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Porous Titanium Niobium (Ti-6Al-7Nb) are widely found in biomedical applications due to their excellent mechanical characteristics and biocompatibility with human bone. In this study, porous Ti-6Al-7Nb were produced with powder metallurgy process together with space holder technique. Magnesium (Mg) was used as spacer to generate pores with porosity range 20-40 vol.%. The production of porous samples started with the spherical Ti-6Al-7Nb powders with average size of 20 µm were mixed with Mg powders with different weight percentage and Polyvinyl Alcohol (PVA) as binder. The mixtures then were compacted using Hydraulic Hand Press under pressure of 600 MPa with double-ended steel die. The green compacts produced sintered for 2 hours under high purity argon gas atmosphere at temperature 1300°C to remove the Mg. The calculated porosity in range ~25-37 % of sintered samples achieved desired porosity content. Compression test with speed 0.001mm/sec were conducted to figure out the mechanical characterization resulting in Elastic modulus, E in the range ~0.0651-0.9375 GPa and yield strength, σy ~3.9-47.0 MPa which sufficient for implantations with human bone. The sintered samples were observed under Scanning Electron Microscope (SEM) where spherical, interconnected macropores and irregular shape of micropores were identified. [ABSTRACT FROM AUTHOR]

The influence of temperature on the deformation and failure behavior of AZ80 wrought Mg alloy has been examined from 77K to 298K. It is found that the yield strength (YS) and ultimate strength (UTS) are increasing with the temperature decreasing, while the elongation is decreasing especial between 213K and 143K. Based on the mechanical tests, observation of environmental scanning electron microscope (ESEM) and transmission electron microscope (TEM), it is proposed that the alloy deforms mainly by slips and twins, but undergoes different mechanism of cleavage in the range of testing temperature. At T>213K, the alloy ductility is higher because the dislocations could pass through twins but pile up at precipitate phase: Mg17Al12, which causes the crack nucleate. At T<143K, the alloy ductility is lower because the dislocation slip are suppressed greatly and dislocations pile up at twins, and cause crack nucleate and expand along twins quickly. At 143K