等离子喷涂Al_(2)O_(3)涂层与高硬配副的摩擦学性能研究  

Study on Tribological Properties of Plasma Thermal Spraying Al_(2)O_(3) Coating Sliding against Counterparts with High Hardness

作　　者：李荣泽 赵晓琴[2] 段文山[1] 安宇龙[2,3] 周惠娣 陈建敏[2,3] LI Rong-ze;ZHAO Xiao-qin;DUAN Wen-shan;AN Yu-long;ZHOU Hui-di;CHEN Jian-min(School of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070,China;State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]西北师范大学物理与电子工程学院,兰州730070 [2]中国科学院兰州化学物理研究所固体润滑国家重点试验室,兰州730000 [3]中国科学院大学材料与光电研究中心,北京100049

出　　处：《表面技术》2021年第9期184-195,共12页Surface Technology

基　　金：国家自然科学基金(51975556,42065005)。

摘　　要：目的研究大气等离子喷涂Al_(2)O_(3)涂层在高硬配副下的摩擦磨损行为。方法通过大气等离子喷涂(APS)制备了厚度约为380μm的Al_(2)O_(3)涂层,利用纳米压痕仪测量了Al_(2)O_(3)涂层和两种摩擦副的硬度和弹性模量。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)对喷涂粉末、涂层以及磨痕的相结构和形貌进行了表征分析,通过X射线能量色散谱仪(EDS)分析了涂层磨痕中对偶元素的转移。另外,还通过CSM摩擦机系统地研究了该涂层的摩擦磨损行为。借助X射线光电子能谱仪(XPS)分析了磨痕中的化学组成。结果制备的Al_(2)O_(3)涂层主要以γ-Al_(2)O_(3)相为主,且存在一定孔隙,并出现层状结构。在摩擦实验中发现,在同一摩擦副下,Al_(2)O_(3)涂层的摩擦系数随着载荷的增加而逐渐降低,磨损率随之增大。由于摩擦配副力学性能的差异,使Al_(2)O_(3)涂层表现出不同的摩擦磨损行为。以Si_(3)N_(4)为摩擦副时,Al_(2)O_(3)涂层的摩擦系数较小,但磨损率大,磨损机制主要是磨粒磨损和粘着磨损。在摩擦过程中,Si_(3)N_(4)对偶副会与空气中的水反应,生成少量具有润滑效果的Si(OH)4胶体。以WC为摩擦副时,Al_(2)O_(3)涂层的摩擦系数大,但磨损率低,磨损机制主要是粘着磨损和磨粒磨损,并伴有疲劳磨损。在摩擦过程中,由于产生了摩擦热,Al_(2)O_(3)涂层磨痕表面的γ-Al_(2)O_(3)相转变为α-Al_(2)O_(3)相,摩擦配副的硬度和弹性模量越大,摩擦系数越高,γ-Al_(2)O_(3)相的转变也越多。结论因高硬度的Si_(3)N_(4)和WC对偶球拥有不同的力学性能,对大气等离子喷涂制备的Al_(2)O_(3)涂层的摩擦磨损机理有显著的影响,并且在摩擦过程中,涂层磨痕内的γ-Al_(2)O_(3)相会向α-Al_(2)O_(3)相转变。This paper aims to study the friction and wear behavior of Al_(2)O_(3)coating with atmospheric plasma spraying under high hardness.The Al_(2)O_(3)coating was prepared by atmospheric plasma spraying(APS)with a thickness of 380μm.Besides,the phase structure and morphology of the powder and as-sprayed coating were characterized by X-ray diffractometer(XRD)and scanning electron microscope(SEM).The X-ray energy dispersive spectrometer(EDS)was employed to analyze the transfer of grinding crack elements,while Al_(2)O_(3)coating and two kinds of hardness and elastic modulus of friction pair were measured with the help of the nano indentation apparatus.In addition,the friction and wear behavior of the coating was systematically studied by the CSM friction machine.The chemical composition of the wear marks was analyzed by X-ray photoelectron spectroscopy(XPS).The Al_(2)O_(3)coating was mainly composed ofγ-Al_(2)O_(3)phase,with a large number of pores and layered structure.In the friction experiment,it is found that under the same friction pair,the friction coefficient of Al_(2)O_(3)coating decreased gradually with the increase of load,and the wear rate increased.Due to the differences in mechanical properties of friction pairs,Al_(2)O_(3)coatings exhibited different frictional wear behaviors.When the friction pair was Si_(3)N_(4),the friction coefficient of Al_(2)O_(3)coating was small,but the wear rate was large.The friction mechanism was mainly abrasive wear and adhesive wear.At the same time,Si_(3)N_(4)reacted with water in the air to form Si(OH)4 colloid with lubricating effect during the friction process.When the friction pair was WC,the friction coefficient was large,but the wear rate was low.The friction mechanism was mainly adhesive wear and abrasive wear,accompanied by fatigue wear.Theγ-Al_(2)O_(3)phase inversion occurred in Al_(2)O_(3)coating on the surface of wear trace due to friction heat.The higher the friction coefficient was,the greater the hardness and elastic modulus of the friction pair was,and the mo

关 键 词：Al_(2)O_(3)涂层 大气等离子喷涂 摩擦学性能 Si_(3)N_(4)对偶球 WC对偶球 

分 类 号：TH117.1[机械工程—机械设计及理论]