ZL102合金表面激光熔覆Al-Si+Al2O3复合涂层的组织和磨损性能

采用5 kW横流CO2激光器，在ZL102合金表面熔覆Al2O3颗粒增强的Al-Si合金复合涂层，探索了激光熔覆工艺参数对涂层质量的影响，分析了涂层的微观组织，测试了涂层的硬度和磨损性能。结果表明，在优化工艺参数下可以获得连续均匀、无气孔和裂纹的涂层，涂层的组织是在α固溶体和α固溶体+Si共晶的基体上均匀地分布着Al2O3颗粒，Al2O3颗粒尺寸在10～20 μm之间，与涂层基体结合紧密。涂层与基材之间呈典型的外延生长界面，形成了良好的冶金结合。涂层的硬度在Hv190～260之间，比基材提高了约2倍，涂层的耐磨性能比基材提高了约4倍。

Microstructure and Wear Resistance of Al-Si+Al2O3Composite Layer on ZL102 Alloy by Laser Cladding

Laser cladding of Al-Si+Al2O3 composite layer on ZL102 alloy was performed by 5 kW CO2 laser. The effect of the laser cladding parameters to layer was investigated. The analysis on the microstructure, the hardness and wear resistance of laser cladding layer shows that, the Al-Si+Al2O3 layer is uniform, continuous and free of pores and cracks by optimized parameters. Al2O3 particles disperse in the matrix of α-Al and α-Al+Si eutectics with particle size of 10～20 μm. The interface between the layer and the substructure was epitaxial, with excellent bonding by the strong metallurgical interface. The hardness and wear resistance of laser cladding layer is about 2 times (in the range of Hv 190～260) and 4 times higher than that of the substrate, respectively.