| Porous NiTi alloy was prepared using elemental powder sintering methodin this study. Porous NiTi alloy can not only keep the excellent mechanicalproperties of bulk NiTi but also has its bionic advantages in biomedical field.Optical-microscope, scan electron-microscope(SEM) and X-ray diffraction(XRD) were used to study the effects of the process on the properties of thefinal samples and determine appropriate process. Compression, bending,hardness and wearing tests were carried out to evaluate the mechanicalproperties of the porous NiTi alloy. Differential thermal analysis(DTA) wasconducted to characterize the phase transition. Electrochemical test and atomicabsorption spectrum(AAS) were introduced to demonstrate the corrosionbehavior. The results show that: Under a condition of 100MPa, 990℃,8h, the phases, pores and othercharacters of the sample could much meet the requirement of implant. Heattreatment could make the phases evener and has an important effect on SME. Obvious stress-plat was not found on the compressive stress-strain curve.The rupture behavior of porous NiTi alloys had a brittle character. After heattreatment, the compression strength revealed a lower value; the corrosionresistance and wear resistance of porous NiTi alloys were worse than bulkones and the wear rate-load curve had a distinct difference from bulk ones. 100% shape recovery of porous NiTi alloy wasn't attained even under asmall deformation; shape recovery could be increased by thermal-mechanicalcircling, but it decreased with circle times; DTA curves of the porous NiTialloy had a broader thermal peak. The thermal peak became narrower afterheat treatment. Corrosion resistance was declined due to the pores of porous NiTi alloy.
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