Effect of Heat Treatment on Corrosion Resistance and Mechanical Properties of Ni-Ga-Fe Ferromagnetic Shape Memory Alloys

The effects of heat treatment at 700 ℃ for 4 h on the corrosion resistance and mechanical properties of Ni-Ga-Fe ferromagnetic shape memory alloys were investigated.Compressive strength and micro-hardness of the alloys were measured by micro hardness tester and multi-function electronic testing machine.The corrosion resistances of the Ni-Ga-Fe alloys before and after the heat treatment was studied by polarization curves in 3.5% NaCl solution.The results showed that the Ni53Ga27Fe20 casting alloys had the highest corrosion resistance at room temperature.The corrosion resistance decreased and the compressive strength increased after the heat treatment of the alloys.Micro hardness of the Ni-Ga-Fe alloys was dependent on the microstructure after the heat treatment.