NiCoCrAlYTa/Ag/Mo复合自润滑涂层的制备及其高低温循环摩擦学性能  

Preparation of NiCoCrAlYTa/Ag/Mo composite self-lubricant coating and its high-low temperature cycling tribological properties

作　　者：郝恩康 陈杰[1] 刘光[1] 崔烺[1] 王晓霞 魏连坤 安宇龙[2] HAO Enkang;CHEN Jie;LIU Guang;CUI Lang;WANG Xiaoxia;WEI Liankun;AN Yulong(Chinese Weapons Science Academy Ningbo Branch,Ningbo 315103,Zhejiang,China;State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000,China)

机构地区：[1]中国兵器科学研究院宁波分院,浙江宁波315103 [2]中国科学院兰州化学物理研究所固体润滑国家重点实验室,兰州730000

出　　处：《航空材料学报》2023年第4期45-54,共10页Journal of Aeronautical Materials

基　　金：国家自然科学基金(52205223);内蒙古自治区自然科学基金(2022QN05019);宁波市自然科学基金(2022J316)。

摘　　要：为了开发适用于苛刻工况的长寿命、高可靠的自润滑涂层,选择NiCoCrAlYTa作为黏结相,Ag作为润滑相,Mo作为增强相,采用超音速火焰喷涂(high-velocity oxy-fuel spraying,HVOF)技术在Inconel718高温合金基体上制备复合涂层。考察该复合涂层在室温及800℃循环交变条件下的摩擦学行为,研究磨损表面的形貌特征、化学成分、相组成,揭示摩擦过程中元素之间的相互作用以及摩擦表面的物理化学本质,探究其在高低温交变环境下的多循环“自适应”润滑机理。结果表明:复合涂层致密均匀,力学性能良好,主要有γ-Ni,β-NiAl,γ′-Ni_(3)Al,Ag和Mo等物相;复合涂层表面生成的β-Ag_(2)MoO_(4)类层状润滑剂,可大大改善涂层在高温条件下的摩擦磨损性能;在多循环交变条件下,复合涂层后续循环摩擦因数较首次循环而言有所增大,但在室温条件下的磨损率却有所减小;这是涂层在高温条件下生成的β-Ag_(2)MoO_(4)类层状尖晶石润滑相与Al2O3、MoO3硬质相氧化物在摩擦剪切力的作用下相互影响而导致的。In order to develop a self-lubricating coating with long life and high reliability suitable for harsh working conditions,the composite coating with NiCoCrAlYTa as matrix phase,Ag as lubricant phase and Mo as the reinforcing phase were prepared by high-velocity oxy-fuel spraying(HVOF)technology.The high-low temperature cycling tribological properties of the composite coating were investigated at 25℃ and 800℃.The morphology features,chemical composition and phase structure of the worn surface were studied to reveal the interaction between different elements in the friction process and physicochemical nature of friction interface.In addition,the multi-cycles adaptive lubrication mechanism under the alternating environment of high and low temperature was explored as well.The results show that the composite coating is dense and uniform,and has better mechanical properties.The phases of the composite coating mainly containγ-Ni,β-NiAl,γ'-Ni_(3)Al,Ag and Mo.Theβ-Ag_(2)MoO_(4) layer-like lubricant generated on the surface can greatly improve the friction and wear performance of the composite coating at high temperature.Under the condition of multi-cycles,the friction coefficient of subsequent cycle of the composite coating is increased compared with the first cycle,but the wear rate of the composite coating at room temperature is decreased.This is caused by the interaction between the lubricating phase of β-Ag_(2)MoO_(4) and the hard phases of Al_(2)O_(3) and MoO_(3) with the action of frictional shear force.

关 键 词：复合涂层 类层状结构 自适应润滑相 热循环 摩擦磨损 

分 类 号：TG174.442[金属学及工艺—金属表面处理]