等离子喷涂AlSi-ployester封严涂层工艺优化研究

采用AlSi-ployester粉末和PARXAIR-3710等离子喷涂系统制备封严涂层.为使AlSi-ployester等离子喷涂涂层获得优良的涂层性能,选择涂层结合强度为判据,通过正交试验对AlSi-ployester等离子喷涂工艺进行了优化.利用扫描电镜,Axio lmager.A lm金相图像分析系统等手段对涂层形貌和孔隙率进行分析,同时对涂层的硬度、抗热震性能进行了测试.确定优化后的工艺参数为:电弧电流790A.主气流量62.7 L/min,辅气流量5 L/min,喷涂距离100mm.结果表明,电弧电流、主气流量、辅气流量、喷涂距离对AlSi-ployester涂层结合强度具有不同的影响,在优化的喷涂工艺参数条件下,AlSi-ployester涂层结合强度可达6.9MPa,具有较好的硬度和热震性能,可为今后等离子喷涂系统工艺参数的选定提供参考.

Optimization of Process Parameters for AlSi-ployester Coatings Prepared by Plasma Spraying

Abradable seal coating were prepared by AlSi-ployester powder and plasma spraying system(Model PARXAIR-3710).In order to get an plasma sprayed AlSi-ployester coating with good properties,the plasma spraying process was optimized by orthogonal experiment design taking adhesive strength level as criterion.The surface of the coatings and porosity was studied by scanning electron microscopy(SEM)and Axio Imager.A l m metallographic image analysis system,the coatings'microhardness,thermal shock resistance were tested too.The optimized process parameters of the plasma spraying AlSi-ployester coating were:arc current 790 A,primary gas flow rate 62.7 L/min,secondary gas flow rate 5 L/min and spray distancel00 mm.The results show that arc current,primary gas flow rate,secondary gas flow rate,spraying distance have different effects on the adhesive strength of AlSi-ployester coating.The highest adhesive strength (6.9 MPa)of AlSi-ployester coating can be obtained using the optimized parameters.The coating displays good microhardness,themal shock resistanceproperty.This result can be a reference for determining the parameters in plasma spraying process.