跨环境连续超润滑碳膜的设计、制备及摩擦学性能研究

During the past two decades, carbon films have attracted an overwhelming interest because of their excellent properties. As well known, pure carbon films have intrinsic limitations in applications as protective coatings, such as sensitivity of friction performance. In order to overcome this disadvantage, introducing some other elements is a primary method. Si incorporation is conducive to suppress the sensitivity of friction coefficient to humility. Furthermore, Ti or Al and Si co-doped carbon films with super-low friction character in ambient air or vacuum have been prepared in our group. However, at present the study on carbon films with continuous superlubricity from ambient air to vacuum has not been realized. In this proposal, we aim to develop it using metal/nonmetal multielement co-doping and the multilayer or gradient composite technique by vapor deposition, which has the theoretical significance and application valuations. In more detail, we will systematically study (1) design and selection on the ingredient of the target materials and decision of the deposition technology; (2) effects of the species, content of the doping element and processing parameters on the composition, microstructures and mechanical and tribological properties of the carbon films, and optimization of the processing parameters; (3) regulation mechanism of the co-doping elements, influence laws of the synergistic action of the doping elements on the properties, and realization condition of the continuous superlubricity of the carbon films; (4) super-low friction and wear behavior laws of the carbon films in ambient air and vacuum; (5) continuous super lubrication and failed mechanism of the materials. We expect the following significant beneficial outcomes from this proposal: (1) deeper understanding of the continuous super lubrication theory that to enrich the theoretical foundation of tribology; (2) development of a new idea for continuous super lubricating materials and technique used in aerospace and mechanical electronic fields; (3) supply of theoretical basis and technical support for solving key lubrication problem in our country.

碳膜摩擦学的环境敏感性极大地限制了其应用。Si掺杂可降低其环境敏感性，但使其从大气到真空环境具有连续超润滑特性目前尚未实现。申请者预利用金属/非金属多元共掺杂技术来解决这一难题，具有重要的理论意义和应用价值。本项目在前期工作基础上拟采用气相沉积方法，通过设计靶材成分和优化工艺参数，将多元共掺杂技术与多层或梯度复合技术相结合，设计制备具有多环境连续超润滑性能的碳基薄膜材料。研究掺杂元素种类、含量及工艺参数对薄膜组成、结构和性能的影响规律，揭示掺杂元素的协同作用对薄膜微结构（sp3/sp2）的调控机制及其与性能的关系，提出连续超润滑碳基薄膜的实现条件。研究薄膜在典型环境中的摩擦学性能的影响因素，阐明润滑与失效机理。本项目的研究将深入认识碳基薄膜超润滑理论，丰富摩擦学基础知识，为发展适用于航空航天和机械电子等领域的新型碳膜材料与技术提供新思路，为解决我国关键润滑问题提供理论依据和技术支撑。

本课题围绕跨环境连续超润滑碳膜的设计、制备及摩擦学性能研究这一科学问题，采用真空等离子体共沉积技术，制备出了(Ti,Si)/a-C:H、(Al,Si)/a-C:H、(W,Al)/a-C:H等系列多元共掺杂碳膜，利用多元金属/非金属的协同作用，获得了兼具良好机械性能、摩擦性能等综合性能的 DLC 薄膜材料。所制备的(Ti,Si)/a-C:H共掺杂薄膜的摩擦系数最低，稳态摩擦系数为0.0095，达到0.01量级的超低摩擦状态。同时为了设计制备具有跨环境连续超润滑特性的薄膜材料，本项目采用了纳米复合、多层复合及梯度复合薄膜制备技术，并应用自主开发的低温等离子体后处理技术，制备了系列具有特殊纳米结构的跨环境连续超润滑碳基复合薄膜，并研究了薄膜在不同介质环境下的摩擦学性能。结果表明所制备的a-C/TiN、CrN/DLC、a-C/WS2基复合涂层均在大气或真空环境下实现了较低的摩擦系数，有望成为下一代适应于航空航天和机械电子等相关领域具有连续超润滑特性的新型碳基薄膜材料与技术的发展方向。同时，在多孔纳米结构复合润滑涂层的制备研究中，除了发现薄膜具有良好的润滑特性外，还制备出了具有良好透光性能和亲疏水性能的碳基润滑涂层。以上结果为解决我国相关工程的关键润滑问题提供理论依据和技术支撑。.本项目的研究成果，参与编著了《纳米润滑材料与技术》，在国内外学术期刊发表和接收论文12篇，申报国家发明专利4件，授权3件。