为了改善基体与陶瓷涂层物理相容性, 利用半导体激光熔覆技术在不锈钢基体表面制备了CoCrTaAlY涂层作为热障涂层粘结层。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)及能谱仪(EDS)等对CoCrTaAlY涂层的组织、物相和成份等进行分析。结果表明, 当激光功率不变时, 随着扫描速度的增加, 熔覆层厚度和宽度降低而形状系数和润湿角增加; 当扫描速度不变时, 随着激光能量密度的增加, 熔覆层厚度和宽度增加而形状系数和润湿角降低; 熔覆层主要由γ/γ’-(Fe,Al)与颗粒状析出物M(Ta,Si)C组成; 随着温度梯度和冷却速度的增加, 熔覆层内胞状晶转变成树枝晶, 继而生成等轴枝晶。

In order to improve the physical compatibility of the substrate and the ceramic coating, CoCrTaAlY coatings were produced by semiconductor laser cladding technology. The geometrical profiles, microstructure and phase constitutions of the CoCrTaAlY coatings were investigated by X-ray diffraction(XRD)and scanning electron microscope(SEM)with energy dispersive spectrometer(EDS). The results show that, when the laser power is constant, the cladding height and width decrease, while the shape coefficient and wetting angle increase with the increase of the laser scanning speed. However, when the laser scanning speed is constant, the cladding height and width increase, while the shape coefficient and wetting angle decrease with the increase of the laser energy density. CoCrTaAlY coatings are mainly composed of γ/γ’-(Fe,Al)and the precipitated carbides M(Ta,Si)C. Furthermore, when the temperature gradient and the cooling speed increase, the cellular crystals are changed into the dendrites and afterwards the equiaxed dendrites.