Abstract: The nickel-base alloy was deposited on the low carbon steel by plasma arc surfacing with transverse magnetic field.The influence of transverse alternative pulsed magnetic field frequency on microstructure and properties of plasma arc surfacing layer was researched.The hardness, wear resistance and microstructure of surfacing layer at different pulsed magnetic field currents were systematically analyzed by optical electronic microscope, wear test and microscopic hardness test.The results indicated that the transverse alternative pulsed magnetic field can effectively improve the crystal shape in plasma arc surfacing layer and refine crystal grain.With the proper pulsed magnetic field frequency, the optimum effect of electromagnetic stirring can be obtained, the amount of hardening phase in overlay deposit is increased, the growth direction of hardening phase can be controlled and the hardness and wear resistance of the surfacing overlay are improved.