The microstructure and properties of Cr/Ni alloying layer after surface alloying treatment induced by continuous scanning electron beam process

Abstract

Abstract The surface alloying of scanning electron beam can improve the microstructure and mechanical properties of steel materials. In this paper, Cr/Ni alloying treatment was performed on 35CrMo alloy structure steel by using continuous scanning electron beam to improve surface performance. The influence of scanning electron beam technology on the structure of alloy layer is studied, and the influence of coating thickness on the structure and properties of the alloying layer is discussed. The results show that the surface of 35CrMo steel is composed of alloying layer, heat affected zone and matrix. The microstructure of the alloying layer is short columnar crystal, equiaxed crystal and acicular martensite. The surface hardness can reach 770HVwhen the coating thickness is 5μm, which is 2 times of the matrix. With the increase of Cr/Ni coating thickness, the surface of sample hardness decreases, and the corrosion resistance of the sample increases.