Microstructure and wear-resistance property of laser cladding Ni-based alloy

Laser cladding of Ni-based alloy on 45 steel substrate was carried out by CO2 laser.The microstructure,microhardness,and wear resistance of the laser cladding layers were analyzed and tested.The results show that the cladding layers have compact and flawless microstructure,and form a metallurgical bond with 45 steel substrate.Microstructure of cladding zone consists of fine dendritic crystal,cellular crystal and plane crystal from the surface of cladding layers to heat-affected zone of 45 steel substrate.The wear resistance of the laser cladding layers is 3 times than that of the unclad 45 steel.The main reasons of the abradability improvement are good metallurgical bonding of the cladding with substrate,and strengthening due to solid solution and precipitation hardening from carbonide.