H13钢表面激光熔覆铁基合金粉末的工艺研究

Research on the Process of Laser Cladding Iron-Based Alloy Powder on H13 Steel Surface

为探究H13钢表面激光熔覆铁基合金粉末试验中工艺参数对熔覆层表面硬度和几何尺寸的影响规律并得出最佳工艺参数,试验对不同数值的激光功率、扫描速度和送粉电压所得单道熔覆层进行了表面硬度测量、显微组织观察和显微硬度测量等分析。结果表明,当扫描速度和送粉电压一定时,激光功率增加会使得熔池深度和熔覆层厚度增加,表面硬度则会先增加后降低;当扫描速度和激光功率一定时,送粉电压增加会使得熔池深度和熔覆层高度变化,表面硬度则先增加后降低。通过对峰值对应的熔覆层进行金相组织观察发现,熔覆层晶粒细小且排列紧密,并与基体形成了良好的冶金结合。熔覆层截面显微硬度分布表明,其熔覆层的平均显微硬度明显高于基体。

In order to investigate the law how process parameters influence surface hardness and geometrical size of the cladding layer in the test of laser cladding Fe based alloy powder on H13 steel, the surface hardness, microstructure observation and micro hardness of the single pass cladding layer with different values of laser power, scanning speed and powder feeding voltage were analyzed in this test. The results show that when the scanning speed and the powder feeding voltage are constant, the laser power increases, the depth of the molten pool and the thickness of the cladding layer will increase, and the surface hardness will increase first and then decrease; when the scanning speed and laser power are constant, the powder feeding voltage increases, the depth of the molten pool and the height of the cladding layer will change, and the surface hardness will increase firstly and then decrease. By the microstructure observation of the peak corresponding cladding layer, the grain size is small and the arrangement is close, and it forms a good metallurgical bond with substrate. The micro hardness distribution of the cladding layer cross section shows that the average micro hardness of the cladding layer is significantly higher than that of the substrate.