研究等离子喷涂相异涂层时间间隔对热障涂层残余应力的影响

张啸寒1，2，冯胜强1，刘　光1，庞　铭2

（1.中国兵器科学研究院宁波分院，浙江　宁波　315103；2.中国民航大学机场学院，天津　300300）

摘　要：为了突破Mo／8YSZ 热障涂层高温易剥离的技术瓶颈，研究等离子喷涂相异涂层的时间间隔对热障涂层残余应力的影响规律，基于热弹塑性有限元理论，利用ANSYS 有限元仿真模拟软件，建立了等离子喷涂Mo／8YSZ 热障涂层的数值模型，模型中考虑了材料不同温度下的热物性参数，分析研究了等离子喷涂黏结底层和陶瓷面层在不同的时间间隔下喷涂构件残余应力分布情况及变化趋势。结果表明，随着喷涂相异涂层时间间隔的增加，喷涂构件的最大轴向残余拉应力呈现逐渐增大的变化趋势，最大轴向残余压应力呈现逐渐减小的变化趋势，最大径向残余应力与最大剪残余应力的变化不明显；基体与涂层界面分布着更多的径向残余压应力，随着喷涂相异涂层时间间隔的增加，径向残余压应力的分布区间增大，且在界面同一位置径向残余压应力逐渐增大；随着喷涂相异涂层时间间隔的增加，涂层的轴向残余拉应力的突变值增大，轴向残余压应力的突变值减小；涂层剥离失效的起始位置出现在相异涂层界面或基体与涂层界面下方0.2～0.4 mm 的区间范围内，且伴随着喷涂相异涂层时间间隔的增加，涂层缺陷的萌发位置逐渐向界面边缘转移。通过调控等离子喷涂相异涂层的时间间隔，可实现喷涂构件的残余应力合理分布，进一步提升基体与涂层的结合强度。

关键词：等离子喷涂；热障涂层；时间间隔；残余应力；数值模拟

中图分类号：TG174.4　文献标志码：A

基金项目：国家重点研发计划（2018YFB1105800）；国家自然科学基金（51705481）；中央高校基本科研业务费资助项目（201909）。

作者简介：张啸寒（1995—），男，硕士研究生，主要从事材料表面改性与再制造技术的研究，E-mail：zxhcauc＠163.com。(www.xing528.com)

Research on the law of influence of the time interval of plasma sprayed dissimilar coatings on the residual stress of Mo／8YSZ thermal barrier coating

ZHANG Xiaohan1，2，FENG Shengqiang1，LIU Guang1，PANG Ming2

（1.China Academy of Ordnance Science Ningbo Branch，Ningbo 315103，China；2.Airport College，Civil Aviation University of China，Tianjin 300300，China）

Abstract：In order to break through the technical bottleneck of Mo／8YSZ thermal barrier coating which is easy to peel off at high temperature，the influence of time interval of different plasma spraying coatings on residual stress of thermal barrier coating was studied，and a numerical model of plasma spraying Mo／8YSZ thermal barrier coating was established based on thermoplastic finite element theory and ANSYS finite element simulation soft⁃ware.The thermal and physical parameters at different temperatures were considered in the model，and the resid⁃ual stress distribution and variation trend of the sprayed components under different time intervals were analyzed.The results show that，with the increase of the time interval of different coating，the maximum axial residual ten⁃sile stress increases gradually，the maximum axial residual compressive stress decreases gradually，and the maxi⁃mum radial residual stress and maximum shear residual stress do not change obviously.More radial residual com⁃pressive stress is distributed at the interface between the substrate and the coating.With the increase of the time interval of different coating，the distribution range of radial residual compressive stress increases，and at the same location of the interface，the radial residual compressive stress gradually increases.With the increase of the time interval of different coating，the sudden value of axial residual tensile stress increases and the sudden value of axi⁃al residual compressive stress decreases.The initial position of coating peeling failure occurs within the range of 0.2～0.4mm below the interface of dissimilar coating or substrate and coating，and with the increase of the time interval between spraying dissimilar coating，the germination position of coating defects gradually transfers to the interface edge.By adjusting the time interval of plasma spraying different coatings，the residual stress distribution of spraying components can be reasonably realized，and the bonding strength of substrate and coating can be fur⁃ther improved.

Keywords：plasma spraying；thermal barrier coating；time interval；residual stress；numerical simulation