The EPMA Keynote Papers for Euro PM2018 are:
Tailor-made Functional Composite Components Using AM and HIP
Dipl-Ing Sebastian Riehm
RWTH Aachen University IWM, Germany
The combination of Additive Manufacturing (AM) and Hot Isostatic Pressing (HIP) offers great potential for industrial applications. Skillfully connecting AM and HIP creates a manufacturing process that unites the advantages of both processes. We demonstrate a production route for composite components by AM + HIP. A capsule made of wear-resistant or corrosion-resistant steel is additively manufactured by Laser-Powder Bed Fusion (LPBF). Before building the geometry of the capsule is optimized by FEM simulation to obtain a desired shape. In a second step the capsule is filled with structural steel powder and sealed in a conventional powder HIP process. The capsule remains on the component as an outer layer. In this way a complex-shaped functional net shape composite component is produced. The composite components created by this route are characterized by metallographic investigations.
Development of Ti-Nb And Ti-Nb-Fe Beta Alloys from TiH2 Powders
Ing Chirico Caterina
Universidad Carlos III de Madrid, Spain
Ti-Nb β alloys are a promising alternative as an implant material due to their good properties and low Young’s modulus compared to other Ti-alloys currently employed as biomaterials. In this study three materials of the Ti-Nb and Ti-Nb-Fe systems were produced by powder metallurgy techniques starting from TiH2 (TH) powder. Several sintering cycles were employed to evaluate the H2 elimination and the effect of sintering temperature on densification and fraction of β-Ti phase. Also the influence of alloying element size using two kinds of Fe powder was evaluated. The highest loss of H2 was achieved decreasing heating rate at the temperature range of hydride decomposition. SEM images and XRD results show mainly a β-Ti phase for TH40Nb and TH5Fe25Nb samples. The TH12Nb sample shows (α+β) microstructure. Fe addition with smaller particle size seems to improve the diffusion of Nb into Ti what promotes a higher β-phase fraction and sample homogeneity.
Four-dimensional (4D) Observation of Ductile Fracture in Sintered Iron Using Synchrotron X-ray Laminography
Prof Dr Ozaki Yukiko
Kyushu University, Japan
Synchrotron X-ray laminography was used to reveal the time evolution of the three-dimensional (3D) morphology of micropores in sintered iron during a tensile test. 3D snapshots showed networked open pores growing wider than 20 µm along the tensile direction resulting in internal necking of the specimen. Finally these pores initiated cracks perpendicular to the tensile direction by coalescing with surrounding preexisting microvoids or secondary-generated voids immediately before fracture. Topological analysis of the barycentric positions of these microvoids showed that they formed two-dimensional networks within a ~20 µm-radius area. This indicates that microvoid coalescence could occur on shear planes formed close to the enlarged open pores or between closed pores by strain accumulation and play an important role in crack initiation.
EPMA Keynote Paper Awards winners for Euro PM2018
Left to right: Mr Philippe Gundermann (EPMA President), Ing Caterina Chirico (Universidad Carlos III de Madrid, Spain), Prof Dr Yukiko Ozaki (Kyushu University, Japan), Dipl-Ing Sebastian Riehm (RWTH Aachen University IWM, Germany) and Euro PM2018 TPC Co-Chair Prof Herbert Danninger
© Andrew McLeish Euro PM2018