A Superelastic Gradient Porous NiTi Alloy with Structure and Mechanical Properties Analogy to Human Bones

Porous NiTi shape memory alloys (SMAs) with continuous gradient porosity have been successfully fabricated by low pressure sintering (LPS). The distribution of pores can be controlled by adjusting the original Ni and Ti powders and filling them into mold properly. The mechanical and superelastic properties of continuous gradient porous NiTi SMAs are much superior to that of the step gradient ones, and the average porosity per distance is a key role to affect its superelastic performance. The present preliminary results show that the structures of continuous gradient porous NiTi SMAs are similar to that of human bones and their mechanical properties are higher than that of human bones.