工艺参数对大气等离子喷涂Al_2O_3-40%TiO_2涂层性能影响

The Impact on Performances of Al_2O_3-40%TiO_2 Coating by Atmospheric Plasma Spraying Process

基于涂层的显微硬度、孔隙率和断裂韧性,利用四因素三水平正交试验并结合极差分析方法,对大气等离子喷涂Al2O3-40%Ti O2陶瓷涂层的喷涂电压、喷涂电流、主气流量、喷涂距离等4个工艺参数进行优化。结果表明:4个工艺参数因素相互交错影响着涂层的性能,且喷涂距离对涂层显微硬度影响较大,喷涂电压对涂层的孔隙率、断裂韧性有明显影响,对涂层的综合性能评分影响顺序是:喷涂电流>喷涂距离>主气流量>喷涂电压;优化的最佳工艺参数:喷涂电压为65V,喷涂电流为500A,主气流量为30L/min,喷涂距离为90mm;最优工艺参数制备的涂层显微硬度为1036.73HV0.1,孔隙率为0.9%,断裂韧性为19.87MPa?m1/2,涂层的结合强度为37.8MPa。

Four main parameters including spraying voltage,spraying current,main gas flow rate and spraying distance of atmospheric plasma spraying processing of Al2O3-40%TiO2 ceramic coating were optimized,based on the microhardness, porosity and fracture toughness of coating ,and used the orthogonal test of four factors three levels and range analysis method. The results show that the performances of the coating are mutual crisscross affected by the four parameters factors. The microhardness of coating is great impacted by spraying distance. The porosity and fracture toughness of the coating are significant affected by spraying voltage. The influence sequences of four factors on the comprehensive performance of coating are following：spraying current, spraying distance, main gas flow rate, spraying voltage. The optimized process parameters are spraying voltage of 65V,spraying current of 500A,main gas flow of 30L/min and spraying distance of 90mm. The microhardness of coating by the optimal process parameters is 1036.73HV0.1. The porosity is 0.9%. The fracture toughness is 19.87MPa·m^1/2. The bond strength of coating is 37.8MPa.