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The development of a Ti-34Nb-6Sn alloy by the powder metallurgy method, employing two different compaction conditions, A (100 MPa) and B (200 MPa), was carried out. To evaluate the feasibility of the Ti-34Nb-6Sn alloy as an implant biomaterial, microstructural and mechanical characterizations, as well as corrosion susceptibility and ion release tests, were performed. Results indicated microstructures dominated by the presence of β-Ti phase and a lower percentage of α-Ti and Nb phases. The porosity percentage decreased when the compaction pressure increased. Both conditions presented a good match between the elastic moduli of the alloy (14.0 to 18.8 GPa) and that reported for the bone tissue. The Ti, Nb and Sn ions released for both compaction conditions were within the acceptable ranges for the human body. Condition B showed higher corrosion resistance in comparison with condition A. Based on the obtained results, the produced porous Ti-34Nb-6Sn alloys are feasible materials for orthopedic implant applications.

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A B S T R A C TThe mechanical behavior and microstructural evolution of an AA2017 aluminum alloy processed by ECAP with an equivalent simple shear deformation of ∼6 at 200°C were studied. Samples were characterized by means of scanning electron microscopy (SEM-EDS-EBSD), image-assisted by focus ion beam (FIB), Vickers microhardness and X-ray diffraction (XRD) techniques. During the deformation process, the Al 2 Cu precipitates did not get fragmented or re-absorbed in the Al matrix. After the first ECAP pass, at least 50% of grains displayed an ultrafine size. The EBSD analysis showed an increment of the misorientation angle immediately after the first ECAP pass. The macrotexture evolution was explained in terms of the formation of f1: A 1θ * , A θ , Ā θ , A 2θ * , f2: C θ , θ , B θ , Ā θ , A θ , A 1θ * and f3: C θ , B θ , θ , A θ , Ā θ , A 2θ * fibers. The macro-residual stress measurements of the highly deformed samples showed linear sin 2 ψ profiles. The micro and macro-residual stresses were compatible with dislocation rearrangement, in which the annihilation and formation were in quasi-equilibrium. It was found that the highest microhardness value (1176 MPa) and grain refinement (at least 20% of grains showed a size smaller than 100 μm 2 ) appeared after the first extrusion pass. The decrease in hardness, after the second pass and the residual stress stability, could be associated to a dynamic recovery phenomenon.

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