基于正交试验设计的等离子喷涂8YSZ热障涂层的制备

Preparation of plasma-sprayed 8YSZ thermal barrier coatings under orthogonal test design

为了探究工艺参数之间的耦合作用对涂层微观组织、力学性能的影响规律,基于正交试验,采用大气等离子喷涂技术制备8YSZ热障涂层。结果表明,等离子喷涂8YSZ涂层为层状结构,层间为细小的柱状晶结构;涂层是由t-ZrO_(2)和少量的m-ZrO_(2)相组成,喷涂工艺参数的改变对涂层物相几乎没有影响。喷涂工艺参数对热障涂层结合强度和孔隙率的综合影响顺序为:喷涂距离>喷涂功率>主气流量。喷涂距离为110 mm、功率为30 kW、主气流量为45 L/min是正交实验优化出的最佳喷涂工艺参数,该实验参数条件下,等离子喷涂8YSZ热障涂层的平均结合强度为18 MPa,孔隙率为11.14%。

In order to explore the coupling effect of spraying process parameters on microstructure and mechanical properties of coating,8YSZ thermal barrier coating was prepared by atmospheric plasma spraying technology.The results show that the plasma-sprayed 8YSZ coating is layered with fine columnar crystal structure between layers.The coating is composed of t-ZrO_(2)and a small amount of m-ZrO_(2)phase.The change of spraying parameters has no obvious effect on the phase composition.The comprehensive effect of spraying parameters on bonding strength and porosity of thermal barrier coatings is in the order of spraying distance>power>main gas flow.The average bonding strength and porosity of 8YSZ thermal barrier coatings are 18 MPa and 11.14%with the best spraying process parameters optimized by orthogonal experiment,among which spraying distance is 110 mm,power is 30 kW and maingas flow is 45 L/min.