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Advances in 3D Printing 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.

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.

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.

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

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

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

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.

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

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.

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.

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.

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.

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

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

Present research addresses the issue of skin aging and corresponding skin treatment individualization. Particular research question was on the developing of simplified criterion supporting patient-specific decision on the necessity and intensity of skin treatment. Basing on the published results and a wide pool of experimental data, we have formulated a hypothesis that a difference between biologic and chronologic age can be used as an express criterion of skin aging.

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.

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

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

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

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

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., STII

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

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.

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., Paper accepted, in print

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.

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.

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

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 opti

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

Nanotekhnologii. Razrabotka, Primeneniye - XXI Vek

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)., Conference Paper

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) whi, Conference Paper

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.

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., Sportstech1

In contrast to nonliving systems, all living systems perform homeorhesis. The system state tends to the so-called necessary path, or creode, when the exogenous signals are in a certain system-relevant range. The present work develops the homeorhesis-aware dynamical model for the motion of a single individual (e.g., human). The model allows for the purposeful behaviour of the individual, the creode, the exogenous forces, and the individual-specific sensitivity to their influences. The model also describes the homeorhetic-dysfunction movements. The transparency of the model is such that it allows a physical analogue in the form of electronic circuits. The model is a first step towards the construction of sociologically relevant models for the prediction of human behaviour. It is indispensable for the analyses of dangerous scenarios where the experiments are impossible, for example when predicting the behaviour of panic-stricken crowds in life-threatening situations. The work illustrates the corresponding numerical-simulation results with a series of figures and suggests topics for future research.

Placing fire detectors in a forest is usually associated with powering problems since the sensors do not have access to external power supply and a periodical change of internal batteries is an undesired option. This paper presents an approach where the fire sensor itself, when heated by nearby fire, generates electrical energy to power a radio transmitter. Presented energizing fire sensor is environmentally friendly and can be mass produced at a very low cost. Upon activation the sensor produces enough power necessary to operate most standard radio transmitters depending on what communication system is chosen for operation. The fire detector unit can be deployed from either helicopter or manually from the ground. The sensor can be designed to activate itself at different temperatures to suit different climate zones.,Rough guidelines are given for estimation of attenuation of radio wave propagation in forest areas in order to predict maximum transmit distance.

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.

One of the complex tasks in mass production of RF electronics is printing the communication antenna using electrically conductive ink. For example, this is very common for radio- frequency identification (RFID) tags. Electrical properties of the ink are mostly determined by conductive (e.g. silver) particles mixed into the ink solution and the way they `connect' in the cured ink. It is also desirable to minimise the amount of ink used per antenna, because high-conducting metals like silver used in the ink are rather expensive. Metal-based inks have limited conductivity, so the thicker the cured ink layer will be the better the antenna radiation efficiency can be achieved, but also the higher will be the costs. In the paper, the authors report on the investigations of the possibility of minimising the amount of ink used per antenna. This can be achieved by printing thicker ink layers, where antenna structures are known to have high current density. Two common antenna structures and a dedicated antenna for passive RFID are used in the investigation. The main result of the paper is that radiation efficiency depends primarily on the total amount of ink used for printing the antenna, rather than on the variations of the layer thickness within the antenna structure, VR, STC - Sensible Things that Communicate

In many engineering and biomedical problems there is a need to identify parameters of the systems from experimental data. A typical example is the biochemical-kinetics systems describing oncogenic hyperplasia where the dynamical model is nonlinear and the number of the parameters to be identified can reach a few hundreds. Solving these large-scale identification problems by the local- or global-search methods can not be practical because of the complexity and prohibitive computing time. These difficulties can be overcome by application of the non-search techniques which are much less computation- demanding. The present work proposes key components of the corresponding mathematical formulation of the nonsearch paradigm. This new framework for the nonlinear large-scale parameter identification specifies and further develops the ideas of the well-known approach of A. Krasovskii. The issues are illustrated with a concise analytical example. The new results and a few directions for future research are summarized in a dedicated section.

Many features of living systems prevent the application of fundamental statistical mechanics (FSM) to study such systems. The present work focuses on some of these features. After discussing all the basic approaches of FSM, the work formulates an extension of the kinetic theory paradigm (based on the reduced one-particle distribution function) that exhibits all of the living-system properties considered. This extension appears to be a model within the generalized kinetic theory developed by N. Bellomo and his co-authors. In connection with this model, the work also stresses some other features necessary for making the model relevant to living systems. A mathematical formulation of homeorhesis is also derived. An example discussed in the work is a generalized kinetic equation coupled with a probability-density equation representing the varying component content of a living system. The work also suggests a few directions for future research.