等离子喷涂热障涂层内孔隙对其隔热性能的影响

Influence of the Porosity on the Thermal Insulation Performance of Plasma Sprayed Thermal Barrier Coating

隔热性能是评价热障涂层的一个重要指标,而涂层内孔隙是影响其热障性能的关键因素之一。为此,基于Abaqus软件,通过Python二次开发建立包含孔隙的热障涂层隔热分析模型,参数化研究了不同孔隙率、孔隙倾斜角度和孔隙横纵比对涂层隔热性能的影响,获得不同孔隙特征参数下陶瓷层的温度场分布特征,并对比分析不同孔隙特征参数下陶瓷层的有效热导率。结果表明:孔隙率增加能显著影响涂层的隔热性能;在0°~180°范围内,随着孔隙倾斜角增加,有效热导率呈现有规律的变化趋势;随着孔隙横纵比增加陶瓷层隔热性能提高。数值模拟结果对下一代先进热障涂层制备工艺参数和结构设计优化具有重要的指导意义。

Thermal insulation performance is an important index for evaluating thermal barrier coatings,and the porosity in the coating is one of the key factors affecting its thermal barrier performance.In this work,the thermal insulation analysis model of thermal barrier coating with pores was established through the secondary development of Python codes based on Abaqus software.The influence of different porosity,pore orientation and pore aspect ratio on the thermal insulation performance of the coating was investigated base on parameterization strategy,and the temperature field distribution features of the ceramic layer under different pore characteristic parameters were obtained.In addition,the effective thermal conductivity of the ceramic layer under different pore characteristic parameters was compared and analyzed.Results showed that the increase of porosity could significantly affect the thermal insulation performance of the coating.In the range of 0°~180°,as the pore orientation increased,the effective thermal conductivity presented a regular trend of change.Furthermore,as the aspect ratio of the pores increased,the thermal insulation performance of the ceramic layer increased.The numerical simulation results had the important guiding significance for the optimization of the advanced thermal barrier coating process preparation process parameters and structure design used in the next generation.