intracranial pressure during multidirectional impact tests2019In: Journal of Science and Medicine in Sport, ISSN 1440-2440, E-ISSN 1878-1861, Vol. 22, no S1, p. S78-S84Article in journal (Refereed)
    Abstract [en]

    Objectives: Aim of the work is to present the feasibility of using an Instrumented Human Head Surrogate (IHHS-1) during multidirectional impacts while wearing a modern ski helmet. The IHHS-1 is intended to provide reliable and repeatable data for the experimental validation of FE models and for the experimental evaluation of modern helmets designed to enhance the degree of protection against multidirectional impacts. Design: The new IHHS-1 includes 9 triaxial MEMS accelerometers embedded in a silicone rubber brain, independently molded and presenting lobes separation and cerebellum, placed into an ABS skull filled with surrogate cerebrospinal fluid. A triaxial MEMS gyroscope is placed at the brain center of mass. Intracranial pressure can be detected by eight pressure sensors applied to the skull internal surface along a transversal plane located at the brain center of mass and two at the apex. Additional MEMS sensors positioned over the skull and the helmet allow comparison between outer and inner structure kinematics and surrogate CSF pressure behavior. Methods: The IHHS-1 was mounted through a Hybrid III neck on a force platform and impacted with a striker connected to a pendulum tower, with the impact energies reaching 24J. Impact locations were aligned with the brain center of mass and located in the back (sagittal axis), right (90° from sagittal axis), back/right (45°), and front right (135°) locations. Following dynamic data were collected: values of the linear accelerations and angular velocities of the brain, skull and helmet; intracranial pressures inside the skull. Results: Despite the relatively low intensity of impacts (HIC at skull max value 46), the skull rotational actions reached BrIC values of 0.33 and angular accelerations of 5216 rad/s2, whereas brain angular acceleration resulted between 1,44 and 2,1 times lower with similar values of BrIC. Conclusions: The IHHS-1 is a physical head surrogate that can produce repeatable data for the interpretation of inner structures behavior during multidirectional impacts with or without helmets of different characteristics. 

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  • 32.
    Petrone, Nicola
    et al.
    University of Padova, Italy.
    Carraro, Giovanni
    University of Padova, Italy.
    Dal Castello, Stefano
    University of Padova, Italy.
    Broggio, Luca
    University of Padova, Italy.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    A Novel Instrumented Human Head Surrogate For The Impact Evaluation Of Helmets2018In: Proceedings, Volume 2, ISEA 2018 / [ed] Dr Hugo Espinosa, David R. Rowlands, Jonathan Shepherd, Professor David Thiel, 2018, Vol. 2, p. 269-, article id 6Conference paper (Refereed)
    Abstract [en]

    A novel Human Head Surrogate was obtained from available MRI scans of a 50th percentile male human head. Addictive manufacturing was used to produce the skull, the brain and the skin. All original MRI geometries were partially smoothed and adjusted to provide the best biofidelity compatible with printing and molding technology. The skull was 3D-printed in ABS and ten pressure sensors were placed into it. The brain surrogate was cast from silicon rubber in the 3d-printed plastic molds. Nine tri-axial accelerometers (placed at the tops of the lobes, at the sides of the lobes, in the cerebellum and in the center of mass) and a three-axis gyroscope (at the center of mass) were inserted into the silicon brain during casting. The cranium, after assembly with brain, was filled with silicon oil mimicking the cerebral fluid. Silicon rubber was cast in additional 3d-printed molds to form the skin surrounding the cranium. The skull base was adapted to be compatible with the Hybrid-III neck and allow the exit of brain sensors cabling. Preliminary experiments were carried out proving the functionality of the surrogate. Results showed how multiple accelerometers and pressure sensors allowed a better comprehension of the head complex motion during impacts.

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  • 33.
    Petrone, Nicola
    et al.
    University of Padova, Italy.
    Giacomin, Marco
    University of Padova, Italy.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Racing Wheels’ Effect on Drag/Side Forces Acting on a Cyclist at Sportstech-Miun Wind Tunnel2018In: Proceedings, Volume 2, ISEA 2018 / [ed] Dr Hugo Espinosa, David R. Rowlands, Jonathan Shepherd, Professor David Thiel, 2018, Vol. 2, p. 210-, article id 6Conference paper (Refereed)
    Abstract [en]

    Abstract: the wind tunnel at the SportsTech Research Centre at Mid Sweden University (MIUN, Östersund) was opened in 2015 for sports technology research. It is dedicated primarily to analysis of equipment performance and garment development and especially suitable for roller skiing, running and cycling. The aim of this work was to develop a full-scale study to investigate the aerodynamic behaviour of a cyclist facing front and cross wind at different yaw angles (from 0° to 30°) and speeds. To reach this goal, a rotating structure supported by a force platform was constructed. It includes a set of rollers on which fully unrestrained cycling is possible. The method was applied to the comparison of three wheelsets (differing in material, height and shape of the rim, number and shape of spokes) in terms of drag and side aerodynamic forces during a cyclist’s ride at 30 km/h, while keeping all the other factors constant. Resulting curves allowed estimating differences of 4% and 9% when applied to a recent time trial competition.

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  • 34.
    Popov, Vladimir
    et al.
    Israel Institute of Metals, Technion RandD Foundation, Technion City, Haifa, Israel.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Radulov, Iliya
    Technische Universität Darmstadt, Darmstadt, Germany.
    Maccari, Fernando
    Technische Universität Darmstadt, Darmstadt, Germany.
    Muller, Gary
    Israel Institute of Metals, Technion RandD Foundation, Technion City, Haifa, Israel.
    Prospects of additive manufacturing of rare-earth and non-rare-earth permanent magnets2018In: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 21, p. 100-108Article in journal (Refereed)
    Abstract [en]

    Additive manufacturing (AM) or 3D-printing started as a prototyping technique in plastic has succeeded in metals for life safety applications as airspace and medical implants production. Today having advantages in fabricating products of desired shape, geometry, lightweight structures and required mechanical properties, 3D-printing faces a new challenge - AM of permanent magnets (PM). 3D-printing significantly simplifies manufacturing of net-shape bonded magnets, simplifies the new phase magnets prototyping, and also enables efficient use of rare earth (RE) elements [1]. The major development nowadays is performed by AM of bonded Nd-Fe-B using different binders/polymers [1, 2]. 3D printing technologies of non-RE magnets are not so widely represented [3]. The AM of RE-free PM, such as Al-Ni-Co [4] and MnAl(C) [5], is also developed, because of their great benefit of being non-RE, presenting advantages of AM technology and sufficient magnetic properties. This work presents the state-of-the-art of 3D-printing of PM, including RE and RE-free, bonded and non-bonded magnets. Prospects of electron beam melting (EBM) of non-rare-earth MnAl(C) are shown. 

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  • 35.
    Popov, Vladimir
    et al.
    Israel Institute of Metals, Technion R&D Foundation, Technion City, 3200003, Haifa, Israel.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. Mid Sweden University, Dept of Mechanical Engineering.
    Skokov, Konstantin
    Radulov, Iliya
    Gutfleisch, Oliver
    Selective electron beam melting of non-rare-earth MnAl-C permanent magnets2018In: Proceedings: 2d International Conference on Electron Beam Additive Manufacturing, EBAM 2018, 2018, Vol. April, p. 21-Conference paper (Refereed)
  • 36.
    Popov, Vladimir V., Jr.
    et al.
    Technion R&D Fdn, Haifa, Israel.
    Muller-Kamskii, Gary
    Technion R&D Fdn, Haifa, Israel.
    Katz-Demyanetz, Alexander
    Technion R&D Fdn, Haifa, Israel.
    Kovalevsky, Aleksey
    Technion R&D Fdn, Haifa, Israel.
    Usov, Stas
    Vet Clin Orthovet, St Petersburg, Russia.
    Trofimcow, Dmitrii
    Vet Clin Beliy Klyk, Moscow, Russia.
    Dzhenzhera, Georgy
    Polygon Med Engn, Moscow, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Additive manufacturing to veterinary practice: recovery of bony defects after the osteosarcoma resection in canines2019In: BIOMEDICAL ENGINEERING LETTERS, ISSN 2093-9868, Vol. 9, no 1, p. 97-108Article, review/survey (Refereed)
    Abstract [en]

    The paper outlines the achievements and challenges in the additive manufacturing (AM) application to veterinary practice. The state-of-the-art in AM application to the veterinary surgery is presented, with the focus of AM for patient-specific implants manufacturing. It also provides critical discussion on some of the potential issues design and technology should overcome for wider and more effective implementation of additively manufactured parts in veterinary practices. Most of the discussions in present paper are related to the metallic implants, manufactured in this case using so-called powder bed additive manufacturing (PB-AM) in titanium alloy Ti-6AL-4V, and to the corresponding process of their design, manufacturing and implementation in veterinary surgery. Procedures of the implant design and individualization for veterinary surgery are illustrated basing on the four performed surgery cases with dog patients. Results of the replacement surgery in dogs indicate that individualized additively manufactured metallic implants significantly increase chances for successful recovery process, and AM techniques present a viable alternative to amputation in a large number of veterinary cases. The same time overcoming challenges of implant individualization in veterinary practice significantly contributes to the knowledge directly relevant to the modern medical practice. An experience from veterinary cases where organ-preserving surgery with 3D-printed patient-specific implants is performed provides a unique opportunity for future development of better human implants.

  • 37.
    Popov, Vladimir V.
    et al.
    Israel Institute of Metals, Haifa, Israel.
    Katz-Demyanetz, Alexander
    Israel Institute of Metals, Haifa, Israel.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bamberger, Menachem
    Israel Institute of Technology, Haifa, Israel.
    Selective electron beam melting of Al0.5CrMoNbTa0.5 high entropy alloys using elemental powder blend2019In: Heliyon, ISSN 2405-8440, Vol. 5, no 2, article id e01188Article in journal (Refereed)
    Abstract [en]

    High Entropy Alloys (HEAs) is a novel promising class of multi-component materials which may demonstrate superior mechanical properties useful for high-temperature applications. Despite the high potential of HEAs, their production is complicated, using pre-alloyed powders in powder metallurgy route. This significantly complicates development and implementation of refractory BCC solid solution based HEAs. The present paper reports on experiments aiming at production of Al0.5CrMoNbTa0.5 multi-principle alloy using powder bed beam based additive manufacturing. Samples were manufactured using Selective Electron Beam Melting (SEBM) additive manufacturing technique from a blend of elemental powders aiming at achieving microstructure with high configurational entropy. Though it was not possible to achieve completely homogeneous microstructure, the as-printed material was composed of the zones with two multi-component solid solutions, which differed only by Al content confirming in situ alloying. The process parameters optimization was not carried out and the as-print material contained a notable amount of residual porosity. It was possible to reach lower porosity level using heat treatment at 1300 °C for 24 hours, however undesirable alloy composition changes took place. The main conclusion is that the production of the Al0.5CrMoNbTa0.5 multi-principle alloy from elemental powder blends using SEBM technique is achievable, but the process parameter optimization rather than post-process heat treatment should be performed to reduce the porosity of samples. 

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  • 38.
    Pushilina, Natalia
    et al.
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia.
    Panin, Alexey
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia; Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences, Tomsk, Russia.
    Syrtanov, Maxim
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia.
    Kashkarov, Egor
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia.
    Kudiiarov, Viktor
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia.
    Perevalova, Olga
    Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences, Tomsk, Russia.
    Laptev, Roman
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia.
    Lider, Andrey
    School of Nuclear Physics, National Research Tomsk Polytechnic University, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Hydrogen-induced phase transformation and microstructure evolution for Ti-6Al-4V parts produced by electron beam melting2018In: Metals, ISSN 2075-4701, Vol. 8, no 5, article id 301Article in journal (Refereed)
    Abstract [en]

    In this paper, phase transitions and microstructure evolution in titanium Ti-6Al-4V alloy parts produced by electron beam melting (EBM) under hydrogenation was investigated. Hydrogenation was carried out at the temperature of 650 °C to the absolute hydrogen concentrations in the samples of 0.29, 0.58, and 0.90 wt. %. Comparative analysis of microstructure changes in Ti-6Al-4V alloy parts was performed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Furthermore, in-situ XRD was used to investigate the phase transitions in the samples during hydrogenation. The structure of Ti-6Al-4V parts produced by EBM is represented by the α phase plates with the transverse length of 0.2 µm, the β phase both in the form of plates and globular grains, and metastable α'' and ω phases. Hydrogenation to the concentration of 0.29 wt. % leads to the formation of intermetallic Ti3Al phase. The dimensions of intermetallic Ti3Al plates and their volume fraction increase significantly with hydrogen concentration up to 0.58 wt. % along with precipitation of nano-sized crystals of titanium δ hydrides. Individual Ti3Al plates decay into nanocrystals with increasing hydrogen concentration up to 0.9 wt. % accompanied by the increase of proportion and size of hydride plates. Hardness of EBM Ti-6Al-4V alloy decreases with hydrogen content. 

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  • 39.
    Pushilina, Natalia
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Syrtanov, Maxim
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Kashkarov, Egor
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Murashkina, Tatyana
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Kudiiarov, Viktor
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Laptev, Roman
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Lider, Andrey
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Influence of Manufacturing Parameters on Microstructure and Hydrogen Sorption Behavior of Electron Beam Melted Titanium Ti-6Al-4V Alloy2018In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 11, no 5, article id 763Article in journal (Refereed)
    Abstract [en]

    Influence of manufacturing parameters (beam current from 13 to 17 mA, speed function 98 and 85) on microstructure and hydrogen sorption behavior of electron beam melted (EBM) Ti-6Al-4V parts was investigated. Optical and scanning electron microscopies as well as X-ray diffraction were used to investigate the microstructure and phase composition of EBM Ti-6Al-4V parts. The average alpha lath width decreases with the increase of the speed function at the fixed beam current (17 mA). Finer microstructure was formed at the beam current 17 mA and speed function 98. The hydrogenation of EBM Ti-6Al-4V parts was performed at the temperatures 500 and 650 degrees C at the constant pressure of 1 atm up to 0.3 wt %. The correlation between the microstructure and hydrogen sorption kinetics by EBM Ti-6Al-4V parts was demonstrated. Lower average hydrogen sorption rate at 500 degrees C was in the sample with coarser microstructure manufactured at the beam current 17 mA and speed function 85. The difference of hydrogen sorption kinetics between the manufactured samples at 650 degrees C was insignificant. The shape of the kinetics curves of hydrogen sorption indicates the phase transition alpha(H)+beta(H)->beta(H).

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  • 40.
    Radulov, I. A.
    et al.
    Technische Universit at Darmstadt, Darmstadt, Germany.
    Popov, V.V., Jr.
    Israel Institute of Metals, Technion R&D Foundation, Technion City, Haifa, Israel.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Maccari, F.
    Technische Universit at Darmstadt, Darmstadt, Germany.
    Kovalevsky, A.
    Israel Institute of Metals, Technion R&D Foundation, Technion City, Haifa, Israel.
    Essel, S.
    Israel Institute of Metals, Technion R&D Foundation, Technion City, Haifa, Israel.
    Gassmann, J.
    Fraunhofer Research Institution for Materials Recycling and Resource Strategies IWKS, Hanau, Germany.
    Skokov, K. P.
    Technische Universit at Darmstadt, Darmstadt, Germany.
    Bamberger, M.
    Technion Israel Institute of Technology, Technion City, Haifa, Israel.
    Production of net-shape Mn-Al permanent magnets by electron beam melting2019In: Additive Manufacturing, ISSN 2214-8604, Vol. 30, article id 100787Article in journal (Refereed)
    Abstract [en]

    The main goal of this work is the adoption of additive manufacturing for the production of inexpensive rare-earth free MnAl-based permanent magnets. The use of more advanced binder-free additive manufacturing technique such as Electron Beam Melting (EBM) allows obtaining fully-dense magnetic materials with advanced topology and complex shapes. We focus on the feasibility of controlling the phase formation in additively manufactured Mn-Al alloys by employing post-manufacturing heat treatment. The as-manufactured EBM samples contain 8% of the desired ferromagnetic τ-MnAl phase. After the optimized annealing treatment, the content of the τ-phase was increased to 90%. This sample has a coercivity value of 0.15 T, which is also the maximum achieved in conventionally produced binary MnAl magnets. Moreover, the EBM samples are fully dense and have the same density as the samples produced by conventional melting density. 

  • 41.
    Roos, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Botero Vega, Carlos Alberto
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Danvind, Jonas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Macro- and Micromechanical Behavior of 316LN Lattice Structures Manufactured by Electron Beam Melting2019In: Journal of materials engineering and performance (Print), ISSN 1059-9495, E-ISSN 1544-1024, Vol. 28, no 12, p. 7290-7301Article in journal (Refereed)
    Abstract [en]

    This work focuses on the possibility of processing stainless steel 316LN powder into lightweight structures using electron beam melting and investigates mechanical and microstructural properties in the material of processed components. Lattice structures conforming to ISO13314:2011 were manufactured using varying process parameters. Microstructure was examined using a scanning electron microscope. Compression testing was used to understand the effect of process parameters on the lattice mechanical properties, and nanoindentation was used to determine the material hardness. Lattices manufactured from 316L using EBM show smooth compression characteristics without collapsing layers and shear planes. The material has uniform hardness in strut shear planes, a microstructure resembling that of solid 316LN material but with significantly finer grain size, although slightly coarser sub-grain size. Grains appear to be growing along the lattice struts (e.g., along the heat transfer direction) and not in the build direction. Energy-dispersive x-ray spectroscopy analysis reveals boundary precipitates with increased levels of chromium, molybdenum and silicon. Studies clearly show that the 316LN grains in the material microstructure are elongated along the dominating heat transfer paths, which may or may not coincide with the build direction. Lattices made from a relatively ductile material, like 316LN, are much less susceptible to catastrophic collapse and show an extended range of elastic and plastic deformation. Tests indicate that EBM process for 316LN is stable allowing for both solid and lightweight (lattice) structures.

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  • 42.
    Roos, Stefan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Danvind, Jonas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Characterization of 316ln lattice structures fabricated via electron beam melting2017In: Materials Science and Technology Conference and Exhibition 2017, MS and T 2017, Association for Iron and Steel Technology, AISTECH , 2017, p. 336-343Conference paper (Refereed)
    Abstract [en]

    One of the promising application areas of additive manufacturing (AM) relates to light weight structures, including complex near net shape geometries and lattices. So far one of the limiting factors hampering wider industrial usage of AM technologies is the limited availability of processed materials. The aim of present study was to expand the previous success in electron beam melting (EBM®) manufacturing of 316LN bulk materials into thinner lattice structures thus further widening the application areas available for the method. Present paper reports on the initial results where lattice structures with octagonal basic cells were manufactured using EBM® and characterized using microscopy and compression testing. 

  • 43.
    Rännar, Lars-Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Olsén, Jon
    Stockholm University, Arrhenius Laboratory.
    Saeidi, Kamran
    Stockholm University, Arrhenius Laboratory.
    Shen, Zhijian
    Stockholm University, Arrhenius Laboratory.
    Hierarchical structures of stainless steel 316L manufactured by Electron Beam Melting2017In: Additive Manufacturing, ISSN 2214-8604, Vol. 17, p. 106-112Article in journal (Refereed)
    Abstract [en]

    One of the serious obstacles preventing wide industrial use of additive manufacturing (AM) in metals and alloys is a lack of materials available for this technology. It is particularly true for the Electron Beam Melting (EBM®) process, where only a few materials are commercially available, which significantly limits the use of the method. One of the dominant trends in AM today is developing processes for technological materials already widely used by other methods and developed for other industrial applications, gaining further advantages through the unique value added by additive manufacturing. Developing new materials specifically for additive manufacturing that can utilize the properties and specifics of the method in full is still a research and development subject, and such materials are yet far from full scale industrial usage. Stainless steels are widely used in industry due to good mechanical properties, corrosion resistance and low cost of material. Hence, there is potentially a market for this material and one possible business driver compared with casting for example is that lead times could be cut drastically by utilizing an additive approach for one-off or small series production. This paper presents results from the additive manufacturing of components from the known alloy 316L using EBM®. Previously the samples of 316L were made by laser-based AM technology. This work was performed as a part of the large project with the long term aim to use additively manufactured components in a nuclear fusion reactor. Components and test samples successfully made from 316L stainless steel using EBM® process show promising mechanical properties, density and hardness compared to its counterpart made by powder metallurgy (hot isostatic pressing, HIP). As with the other materials made by EBM® process, 316L samples show rather low porosity. Present paper also reports on the hierarchical microstructure features of the 316L material processed by EBM® characterized by optical and electron microscopy. 

  • 44.
    Skoglund, Per
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Botero Vega, Carlos Alberto
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Possibility of the “cold start” of the build in Electron Beam Melting2018Conference paper (Refereed)
  • 45.
    Sukhovey, Yurij G.
    et al.
    Institute of Clinical Immunology, Siberian Division of Russian Academy of Sciences, Tyumen, Russia.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics. SportsTech Research Centre, Mid Sweden University.
    Fisher, Tatjana A.
    Tyumen Research Centre, Siberian Division of Russian Academy of Sciences, Tyumen, Russia.
    Petrov, Sergey A.
    Tyumen State Oil and Gas Institute, Volodarskogo st. 38, , 625000, Tyumen, .
    Dotsenko, Evgenij L.
    Tyumen State University, Semakova st. 10, 625003, Tyumen, Russia.
    Functional Conjugation of the Different Regulatory Responses to the Stress Stimuli in Healthy Human Subjects2016In: Open Journal of Applied Sciences, ISSN 2165-3917, Vol. 6, p. 489-500Article in journal (Refereed)
    Abstract [en]

    Present article discusses the physiological mechanisms of the state employees adaptation duringactive training in temporary groups. It is suggested that adaptive mechanisms to adverse effectsmay be studied basing on the concept of functional isomorphism of the psychic and immune systems.Adaptive mechanisms were studied through the monitoring of the stress factors’ impact upon thelaw enforcement officers when training outside the places of permanent deployment. The specificpurpose of present study was to evaluate the physiological indicators of the psychic, immune andendocrine systems dynamics at different stages of adaptation of the live organism to a stressfulsituation, hoping to get better insight into possible relations between psychic and immune domains.Through monitoring of the dynamics of the endocrine and immune responses to the psychic stimuli,it was possible to correlate the stages of the stress onset to the phases of specific immune reactions.Strong correlations between the parameters characterizing activation of the psychic and immuneresponses support the hypothesis of the presence of “strong cooperation” between psychic andimmune domains. It supports earlier hypothesis that we are monitoring

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  • 46.
    Surmenev, Roman
    et al.
    Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, Maria
    Tomsk Polytechnic University, Tomsk, Russia.
    Chudinova, Ekaterina
    Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Melnikova, E.S.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Prymak, O.
    Epple, M.
    Wittmar, A.
    Ulbricht, M
    Surface modification of additive manufactured titanium with CaP, Ag nanoparticles and ultrathin HA coating2016In: Proceedings BIOMAH-2016, 2016Conference paper (Refereed)
  • 47.
    Surmeneva, Maria A.
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Khrapov, Dmitriy
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    Ivanov, Yuriy F.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation; Russian Academy of Sciences, Tomsk, Russian Federation.
    Mishurova, Tatiana
    Bundesanstalt für Materialforschung und –prüfung (BAM), Berlin, Germany.
    Evsevleev, Sergei
    Bundesanstalt für Materialforschung und –prüfung (BAM), Berlin, Germany.
    Prymak, Oleg
    University of Duisburg-Essen, Essen, Germany.
    Loza, Katerina
    University of Duisburg-Essen, Essen, Germany.
    Epple, Matthias
    University of Duisburg-Essen, Essen, Germany.
    Bruno, Giovanni
    Bundesanstalt für Materialforschung und –prüfung (BAM), Berlin, Germany; University of Potsdam, Potsdam, Germany.
    Surmenev, Roman A.
    National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
    In situ synthesis of a binary Ti–10at% Nb alloy by electron beam melting using a mixture of elemental niobium and titanium powders2020In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 282, article id 116646Article in journal (Refereed)
    Abstract [en]

    This study reports the results of the preliminary assessment to fabricate Ti-10at% Nb alloy by electron beam melting (EBM®) from a blend of elemental Nb and Ti powders. The microstructure of the EBM-manufactured Ti-10at% Nb alloys is sensitive to the following factors: different sintering properties of Nb and Ti powders, powder particle properties, material viscosities at varying melt pool temperatures, β-stabilizer element content and the EBM® process parameters. Three phases were observed in as-manufactured Ti-10at% Nb alloy: μm-size Nb phase, a Nb-rich β-solid solution surrounding Nb phase, lamellar structured α-phase and β-solid solution with different distribution and volume fraction. Thus, the combination of powder particle characteristics, very short time material spends in molten condition and sluggish kinetics of mixing and diffusional process in Ti-Nb alloy results in heterogeneous microstructures depending on the local Nb content in the powder blend and the EBM® process conditions. 

  • 48.
    Surmeneva, Maria A.
    et al.
    Natl Res Tomsk Polytech Univ, Russia.
    Surmenev, RomanA.
    Natl Res Tomsk Polytech Univ, Russia.
    Chudinova, Ekaterina A.
    Natl Res Tomsk Polytech Univ, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tkachev, Mikhail S.
    Natl Res Tomsk Polytech Univ, Russia.
    Gorodzha, Svetlana N.
    Natl Res Tomsk Polytech Univ, Russia.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Fabrication of multiple-layered gradient cellular metal scaffold via electron beam melting for segmental bone reconstruction2017In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 133, p. 195-204Article in journal (Refereed)
    Abstract [en]

    The triple-and double-layered mesh Ti-based alloy scaffolds were successfully fabricated using electron beam melting (EBM). In this study Ti-based alloy cylindrical scaffolds with different 3D architectures intended for the segmental bone defect treatment were systematically compared. All lattice-like scaffolds were additively manufactured using EBM technology from Ti6Al4V to mimic the structures of human trabecular bone. Cylindrically-shaped lattice scaffolds (outer diameter of 15 mm and length of 35 mm) of five different types were designed and manufactured. Four types were tubular with inner hole diameter of 5 mm and two lattice layers of different density. Fifth type was cylindrical with three lattice layers of different density. In all samples outer lattice layer was most dense, and inner layers-least dense. Mechanical properties of scaffolds were determined by conducting uniaxial compression testing. The strain-stress curves for all samples with gradient porosities showed considerable ductility.

  • 49.
    Surmeneva, Maria
    et al.
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Lapanje, Ales
    Jozef Stefan Institute, Ljubljana, Slovenia.
    Chudinova, Ekaterina
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Ivanova, Anna
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Loza, Kateryna
    University of Duisburg-Essen, Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany.
    Prymak, Oleg
    University of Duisburg-Essen, Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany.
    Epple, Matthias
    University of Duisburg-Essen, Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany.
    Ennen-Roth, Franka
    University of Duisburg-Essen, Technical Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany.
    Ulbricht, Mathias
    University of Duisburg-Essen, Technical Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), Essen, Germany.
    Rijavec, Tomaz
    Jozef Stefan Institute, Ljubljana, Slovenia.
    Surmenev, Roman
    National Research Tomsk Polytechnic University, Tomsk, Russia.
    Decreased bacterial colonization of additively manufactured Ti6Al4V metallic scaffolds with immobilized silver and calcium phosphate nanoparticles2019In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 480, p. 822-829Article in journal (Refereed)
    Abstract [en]

    The design of an ideal bone graft substitute has been a long-standing effort, and a number of strategies have been developed to improve bone regeneration. Electron beam melting (EBM) is an additive manufacturing method allowing for the production of porous implants with highly defined external dimensions and internal architectures. The increasing surface area of the implant may also increase the abilities of pathogenic microorganisms to adhere to the surfaces and form a biofilm, which may result in serious complications. The aim of this study was to explore the modifications of Ti6Al4V alloy scaffolds to reduce the abilities of bacteria to attach to the EBM-manufactured implant surface. The layers composed of silver (Ag), calcium phosphate (CaP) nanoparticles (NPs) and combinations of both were formed on the EBM-fabricated metallic scaffolds by electrophoretic deposition in order to provide them with antimicrobial properties. The assay of bacterial colonization on the surface was performed with the exposure of scaffold surfaces to Staphylococcus aureus cells for up to 17 h. Principal component analysis (PCA) was used to assess the relationships between different surface features of the studied samples and bacterial adhesion. The results indicate that by modifying the implant surface with appropriate nanostructures that change the hydrophobicity and the surface roughness at the nano scale, physical cues are provided that disrupt bacterial adhesion. Our results clearly show that AgNPs at a concentration of approximately 0.02 mg/сm 2 that were deposited together with CaPNPs covered by positively charge polyethylenimine (PEI) on the surface of EBM-sintered Ti6Al4V scaffolds hindered bacterial growth, as the total number of attached cells (NAC) of S. aureus remained at the same level during the 17 h of exposure, which indicates bacteriostatic activity. 

  • 50.
    Vladescu, Alina
    et al.
    National Institute for Optoelectronics, Romania; National Research Tomsk Polytechnic University, Lenin Avenue 43, Tomsk, Russian Federation.
    Vranceanu, Diana
    University Politehnica of Bucharest, Romania.
    Kulesza, Slawek
    Warmia and Mazury University in Olsztyn, Poland.
    Ivanov, Alexey
    Scientific Research Institute of Traumatology, Orthopedics and Neurosurgery, Russia.
    Bramowicz, Mirosław
    Warmia and Mazury University in Olsztyn, Poland.
    Fedonnikov, Alexander
    Scientific Research Institute of Traumatology, Orthopedics and Neurosurgery, Russia.
    Braic, Mariana
    National Institute for Optoelectronics, Romania.
    Norkin, Igor
    Scientific Research Institute of Traumatology, Orthopedics and Neurosurgery, Russia.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Kurtukova, Maria O.
    Saratov State Medical University, Russia.
    Dinu, Mihaela
    National Institute for Optoelectronics, Romania.
    Pana, Iulian
    National Institute for Optoelectronics, Romania.
    Surmeneva, Maria
    Tomsk Polytechnic University, Tomsk, Russia.
    Surmenev, Roman A.
    Tomsk Polytechnic University, Tomsk, Russia.
    Cotrut, Cosmin M.
    University Politehnica of Bucharest, Romania; Natl Res Tomsk Polytech Univ, Tomsk, Russia.
    Influence of the electrolyte’s pH on the properties of electrochemically deposited hydroxyapatite coating on additively manufactured Ti64 alloy2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, no 1, article id 16819Article in journal (Refereed)
    Abstract [en]

    Properties of the hydroxyapatite obtained by electrochemical assisted deposition (ED) are dependenton several factors including deposition temperature, electrolyte pH and concentrations, appliedpotential. All of these factors directly influence the morphology, stoichiometry, crystallinity,electrochemical behaviour, and particularly the coating thickness. Coating structure together withsurface micro- and nano-scale topography significantly influence early stages of the implant biointegration.The aim of this study is to analyse the effect of pH modification on the morphology,corrosion behaviour and in vitro bioactivity and in vivo biocompatibility of hydroxyapatite preparedby ED on the additively manufactured Ti64 samples. The coatings prepared in the electrolytes withpH = 6 have predominantly needle like morphology with the dimensions in the nanometric scale(~30 nm). Samples coated at pH = 6 demonstrated higher protection efficiency against the corrosiveattack as compared to the ones coated at pH = 5 (~93% against 89%). The in vitro bioactivity resultsindicated that both coatings have a greater capacity of biomineralization, compared to the uncoatedTi64. Somehow, the coating deposited at pH = 6 exhibited good corrosion behaviour and highbiomineralization ability. In vivo subcutaneous implantation of the coated samples into the white rats for up to 21 days with following histological studies showed no serious inflammatory process.

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