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有机钼添加剂作用下CrN和CrAlN涂层的摩擦学性能∗

  • 付小静1,2

    机 构：

    1. 青岛理工大学机械与汽车工程学院 青岛 266033

    2. 齐鲁工业大学机械与汽车工程学院 济南 250353

    ×
  • ， 李瑞川2

    机 构：

    2. 齐鲁工业大学机械与汽车工程学院 济南 250353

    ×
  • ， 李阳3

    机 构：

    3. 黄河前沿新材料研究院有限公司 太原 030000

    ×
  • ， 万勇2,4

    机 构：

    2. 齐鲁工业大学机械与汽车工程学院 济南 250353

    4. 中国科学院兰州化学物理研究所固体润滑重点实验室 兰州 730000

    ×

1. 青岛理工大学机械与汽车工程学院 青岛 266033；
2. 齐鲁工业大学机械与汽车工程学院 济南 250353；
3. 黄河前沿新材料研究院有限公司 太原 030000；
4. 中国科学院兰州化学物理研究所固体润滑重点实验室 兰州 730000；

Tribological Properties of CrN and CrAlN Coatings in the Presence of Organic Molybdenum Additives

  • FU Xiaojing1,2

    Affiliation：

    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

    ×
  • ， LI Ruichuan2

    Affiliation：

    2. School of Mechanical and Automotive Engineering, Qilu University of Technology, Jinan 250353 , China

    ×
  • ， LI Yang3

    Affiliation：

    3. Yellow River Institute Limited of Frontier New Materials Research, Taiyuan 030000 , China

    ×
  • ， WAN Yong2,4

    Affiliation：

    2. School of Mechanical and Automotive Engineering, Qilu University of Technology, Jinan 250353 , China

    4. State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 , China

    ×

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；

作者简介:

付小静,女,1990年出生,博士研究生。主要研究方向为硬质涂层及润滑材料、薄膜材料的减摩和耐磨性能。E-mail:1205454198@qq.com

万勇(通信作者),男,1968年出生,博士,教授,博士研究生导师。主要研究方向为润滑材料及摩擦学。E-mail:wanyong@qlu.edu.cn

中图分类号:TG174;TH117

文献标识码:A

DOI:10.11933/j.issn.1007-9289.20210804002

参考文献 1
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目录contents

    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。

    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.

    关键词

    CrN ； CrAlN ； MoS2 ； MoDTC ； 摩擦学性能 ； 化学降解

  • 0 前言

  • CrN硬质涂层具有良好的力学性能和摩擦学性能,在刀具、航空航天等领域中有广泛的应用背景, 特别是CrN涂层表面具有高质感、大晶粒尺寸的特征,可作为润滑剂的贮存场所,因而被认为是润滑环境中机械零部件的重要保护涂层。 CrN涂层在汽车发动机零件上作为保护层来降低摩擦因数(COF)和提高耐磨性,极大地提高了燃油经济性和发动机高效性[1-2]。鉴于CrN涂层在汽车发动机系统中具有良好的应用背景,但本身耐高温性能较差[3],因此有必要进一步提高CrN涂层性能。近年来,在CrN涂层的基础上掺杂元素制备三元或四元的CrN基复合涂层受到了研究学者的广泛关注。研究发现,在CrN涂层中掺杂适量Al元素,可显著地提高CrN涂层的硬度、抗氧化性、热稳定性和摩擦学性能[4-5]。

  • 油溶性有机钼添加剂———二烷基二硫代氨基甲酸钼(MoDTC) 是一种性能优异的摩擦改进剂[6-7], 可有效降低滑动过程中材料的摩擦和磨损。然而, 添加剂在具有不同化学成分(质量分数)的材料上可能以不同的方式发挥作用,添加剂是否发挥功能与摩擦副材料的化学性质存在直接关系[8-9]。 YUE等[10-11]发现一定浓度的MoDTC能提高渗氮或渗硫处理后钢的摩擦学性能。但在添加MoDTC后的基础油润滑下DLC/钢体系中DLC膜的磨损反而增加了[12]。目前对CrAlN涂层的摩擦学性能的研究大多集中在干摩擦条件下[13-14],而对其与MoDTC添加剂相互作用的研究鲜有报道。基于此,本研究采用直流磁控溅射技术分别制备了CrN和CrAlN涂层,系统研究了MoDTC对两种涂层摩擦学性能的影响,并阐明了PVD涂层在PAO6+1wt%MoDTC油润滑下的减摩抗磨作用机制。研究结果对合理选择或设计新型添加剂,扩大对材料摩擦化学反应机理的认识具有重要的意义。

  • 1 试验准备

  • 1.1 CrN和CrAlN涂层的制备

  • 采用直流磁控溅射技术,在304不锈钢(用于机械和摩擦学性能测试)和单晶硅(用于观察微观结构)表面沉积CrN和CrAlN涂层[15]。沉积过程中,使用了Cr(99.9%靶)和Al(99.9%)靶,通过控制目标靶材的挡板从而可得到不同类型的涂层。将基体分别用石油醚、酒精和去离子水超声清洗15min,然后用N2 吹干并置于腔室内的旋转支架上,样品距离靶材150mm,支架以3r/min的速度旋转以确保涂层成分和厚度的均匀性。将腔室抽空至低于4mPa,在-800V的高脉冲偏压下对基体进行15min Ar + 刻蚀,以去除表面的氧化层等杂质。制备CrN涂层前,在基体表面先沉积10min Cr过渡层。而制备CrAlN涂层前,先后在基体表面分别沉积10min Cr和CrN过渡层以提高涂层的黏结强度。 CrN或CrAlN涂层的具体沉积参数如表1所示。

  • 表1 涂层的沉积参数

  • Table1 Deposition parameters of coatings

  • 1.2 CrN和CrAlN涂层的表征

  • 采用X射线衍射仪 ( XRD, Bruker D8Discover)对涂层进行物相分析,选用Cu靶( λ=0.154nm),测试参数为40kV和40mA,扫描速度为4 ( °)/min,步长为0.02°,扫描角度范围介于20°~80°。采用场发射扫描电子显微镜 ( SEM, MERLIN Compact, Carl Zeiss Microscopy GmbH)及其所配备的X射线能谱分析仪( EDS) 对试样表面进行元素成分分析。通过纳米压痕仪 (G200, MTS) 测试涂层的硬度和弹性模量,测试过程中将压痕深度控制在120nm。为保证数值的可靠性,需至少在试件的不同位置做6次压痕测试,最后取算术平均值。利用X射线光电子能谱仪(XPS, AXIS-ULTRA)分析磨损痕迹内部元素化学价态的变化,使用C1s结合能(284.8eV) 进行能量校准。

  • 1.3 摩擦磨损性能测试及表征

  • 利用摩擦磨损测试仪(UMT-3, CETR)考察在PAO6基础油和PAO6+1wt%MoDTC油润滑条件下CrN和CrAlN涂层的摩擦学性能。试验测试前,上试球需要分别用无水乙醇和石油醚超声清洗15min,用滴管取50 μL润滑剂滴落在上试球和下试件接触区域。试验在室温20±5℃下进行,载荷2N(最大接触应力825.0GPa), 平均滑动速度24mm/s, 行程6mm,滑动时长3 600s,总滑动距离86.4m。利用表面轮廓仪(SJ-200, Mitutoyo, Japan)测量涂层的磨痕截面,后根据式(1)计算出磨损率:

  • W=V/(S×L)
    (1)

  • 式中,V 为磨损体积,通过对磨痕多个位置的横截面积进行积分,然后乘以行程得到的。 S 为滑动距离 (mm),L 为垂直加载力(N)。所有摩擦试验均重复三次。

  • 采用SEM对涂层摩擦运动后的磨痕进行观察,并利用EDS对磨痕内部进行元素成分分析,表面分析前用蒸馏水仔细冲洗试样。借助XPS对接触区进行化学组成及价态分析,阐明甘油的润滑机理。

  • 所用PAO6基础油在20℃ 时的动力黏度为57.1mPa·s。通过式(2)计算试验条件下的 λ 值,以确定润滑系统处于何种润滑状态:

  • λ=hminσ=hminσ12+σ22
    (2)

  • 式中,h min 是润滑时的最小油膜厚度,σ 是摩擦副的复合表面粗糙度,σ1 和 σ2 分别是上试球和涂层的表面粗糙度。 CrN和CrAlN的 λ 计算值均小于1, 表明该试验是在边界润滑条件下进行的[16]。

  • 2 结果及讨论

  • 2.1 CrN和CrAlN涂层的微观结构及形貌

  • 图1 为CrN和CrAlN涂层的表面及截面的SEM图像,由图可看出,CrN和CrAlN涂层的表面较为光滑平整,试验测得表面粗糙度 Ra 分别为30nm和25nm,与不锈钢基体(Ra=40nm)相比均有所减小。两种涂层未出现明显的缺陷,与基体结合良好。 CrN和CrAlN涂层的厚度差异不大, 分别为1.61 μm和1.66 μm。 CrN涂层表现出典型的柱状晶特性,柱状晶间具有明显的边界。而CrAlN涂层的柱状晶特征明显减弱,涂层密度有所增加,结构较为致密。在涂层的表面进行了相应的EDS分析,以确定涂层的元素含量,结果示于表2中。

  • 图1 涂层的表面和截面形貌

  • Fig.1 Surface and cross-sectional morphology of the coatings

  • 表2 基底和涂层的化学成分

  • Table2 Chemical composition of substrate and coatings

  • CrN和CrAlN涂层的XRD图谱示展于图2中, 在CrN涂层的图谱中,观察到了面心立方结构的CrN(111)和CrN(200)相及三方结构的Cr2N(300) 相。 CrAlN涂层主要呈现CrN(111)和CrN(200)择优取向,同时由于AlN在CrN中具有很高的溶解度[17],使该涂层中含有大量的hcp-AlN相[18]。此外,相比于CrN涂层,CrAlN涂层(111) 和(200) 晶面衍射峰的强度明显增大,且向更高的衍射角度方向发生偏移。这是由大量离子半径更小的Al替换Cr离子引起晶格收缩,最终导致晶格参数降低所造成的[19]。利用Sherrer公式[20] 可估算涂层的晶粒尺寸:

  • 图2 涂层的XRD图谱

  • Fig.2 XRD patterns of the coating

  • D=Kλβcos⁡θ
    (3)

  • 式中,K 为常数,通常取 K=1,λ 为X射线的波长 (nm),β 为试样宽化(rad),θ 则是衍射角(°)。由式 (3) 估算出CrN和CrAlN涂层的晶粒尺寸分别为11.8nm和8.4nm(参见表2)。由此可知,通过Al元素掺杂可使CrN涂层的晶粒细化。

  • XPS是一种分析涂层表面化学性质的有效技术手段。 CrN和CrAlN涂层的XPS谱图示于图3,在N1s图谱(图3a) 中,位于399.2±0.4eV处的峰可归于CrNxOy,这是由沉积过程中涂层表面被氧化所致[21]。在CrN涂层中,位于396.8±0.4eV处的峰可归于CrN,而在CrAlN涂层中,对应的峰则可归于AlN或CrN [22]。在CrAlN涂层的Al2p图谱(图3b)中, 位于74.7eV和78.2eV处的峰可分别归于CrN和Cr2O3,而在73.6eV处观察到的另一个峰则可归于AlN [22]。 XPS分析表明,CrN涂层的主要存在形式为CrN,而CrAlN涂层的主要存在形式为CrN和氧化产物CrNxOy,涂层中的Al元素主要以AlN的形式存在,该结果与上述的XRD分析结果相一致。

  • 图3 涂层表面N 1s和Al2p的XPS图谱

  • Fig.3 XPS Spectra of N 1s and Al2p obtained from the surfaces of the coating

  • 2.2 CrN和CrAlN涂层的力学性能

  • 如图4所示,在相同的压痕深度下,CrAlN涂层所需的加载力明显大于CrN涂层,前者的硬度和弹性模量均高于后者。如表3所示,CrAlN涂层的硬度和弹性模量分别为23.8GPa和335.6GPa,而CrN涂层的硬度和弹性模量则分别为12.4GPa和184.3GPa。此外,H 3/E 2 和 H/E 的数值可分别衡量涂层抵抗弹性和塑性变形能力的大小[23]。由表3可看出,CrAlN涂层的 H 3 /E 2 和 H/E 值均大于CrN涂层,表明该涂层具有更好的抵抗弹性和塑性变形的能力,在一定程度上反映出该涂层具有更好的耐磨性。

  • 图4 CrN和CrAlN涂层的加载-卸载曲线

  • Fig.4 Load-displacement curves for CrN and CrAlN coatings

  • 表3 基底和涂层的力学性能

  • Table3 Mechanical performance of substrate and coatings

  • 2.3 CrN和CrAlN涂层的摩擦学性能

  • 图5 给出了在PAO6基础油和PAO+MoDTC油润滑下钢球分别与基底和涂层对磨过程中的摩擦因数随时间变化曲线。不难看出,在不锈钢表面沉积CrN或CrAlN涂层可有效降低摩擦因数。在PAO6基础油润滑下不锈钢经过800s磨合后的COF稳定在0.12,该数值与在PAO6+MoDTC润滑时的COF相差不大,但磨合时间明显减少。对于CrN涂层, 在PAO6基础油润滑时磨合期比不锈钢明显缩短, COF值最终稳定在0.14, 略高于不锈钢, 但在PAO6+MoDTC润滑下的COF由滑动初期的0.10逐渐降至0.07。对于CrAlN涂层,在PAO6基础油润滑时的COF仅为0.11,而当在PAO6中添加MoDTC后COF显著降低,最终稳定在0.04,表现出优异的减摩特性。图6为在PAO6和PAO6+MoDTC油润滑下不锈钢及两种涂层的磨损率。由图可知,在PAO6润滑下不锈钢的磨损率可达到4.1 × 10-5 mm 3N-1m-1,而在PAO6+MoDTC油润滑下磨损率也达到2.4×10-5 mm 3N-1m-1 ,两种润滑条件下不锈钢的磨损率均较大。相反, 在PAO润滑下CrN和CrAlN涂层的磨损率仅分别为9.9×10-6 mm 3N-1m-1 和9.4×10-6 mm 3N-1m-1,比在同种润滑条件下的不锈钢磨损率降低了约76%。在PAO+MoDTC润滑时CrN涂层磨损率低至3.0 × 10-7 mm 3N-1m-1, CrAlN涂层的磨损率仅为1.0×10-8 mm 3N-1m-1,后者比前者降低了近一个数量级,而比在PAO6基础油润滑时的不锈钢的磨损率降低了三个数量级,表现更优异的耐磨特性。

  • 图5 摩擦因数随时间变化曲线

  • Fig.5 Evolution of coefficient of friction with sliding time

  • 图6 在PAO6和PAO6+1wt%MoDTC油润滑下不锈钢及涂层的磨损率

  • Fig.6 Wear rates of substrate and coatings lubricated by PAO6and PAO6+1wt%MoDTC

  • 摩擦运动后磨痕处的SEM形貌如图7所示。在PAO6油润滑下,不锈钢的磨痕内部布满了沿滑动方向的划痕和犁沟,接触区边缘发生了严重的塑性变形,磨痕宽度为309.6 μm,以磨粒磨损为主。在PAO6中添加1wt%MoDTC后,不锈钢磨痕宽度增至324.5 μm。而在PAO6基础油润滑下CrN和CrAlN涂层的磨痕宽度和内部犁沟数量均明显小于不锈钢。同时还发现,CrN涂层在磨痕处被完全破坏,而CrAlN涂层的磨痕内部出现部分脱落现象,但两者的受损程度均小于不锈钢。但当在PAO6中添加1wt%MoDTC后,CrN和CrAlN涂层的磨痕宽度明显减小,特别是CrAlN涂层,磨痕表面变得光滑平整,宽度仅为78.2 μm,只发生轻微磨损。

  • 图7 磨痕的SEM形貌

  • Fig.7 SEM image morphology for wear scar

  • 2.4 XPS分析及MoDTC作用机制

  • 为探究在PAO6+MoDTC油润滑下CrAlN涂层表现出优异润滑性能的机理,对其磨痕接触区域进行了XPS分析,结果如图8所示。从Mo3d的XPS谱峰可看出,在结合能232eV和229.7eV处存在两个峰值,分别对应于钼的氧化物(MoO3)和钼的硫氧化物(MoOxSy) [24-25]。而在CrN和CrAlN涂层磨痕处,除上述两个峰外,在229±0.2eV出现一个相对明显的峰,对应于钼的硫化物(MoS2)。与CrN涂层相比,在CrAlN涂层磨痕处的MoS2 峰值强度更高,表明该接触区域形成更多含量的MoS2。

  • 图8 磨痕内部Mo3d的XPS图谱

  • Fig.8 XPS spectra of Mo3d obtained inside the wear scar

  • 研究表明,在边界润滑条件下,MoDTC分子首先吸附在接触区表面,在滑动过程中发生化学降解, 生成一层含MoS2 的摩擦膜,从而极大地降低摩擦副的摩擦和磨损[25-26]。 MoDTC分子的降解反应可能经历两个步骤:首先,MoDTC降解生成MoOxSy, 随后进一步降解生成MoS2 和MoO3,其中MoO3 是由MoS2 氧化而生成的。显然,MoDTC的减摩特性与其降解程度有关。在边界润滑条件下,MoDTC的降解程度受诸如负载、温度、湿度、摩擦副材料等多种因素的影响,其中摩擦副材料表面化学特性对MoDTC降解反应进行的程度影响较大[27-28]。 XPS分析表明,在PAO6+1wt%MoDTC油润滑下摩擦运动过程中不锈钢表面上生成一层润滑膜,主要成分为MoOxSy 和MoO3,表现出较差的摩擦学性能。而CrN和CrAlN涂层表面因具有较高的活性,故在摩擦过程中更容易促进接触区的MoDTC发生摩擦化学反应,使其降解生成MoS2,故具有更好的润滑性能。特别是CrAlN涂层,因存在AlN相,可进一步促进MoDTC完全降解,使生成的润滑膜中含有更高含量的MoS2,因而表现出更好的摩擦学性能。换言之, 润滑膜中MoS2 的含量与MoDTC添加剂减摩和抗磨性存在直接关系,润滑膜中MoS2 含量越高,减摩和抗磨性能越好。

  • 3 结论

  • 利用磁控溅射技术制备了CrN和CrAlN涂层,对比了两种涂层的微观机构、力学性能, 考察了PAO6基础油中MoDTC添加剂对CrN和CrAlN涂层摩擦磨损性能的影响,主要结论如下所述:

  • (1) CrN涂层的主要存在形式为CrN,而CrAlN涂层中Al元素主要以AlN的形式存在。掺杂Al元素可使CrN涂层晶粒细化,结构更加致密,同时硬度和弹性模量等机械性能均得到提高。

  • (2) 与CrN涂层相比,CrAlN涂层在含1wt%MoDTC基础油润滑下表现出优异的摩擦学性能,摩擦系数降低了42%,磨损率下降了近一个数量级。

  • (3) XPS研究表明,MoDTC在CrN和CrAlN涂层表面接触区域发生摩擦化学反应,降解生成含MoS2 的润滑膜。特别是在CrAlN涂层表面中, MoDTC降解反应进行的程度更大,润滑膜中MoS2 的含量更高,因而表现出更优异的润滑特性。

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  • 基本信息

    中图分类号: TG174;TH117
    文献标识码: A
    DOI: 10.11933/j.issn.1007-9289.20210804002

    基金信息

    国家自然科学基金(51975304)、山东省自然科学基金(ZR2019MEE016)和 2018 年工业强基工程(TC180A3Y1)资助项目；
    Supported by National Natural Science Foundation of China ( 51975304 ), Natural Science Foundation of Shandong Province (ZR2019MEE016), and Strong Industrial Foundation Project in 2018(TC180A3Y1).；

    引用信息

    稿件历史

    收稿日期: 2021-08-04

  • 参考文献

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    • [2] 刘吉良,廖日东,罗军,等.20CrMo 上沉积CrN涂层的力学性能及 5W/40 润滑下的摩擦学性能[J].中国表面工程,2017,30(6):103-110.LIU Jiliang,LIAO Ridong,LUO Jun,et al.Mechanical properties of CrN coating on 20CrMo and its tribological properties under 5W/40 oil [J].China Surface Engineering,2017,30(6):103-110.(in Chinese)

    • [3] 王顺花,尚伦霖,张广安,等.DLC 和CrN薄膜在油润滑下的摩擦性能[J].宇航材料工艺,2014,44(6):20-25.WANG Shunhua,SHANG Lunlin,ZHANG Guangan,et al.Tribological properties of DLC and CrN films under engine oil [J].Aerospace Materials & Technology,2014,44(6):20-25.(in Chinese)

    • [4] LONG Y,ZENG J,YU D,et al.Microstructure of TiAlN and CrAlN coatings and cutting performance of coated silicon nitride inserts in cast iron turning[J].Ceramics International,2014,40(7):9889-9894.

    • [5] 吕艳红,吉利,刘流,等.调制周期对 CrAl/CrAlN 多层薄膜结构及耐腐蚀性能的影响[J].中国表面工程,2013,26(5):18-23.LÜ Yanhong,JI Li,LIU Liu,et al.Influence of modulation periodicities on structure and corrosion properties of CrAI/CrAIN multi-layer films[J].China Surface Engineering,2013,26(5):18-23.(in Chinese)

    • [6] 于强亮,蔡美荣,周峰,等.油溶性有机减摩抗磨添加剂的研究进展[J].表面技术,2020,49(9):1-18.YU Qiangliang,CAI Meirong,ZHOU Feng,et al.Research progress of oil-soluble organic anti-friction and anti-wear additives [J].Surface Technology,2020,49(9):1-18.(in Chinese)

    • [7] DU S,YUE W,WANG Y,et al.Synergistic effects between sulfurized-nanocrystallized 316L steel and MoDTC lubricating oil additive for improvement of tribological performances [J].Tribology International,2016,94,530-540.

    • [8] GARCIA C E,UEDA M,SPIKES H,et al.Temperature dependence of molybdenum dialkyl dithiocarbamate(MoDTC)tribofilms via time-resolved Raman spectroscopy [J].Scientific Reports,2021,11(1):3621.

    • [9] DE FEO M,MINFRAY C,BOUCHET MI D B,et al.Ageing impact on tribological properties of MoDTC-containing base oil [J].Tribology International,2015,92:126-135.

    • [10] YUE W,FU Z Q,WANG S,et al.Tribological synergistic effects between plasma nitrided 52100 steel and molybdenum dithiocarbamates additive in boundary lubrication regime [J].Tribology International,2014,74:72-78.

    • [11] YUE W,LIU C Y,FU Z Q,et al.Synergistic effects between sulfurized W-DLC coating and MoDTC lubricating additive for improvement of tribological performance [J].Tribology International,2013,62:117-123.

    • [12] VENGUDUSAMY B,GREEN J H,LAMB G D,et al.Behaviour of MoDTC in DLC/DLC and DLC/steel contacts[J].Tribology International,2012,54:68-76.

    • [13] DRNOVSEK A,DE FIGUEIREDO M R,VO H,et al.Correlating high temperature mechanical and tribological properties of CrAlN and CrAlSiN hard coatings[J].Surface and Coatings Technology,2019,372:361-368.

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