采用同轴送粉与压片预置激光熔覆工艺制备NiCoCrAlY涂层, 对两种激光熔覆工艺粉末利用率、涂层稀释率、熔覆层硬度及熔覆层微观组织形貌进行了比较。结果表明, 在涂层界面能形成良好冶金结合的优选工艺参数条件下, 同轴送粉激光熔覆粉末利用率和加工参数密切相关, 最高不超过0.4, 而压片预置激光熔覆粉末利用率高于0.9; 同轴送粉激光熔覆制备涂层熔合区为垂直于界面的柱状晶, 上部为均匀的等轴晶, 压片预置激光熔覆涂层的枝状晶贯穿整个涂层; 但是压片预制熔覆涂层的硬度略低于同轴送粉熔覆涂层。

Coaxial powder feeding and squash presenting are used in laser cladding NiCoCrAlY coatings, powder utilization ratio, hardness, dilution ratio and the cladding layer coating microstructure morphology are compared. The results show that under the condition that the coatings form a good metallurgical bonding interface with preferred process parameters, the coaxial powder feeding laser cladding powder utilization ratio are no more than 0.4 and closely related to processing parameters, while the squash presenting laser cladding powder utilization ratio are greater than 0.9; there are columnar crystals perpendicular to the interface in Coaxial powder feeding laser cladding coating fusion zone, and the upper part are full with equiaxed crystals, as the dendrites throughout the coating formed by squash presenting laser cladding. And the hardness of squash presenting laser cladding coating is lower than coaxial powder feeding laser cladding coating slightly.