非平衡磁控溅射La-Ti/WS2 自润滑薄膜的摩擦磨损行为

Friction and Wear Behavior of Self-lubricating La-Ti/WS2 Films by Unbalanced Magnetron Sputtering

摘要:

要满足航天器机械转动部件在恶劣工况下的工作，需研制高硬度、低摩擦系数的固体润滑薄膜。采用非平衡磁控溅射法分别制备了纯WS₂薄膜、Ti掺杂WS₂复合薄膜和La-Ti掺杂WS₂复合薄膜。分析了薄膜的微观形貌、成分、硬度和摩擦学性能。结果表明，与纯WS₂薄膜和Ti/WS₂复合薄膜相比，La-Ti/WS₂复合薄膜的微观结构更加致密。La-Ti/WS₂复合薄膜的硬度H和弹性模量E也显著提高。此外，La-Ti/WS₂复合薄膜的摩擦系数减小，并且H/E比值增大，La-Ti/WS₂复合薄膜的磨损率降低。结果表明，La的掺杂有助于在摩擦接触表面形成稳定的转移膜，提高La-Ti/WS₂复合薄膜的耐磨性和承载能力。

Abstract:

The solid lubrication films with high hardness and low friction coefficient should be developed to satisfy the severe working conditions of mechanical rotating parts of spacecraft. The pure WS₂ film, Ti doped WS₂ composite film (Ti/WS₂) and La-Ti doped WS₂ composite film (La-Ti/WS₂) were prepared by unbalanced magnetron sputtering. The micro morphology, composition, hardness and tribological performance of the films were examined. Results show that compared with pure WS₂ films and Ti/WS₂ composite films, the microstructure of La-Ti/WS₂ composite film becomes more compact. Meanwhile, the hardness and elastic modulus of La-Ti/WS₂ composite film also increase significantly. Furthermore, the friction coefficient of La-Ti/WS₂ composite film decreases, and the hardness/elastic modulus (H/E) ratio of La-Ti/WS₂ composite film increases, which suggests that the wear rate of La-Ti/WS₂ composite film is reduced. It is indicated that La doping contributes to the formation of stable transfer film on the friction contact surface, and thus improves the wear resistance and carrying capacity of La-Ti/WS₂ composite film.