Fabrication of porous NiTi alloy via powder metallurgy and its mechanical characterization by shear punch method

In this study, Porous NiTi shape memory alloy has been produced by mechanical alloying of the elemental Ni and Ti powders. The compacting process was done at two temperatures (warm and cold press) and then sintering at 980 and 1050°C was performed on the specimens. Microstructure and mechanical prop-erties of the samples were investigated by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction. Moreover, shear punch test (SPT) employed to investigate the effect of compaction pressure and sintering temperature on the mechanical properties of the fabricated samples. It was revealed that warm compaction/sintering resulted in 15% yield stress improvement and 20% ultimate tensile strength (UTS) enhancement with respect to conventionally produced specimens. The proposed approach in this paper seems a step forward towards fulfillment of the demand for heavy load-bearing artificial bone.