Effect of sintering temperature on microstructure and mechanical properties of TiNi alloy

Porous titanium-nickel(TiNi) shape memory alloy(SMA) with homogeneous pore distribution and good mechanical properties was fabricated by pure element powders sintering process.Effect of sintering temperature on microstructure and mechanical properties of TiNi alloy was studied by X-ray diffraction(XRD),metallurgical microscope,scanning electron microscopy(SEM) analysis and electronic universal testing machine at 900,950,1000,1050,1100 or 1150℃.The results showed that sintering temperature is the determinants affecting the properties of porous TiNi alloy,then phase composition,pore characteristic and mechanical properties are improved by change of sintering temperature.With the increase of the temperature from 900 to 1150℃,secondary phase disappeared and phase composition is more homogeneous.The relative density values of porous TiNi increases from 59% to 62%.Tensile strength values increases from 72.43 to 160.12MPa,and elastic modulus values increases from 1.08 to 1.32GPa.