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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。
NiCoCrAlY coatings were prepared by coaxial powder feeding and tableting pre-laser cladding. The utilization ratio of the two laser cladding powders, the coating dilution rate, the hardness of the cladding layer and the microstructure of the cladding layer were compared . The results show that under the optimum process parameters of good metallurgical bonding at the coating interface, the utilization rate of co-axial powder laser cladding is closely related to the processing parameters, the maximum does not exceed 0.4, and the pre-laser cladding powder The rate is higher than 0.9; coaxial powder feeding laser cladding coating fusion zone is perpendicular to the interface columnar crystals, the upper part of the uniform equiaxed crystal, prelaminated laser clad coating dendrite throughout the coating ; However, the hardness of the pre-cast cladding coating is slightly lower than that of the coaxial powder coating.