Corrosion behaviour of a superelastic Ni–Ti alloy

Two Ni–Ti alloys, one with relatively higher nickel content, were investigated for general corrosion behaviour. The lower nickel alloy was tested in the fully annealed condition. The higher nickel alloy has been studied in the solution treated as well as aged condition to produce nickel rich precipitates. The results of different electrochemical corrosion tests, such as open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization, performed in 9 g l−1 NaCl solution at 37 °C are reported. Data have been analysed for the corrosion potential, polarization resistance, corrosion current and pitting potential. The observed differences in corrosion behaviour of the materials are discussed.