Technologie wytwarzania przyrostowego metali (tzw. druku 3D) zrewolucjonizowały przemysł wytwórczy poprzez umożliwienie produkcji obiektów o dowolnej geometrii z szerokiej gamy materiałów, np. stali, lekkich stopów aluminium, tytanu, szkieł metalicznych, a nawet kompozytów metal – ceramika.
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The mechanical properties of additively manufactured (AM) objects often exceed those of castings while properly chosen post-processing technique allows obtaining a surface with roughness required by most industrial applications. However, many companies still do not decide to implement AM technologies in their manufacturing facilities. The biggest barriers which prevent the usage of AM processes in industrial practice are noticed as high costs, unsatisfactory quality of manufactured objects, lack of experience, and a limited range of materials. What are the perspectives for reducing these barriers in the near future and the current possibilities of various AM technologies? How to choose the best metal AM technology for our application? In this article, I will try to answer these and other questions which often appears in industry and academia.
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Post-process modifications in the form of Hot Isostatic Pressing or surface treatment methods such as sandblasting ormachining have been widely used in the case of improving the quality of elements manufactured with the use of EBM (Electron Beam Melting). The corrosion resistance of titanium alloys for medical applications is a key and critical aspect for the use of personalized components as implants, especially when investigating the issue of additive manufacturing. This paper presents the results of research on the influence of HIP processing on the functional properties of the material produced with the use of EBM, considering the aspect of reconstructive medicine. Both the influence of surface modification and the influence of post-process treatment on microstructural, mechanical, and corrosion properties were investigated. A wide range of research has been carried out using scanning and transmission electron microscopy methods, in combination with three-point static bending tests and performing corrosion tests using potentiodynamic polarization and electrochemical spectroscopic impedance (EIS) in Hank‘s solution. The results showed that HIP treatment has a positive effect on the corrosive properties of the material in terms of increased corrosion resistance compared to materials not subjected to this type of post-process treatment. This fact is also related to the change of the alloy microstructure and the change of mechanical properties towards increased plasticity. In the case of the production of personalized implants with the use of EBM, it is worth considering the benefits of the HIP.
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Owing to the possibility of direct processing of CAD models into three-dimensional objects, additive manufacturing (AM) is widely used in the production of individualized bone scaffolds that can lead to perfect restoration of anatomical structures of missing bone tissues. In this work, one of the AM technologies was applied, referred to as Electron Beam Melting (EBM), using Ti6Al4V ELI alloy to produce open-cell structures. Scaffold architecture influences its mechanical properties and is important from the point of view of biological considerations. To optimize mechanical properties, designed geometries were subjected to Finite Element Method analysis and experimental static compression tests. Also, geometric CT analysis of manufactured scaffolds was carried out (geometry deviations up to ± 300 µm). Obtained results have shown that AM can be used to produce Ti6Al4V ELI alloy scaffolds displaying mechanical parameters similar to those of bone tissue (E = 0.45–2.88 MPa). The EBM process affects the microstructure and macrostructural properties of manufactured parts, e.g., through internal porosities present in the material by to unmelted powder particles (internal porosity in range of 1.25–2.25%). To assess the quality and suitability of additively manufactured implants, a multidimensional verification of the impact of the manufacturing process on the properties of the final product was performed.
Electron beam melting(EBM) is a useful technique to obtain high-purity metal ingots. It is also used for melting refractory metals such as tantalum, which require melting techniques employing a high-energy heat source. Drawing is a method which is used to convert the ingot into a wire shape. The required thickness of the wire is achieved by drawing the ingot from a drawing die with a hole of similar size. This process is used to achieve high purity tantalum springs, which are an essential component of lithography lamp in semiconductor manufacturing process. Moreover, high-purity tantalum is used in other applications such as sputtering targets for semiconductors. Studies related to recycling of tantalum from these components have not been carried outuntil now. The recycling of tantalum is vital for environmental and economic reasons. In order to obtain high-purity tantalum ingot, in this study impurities contained in the scrap were removed by electron beam melting after pre-treatment using aqua regia. The purity of the ingot was then analyzed to be more than 4N5 (99.995%). Subsequently, drawing was performed using the rod melted by electron beam melting. Owing to continuous drawing, the diameter of the tantalum wire decreased to 0.5 mm from 9 mm. The hardness and oxygen concentration of the tantalum ingot were 149 Hv and less than 300 ppm, respectively, whereas the hardness of the tantalum wire was 232.12 Hv. In conclusion, 4N5 grade tantalum wire was successfully fabricated from tantalum scrap by EBM and drawing techniques. Furthermore, procedure to successfully recycle Tantalum from scraps was established.
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Background: Moderate to severe facial esthetic problems challenge the surgeons to discover alternate ways, to rehabilitate the patients using customized porous designs. Porous metal implants are available for over 30 years, but the pore architecture, is constantly changing to improve the stability and longevity of the implant. Objective: To evaluate a customized porous implant produced from electron beam melting and to restore the zygomatic functionality. Methods: Two customized zygomatic reconstruction implants-bulk and porous, are designed based on the bone contours and manufactured using state of art-electron beam melting technology. The two designed implants are evaluated based on strength, weight and porosity for the better osseointegration and rehabilitation of the patient. Results: Porous structures due to their light weight, low volume and high surface area provided better specific strength and young's modulus closer to the bone. Microscopic and CT scanning confirmed that the EBM produced porous structures are highly regular and interconnected without any major internal defects. Conclusions: The customized porous implants satisfies the need of lighter implants with an adequate mechanical strength, restoring better functionality and esthetic outcomes for the patients.
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Role of materials in development of rapid-technologies. New materials for Stereo-Litography (SL) method and for Selective Laser Sintering (SLS) method. Extension of materials offer for LaserCusing process. Materials used for Electron Beam Melting (EBM).
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