激光工艺对 45 钢表面梯度熔覆层组织性能的影响.

The effects of laser cladding power， scanning speed and cladding materials on the microstructure and wear resistance of the cladded coating on 45# steel were investigated. The results show that the gradient cladded layer is continuous without the defects of crack pores and is metallurgically bonded to the 45# steel matrix.The microstructure of the cladded layer are characterized by dendritic crystals， equiaxed crystals and other rapid solidification structures， which is composed of α-Fe， CrNiFe-C and Cr7C3. The microhardness of the cladded layer is gradient， and the surface hardness of the cladded layer and the transition layer are 7.48GPa and 5.52GPa， respectively， which is 3.74 and 2.76 times of the hardness of the substrate.Therefore， the laser cladding technology can significantly improve the wear resistance of 45# steel. [ABSTRACT FROM AUTHOR]