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  • 1.
    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.

  • 2.
    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.

  • 3.
    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)
  • 4.
    Ek, Rebecca
    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.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    The Effect of EBM Process Parameters upon Surface Roughness2016In: Rapid prototyping journal, ISSN 1355-2546, E-ISSN 1758-7670, Vol. 22, no 3, p. 495-503Article in journal (Refereed)
    Abstract [en]

    Purpose-The surface roughness of products manufactured using the additive manufacturing (AM) technology of electron beam melting (EBM) has a special characteristic. Different product applications can demand rougher or finer surface structure, so the purpose of this study is to investigate the process parameters of EBM to find out how they affect surface roughness. Design/methodology/approach-EBM uses metal powder to manufacture metal parts. A design of experiment plan was used to describe the effects of the process parameters on the average surface roughness of vertical surfaces. Findings-The most important electron beam setting for surface roughness, accorDing to this study, is a combination of speed and current in the contours. The second most important parameter is contour offset. The interaction between the number of contours and contour offset also appears to be important, as it shows a much higher probability of being active than any other interaction. The results show that the line offset is not important when using contours. Research limitations/implications-This study examined contour offset, number of contours, speed in combination with current and line offset, which are process parameters controlling the electron beam. Practical implications-The surface properties could have an impact on the product's performance. A reduction in surface processing will not only save time and money but also reduce the environmental impact. Originality/value-Surface properties are important for many products. New themes containing process parameters have to be developed when introducing new materials to EBM manufacturing. During this process, it is very important to understand how the electron beam affects the melt pool.

  • 5. Erdegren, M.
    et al.
    Carlberg, T.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Surface Defects Structures on Direct Chill Cast 6xxx Aluminium Billets2011In: Light Metals 2011, John Wiley & Sons, 2011, p. 675-680Chapter in book (Other academic)
    Abstract [en]

    Surface defects found during air-slip direct chill casting are today a major quality factor for extruded aluminum, as they can cause increased segregation, pores and unwanted precipitations. The surface zone in billets of the aluminium alloys 6063, 6005 and 6082 have been analysed by metallographic methods and by chemical analysis. Surface defects, of the type vertical drags, were investigated and compared to defect free surfaces. Inverse segregation to the surface was quantitatively analysed. The concentration profiles were coupled to the appearance of the defects and to microstructures from corresponding areas. It was shown, for vertical drags on 6005 billet surfaces, that either the segregation depth or the precipitated particles were different from surface areas without defects. For the 6063 alloys on the other hand the vertical drag zones contained different particles than surfaces without defects and the segregation had noticeably increased. © 2011 The Minerals, Metals & Materials Society. All rights reserved.

  • 6.
    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.
    Hrhya, Eduard
    Chalmers.
    Nyborg, Lars
    Chalmers.
    Ahlfors, Magnus
    Quintus Technologies, Västerås.
    Characterisation Of EBM-built Shelled Samples of Ti6Al4V Compacted by HIP2016Conference paper (Refereed)
  • 7.
    Jaradeh, Majed
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Carlberg, Torbjörn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Effect of refiner addition level on zirconium-containing aluminium alloys2012In: IOP Conference Series: Materials Science and Engineering, Institute of Physics (IOP), 2012, Vol. 27, p. Art. no. 012008-Conference paper (Refereed)
    Abstract [en]

    It is well known that in aluminium alloys containing Zr, grain refiner additions do not function as desired, producing an effect often referred to as nuclei poisoning. This paper investigates the structure of direct chill-cast ingots of commercial AA3003 aluminium alloys, with and without Zr, at various addition levels of Al5Ti1B master alloy. In Bridgman experiments simulating ingot solidification, Zr-containing alloys were studied after the addition of various amounts of Ti. It could be demonstrated, in both ingot casting and simulation experiments, that Zr poisoning can be compensated for by adding more Ti and/or Al5Ti1B. The results confirm better refinement behaviour with the addition of Ti + B than of only Ti. The various combinations of Zr and Ti also influenced the formation of AlFeMn phases, and the precipitation of large Al 6(Mn,Fe) particles was revealed. AlZrTiSi intermetallic compounds were also detected.

  • 8.
    Jaradeh, Majed M. R.
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Carlberg, Torbjorn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Solidification Studies of 3003 Aluminium Alloys with Cu and Zr Additions2011In: Journal of Materials Science & Technology, ISSN 1005-0302, Vol. 27, no 7, p. 615-627Article in journal (Refereed)
    Abstract [en]

    The effects of Cu and Zr additions, on the microstructure formation, precipitation and ingot cracking, in commercial 3003 Al alloys have been studied. The investigation was carried out by characterizing the grain structure in DC-cast rolling ingots, and studying the solidification microstructure of Bridgman directionally solidified samples. To better understand the influence of the different Cu and Zr contents on the phase precipitations, differential thermal analysis (DTA) experiments were performed. Results from the ingot microstructure analysis show that in commercial alloys with relatively high contents of Cu and Zr, no significant differences in measured grain sizes compared to conventional 3003 Al alloys could be found. However, only Zr containing alloys exhibited significantly larger grain sizes. Increased grain refiner and/or titanium additions could compensate for the negative effects on nucleation normally following Zr alloying. Different types of precipitates were observed. Based on DTA experiments, increased Cu and Zr contents resulted in the formation of Al2Cu phase, and increased solidification range. It was also found that increased Mn content favors an early precipitation of Al(6)(Mn,Fe) giving relatively coarse precipitates. It was concluded that the Cu alloying has a detrimental effect on hot tearing.

  • 9.
    Klingvall Ek, Rebecca
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Electron beam melting: Impact of part surface properties on metal fatigue and bone ingrowth2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abstract

    The aim of this thesis is to investigate aspects on how additive manufacturing (AM) contributes to functional bone implants with the use of the electron beam melting (EBM) technology. AM manufactures parts according to computer-aided design, and the EBM technology melts powder using an electron beam, which acts similar to a laser beam. The topics discussed in this thesis are related to surface roughness that originate from the melted metal powder, and the thesis tries to define some aspects that affect implant functionality. Process parameters steering the electron beam and biocompatibility arising from the surface texture were the initial parts of the PhD studies, and the other half focused on post-processing and fatigue, which are important for medical and industrial applications. There are six studies in this compilation thesis. They are abbreviated as P - process parameters, M - medical applications, and F - fatigue. Studies P, M2, F2, and F3 are journal articles, and M1 and F1 are conference proceedings.

    Study P used design of experiments to investigate how process parameters affect the surface roughness of as-built EBM-manufactured parts and concluded that beam speed and energy (current) were the most important parameters that influence the surface roughness.

    In studies M1 and M2, EBM-manufactured specimens of cobalt-chromium and titanium alloys were used to evaluate biocompatibility. The blood chamber method quantified the reactions of the human whole blood in contact with the metal surfaces, and the results showed how the as-built EBM surface roughness contributed to coagulation and bone healing.

    Rotating beam fatigue equipment was used in studies F1–F3 and study F1 discussed the size effect on fatigue loaded as-built specimens and included specimens with different sizes and with or without hot isostatic pressing (HIP). Study F2 compared as-built and machined specimens and study F3 investigated how Hirtisation, which is a patented electrochemical surface treatment, and HIP affect the fatigue properties that originate from the electrochemical polishing surface topography. The studies showed that a decreased surface roughness increased the fatigue resistance while the stress concentrations (Kt) in the surface of EBM-manufactured specimens decreased.

    The thesis concludes that EBM-manufactured as-built surfaces are suitable for direct contact with the bone, and that HIP does not improve the fatigue resistance of parts with as-built surfaces, where crack initiation starts at notches.

  • 10.
    Klingvall Ek, Rebecca
    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.
    Fatigue properties of electrochemical polished and hot isostatic pressed Ti6A14V manufactured by electron beam meltingIn: Article in journal (Refereed)
  • 11.
    Klingvall Ek, Rebecca
    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.
    Fatigue properties of Ti-6Al-4V manufactured using electron beam melting2017In: Proceedings Euro PM 2017: International Powder Metallurgy Congress and Exhibition 2017, Brussels: EPMA European Powder Metallurgy Association , 2017Conference paper (Refereed)
    Abstract [en]

    The interest in powder bed fusion additive manufacturing methods, such as electron beam melting (EBM), is increasing constantly and main business areas driving the development are aerospace and implant manufacturers. EBM manufactured parts have a rather coarse surface roughness mainly originating from the layer thickness and the powder grains melted by the electron beam. Thus, there is an interest in understanding how the surface properties influences the fatigue performance of the material. In this study, EBM manufactured Ti-6Al-4V was investigated at high cycle fatigue using rotating beam and different types of specimens regarding geometry, as-built and hot isostatic pressing (HIP) post-processing were evaluated. The results confirm that as-built surfaces affect the fatigue limit and a small size specimen geometry for rotating beam fatigue testing is proposed as a part of material and process verification.

  • 12.
    Klingvall Ek, Rebecca
    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.
    Influence of the surface topography of additive manufactured Ti6A14V on fatigue and calculations of the stress concentration factorIn: Article in journal (Refereed)
  • 13.
    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.

  • 14.
    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.  

  • 15.
    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.
    Multiscale surface structuring of the biomedical implants manufactured in Electron Beam Melting technology: Demands, advances and challengesArticle in journal (Refereed)
    Abstract [en]

    Paper discusses the challenges of additive manufacturing when multidimensional shape and surface feature control of the component on wide scale is essential, as it is for the manufacturing of the metallic biomedical implants. Paper also discusses most critical demands imposed by the biomedical implant manufacturing including implant surface roughness issues along with possible solution pathways, and gives some examples of the problems encountered and achievements reached in solving these challenges for the Ti6Al4V EBM®- manufactured components.

  • 16.
    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.

     

  • 17.
    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.

  • 18.
    Leicht, Alexander
    et al.
    Chalmers.
    Shvab, Ruslan
    Chalmers.
    Hrhya, Eduard
    Chalmers.
    Nyborg, Lars
    Chalmers.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Characterization of virgin and recycled 316L powder used in additive manufacturing2016Conference paper (Refereed)
  • 19.
    Leicht, Alexander
    et al.
    Chalmers.
    Vattur Sundaram, Maheswaran
    Chalmers.
    Yao, Yiming
    Chalmers.
    Hrhya, Eduard
    Chalmers.
    Nyborg, Lars
    Chalmers.
    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.
    Frisk, Karin
    Swerea KIMAB.
    Ahlfors, Magnus
    Quintus Technologies.
    As-HIP Microstructure of EBM Fabricated Shell Components2016In: Proceedings of Wolrd PM2016 - AM - Properties of Lightweight Materials ll, 2016Conference paper (Refereed)
    Abstract [en]

    Electron Beam Melting (EBM) was used to build Ti-6Al-4V cylindrical shell samples with different wall thickness filled with powder. Built shell samples were HIPed and the difference in microstructure between the EBM-built walls and densified powder inside the shell components was studied as well as the cohesion between these two regions. Components characterization utilizing LOM and SEM+EBSD indicates that columnar grain growth was consistent before and after HIP in the EBM-built part of the components (walls), whereas the densified material in the center of the component had a fine isotropic microstructure, characteristic for HIPed material. The combination of EBM and HIP is shown to be an attractive way of manufacturing complex-shape full density components for high performance applications, involving shortening of built time in the EBM-processing and lead time in capsule fabrication for HIP.

  • 20.
    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)
  • 21.
    Razaz, Ghadir
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Carlberg, Torbjörn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    On the dissolution Process of Manganese and Iron in Molten Aluminum2019In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 50, no 4, p. 1873-1887Article in journal (Refereed)
    Abstract [en]

    The dissolution of Mn and Fe in liquid Al presents a challenge due to their high melting points and low diffusivity. A literature review reveals that the existing knowledge of the processes involved in the dissolution of both Fe and Mn in liquid Al is rather ambiguous. Thus, this work aimed to obtain more detailed insights into the dissolution behavior of Mn and Fe in various Al melts. The results of the Mn dissolution tests showed that three intermediate phases were involved in the dissolution process, all of which exhibited a smooth interface between Mn and the liquid. These three phases were identified as the γ2, Al11Mn4, and µ phases which grow slowly, penetrating the Mn particles. The results of the Fe dissolution tests showed that in pure Al, the Al5Fe2 phase dominates the dissolution process and penetrates the Fe particles. The addition of Ti into the molten Al alters the intermetallic compound formation by replacing Al5Fe2 by Al2Fe. The addition of Si significantly inhibited the Fe dissolution kinetics. A theoretical approach based on Ficks’ law was used to explain the experimentally obtained Mn and Fe dissolution rates. It showed that the surface area and shape of the additives significantly affected the dissolution processes.

  • 22.
    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. 

  • 23.
    Surmeneva, Maria
    et al.
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Chudinova, Ekaterina
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Syrtanov, M
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Surmenev, Roman
    Tomsk Polytechnic University, Institute of Physics and Technologies, Lenina ave., 30, Tomsk, Russian Federation .
    Investigation of the HA film deposited on the porous Ti6Al4V alloy prepared via additive manufacturing2015In: IOP Conference Series: Materials Science and Engineering, IOP, 2015, Vol. 98, p. Art. no. 012025-, article id 012025Conference paper (Refereed)
    Abstract [en]

    This study is focused on the use of radio frequency magnetron sputtering to modify the surface of porous Ti6Al4V alloy fabricated via additive manufacturing technology. The hydroxyapatite (HA) coated porous Ti6Al4V alloy was studied in respect with its chemical and phase composition, surface morphology, water contact angle and hysteresis, and surface free energy. Thin nanocrystalline HA film was deposited while its structure with diamond-shaped cells remained unchanged. Hysteresis and water contact angle measurements revealed an effect of the deposited HA films, namely an increased water contact angle and contact angle hysteresis. The increase of the contact angle of the coating-substrate system compared to the uncoated substrate was attributed to the multiscale structure of the resulted surfaces.

  • 24.
    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.

  • 25.
    Wikman, Stefan
    et al.
    Fusion for Energy, Barcelona, Spain.
    Cui, Daqing
    Studsvik Nuclear AB, Sweden.
    Shen, James
    Stockholms universitet, Sweden.
    Bin, Qian
    Stockholms universitet, Sweden.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    ON 3D ADDITIVE MANUFACTURING ITER COMPONENTS2013Conference paper (Refereed)
  • 26.
    Wikman, Stefan
    et al.
    Fusion for Energy.
    Shen, Zhijian
    Stockholm University.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Obitz, Charlotta
    Studsvik.
    Öijerholm, Johan
    Studsvik.
    Assessment of additive manufacturing of 316L(N)-IG for In-Vessel components and performance of CuCrZr at coolant water interfaces2015Conference paper (Refereed)
  • 27.
    Zhong, Yuan
    et al.
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Liu, Leifeng
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University.
    Koptyug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Wikman, Stefan
    Fusion for Energy, Torres Diagonal Litoral B3, Barcelona, Spain.
    Olsen, Jon
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University.
    Cui, Daqing
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University.
    Shen, Zhijian
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University.
    Additive manufacturing of 316L stainless steel by electron beam melting for nuclear fusion applications2017In: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 486, p. 234-245Article in journal (Refereed)
    Abstract [en]

    A feasibility study was performed to fabricate ITER In-Vessel components by one of the metal additive manufacturing methods, Electron Beam Melting® (EBM®). Solid specimens of SS316L with 99.8% relative density were prepared from gas atomized precursor powder granules. After the EBM® process the phase remains as austenite and the composition has practically not been changed. The RCC-MR code used for nuclear pressure vessels provides guidelines for this study and tensile tests and Charpy-V tests were carried out at 22 °C (RT) and 250 °C (ET). This work provides the first set of mechanical and microstructure data of EBM® SS316L for nuclear fusion applications. The mechanical testing shows that the yield strength, ductility and toughness are well above the acceptance criteria and only the ultimate tensile strength of EBM® SS316L is below the RCC-MR code. Microstructure characterizations reveal the presence of hierarchical structures consisting of solidified melt pools, columnar grains and irregular shaped sub-grains. Lots of precipitates enriched in Cr and Mo are observed at columnar grain boundaries while no sign of element segregation is shown at the sub-grain boundaries. Such a unique microstructure forms during a non-equilibrium process, comprising rapid solidification and a gradient ‘annealing’ process due to anisotropic thermal flow of accumulated heat inside the powder granule matrix. Relations between process parameters, specimen geometry (total building time) and sub-grain structure are discussed. Defects are formed mainly due to the large layer thickness (100 μm) which generates insufficient bonding between a few of the adjacently formed melt pools during the process. Further studies should focus on adjusting layer thickness to improve the strength of EBM® SS316L and optimizing total building time.

1 - 27 of 27
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