高铬铁基合金等离子熔覆层表面硬度工艺研究

Study on Surface Hardness of Plasma Cladding Layer for High Chromium Iron-Based Alloy

为探究工艺参数对高铬铁基合金等离子熔覆涂层表面显微硬度的影响,以熔覆于Q235钢表面的单道高铬铁基合金硬质涂层为研究对象,开展二次回归正交旋转组合试验。利用Design-Expert 8.0.6分析软件对试验数据进行方差及响应面分析,建立了各因素与涂层表面显微硬度的数学模型,并探究了工作电流、送粉速度和扫描速度对涂层表面显微硬度的显著特性及影响规律,根据多元函数极值理论,确定最优参数组合并进行了试验验证。试验得到的最优参数组合为:工作电流105A,送粉速度14r/min,扫描速度80mm/min,此时涂层表面显微硬度可达到1075.03HV,约是基体材料的7.49倍。该结果可以为高铬铁基硬质涂层表面性能的改善研究提供理论依据。

In order to investigate the effect of process parameters on the surface microhardness of plasma cladding coatings of high chromium iron-based alloy,a single hard coating of high chromium iron-based alloy coated on Q235 steel was studied,and the quadratic regression orthogonal rotation combination test was carried out.Variance and response surface analysis of test data were performed by using the Design-Expert 8.0.6 analysis software.The mathematical model of various factors and microhardness of coating surface were established,and the influence of working current,powder feeding speed and scanning speed on microhardness of coating surface was explored.According to the extremum theory of multivariate functions,the optimal parameter combination was determined and verified by experiment.The optimal parameter combination obtained by the test were working current of 105A,power feeding speed of 14 r/min,scanning speed of 80 mm/min,under the conditions,the surface microhardness of the coating reached 1075.03 HV,which is about 7.49 times that of the substrate material.The results may provide a theoretical basis for improving the surface properties of high chromium iron-based hard coatings.