Effect of nitrogen ion implantation on the structure and corrosion resistance of equiatomic NiTi shape memory alloy

Abstract

To protect the surface of NiTi from corrosion, an ion implantation method was proposed. In the present work, a surface oxidized sample was implanted with nitrogen at energy of 100 keV. The corrosion resistance property was examined by the anodic polarization method in a simulated body fluid (SBF) at a temperature of 37°C and contrasted to non-implanted NiTi samples. The composition and structure of the implanted layers were investigated by XPS. The experimental results from the electrochemical measurements provide an evidence that the nitrogen ion-implantation increases the corrosion resistance of NiTi shape memory alloy.