司太立合金等离子弧堆焊工艺参数对焊层稀释率的影响

Effect of technology parameters on rate of dilution of Stellite coating deposited by plasma arc surfacing

采用正交试验方法,分析了等离子弧堆焊主要工艺参数对司太立合金堆焊层稀释率的影响,采用光学显微镜观察了堆焊层的组织,并用硬度计测试了堆焊层的硬度。结果表明,等离子弧堆焊工艺参数中对堆焊层稀释率影响程度按大小排序依次为送粉量、转移弧电流及堆焊速度。最优参数为送粉量31 g/min,转移弧电流142 A,堆焊速度151 mm/min,在此工艺参数下试焊得到的堆焊层稀释率为2.2%,堆焊层组织为胞状和树枝状的α-Co基固溶体加枝晶间的碳化物,表面硬度达到HV440左右。

The effect of process parameters on dilution rate of Stellite coating deposited by plasma arc surfacing was studied by orthogonal test method. Microstructure and hardness of the coatings were investigated using optical micrograph and vickers hardness tester. The results showed that the effect degree of main process parameters on dilution rate had been ranked: powder feeding rate >transferred arc current >spray welding speed. The optimum parameters: powder feeding rate was 31 g/min, transferred arc current was 142 A, spray welding speed was 151mm/min. The rate of dilution of Stellite coating deposited by optimum process was 2.2%. The typical microstructure of the coating consist of celluar structure and dendrites of α-Co, in the solid solution phase, with interdendritic carbides. The surface hardness was about HV440.