油溶性有机钼添加剂作用下微弧氧化改性TC4钛合金的摩擦学性能  

Tribological Properties of Micro-Arc Oxidized TC4 Titanium Alloy under the Action of Oil-Soluble Organic Molybdenum Additives

作　　者：栾俊吉 高建国 曹磊 万勇 李瑞川[1] LUAN Junji;GAO Jianguo;CAO Lei;WAN Yong;Li Ruichuan(School of Mechanical and Automotive Engineering,Qilu University of Technology,Shandong Jinan 250353,China;School of Mechanical and Automotive Engineering,Qingdao University of Technology,Shandong Qingdao 266033,China;Qingdao Dagang Customs,Shandong Qingdao 266011,China;State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Gansu Lanzhou 730000,China)

机构地区：[1]齐鲁工业大学机械与汽车工程学院,山东济南250353 [2]青岛理工大学机械与汽车工程学院,山东青岛266033 [3]青岛大港海关,山东青岛266011 [4]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,甘肃兰州730000

出　　处：《摩擦学学报》2022年第2期294-304,共11页Tribology

基　　金：国家自然科学基金(51975304);山东省自然科学基金(ZR2019MEE016)项目资助。

摘　　要：借助微弧氧化技术在TC4钛合金表面构筑了高硬度氧化物薄膜,利用X射线衍射仪(XRD),扫描电子显微镜(SEM)及拉曼光谱等手段对膜层结构进行了分析,考察了二烷基二硫代氨基甲酸钼(MoDTC)作为聚α烯烃PAO6润滑添加剂对微弧氧化薄膜的摩擦学性能的影响.结果表明:经过微弧氧化处理后得到的钛合金试样展现了优异的减摩抗磨性能,与未处理的TC4样品相比,在含质量分数为2%MoDTC的PAO6油润滑下,摩擦系数降低了87.4%,磨损率下降了3个数量级.这主要是因为经微弧氧化处理后,TC4钛合金表面形成的TiO_(2)薄膜具有较高硬度与耐磨性,同时促进了MoDTC添加剂在边界润滑条件下的摩擦化学反应,在接触区表面生成含有MoS_(2)的润滑层.Titanium and its alloy have been introduced into automobile manufacturing due to their excellent mechanical properties and relatively low density.However,titanium alloy has poor tribological performance even with efficient lubrication.Thus,surface engineering is widely used to enhance the wear protection properties of titanium alloys.In this paper,high hardness oxide films were constructed on the surface of TC4 titanium alloy by means of micro-arc oxidation(MAO)technology in electrolyte contacting silicate and phosphate.The structure of the MAO coatings was analyzed by X-ray diffraction,scanning electron microscopy,and Raman spectroscopy.XRD patterns of the MAO coatings suggest a layer of titanium oxide in the form of rutile and anatase on the TC4 substrate after the MAO process.MAO-treated TC4 substrate was characterized by the typical morphology,i.e.,a uniform distribution of pores of different sizes on the surface.The MAO coatings possessed higher hardness than the TC4 substrate.The tribological experiments were conducted to test the tribological properties the MAO treated TC4 under lubrication of PAO base oil containing molybdenum dialkyldithiocarbamate(MoDTC)additive,a commonly used friction modifier.It was found that the addition of MoDTC to the base oil did not significantly change the friction performance of untreated TC4,suggesting that MoDTC was not effective in reducing the friction coefficient for the bare TC4.However,this was not the case for the TC4 samples after the MAO treatment.Specifically,the friction coefficient of the MAO-coated TC4 sample lubricated with the base oil was stable at 0.11 during the entire sliding period.After the addition of 2%MoDTC to the base oil,the friction coefficient was further reduced to~0.05 after a short running-in period,suggesting best matching effort for the surface MAO coatings with MoDTC additive.XPS analysis results implied that a large amount of MoS_(2) as well as MoO_(3) and MoS_(2) was found on the wear track,and a small amount of metallic molybdenum was eve

关 键 词：微弧氧化 TC4钛合金 MODTC 边界润滑 TiO_(2) 

分 类 号：TH117.3[机械工程—机械设计及理论]