【摘要】 利用CO2激光器在45钢基体上熔覆Ni基合金,分析激光熔覆层的微观组织,测试其显微硬度及磨损性能。结果表明,所制得熔覆层组织致密、无裂纹,与基体形成良好的冶金结合。从熔覆层表层到基体热影响区,组织呈现出由细小的树枝晶→胞状晶、树枝晶→平面晶过渡。激光熔覆层磨损量约为基体的1/3,熔覆层耐磨能力增强的主要原因在于熔覆层与基体良好的冶金结合,以及基体与涂层元素固溶强化和碳化物等析出相的强化作用所致。更多还原

【Abstract】 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.更多还原