CuCo_2Be合金等离子体喷涂Cr_3C_2-NiCr涂层的冷热疲劳寿命及失效机理  

Thermal shock resistance of Cr_3C_2-NiCr coating on copper alloy surface prepared by plasma spraying

作　　者：王春蕊 李惠[2] 李建生[2] 何昌林[2] 张文芮 

机构地区：[1]中海油能源发展装备技术有限公司工程设计研发中心,天津300000 [2]江苏科技大学先进焊接技术省级重点实验室,江苏镇江212003

出　　处：《材料热处理学报》2016年第10期179-185,共7页Transactions of Materials and Heat Treatment

基　　金：江苏省教育厅高校自然基金(2014CL061J);兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室开放课题

摘　　要：采用等离子喷涂技术在CuCo_2Be合金表面制备Cr_3C_2-NiCr涂层,通过正交试验确定了CuCo_2Be合金表面等离子喷涂的最优工艺,并对在最佳工艺参数下喷涂的试样,选择在500℃进行高温热震试验,对热震过程中喷涂试样的失效过程进行了跟踪和失效机理研究。研究表明,涂层组织呈现明显的层状,Cr_3C_2-NiCr化合物为角状,涂层与界面的结合以机械结合为主,涂层含有一定量的非晶相。高温热震失效后的涂层中存在铜、镍的氧化物,高温失效主要源自涂层与基体的热应力与氧化过程。Coatings of Cr3C2-NiCr coating on CuCo2Be alloy was prepared by plasma spraying technique,and the optimal process parameters of the plasma spraying were determined by orthogonal experiment.The thermal shock resistance of the coatings at 500 ℃ and its failure mechanism were examined.The results show that the layered Cr3C2-NiCr coatings with Cr3C2 particles in NiCr matrix are observed,and the bonding of the coating and substrate is mainly mechanical bond.Copper and nickel oxide are detected in the coatings after high temperature thermal shock tests.The failure mechanism of the Cr3C2-NiCr coatings by the thermal shock is attributed to the the thermal stress caused by the difference of thermal expansion coefficients of the coatings and substrate combined with the oxidation of the coatings.

关 键 词：等离子喷涂 CR3C2-NICR涂层 高温热震 失效机理 

分 类 号：TG174.44[金属学及工艺—金属表面处理]