Corrosion behavior of ion implanted NiTi shape memory alloy thin films

In this paper, the corrosion behavior of NiTi thin films implanted with argon, carbon and nitrogen ions was investigated by potentiodynamic scanning (PDS) and electrochemical impedance spectroscopy (EIS) methods. PDS results showed that the icorr was decreased after implantation with carbon and nitrogen and increased with argon ions. EIS measurements also indicated that the corrosion resistance (Rp) of the films implanted with carbon and nitrogen was increased and with argon implantation decreased. Scanning electron microscopy (SEM) images showed a lesser amount of corrosion defects in nitrogen and carbon implanted thin films and more amounts in argon implanted and unimplanted film surfaces. The cracks are also observed on argon implanted surface.

► The corrosion behavior of ion implanted NiTi thin film was studied EIS and PDS methods.
► The corrosion resistance was improved after implantation with carbon and nitrogen ions.
► The corrosion resistance of NiTi films was declined after argon ion implantation.