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  • 1.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. SportsTech Research Centre, Mid Sweden University.
    Michel, Frank
    Vaude Sports GmbH & Co., I-Team, Tettnang, Germany.
    Klauer, Robert
    Vaude Sports GmbH & Co., I-Team, Tettnang, Germany.
    Kopyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. Mid Sweden University, Dept of Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. SportsTech Research Centre, Mid Sweden University.
    Samuelsson, David
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Ahnesjö, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Litzenberger, Stefan
    Competence Center Sports Engineering, Biomechanics & Ergonomics, University of Applied Sciences Technikum, Wien, Austria.
    A Study of Skin-Close Heat and Moisture with Different Types of Backpacks in Cycling2020In: The 13th Conference of the International Sports Engineering Association / [ed] Motomu Nakashima, Takeo Maruyama and Yusuke Miyazaki, MDPI, 2020, Vol. 49, article id 86Conference paper (Refereed)
    Abstract [en]

    The aim of this project was to evaluate effects of backpacks with different design intended for use during cycling on skin-close temperature and relative humidity, oxygen uptake, heart rate and aerodynamic drag. Seven subjects took part in the study cycling on a mountain bike mounted on a “smart trainer” placed on a force plate in a wind tunnel. Three series of experiments were carried out: without backpack, with conventional backpack and with a backpack having innovative rear panel design. As hypothesized, the results showed that an innovatively designed backpack with the ducts deflecting part of the airflow towards some areas of the user’s back provided lower temperature and relative humidity for the microclimate compared to a conventional backpack without airflow channels. Further, reference tests without any backpack resulted in the lowest temperature and humidity. However, no differences were found between the three tests for oxygen uptake, heart rate and aerodynamic drag.

  • 2.
    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.

  • 3.
    Botero, Carlos Alberto
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Şelte, A.
    Ramsperger, M.
    Maistro, G.
    Koptyug, Andrey
    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.
    Sjöström, William
    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.
    Microstructural and mechanical evaluation of a cr-mo-v cold-work tool steel produced via electron beam melting (Ebm)2021In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 14, no 11, article id 2963Article in journal (Refereed)
    Abstract [en]

    In this work, a highly alloyed cold work tool steel, Uddeholm Vanadis 4 Extra, was manufactured via the electron beam melting (EBM) technique. The corresponding material microstructure and carbide precipitation behavior as well as the microstructural changes after heat treatment were characterized, and key mechanical properties were investigated. In the as-built condition, the mi-crostructure consists of a discontinuous network of very fine primary Mo-and V-rich carbides dispersed in an auto-tempered martensite matrix together with ≈15% of retained austenite. Adjusted heat treatment procedures allowed optimizing the microstructure by the elimination of Mo-rich carbides and the precipitation of fine and different sized V-rich carbides, along with a decrease in the retained austenite content below 2%. Hardness response, compressive strength, and abrasive wear properties of the EBM-manufactured material are similar or superior to its as-HIP forged counterparts manufactured using traditional powder metallurgy route. In the material as built by EBM, an impact toughness of 16–17 J was achieved. Hot isostatic pressing (HIP) was applied in order to further increase ductility and to investigate its impact upon the microstructure and properties of the material. After HIPing with optimized protocols, the ductility increased over 20 J. 

  • 4.
    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)
  • 5.
    Botero, Carlos
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Sjöström, William
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Jiménez-Piqué, Emilio
    Şelte, Aydın
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Functionally Graded Steels Obtained via Electron Beam Powder Bed Fusion2023In: Key Engineering Materials, ISSN 1013-9826, E-ISSN 1662-9795, Vol. 964, p. 79-84Article in journal (Refereed)
    Abstract [en]

    Electron-Beam Powder Bed Fusion (EB-PBF) is one of the most important metal additive manufacturing (AM) technologies. In EB-PBF, a focused electron beam is used to melt metal powders in a layer by layer approach. In this investigation two pre-alloyed steel-based powders, stainless steel 316L and V4E, a tool steel developed by Uddeholm, were used to manufacture functionally graded materials. In the proposed approach two powders are loaded into the feeding container, V4E powder on top of 316L one, preventing their mixing. Such type of feeding yields components with two distinct materials separated by a zone with gradual transition from 316L to V4E. Microstructure and local mechanical properties were evaluated in the manufactured samples. Optical Microscopy, Scanning Electron Microscopy and EDX on the polished cross-sections show a gradual microstructural and compositional transition from characteristic 316L at 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 the top surface of the samples. The achieved results provide great possibilities to tailor the composition, microstructure, mechanical properties, and wear resistance by combining different powders in the powder bed AM technology. Potential applications include the tooling industry, where hard and wear-resistant materials are demanded on the surface with tougher and more ductile materials in the core of the tool.

  • 6.
    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)
  • 7.
    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 Melting2020In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 19, no 5, 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.

  • 8.
    Bujtar, Peter
    et al.
    Southern General Hospital, Glasgow.
    Simonovics, Janos
    Southern General Hospital, Glasgow.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    George, Sandor
    Southern General Hospital, Glasgow.
    Varadi, Karoly
    Southern General Hospital, Glasgow.
    Emerging manufacturing bioengineering technologies 2: Scaffold designing experiment using titanium scaffolds2014In: British Journal of Oral & Maxillofacial Surgery, ISSN 0266-4356, E-ISSN 1532-1940, Vol. 52, no 8, p. e60-e61Article in journal (Refereed)
    Abstract [en]

    Substantial volume defects of the head and neck oftenrequire customized solutions to improve quality of life likefree flap transfers.Titanium and its alloys are versatile materialsproviding the feature of osteointegration. The conditionswhich facilitate the deposition of lamellar bone are underextensive research. Our project aimed to determine whethertitanium can function as a scaffold - unlike simple plates - toenhance bone regeneration for load bearing structures. Thereaction of stem cells to scaffolds with varying stiffness willbe presented.Additive manufacturing were used to produce a variety ofscaffolds to optimize titanium structures. Electric beam melting(EBM) manufacturing allowed us to optimize the elasticmodulus (Young) of the titanium to match with cadaveric 

    bone from a previous project. Multidirectional mechanicaltests were performed on the various designs of titanium cellstructures (n=80). The predictability and quality of manufacturingwas assessed statistically and also with scanningelectron microscope (SEM).The results demonstrated structures matching the mechanicalproperties of bone and even anisotropy as our resultssuggest 3GPa elasticity. This allows the possibility to buildregenerating bone with predictable properties. In addition,predictable patterning - unlike etching and sandblasting - ofmicroscopic (nano) features found to be significant and nonhomogenous simple repetitive patterns provide better cellularresponse.The benefit that tissue engineering techniques offer isdecreased morbidity, relative independence from donor site,with a highly specific and customized shape. Titanium basedreconstruction constructs seems to offer an alternative futurefor bony reconstruction.

  • 9.
    Bäckström, Mikael
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Carlsson, Peter
    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.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sundström, David
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    A New Wind Tunnel Facility Dedicated to Sports Technology Research and Development2016In: Procedia Engineering, Elsevier, 2016, Vol. 147, p. 62-67Conference paper (Refereed)
    Abstract [en]

    It is desirable to test sportswear and sports equipment at exactly the same conditions experienced during use. Although outdoor tests are in many cases the most adequate, they are at the same time quite complex, demand special measurement technology and wearable equipment. Results of such tests are often hard to interpret due to large variations because of rapidly varying ambient conditions and individual specifics of human objects, among other factors, which are hard or impossible to control. One common alternative is provided through indoor tests made in a stable, controlled environment. Controlling such parameters as temperature, wind speed and direction, air humidity with indoor facilities intended to replicate ambient conditions, and designed to house large objects, is a complex undertaking. Furthermore, replicating seasonal conditions complicates matters even more. A significant amount of research and development related to the operation of sports and other related equipment at high speeds and windy conditions has been carried out in wind tunnels with different degrees of climatic realism. However, the majority of such facilities are designed and constructed for the automotive industry, the aerospace industry and for marine research. A new wind tunnel facility, opened in March 2015 at the Sports Tech Research Centre at Mid Sweden University, is currently among the very few facilities in the world designed under the direct control of sports technology specialists and dedicated primarily to research and development within sports, outdoor clothing and footwear as well as equipment development and testing. The main goal when constructing this dedicated facility has been to successfully replicate ambient conditions for training and equipment testing in environments with controlled wind speed, temperature (+4 to +35°C) and precipitation (from fine mist to heavy downfall). The wind tunnel facility houses the largest moving belt in Sweden (5 m long and 2.7 m wide) which can be adjusted for leveled, uphill and downhill motion. The moving belt is placed in a 10 m2 test section in which the wind speed can be adjusted to match belt speed or independently up to 55 km/h (without narrowing the test section). A fog and rain system, mounted in the test section, can generate rainy conditions varying from fine mist to heavy monsoon. It is also possible to open the facility in order to allow experiments to be performed in wide range of outdoor, ambient conditions. This paper presents the basic parameters of the new wind tunnel facility. As this facility is open for wider international cooperation, we also report the general directions of current research and the future work planned to be carried out at this facility.

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  • 10.
    Bäckström, Mikael
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    People and Skis2006In: Science-First Hand, ISSN 1810-8520, no 3, p. 110-125Article in journal (Other (popular science, discussion, etc.))
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  • 11.
    Bäckström, Mikael
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Method and system for generating a driver support product for a racing driver2016Patent (Other (popular science, discussion, etc.))
  • 12.
    Bäckström, Mikael
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptyug, Andrey
    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.
    Carlsson, Peter
    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.
    Wiklund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sports Technology Education at Mid Sweden University2013In: 6TH ASIA-PACIFIC CONGRESS ON SPORTS TECHNOLOGY (APCST), Elsevier, 2013, Vol. 60, p. 214-219Conference paper (Refereed)
    Abstract [en]

    In present paper we would like to share some experiences of building new education in Sports Technology at MidSweden University and the results of 10 years of successfully running it in Östersund. The Sports Technologyeducation at Mid Sweden University started at Campus Östersund in 2003 as a part of the curriculum of theEngineering Department. This specialization was initially at the three-year Bachelor level, and later it was extendedto an additional two-year Master level. Aiming at the quality of Sports Technology education, three keystones areunderlying its process, representing the solid knowledge base, capacity to be flexible in problem solving and the usean innovative approaches. The Department unites researches with a background in both natural sciences andengineering disciplines, having a wide experience of working with and within the industry, equally active in researchand teaching. The unique constellation of the profiles forming the Department include not only the SportsTech®group, being “the backbone”, but also the Ecology and Eco-technology, and Quality Technology groups bringing theexcellence and extra competence needed to assure the quality of the Sports Technology education. We were the firsthigher education institution in Sweden to give this kind of education program and now some other SwedishUniversities have followed us. Our success can be measured by a number of graduates taking good jobs in theindustry. We also enjoy a steady flow of new students coming from all parts of Sweden, and Sports Technologyeducation stays among the most desirable ones in the country.

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  • 13. Carle, Fredrik
    et al.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Portable rescue device and a method for locating such a device2007Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    A portable rescue device and a method for locating, by means of a first rescue device set in a search mode, a second rescue device set in a distress mode. In the method, a distress signal carrying a device identification is received from said second rescue device. A first bearing and a second bearing to the second rescue device are obtained. The first and second bearings are taken from a first and a second position, respectively. A distance between these positions is determined. A current distance and a current bearing to the second rescue device are determined on basis of the first and second bearings and the distance. The current bearing and the current distance are communicated to a user of the first rescue device. The portable rescue device is used for performing the method and for that purpose it includes a first communication unit for distress signal transmission and reception; a compass; a processor; a user interface; and a mode switch for switching between a search mode and a distress signal mode. The first communication device has an antenna structure that provides directional capability.

  • 14.
    Carlsson, Peter
    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.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sundström, David
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Esping, Björn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptioug, Andrey
    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.
    Cross-Country Ski2015In: The Engineering Approach to Winter Sports / [ed] Braghin F., Cheli F., Maldifassi S., Melzi S. and Sabbioni E., Springer, 2015, p. 107-152Chapter in book (Other academic)
    Abstract [en]

    Cross-country skiing, biathlon and ski orienteering are competitive sports with practitioners who are mostly from countries in the northern hemisphere. The competition season is during the time when the ground is covered with snow, which roughly extends from mid-November to late March. During the rest time of the year, which is a long preparatory period of training for the skiers before the competition season, the skiers use roller skis for dryland training with the aim of imitating skiing on snow. Furthermore, over the last few decades, fairly specific indoor testing methods for cross-country skiers have become possible due to the development of treadmills that allow roller skiing using classical and freestyle techniques.

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  • 15. Chudinova, E.
    et al.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. SportsTech Research Centre.
    Mukhortova, Y.
    Pryadko, A.
    Volkova, A.
    Ivanov, A.
    Plotnikov, E.
    Khan, Y.
    Epple, M.
    Sokolova, V.
    Prymak, O.
    Douglas, T.
    Surmenev, R.
    Surmeneva, M.
    Functionalization of additive-manufactured Ti6Al4V scaffolds with poly(allylamine hydrochloride)/poly(styrene sulfonate) bilayer microcapsule system containing dexamethasone2021In: Materials Chemistry and Physics, ISSN 0254-0584, E-ISSN 1879-3312, Vol. 273, article id 125099Article in journal (Refereed)
    Abstract [en]

    Porous titanium alloy Ti6Al4V scaffolds manufactured via electron beam melting (EBM®) reveal broad prospects for applications in bone tissue engineering. However, local inflammation and even implant failure may occur while placing an implant into the body. Thus, the application of drug carriers to the surface of a metallic implant can provide treatment at the inflammation site. In this study, we propose to use polyelectrolyte (PE) microcapsules formed by layer-by-layer (LbL) synthesis loaded with both porous calcium carbonate (CaCO3) microparticles and the anti-inflammatory drug dexamethasone (DEX) to functionalize implant surfaces and achieve controlled drug release. Scanning electron microscopy indicated that the CaCO3 microparticles coated with PE bilayers loaded with DEX had a spherical shape with a diameter of 2.3 ± 0.2 μm and that the entire scaffold surface was evenly coated with the microcapsules. UV spectroscopy showed that LbL synthesis allows the manufacturing of microcapsules with 40% DEX. According to high performance liquid chromatography (HPLC) analysis, 80% of the drug was released within 24 h from the capsules consisting of three bilayers of polystyrene sulfonate (PSS) and poly(allylamine)hydrochloride (PAH). The prepared scaffolds functionalized with CaCO3 microparticles loaded with DEX and coated with PE bilayers showed hydrophilic surface properties with a water contact angle below 5°. Mouse embryonic fibroblast cells were seeded on Ti6Al4V scaffolds with and without LbL surface modification. The surface modification with LbL PE microcapsules with CaCO3 core affected cell morphology in vitro. The results confirmed that DEX had no toxic effect and did not prevent cell adhesion and spreading, thus no cytotoxic effect was observed, which will be further studied in vivo. 

  • 16.
    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. 

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  • 17.
    Chudinova, E.
    et al.
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Surmeneva, M.
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sharonova, A.
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Loza, K.
    Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Essen, Germany .
    Surmenev, R.
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Surface modification of additive manufactured Ti6Al4V alloy with Ag nanoparticles: Wettability and surface morphology study2016In: IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing (IOPP), 2016, Vol. 116, no 1, article id 012004Conference paper (Refereed)
    Abstract [en]

    In this work, the use of electrophoretic deposition to modify the surface of Ti6Al4V alloy fabricated via additive manufacturing technology is reported. Poly(vinylpyrrolidone) (PVP)-stabilized silver nanoparticles (AgNPs) had a spherical shape with a diameter of the metallic core of 100±20 nm and ζ -potential -15 mV. The AgNPs- coated Ti6Al4V alloy was studied in respect with its chemical composition and surface morphology, water contact angle, hysteresis, and surface free energy. The results of SEM microphotography analysis showed that the AgNPs were homogeneously distributed over the surface. Hysteresis and water contact angle measurements revealed the effect of the deposited AgNPs layer, namely an increased water contact angle and decreased contact angle hysteresis. However, the average water contact angle was 125° for PVP-stabilized-AgNPs-coated surface, whereas ethylene glycol gave the average contact angle of 17°. A higher surface energy is observed for AgNPs-coated Ti6Al4V surface (70.17 mN/m) compared with the uncoated surface (49.07 mN/m).

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  • 18.
    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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  • 19.
    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. 

  • 20.
    Chudinova, Ekaterina
    et al.
    Tomsk Polytechnic University, Tomsk, Russia.
    Surmeneva, Maria
    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.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Surmenev, Roman
    Tomsk Polytechnic University, Tomsk, Russia.
    Additive manufactured Ti6Al4V scaffolds with the RF-magnetron sputter deposited hydroxyapatite coating2016In: Journal of Physics: Conference Series, Institute of Physics Publishing (IOPP), 2016, Vol. 669, article id 012004Conference paper (Refereed)
    Abstract [en]

    Present paper reports on the results of surface modification of the additively manufactured porous Ti6Al4V scaffolds. Radio frequency (RF) magnetron sputtering was used to modify the surface of the alloy via deposition of the biocompatible hydroxyapatite (HA) coating. The surface morphology, chemical and phase composition of the HA-coated alloy were studied. It was revealed that RF magnetron sputtering allows preparing a homogeneous HA coating onto the entire surface of scaffolds.

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  • 21.
    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.

  • 22.
    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.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sharanova, A
    Tomsk Polytechnic University, Tomsk, Russia.
    Loza, K
    University of Duisburg-Essen, Germany.
    Epple, M
    University of Duisburg-Essen, Germany.
    Surmenev, Roman
    Tomsk Polytechnic University, Tomsk, Russia.
    Hydroxyapatite coating and silver nanoparticles assemblies on additively manufactured Ti6Al4V scaffolds2015Conference paper (Other academic)
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  • 23.
    Cronskär, Marie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Application of electron beam melting to titanium hip stem Implants2008In: / [ed] Katalinic, B., Vienna: DAAAM International Vienna , 2008, p. 1559-1560Conference paper (Refereed)
    Abstract [en]

    The Free Form Fabrication Process (FFF) is nowadays an accepted technology widely used for prototyping and manufacturing. However, it is still in an expansive phase and new applications like direct manufacturing of implants are evolving continuously. Present work describes the possibilities provided by the electron beam melting (EBM) method for orthopedics; in particular hip stem implant manufacturing. The conventional machining used for individually adapted prostheses typically involves advanced milling with the drawback of removing up to 80% of the material. This paper addresses the economic feasibility of using an additive approach for the manufacturing of typical orthopedic implants. The studied implants were manufactured from biocompatible Ti-6Al-4V alloy using both EBM and conventional CNC technologies and compared according to material consumption, manufacturing time and cost.

  • 24.
    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)
  • 25.
    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. 

  • 26.
    Evsevleev, Sergei
    et al.
    Bundesanstalt Mat Forsch & Prufung BAM, Unter Eichen 87, D-12205 Berlin, Germany..
    Mishurova, Tatiana
    Bundesanstalt Mat Forsch & Prufung BAM, Unter Eichen 87, D-12205 Berlin, Germany..
    Khrapov, Dmitriy
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, 30 Lenina Ave, Tomsk 634050, Russia..
    Paveleva, Aleksandra
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, 30 Lenina Ave, Tomsk 634050, Russia..
    Meinel, Dietmar
    Bundesanstalt Mat Forsch & Prufung BAM, Unter Eichen 87, D-12205 Berlin, Germany..
    Surmenev, Roman
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, 30 Lenina Ave, Tomsk 634050, Russia..
    Surmeneva, Maria
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, 30 Lenina Ave, Tomsk 634050, Russia..
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering. Tomsk Polytech Univ, Russia.
    Bruno, Giovanni
    Bundesanstalt Mat Forsch & Prufung BAM, Unter Eichen 87, D-12205 Berlin, Germany.;Univ Potsdam, Inst Phys & Astron, Karl Liebknecht Str 24-24, D-14476 Potsdam, Germany..
    X-ray Computed Tomography Procedures to Quantitatively Characterize the Morphological Features of Triply Periodic Minimal Surface Structures2021In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 14, no 11, article id 3002Article in journal (Refereed)
    Abstract [en]

    Additively manufactured (AM) metallic sheet-based Triply Periodic Minimal Surface Structures (TPMSS) meet several requirements in both bio-medical and engineering fields: Tunable mechanical properties, low sensitivity to manufacturing defects, mechanical stability, and high energy absorption. However, they also present some challenges related to quality control, which can prevent their successful application. In fact, the optimization of the AM process is impossible without considering structural characteristics as manufacturing accuracy, internal defects, as well as surface topography and roughness. In this study, the quantitative non-destructive analysis of TPMSS manufactured from Ti-6Al-4V alloy by electron beam melting was performed by means of X-ray computed tomography (XCT). Several advanced image analysis workflows are presented to evaluate the effect of build orientation on wall thicknesses distribution, wall degradation, and surface roughness reduction due to the chemical etching of TPMSS. It is shown that the manufacturing accuracy differs for the structural elements printed parallel and orthogonal to the manufactured layers. Different strategies for chemical etching show different powder removal capabilities and both lead to the loss of material and hence the gradient of the wall thickness. This affects the mechanical performance under compression by reduction of the yield stress. The positive effect of the chemical etching is the reduction of the surface roughness, which can potentially improve the fatigue properties of the components. Finally, XCT was used to correlate the amount of retained powder with the pore size of the functionally graded TPMSS, which can further improve the manufacturing process.

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  • 27. Facchetti, D.
    et al.
    Hempel, U.
    Martocq, L.
    Smith, A. M.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Surmenev, R. A.
    Surmeneva, M. A.
    Douglas, T. E. L.
    Heparin enriched-wpi coating on ti6al4v increases hydrophilicity and improves proliferation and differentiation of human bone marrow stromal cells2022In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 23, no 1, article id 139Article in journal (Refereed)
    Abstract [en]

    Titanium alloy (Ti6Al4V) is one of the most prominent biomaterials for bone contact because of its ability to bear mechanical loading and resist corrosion. The success of Ti6Al4V implants depends on bone formation on the implant surface. Hence, implant coatings which promote adhesion, proliferation and differentiation of bone-forming cells are desirable. One coating strategy is by adsorption of biomacromolecules. In this study, Ti6Al4V substrates produced by additive manufacturing (AM) were coated with whey protein isolate (WPI) fibrils, obtained at pH 2, and heparin or tinzaparin (a low molecular weight heparin LMWH) in order to improve the proliferation and differentiation of bone-forming cells. WPI fibrils proved to be an excellent support for the growth of human bone marrow stromal cells (hBMSC). Indeed, WPI fibrils were resistant to sterilization and were stable during storage. This WPI-heparin-enriched coating, especially the LMWH, enhanced the differentiation of hBMSC by increasing tissue non-specific alkaline phosphatase (TNAP) activity. Finally, the coating increased the hydrophilicity of the material. The results confirmed that WPI fibrils are an excellent biomaterial which can be used for biomedical coatings, as they are easily modifiable and resistant to heat treatments. Indeed, the already known positive effect on osteogenic integration of WPI-only coated substrates has been further enhanced by a simple adsorption procedure. 

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  • 28.
    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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  • 29.
    Frisk, Karin
    et al.
    Swerea KIMAB, Kista.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Petterson, Niklas
    Swerea KIMAB, Kista.
    Persson, Daniel
    Swerea KIMAB, Kista.
    Leicht, Alexander
    Chalmers.
    Vattur Sundaram, Maheswaran
    Chalmers.
    Hryha, Eduard
    Chalmers.
    Nyborg, Lars
    Chalmers.
    Ahlfors, Magnus
    Quintus Technologies, Västerås.
    Characterisation Of EBM-built Shelled Samples of Ti6Al4V Compacted by HIP2016Conference paper (Refereed)
  • 30. Greenslade, David
    et al.
    Koptyug, Andrey
    Symons, Martin
    Aspects of low-frequency low-field electron spin resonance1995In: Royal Society of Chemistry. Annual Reports on the Progress of Chemistry. Section C: Physical Chemistry, ISSN 0260-1826, Vol. 92, p. 3-21Article, review/survey (Other academic)
  • 31. Grubova, I. Y.
    et al.
    Kozadaeva, M.
    Volkova, A. P.
    Khrapov, D.
    Surmenev, R. A.
    Koptyug, Andrey V.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Vladescu (Dragomir), A.
    Tyurin, A.
    Surmeneva, M. A.
    Process window for electron beam melting of Ti–42Nb wt.%2023In: Journal of Materials Research and Technology, ISSN 2238-7854, Vol. 25, p. 4457-4478Article in journal (Refereed)
    Abstract [en]

    Pre-alloyed β-phase Ti˗42Nb alloy was successfully produced for the first time by E-PBF. The study focuses on the determination of the processing parameter window by varying the beam current, beam speed, layer thickness, and line offset to achieve the defect-free manufacturing of new material with desired properties. Overall, 49 regimes were investigated. The Ti˗42Nb powder were characterized using the DSC/TG, XRD, and SEM/EDX analyses to evaluate its suitability for E-PBF manufacturing. The alloys with the best-built quality fall into the narrow zone between the line energies of 0.30 and 0.34 J/mm. The predicted optimal process parameters were I = 4 mA, v = 700–800 mm/s, h = 100 μm, U = 60 kV, and t = 100 μm. Detailed microstructural characterization was carried out to gain insights into the fundamental mechanisms that govern the behavior of the studied alloys. TEM identified the α'' martensitic phase nucleation occurred preferentially at the β grain boundaries. Un-melted ellipsoidal NbC (∼10 μm) particles were detected with no preferential segregation sites. EBSD revealed coarse microstructures and <001> fiber texture, as well as epitaxial grain growth of columnar grains of about 300 μm. The optimal regime demonstrated a texture composed of a high amount of low aspect ratio grains (50%), which yielded a microindentation hardness of 3.0 GPa and a low elastic modulus of 68 GPa. Hence, these results provide opportunities to design novel alloys to be of interest for biomedical applications. Moreover, this study extends the scope of AM by establishing the process parameter window that yields a material with favorable mechanical properties.

  • 32.
    Grubova, Irina Yu.
    et al.
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, Tomsk 634050, Russia..
    Surmenev, Roman A.
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, Tomsk 634050, Russia..
    Neyts, Erik C.
    Univ Antwerp, NANOlab Ctr Excellence, Dept Chem, PLASMANT Res Grp, B-2610 Antwerp, Belgium..
    Koptyug, Andrey V.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Volkova, Anastasia P.
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, Tomsk 634050, Russia..
    Surmeneva, Maria A.
    Natl Res Tomsk Polytech Univ, Phys Mat Sci & Composite Mat Ctr, Res Sch Chem & Appl Biomed Sci, Tomsk 634050, Russia..
    Combined First-Principles and Experimental Study on the Microstructure and Mechanical Characteristics of the Multicomponent Additive-Manufactured Ti-35Nb-7Zr-5Ta Alloy2023In: ACS Omega, E-ISSN 2470-1343, Vol. 8, no 30, p. 27519-27533Article in journal (Refereed)
    Abstract [en]

    New & beta;-stabilizedTi-based alloys are highly promising forbone implants, thanks in part to their low elasticity. The natureof this elasticity, however, is as yet unknown. We here present combinedfirst-principles DFT calculations and experiments on the microstructure,structural stability, mechanical characteristics, and electronic structureto elucidate this origin. Our results suggest that the studied & beta;Ti-35Nb-7Zr-5Ta wt % (TNZT) alloy manufacturedby the electron-beam powder bed fusion (E-PBF) method has homogeneousmechanical properties (H = 2.01 & PLUSMN; 0.22 GPa and E = 69.48 & PLUSMN; 0.03 GPa) along the building direction,which is dictated by the crystallographic texture and microstructuremorphologies. The analysis of the structural and electronic properties,as the main factors dominating the chemical bonding mechanism, indicatesthat TNZT has a mixture of strong metallic and weak covalent bonding.Our calculations demonstrate that the softening in the Cauchy pressure(C & PRIME; = 98.00 GPa) and elastic constant C &#x305; ( 44 ) = 23.84 GPa is the originof the low elasticity of TNZT. Moreover, the nature of this softeningphenomenon can be related to the weakness of the second and thirdneighbor bonds in comparison with the first neighbor bonds in theTNZT. Thus, the obtained results indicate that a carefully designedTNZT alloy can be an excellent candidate for the manufacturing oforthopedic internal fixation devices. In addition, the current findingscan be used as guidance not only for predicting the mechanical propertiesbut also the nature of elastic characteristics of the newly developedalloys with yet unknown properties.

  • 33. Hemp, John
    et al.
    Sanderson, M. L.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Liang, B.
    Sweetland, D. J.
    Al Rabeh, L. H.
    Problems in the Theory and Design of Electromagnetic Flowmeters for Dielectric Fluids: Part 1: Experimental Assessment of Static Charge Noise Levels and Signal-to-Noise Ratio2002In: Flow Measurement and Instrumentation, ISSN 0955-5986, E-ISSN 1873-6998, Vol. 13, no 4, p. 143-145Article in journal (Refereed)
    Abstract [en]

    This paper reports on experimental measurements of electrode signal noise spectra in an electromagnetic flowmeter designed for

    flow measurement of the dielectric liquid BP180. The design of the flowmeter tube and the detection electronics is described.

    Dependence of the noise spectra on flow rate, electrode dimensions and particle content of the liquid is reported. Implications for

    flowmeter tube design and for the choice of frequency of operation to achieve reasonable signal-to-noise ratios are explained.

  • 34. Hosseini, S. B.
    et al.
    Mallipeddi, D.
    Holmberg, J.
    Rännar, Lars-Erik
    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.
    Sjöström, William
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Krajnik, P.
    Klement, U.
    Comparison of machining performance of stainless steel 316L produced by selective laser melting and electron beam melting2022In: Procedia CIRP, Elsevier, 2022, p. 72-77Conference paper (Refereed)
    Abstract [en]

    Powder bed fusion processes based additively manufactured SS 316L components fall short of surface integrity requirements needed for optimal functional performance. Hence, machining is required to achieve dimensional accuracy and to enhance surface integrity characteristics. This research is focused on comparing the material removal performance of 316L produced by PBF-LB (laser) and PBF-EB (electron beam) in terms of tool wear and surface integrity. The results showed comparable surface topography and residual stress profiles. While the hardness profiles revealed work hardening at the surface where PBF-LB specimens being more susceptible to work hardening. The investigation also revealed differences in the progress of the tool wear when machining specimens produced with either PBF-LB or PBF-EB. 

  • 35.
    Jonsson, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Dual band Fraktal Antenna for RFID Applications2005Conference paper (Refereed)
  • 36.
    Jonsson, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Using Fractals to Obtain Antennas with High DirectivityManuscript (Other academic)
  • 37.
    Jonsson, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Koptoiug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Genetically Engineered Dual band Antenna for RFID Applications2005Conference paper (Refereed)
  • 38.
    Katz-Demyanetz, Alexander
    et al.
    Technion’s R&D Foundation, Israel Institute of Metals, Haifa, Israel.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Popov, Vladimir V.
    Technion’s R&D Foundation, Israel Institute of Metals, Haifa, Israel.
    In-situ Alloying as a Novel Methodology in Additive Manufacturing2020In: 2020 IEEE 10th International Conference Nanomaterials: Applications and Properties", NAP 2020, IEEE, 2020Conference paper (Refereed)
    Abstract [en]

    Additive Manufacturing (AM) of metallic alloys, ceramics and composites often requires a use of prealloyed powders as raw materials. Since synthesizing of such powders is complicated and expensive, an issue of in-situ processing becomes relevant and is increasingly studied nowadays. The main idea of in-situ alloying assisted processing, namely the alloying/reaction occurring between materials of different powders, can be implemented at three principally separate processing stages: pre-processing (raw material preparation), printing itself and post-processing (sintering/infiltration/heat-treatment). The presented brief review gives a necessary background for in-situ alloying at the mostly employed pre-process, process and post-process stages relevant for Powder Bed Fusion (PBF), Direct Energy Deposition (DED) and Binder Jet Printing (BJP) technologies. The presented survey discusses the involved physical processes with their relevance for each mentioned AM technologies and proposes a novel methodology for designing new materials. 

  • 39.
    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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  • 40.
    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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  • 41. Khrapov, D.
    et al.
    Kozadayeva, M.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Mishurova, T.
    Meinel, D.
    Surmenev, R.
    Surmeneva, M.
    Geometrical features and mechanical properties of the sheet-based gyroid scaffolds with functionally graded porosity manufactured by electron beam melting2023In: Materials Today Communications, ISSN 2352-4928, Vol. 35, article id 106410Article in journal (Refereed)
    Abstract [en]

    Functionally graded porous scaffolds (FGPS) constructed with pores of different size arranged as spatially continuous structure based on sheet-based gyroid with three different scaling factors of 0.05, 0.1 and 0.2 were produced by electron beam powder bed fusion. The pore dimensions of the obtained scaffolds satisfy the values required for optimal bone tissue ingrowth. Agglomerates of residual powder were found inside all structures, which required post-manufacturing treatment. Using X-ray Computed Tomography powder agglomerations were visualized and average wall thickness, wall-to-wall distances, micro- and macro-porosities were evaluated. The initial cleaning by powder recovery system (PRS) was insufficient for complete powder removal. Additional treatment by dry ultrasonic vibration (USV) was applied and was found successful for gyroids with the scaling factors of 0.05 and 0.1. Mechanical properties of the samples, including quasi-elastic gradients and first maximum compressive strengths of the structures before and after USV were evaluated to prove that additional treatment does not produce structural damage. The estimated quasi-elastic gradients for gyroids with different scaling factors lie in a range between 2.5 and 2.9 GPa, while the first maximum compressive strength vary from 52.5 for to 59.8 MPa, compressive offset stress vary from 46.2 for to 53.2 MPa. 

  • 42. Khrapov, D.
    et al.
    Kozadayeva, M.
    Manabaev, K.
    Panin, A.
    Sjöström, William
    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.
    Mishurova, T.
    Evsevleev, S.
    Meinel, D.
    Bruno, G.
    Cheneler, D.
    Surmenev, R.
    Surmeneva, M.
    Different approaches for manufacturing ti-6al-4v alloy with triply periodic minimal surface sheet-based structures by electron beam melting2021In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 14, no 17, article id 4912Article in journal (Refereed)
    Abstract [en]

    Targeting biomedical applications, Triply Periodic Minimal Surface (TPMS) gyroid sheet-based structures were successfully manufactured for the first time by Electron Beam Melting in two different production Themes, i.e., inputting a zero (Wafer Theme) and a 200 µm (Melt Theme) wall thickness. Initial assumption was that in both cases, EBM manufacturing should yield the structures with similar mechanical properties as in a Wafer-mode, as wall thickness is determined by the minimal beam spot size of ca 200 µm. Their surface morphology, geometry, and mechanical properties were investigated by means of electron microscopy (SEM), X-ray Computed Tomography (XCT), and uniaxial tests (both compression and tension). Application of different manufacturing Themes resulted in specimens with different wall thicknesses while quasi-elastic gradients for different Themes was found to be of 1.5 GPa, similar to the elastic modulus of human cortical bone tissue. The specific energy absorption at 50% strain was also similar for the two types of structures. Finite element simulations were also conducted to qualitatively analyze the deformation process and the stress distribution under mechanical load. Simulations demonstrated that in the elastic regime wall, regions oriented parallel to the load are primarily affected by deformation. We could conclude that gyroids manufactured in Wafer and Melt Themes are equally effective in mimicking mechanical properties of the bones. 

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  • 43. Khrapov, D.
    et al.
    Paveleva, A.
    Kozadayeva, M.
    Evsevleev, S.
    Mishurova, T.
    Bruno, G.
    Surmenev, R.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-). Tomsk Polytechnic University, Russia.
    Surmeneva, M.
    Trapped powder removal from sheet-based porous structures based on triply periodic minimal surfaces fabricated by electron beam powder bed fusion2023In: Materials Science & Engineering: A, ISSN 0921-5093, E-ISSN 1873-4936, Vol. 862, article id 144479Article in journal (Refereed)
    Abstract [en]

    Electron Beam Powder Bed Fusion-manufactured (E-PBF) porous components with narrow pores or channels and rough walls or struts can be filled with trapped powder after the manufacturing process. Adequate powder removal procedures are required, especially for high-density porous structures. In the present research, sheet-based porous structures with different thicknesses based on triply periodic minimal surfaces fabricated by E-PBF were subjected to different post-processing methods, including a traditional powder recovery system for E-PBF, chemical etching and ultrasound vibration-assisted powder removal. Wall thickness, internal defects, microstructure and morphology features, powder distribution inside the specimens, mechanical properties and deformation modes were investigated. A powder recovery system could not remove all residual powder from dense structures. In turn, chemical etching was effective for surface morphology changes and subsurface layers elimination but not for powder removal, as it affected the wall thickness, considerably influencing the mechanical properties of the whole structure. The ultrasound vibration method was quite effective for the removal of residual powder from sheet-based TMPS structures and without a severe degradation of mechanical properties. Ultrasound vibration also caused grain refinement. 

  • 44.
    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. 

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  • 45.
    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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  • 46. Koptioug, Andrei
    Application of the Time-Variable Feedback to the Input Amplifiers of Pulse Magnetic Resonance Spectrometers: Theoretical Considerations2002In: Applied Magnetic Resonance, ISSN 0937-9347, E-ISSN 1613-7507, Vol. 22, no 22/4, p. 513-537Article in journal (Refereed)
    Abstract [en]

    Analytical model for the optimization of the signal-to-noise (S/N) performance for the receiverwith input resonance circuit and variable feedback is developed. It is shown that by varyingthe feedback type and depth optimization of the receiver the best S/N performance could be achieved.This approach is based upon a resonator-receiver model with lumped elements. These assumptionsare relatively general for the model to be applicable for the design of both continuous and pulsereceivers in radio-frequency and microwave bands. The overall S/N performance of the receiver uponthe noise properties of its elements and the feedback settings in the input amplifier is studied fordifferent parameter settings. It is shown that the separate optimization of individual elements doesnot necessarily lead to the best S/N performance of the receiver, especially when bandwidth propertiesand noise contribution of the elements are substantially different. It is shown that critical couplingof the amplifier to the resonance structure could be far from optimum. In some cases the optimumS/N performance could be achieved with the coupling settings less than critical. But under the assumptionsmade the coupling over the critical value does not correspond to the best receiver S/Nperformance. Suggestions on the optimum architecture of magnetic resonance spectrometer receiverswith variable feedback are made.

  • 47.
    Koptioug, Andrei
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    New Transmission Line Resonators for ESE1998In: EPR Newsletter, Vol. 9, no 3, p. 20-22Article in journal (Other academic)
  • 48.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Antzutkin, Oleg
    Lindgren, M.
    Lund, Anders
    Optically detected ESR (OD ESR) of radical-ion pairs in coloured solutions: Observation of transient Trans-Azobenzene Radical Cation1993In: Applied Magnetic Resonance, ISSN 0937-9347, E-ISSN 1613-7507, Vol. 5, no 1, p. 77-86Article in journal (Refereed)
    Abstract [en]

    Trans-azobenzene dissolved in different liquid hydrocarbons absorbs fluorescence arising from all acceptors previously used in Fluorescence Detected Magnetic Resonance (FDMR) and Optically Detected ESR (OD ESR) spectroscopy making optical detection impossible. In this report a new acceptor,rubrene, having sufficient quantum yield of fluorescence in the red band 550–620 nm, has been proven successful. OD ESR spectra of the radical-ion pairtrans-azobenzene+/rubrene were detected in liquid squalane (2,6,10,15,19,23-hexamethyl-tetracosane) solution in the temperature range 294–243 K. The experimental isotropic hyperfine splittings of the radical cation oftrans-azobenzene (a N=1.4 mT) have been compared with those from MNDO/INDO calculations and with those of earlier work using freon matrix studies.

  • 49.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Mathematics, and Science Education (2023-).
    Body Part Surrogates for Medicine, Comfort and Safety Applications2023In: Advances in 3D Printing / [ed] Sharma, Ashutosh, Rijeka: IntechOpen , 2023Chapter in book (Refereed)
    Abstract [en]

    <i>Advances in 3D Printing</i> presents an overview of various types of advances in 3D printing. It discusses current research trends, problems, and applications of 3D printing processes and materials. The book also discusses advances in bioprinting, tissue generation, radiotherapy, and safety issues in health care. It showcases applications of 3D printing in digital design, body part surrogates, rheological models, airway stents, 3D-printed cermets, and more. It also discusses advances in biomimetic nanocomposite materials, intellectual property concerns, and safety issues in 3D printing technology.

  • 50.
    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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