用同步送粉的方式进行青铜母材表面激光熔覆625和1 025-40两种镍基合金粉末的试验。分别用不同激光熔覆参数和不同熔覆材料进行熔覆试验, 通过对熔覆层形貌、裂纹、显微组织、硬度的测试, 评价青铜表面不同熔覆材料和不同激光工艺参数对熔覆层性能的影响。通过熔覆层组织、硬度的测试和渗透探伤, 得到不同激光工艺参数和熔覆材料系对熔覆层组织性能的影响效果, 并对不同激光熔覆工艺参数下熔覆层的宏观和微观质量进行对比分析。获得了青铜母材表面激光熔覆625最佳激光熔覆工艺参数, 即在激光功率为2 000W, 光斑直径为38 mm, 扫描速度为550 mm/s的工艺条件下, 得到的熔覆层表面平整, 组织均匀, 显微硬度高, 稀释率小, 与母材实现良好的冶金结合。

The work aims to optimize the powder material and cladding process by laser on bronze surface and further improve the performance of the cladding layer. Firstly the nickel-base alloy powder 625 and 1 025-40 were cladded using laser on the surface of the bronze base by simultaneous powder feeding. Cladding layer surface properties such as morphology, crack, microstructure and hardness were investigated by way of experiment with different laser cladding parameters and different cladding materials. The effects on the properties of the cladding layer were evaluated at different cladding materials and different laser process parameters.Then, the influence relationship between different laser processing parameters and different cladding materials on the microstructure and properties of the cladding layer were analyzed by means of microstructure, hardness test and penetration test of the cladding layer, and the macroscopic and microscopic features of the cladding layer under different laser cladding process parameters were explored. The cladding layer quality was compared and analyzed in order to obtain the best cladding material and laser cladding process parameters. The results showed that with process parameters such as the laser power of 2 000 W, spot diameter of 38 mm, and scanning speed of 550 m/s, the 625 powder resulting cladding layer was smooth, uniform in structure, high micro-hardness, low dilution rate, and achieved metallurgical bonding with the base metal.