Study on surface alloying of 38CrMoAl steel by electron beam

TiN/Ni alloying of 38CrMoAl steel surface was carried out by continuous scanning electron beam. The effect of electron beam process parameters on the surface microstructures and mechanical properties of 38CrMoAl steel was studied. The results shows that the sample surface was divided into three regions: alloying layer, heat affected zone and substrate. Alloying layer made up with equiaxed crystals and short columnar crystals, microstructure of the heat affected zone was acicular and lath martensite, microstructure of substrate was tempered sorbate. The microhardness of the sample section first increased and then decreased, at a depth of 400 μm, the microhardness reached a maximum of 817.9 HV. When the beam current reached 12 mA and the moving speed reached 5.5 mm/s, the surface microhardness of the sample reached the highest 1209HV and the abrasion loss reached the lowest 4.6 mg.