等离子喷涂法制备高温吸波涂层时的热应力模拟  

Thermal Stress Simulation of Preparation of High-Temperature Absorbing Coating by Plasma Spraying Method

作　　者：赵志雄 李洋 罗发[1] 张刘超[1] 李鹏 张瑞端 阮兴翠 段世昌 ZHAO Zhixiong;LI Yang;LUO Fa;ZHANG Liuchao;LI Peng;ZHANG Ruiduan;RUAN Xingcui;DUAN Shichang(State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an 710072,Shaanxi;Shaanxi Huaqin Technology Industry Co.,Ltd.,Xi’an 710119,Shaanxi)

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]陕西华秦科技实业股份有限公司,陕西西安710119

出　　处：《火箭军工程大学学报》2024年第6期78-90,共13页Journal of Rocket Force University of Engineering

基　　金：国家科技重大专项(J2019-VI-0015-0130)。

摘　　要：为研究吸波涂层制备过程中应力随涂层厚度的演变以及涂层沉积完毕最终冷却至室温的应力分布情况,以堇青石高温吸波材料为研究对象,采用等离子喷涂法,在GH536基体表面制备了高温吸波涂层。利用ANSYS有限元分析软件建立了涂层的沉积过程模型,模拟计算了涂层逐道沉积时的温度场和涂层沉积过程中不同喷涂厚度时的应力场。采用数值模拟研究涂层制备过程中应力的变化规律。结果表明:处在火焰中心位置的涂层温度更高,模拟计算得到的温度场与实际喷涂工作情况温度场吻合良好;首层喷涂完毕后,涂层表面产生条带状张应力,在喷涂路径的中间产生更大的热应力;随着喷涂厚度的增加,涂层中间部分应力变小,边缘部分保持较大应力;冷却至室温后,涂层表面中间部分应力降至300 MPa,边缘部分应力为550 MPa,结合界面中间和边缘部分的应力分别为180、550 MPa,这表明涂层在喷涂结束冷却至室温时,边缘受到更大的张应力,更容易发生开裂及翘曲。In order to study the variation of stress along with coating thickness during the preparation of the absorbing coating and the stress distribution of the coating after deposition and cooling to room temperature,a high-temperature absorbing coating was prepared on the surface of GH536 matrix by plasma spraying method with cordierite.Then,a model of the deposition of the coating was established by ANSYS finite element analysis software.Thereby,temperature fields at different deposition stages and stress fields of the coating with different spraying thick-nesses during the deposition were simulated and calculated.Furthermore,the variation law of stress during coating preparation was studied by numerical simulation.Results showed that the temperature of the coating at the center of the flame is higher,and the temperature field calculat-ed by the proposed simulation model is in good agreement with that of the actual spraying work-ing.After the first layer is sprayed,banded tensile stresses are generated on the surface of the coating,which leads to creating greater thermal stresses between spraying paths.As the coating thickness increases,the stress in the middle part of the coating becomes smaller,and the edge part retains a big stress.After cooling to room temperature,the stress of the middle part of the coating surface is reduced to 300 MPa while that of the edge part is 550 MPa.Simultaneously,for the joint interface,the stress of the middle part is 180 MPa,and the stress of the edge part is 550 MPa.It indicates that when the coating cools to room temperature after the spraying,the edge is subjected to greater tensile stress,which is more prone to crack and warp.

关 键 词：等离子喷涂 高温吸波涂层 有限元分析 残余应力 

分 类 号：TG178[金属学及工艺—金属表面处理]