The Procedure For Cladding CuSi3 On 30CrMnSi Steel Surface With CMT Technology

Aim to application of Cu cladding layer in the fields of aviation, spaceflight and weapons manufacturing, a cladding of CuSi3 was cladded on the surface of 30CrMnSi steel. In this paper, on basis of analyzing the influnce of cladding parameters on the temperature field, the interfacial structure, the cladding structure and its formation mechanism, the dilution ratio of cladding layer and the mechanical property were studied primarily and systematically.Based on the comprehensive analyses of heat transfer behavior in the cladding process, a new model of heat source was presented by using the physical dimensions of the cladding layer. In the model, the heat transfer was simulated by a segment column heat source and a Gaussian distribution surface heat source. The results showed that with the increase of feeding speed or the decrease of welding speed, the highest temperature of the cladding metal and the base metal rose, the cooling rate and the temperature gradient of the cladding metal decreased and the quantity of molten base metal rose. The simulation results was verified by comparison of the thermal cycle curves and molten zones between calculated results and experimental results and the predicted results by the model introduced in this paper were in good agreement with the experimental ones.The interface and the cladding layer were analyzed by means of SEM, EDAX and XRD and the formation mechanism of cladding structure was studied with the calculated results . The results showed that the interface was comprised of Fe3Si,α-Fe andε-Cu. With the increase of feeding speed, the compound of Fe and Si was replaced byα-Fe solid solution and the grain changed from cellular dendritic grain to dendritic grain and equiaxed grain. With the increase of welding speed, the compound of Fe 3 Si was replaced by Fe2Si and the grain changed from dendritic grain to cellular dendritic grain. The fast cooling rate of cladding metal led to the separation of Fe and Cu and the formation of Fe-rich particles. The radius of the Fe-rich particles rose and the quantity rose and then decreased with the increase of feeding speed.The dilution ratio of cladding layer was obtained through the molten area of base metal and the shear experiment was carried out on the joints. The results...