| 摘要: |
| CrN 和 CrAlN 涂层以其优异的力学性能可作为汽车发动机运动部件的保护性涂层使用,然而它与常用润滑油添加剂的相互作用仍需要进一步的研究。 采用磁控溅射技术制备氮化铬(CrN)和氮化铬铝(CrAlN)涂层,利用 X 射线衍射和纳米压痕研究涂层的微结构和机械性能,考察常用摩擦改进剂-烷基二硫代氨基甲酸钼(MoDTC)对涂层摩擦学性能的影响,并通过电子扫描电镜和 X 射线光电子能谱技术等表征探究 MoDTC 的减摩作用机制。 结果表明:与 CrN 涂层相比,CrAlN 涂层结构致密,晶粒细化,机械性能更好。 在添加质量分数为 1%的 MoDTC 后的 PAO 基础油润滑下,表现出更优异的减摩抗磨性能。 对磨痕表面的 XPS 分析表明,在边界润滑条件下,钢/ CrN 和钢/ CrAlN 摩擦运动过程中 MoDTC 均发生化学降解反应,生成一层含二硫化钼(MoS2 )的润滑膜,且后者产生的 MoS2 含量更高,因而表现出更优的摩擦学性能。 研究结果对延长汽车发动机的使用寿命具有指导意义。 |
| 关键词: CrN CrAlN MoS2 MoDTC 摩擦学性能 化学降解 |
| DOI：10.11933/j.issn.1007-9289.20210804002 |
| 分类号:TG174;TH117 |
| 基金项目:国家自然科学基金(51975304)；山东省自然科学基金(ZR2019MEE016)； 2018 年工业强基工程(TC180A3Y1)资助项目 |
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| Tribological Properties of CrN and CrAlN Coatings in the Presence of Organic Molybdenum Additives |
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FU Xiaojing1,2, LI Ruichuan2, LI Yang3, WAN Yong2,4
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1.School of Mechanical and Automotive Engineering, Qingdao University of Technology, Qingdao 266033 , China;2.School of Mechanical and Automotive Engineering, Qilu University of Technology, Jinan 250353 , China;3.Yellow River Institute Limited of Frontier New Materials Research, Taiyuan 030000 , China;4.State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences, Lanzhou 730000 , China
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| Abstract: |
| Chromium nitride (CrN) and chromium aluminum nitride (CrAlN) have been used as the protective coatings for sliding parts in automotive engine. However, the more research is needed to investigate the interaction of CrN and CrAlN coatings with common used lubricating additives. CrN and CrAlN coatings are deposited by magnetron sputtering technology. The microstructure and mechanical properties of CrN and CrAlN coatings are studied by X-ray diffraction technique and nano-indentation, respectively. The tribological performance of CrN and CrAlN coatings under lubrication of molybdenum dialkyldithiocarbate (MoDTC) are investigated. The action mechanism of MoDTC is investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that CrAlN coating has denser structure, smaller grains and better mechanical properties than CrN coating. Moreover, as compared with CrN coating, CrAlN coating presents better friction-reducing and wear protection performance when lubricated by PAO+ 1wt%MoDTC. XPS analysis of the wear scar indicate that tribochemical degradation of MoDTC occurred during the sliding movement of steel / CrN and steel / CrAlN tribopairs under boundary conditions, forming a tribofilm containing molybdenum disulfide ( MoS2 ). A higher content of MoS2 is found on CrAlN than CrN coating, leading to the better tribological performance. The research results are of great significance to prolong the service life of automobile engine. |
| Key words: CrN CrAlN MoS2 MoDTC tribological properties tribochemical degradation |
