Corrosion resistance of NiTi after nitrogen, oxygen, and hydrogen plasma immersion ion implantation

Corrosion resistance of NiTi was investigated by implanting Nitrogen, Oxygen and Hydrogen into polished NiTi samples by means of plasma immersion ion implantation (PIII). In both the electrochemical and dissolution tests the simulated body fluid at a pH of 7.4 and the saline solutions at pH of 2.4 and 10.0 were used. It was observed that both the N and O-implanted NiTi samples exhibited significant improvements in the simulated body fluid at a pH of 7.4 with respect to the corrosion resistance. It was also observed that both the nitrogen and oxygen implanted samples possessed better corrosion resistance than the hydrogen implanted ones.