La_(2)Zr_(2)O_(7)–8YSZ双陶瓷层热障涂层活塞热–机耦合应力分析  

Thermal Mechanical Coupling Stress Analysis of A Piston with La_(2)Zr_(2)O_(7)–8YSZ Double Ceramic Layer Thermal Barrier Coatings

作　　者：林旭[1,2] 陈为欢 代鹏[2] LIN Xu;CHEN Weihuan;DAI Peng(School of Civil and Transportation Engineering,Qinghai Minzu University,Xining 810007,China;State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China;Jiangling Motor Company,Nanchang 330006,China)

机构地区：[1]青海民族大学土木与交通工程学院,西宁810007 [2]天津大学内燃机燃烧学国家重点实验室,天津300072 [3]江铃汽车股份有限公司,南昌330006

出　　处：《内燃机工程》2023年第4期101-108,共8页Chinese Internal Combustion Engine Engineering

基　　金：青海省自然科学基金项目(2022-ZJ-757)。

摘　　要：以某车用发动机活塞为研究对象,基于有限元法建立La_(2)Zr_(2)O_(7)–8YSZ双陶瓷层热障涂层活塞模型,研究陶瓷面层、底部陶瓷层、基体的热–机耦合应力及其双陶瓷层结构对活塞基体的影响。根据温度场分析,陶瓷面层厚度为0.15 mm时,La_(2)Zr_(2)O_(7)–8YSZ涂层活塞基体、陶瓷面层、底部陶瓷层的最高温度分别是271℃、438℃、363℃。随着陶瓷面层厚度增加,活塞基体温度降低,活塞顶面温度升高。热应力分析表明无涂层活塞的最大热应力出现在环槽处,最大值是64 MPa,而涂层活塞基体的最大热应力出现在燃烧室喉口及其顶部边缘部分。受机械负荷影响,无涂层活塞和涂层活塞基体耦合应力最大值均出现在销座处,陶瓷面层和底部陶瓷层最大热–机耦合应力出现在各自底面。随着陶瓷面层厚度增加,陶瓷面层和底部陶瓷层最大耦合应力缓慢减小,活塞基体耦合应力基本不变。Taking the piston of an automotive engine as the research object,the model of a pistion with La_(2)Zr_(2)O_(7)–8YSZ double ceramic layer thermal barrier coatings was established based on the finite element method.The thermal-mechanical coupling behaviors of the ceramic surface layer,bottom layer,substrate,as well as the influence of double ceramic layer on the piston were studied.The results showed that when the thickness of ceramic surface layer was 0.15 mm,the maximum temperatures of La_(2)Zr_(2)O_(7)–8YSZ coating piston substrate,ceramic surface layer,and bottom ceramic layer were 271 ℃,438 ℃,and 363 ℃,respectively.With the increase of the ceramic surface layer thickness,the temperature of the piston substrate decreased while the temperature of the piston top surface increased.The maximum thermal stress of the uncoated piston was 64 MPa,which appeared in the ring groove,while the maximum thermal stress of coated piston substrate appeared in the top edge and the throat of combustion chamber.Due to the effects of the mechanical load,the maximum coupling stresses of uncoated piston and coated piston substrate appeared at the pin seat.The maximum thermal stresses of ceramic surface layer and bottom ceramic layer appeared at the bottom.With the increase of the ceramic surface layer thickness,the maximum coupling stresses of ceramic surface layer and bottom ceramic layer decreased slowly,and the coupling stress of piston substrate remained constant.

关 键 词：活塞 双陶瓷层结构 温度场 热应力 耦合应力 

分 类 号：TK422[动力工程及工程热物理—动力机械及工程]