Microstructures and wear resistance of Ni-based PLA surfacing layer with introducing magnetic field

Ni-based alloy was surfaced on low-carbon steel by plasma arc surfacing under DC transverse magnetic field.The hardness,wear resistance,microstructure and phase constitution of the surfacing layers were investigated via hardness and wear tests as well as SEM,EDS and XRD analysis.The influence of DC transverse magnetic field on the microstructures and wear resistance of the surfacing layer,the shape and amount of the hard phase were systematically studied.Furthermore,preliminary analysis and discussion of the DC transverse magnetic field mechanism were made.The results show that the optimal properties are obtained when surfacing current and magnetic field current matches properly.When the surfacing current is 140 A and the magnetic field current is 2 A,the hardness and the wear loss of surfacing layer are 66.3 HRC and 0.0767 g,separately.At the point,the amount of hard phase is the most and the distribution of hard phase is even,the comprehensive mechanical properties of surfacing layer are enhanced.