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Over the last decade, advances in additive manufacturing have allowed to obtain complex 3D porous lattice in materials suitable for orthopedic applications. Whereas 3D‐melted titanium alloys have been extensively investigated, little is the current knowledge on the feasibility of bone‐replicating CoCr porous scaffolds manufactured via selective laser melting (SLM). Moreover, the effect of topography on bone cells viability and proliferation has not been fully explored yet. Small cylindrical porous lattices were modeled from micro‐CT images of human trabecular bone, and from the repetition of spherical‐hollow and body‐centered cubic unit cells, and manufactured via SLM from CoCr powder. Macro‐ and microcharacterization of the porous samples were assessed using optical microscope, micro‐CT, and SEM. The scaffolds mechanical properties, measured via ISO testing, compared well with those of the human bone. Osteoblast‐like cells proliferation and viability were assessed in vitro, and compared to those cultured on a standard nonporous implant‐to‐bone interface, showing steady increase on all geometries over time. SEM analysis confirmed the quality of cells morphology, spread, and organization on all lattices. The SLM process appeared not to alter the biocompatibility of CoCr; however, 15–100 μm irregularities and macroalterations were observed in the porous scaffolds with respect to the 3D nominal models. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2343–2353, 2019.

Microstructure and material flow of aluminum alloys have a significant influence on the mechanical properties and surface quality. In extrusion of aluminum billets at high temperatures the microstructure is dependent on the alloy and the forming and temperature history. A prediction of grain size and precipitation is of increasing importance in order to design the process by adjustment of parameters such as punch speed, temperatures, and quenching. To give references for microstructure prediction based on material flow, and with it strain and strain rate history, this paper deals with the microstructure during the extrusion process of AA6060, AA6082, and AA7075 alloys. Billets have been partly extruded to axisymmetric round profiles and the microstructure of the press rests consisting of the billet rests in container and die has been considered. Furthermore, these rests have been analyzed to show the material flow, dynamic and static recrystallization based on macro etchings and visible microstructure under different conditions, e.g. as in the area of high strain rate near the container wall, or in dead zones [I]. To allow an accurate simulation of the extrusion process, punch force and temperature conditions during the tests have been measured and are presented in this paper, too.