Ti-6Al-4V合金表面石墨基粘结固体润滑涂层的高温摩擦学性能  

Tribological Properties of Graphite-based Solid Lubricating Coatings for Ti-6Al-4V Alloy at 500~800℃

作　　者：王伟[1] 彭怡晴 丁士杰 常文娟 高原 王快社[1] WANG Wei;PENG Yiqing;DING Shijie;CHANG Wenjuan;GAO Yuan;WANG Kuaishe(School of Metallurgy Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学冶金工程学院,西安710055

出　　处：《材料研究学报》2023年第6期432-442,共11页Chinese Journal of Materials Research

基　　金：国家自然科学基金(51975450)。

摘　　要：使用石墨作为固体润滑剂、硅酸钠为粘结剂、二氧化硅为填料、去离子水为分散介质,用浆料法在Ti-6Al-4V钛合金表面制备石墨基粘结固体润滑涂层。用球盘式摩擦磨损试验机测试这种涂层在500~800℃的摩擦学性能,使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能谱仪(EDS)以及X射线光电子能谱仪(XPS)等手段分析其物相、显微组织结构、元素组成及其化学态,研究了这种涂层的润滑机理。结果表明:这种石墨基粘结固体润滑涂层在600~700℃的摩擦学性能优异,在660℃其摩擦系数(0.03)和磨损率(0.953×10^(-4) mm^(3)/(N·m))最低。涂层中的熔融硅酸钠与SiO_(2)的协同润滑作用降低了石墨的热损失,在摩擦界面上生成的易剪切的粘性成分减少了摩擦磨损;在摩擦过程中,石墨通过层间剪切和吸附气体产生了良好的润滑性能,SiO_(2)增强了涂层的承载能力和涂层与基体之间的粘结强度,使涂层的耐磨性能提高。Graphite-based solid lubricating coatings were prepared on Ti-6Al-4V substrate by the slurry method with graphite as solid lubricant,silica as filler,sodium silicate as binder and deionized water as dispersion medium.The tribological properties of the coatings were evaluated by a ball-on-disk friction and wear tester at 500~800℃.The microstructure,chemical composition,elements state and phase constituents of the coatings were characterized by X-ray diffractometer(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and X-ray photoelectron spectroscopy(XPS),respectively.The lubrication mechanism of the coating was also investigated.The results show that the coatings have excellent adhesion,anti-friction and anti-wear properties at 600~700℃.The coatings present the lowest friction coefficient(0.03)and wear rate(0.953×10^(-4) mm^(3)/(N·m))at 660℃.At the same time,the co-lubrication of molten sodium silicate and SiO_(2) in the coating reduces the heat loss of graphite,and the shear viscous component generated on the friction interface reduces the friction and wear.In the process of friction,graphite produces good lubrication performance through interlaminar shear and adsorption gas,SiO_(2) enhances the bearing capacity of the coating and the bond strength between the coating and the matrix,so that the wear resistance of the coating was improved.

关 键 词：金属学 石墨 固体润滑涂层 润滑性能 磨损机制 

分 类 号：TH117[机械工程—机械设计及理论]