Silver additions influence on biomedical porous Ti-Ni SMAs fabricated by microwave sintering

Abstract

Ti-Ni and Ti-Ni-Ag shape memory alloys (SMAs) were prepared by microwave sintering. In Ti (49 -%Ag)-Ni51-Ag (atomic percentage), the silver was added with three percentages of (0.246, 0.5 and 1.51) at. %, respectively. The influence of Ag addition on the microstructure, phase composition, transformation temperatures and mechanical properties were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC) and compression test. The microstructure shows needles and plates inside Ti-rich region. The R phase appears at the plane (-112) and the plane (300). This phase has appeared during cooling and heating of the baseline of DSC test. The compression strain at maximum strength was improved, while the compression strength was reduced. The highest compressive strain was for the sample with 0.246 at. % Ag. The elastic modulus decreases with the increasing of Ag content. The elastic modulus of these alloys was low that make it proper for biomedical applications such as natural human bone due to the sintering method and also improve by adding silver.