Processing and characterization of porous SiC/NiTi alloys for biomedical applications

Abstract

NiTi shape memory alloys have attracted significant attention due to their unique shape memory effect, superelasticity, and excellent mechanical performance. In addition, the fact that NiTi alloys have high resistance to cavitation and corrosion makes them ideal candidate materials in advanced tribological and biomedical applications. The NiTi alloy composite reinforced by fine grain-sized SiC particles was successfully fabricated using powder metallurgy process. In this process, elemental Ni-Ti metal powder mixes reinforced with 0, 1, and 5 % SiC particulates were pressed uniaxial and sintered at 1100◦C in an argon atmosphere for 3 h. The effect of the SiC additions on the mechanical properties, porosity degree, and phase formation of the porous NiTi alloys was studied. After characterization, the bioactivity of the SiC/NiTi exposed samples was evaluated in simulated body fluid test. The microstructure characterization and phase identification of the apatite layer formed in SBF on their surface were also evaluated.