PDF《偏压及测试环境对新型》

第33 卷第2期摩擦学学报Vol

33 No

2 2013 年3月Tribology Mar,2013 偏压及测试环境对新型MoS2 - Ti 复合膜摩擦学性能的影响秦晓鹏,柯培玲,汪爱英(中国科学院宁波材料技术与工程研究所宁波市海洋防护材料与工程技术重点实验室,浙江宁波315201) 摘要:采 用新型高功率脉冲复合磁控溅射技术制备MoS2 - Ti 复合膜,并研究基体偏压和测试环境对复合膜摩擦学性能的影响.

结果表明:制备的MoS2 - Ti 复合膜表面呈现颗粒状结构,Ti 在薄膜表层与O反应形成氧化物有效抑制MoS2 的氧化.随着基体负偏压从0V增大到-400 V, 复合膜的S/ Mo 原子比逐渐减小.在-300 V 偏压下,颗粒堆积最为紧密,薄膜硬度和弹性模量达到最大值,分别为9.

7 和137.

1 GPa,并具有最低的平均摩擦系数值(0 04) 和磨损率[(10 -

7 mm3 / ( N・ m) ] . 多种测试环境下的摩擦研究显示:在室温大气环境下复合膜的摩擦学性能与其结构的致密性紧密相关,而在N2 以及不同湿度环境下薄膜表现出的优异摩擦学性能则归因于在摩擦过程中有效形成的转移膜贡献.关键词:高 功率脉冲复合磁控溅射;

MoS2 - Ti 复合膜;

基体偏压;

摩擦学性能中图分类号:TH117.

3 文献标志码:A文章编号:1004 - 0595( 2013)

02 -

0162 -

07 Effect of Bias and Test Environments on Tribological Behavior of MoS2 - Ti Composite Coatings QIN Xiao - peng,KE Pei - ling ,WANG Ai - ying ( Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Material Technology &

Engineering,Chinese Academy of Sciences, Ningbo 315201, China) Abstract:The MoS2 - Ti composite coatings were deposited by a new hybrid high power impulse magnetron sputtering. The effect of the substrate bias and the multiple test environments on the tribological performance of the coatings was discussed. The results show that the composite coatings presented the granular surface morphology. The presence of titanium oxides from reaction of Ti with oxygen on the surface inhibited the oxidation of MoS2 . The atomic ratio of S to Mo decreased with the increase of the substrate negative bias from

0 V to -

400 V. The hardness and elastic modulus reached the maximum value at the substrate bias of -

300 V,due to the much denser microstructure with the smooth surface. Meanwhile,the composite coatings exhibited the lowest average friction coefficient ( 0. 04)as well as the wear rate [

10 -

7 mm3 / ( N・ m) ] . The tribological behaviors under multiple test environments indicate that the microstructure densification of composite coatings played a key role in the lubrication performance in ambient environment,while the excellent tribological property in N2 and various humidity conditions was greatly attributed to the effective formation of transfer film during friction tests. Key words:hybrid high power impulse magnetron sputtering,MoS2 - Ti composite coatings,substrate bias,tribology Received

13 August 2012, revised

21 November 2012, accepted

10 December 2012, available online

28 March 2013. Corresponding author. E - mail:kepl@ nimte. ac. cn,aywang@ nimte. ac. cn, Tel:+

86 -

574 - 86685036. The project was supported by the State Key Project of Fundamental Research of China ( 2013CB632302) ,National Natural Science Foundation of China ( 51005226)and Ningbo Municipal Government ( 2011B1016) . 国家重大基础研究计划(2013CB632300) 、 国家自然科学基金(51005226)和宁波重大攻关项目(2011B1016) 资助.磁控溅射MoS2 薄膜作为一种性能优良的固体润滑材料,由于其承载能力高、摩擦系数低等优点广泛用于空间及真空运动机构和部件等方面[1-2]. 但溅射MoS2 薄膜结构疏松、硬度低,在潮湿大气环境中容易被水蒸气、氧侵蚀导致润滑失效[3], 因而限制了其在大气环境中的应用.研究学者[4-8]通过金属共沉积来改善MoS2 大气环境下的摩擦磨损性能.Teer 等[6]研究发现,掺杂金属Ti 能提高MoS2 的抗氧化性和承载能力,使得薄膜的机械特性和摩擦学性能得到很大程度的改善.然而传统的溅射金属大多数以原子状态存在,金属离化率低(约 1% ) , 导致膜基结合力较差,薄膜的致密性及耐湿性不强,在多变大气及不同摩擦环境下致使润滑失效.不同于传统的磁控溅射方法,高功率脉冲磁控溅射(High Power Impulse Magnetron Sputtering, HIPIMS)技术利用较高的脉冲峰值功率和较低的脉冲占空比能够形成高密度等离子体,特别是对于金属靶材能获得高溅射速率和高离化率(约50% ) [