Laser cladding of NiTi wire on AISI 316 stainless steel

Abstract

Nickel titanium (NiTi) wire was clad on AISI 316 stainless steel using a high-power CW Nd:YAG laser under various processing parameters. The effect of the laser parameters on the morphology of the melt pool and the hardness of the clad were studied using SEM and Vickers microhardness measurement. The dilution of the clad due to mixing with substrate and the phases formed were determined by EDS and XRD analysis, respectively. The elastic behavior of the clad was investigated by nanoindentation and compared with that of NiTi wire. With proper laser processing parameters, good fusion bonding was observed. However, a dilution ratio of more than 10 % was common in the clad. The hardness was increased from 400 HV for the NiTi wire to more than 800 HV for the clad, but was accompanied with some degradation in superelasticity. The present study indicates feasibility of cladding NiTi wire on AISI 316 stainless steel, though the achievement of a lower dilution ratio requires further work.Nickel titanium (NiTi) wire was clad on AISI 316 stainless steel using a high-power CW Nd:YAG laser under various processing parameters. The effect of the laser parameters on the morphology of the melt pool and the hardness of the clad were studied using SEM and Vickers microhardness measurement. The dilution of the clad due to mixing with substrate and the phases formed were determined by EDS and XRD analysis, respectively. The elastic behavior of the clad was investigated by nanoindentation and compared with that of NiTi wire. With proper laser processing parameters, good fusion bonding was observed. However, a dilution ratio of more than 10 % was common in the clad. The hardness was increased from 400 HV for the NiTi wire to more than 800 HV for the clad, but was accompanied with some degradation in superelasticity. The present study indicates feasibility of cladding NiTi wire on AISI 316 stainless steel, though the achievement of a lower dilution ratio requires further work.