基于MAX相自润滑TiSi(CN)涂层多尺度耦合设计及其海水环境中磨蚀行为研究

In order to improve poor resistance wear of titanium moving parts of power transmission system from ships, deep diving mechine and ocean exploration in seawater environment with oil free lubrication, the multiscale coupled TiSi(CN) coatings with tribocorrosion resistance and self lubrication have been designed and prepared based on the contact stress simulation calculation and cooperative multiscale structure from the selflubricating layered structure of MAX phase, nanoscale amorphous and nanocrystalline with high strength and exellent toughness, micrometer scale multilayer and surface/interface optimization. Study on the effect of the surface nitride layer on load capacity and tribocorrosion properties of TiSi(CN) coatings. To investigate the effect michanism of MAX phase structure on antifriction properties in seawater. By measuring the dynamic wear and electrochemical corrosion parameters in situ, it is revealed the mechanism of formation and structure tunning of tribochemical reaction film related with environment and the influence of corrosion factor on crack initiation and growth induced by Hertz stress. It is studied that the structure evolution, tribocorrosion dynamic characteristic and mechanism of the interaction of wear and corrosion of the coatings with different structure at coupling mechanical – chemical/electrochemical fields in seawater. The intrinsical relation is revealed between coating structure and tribocorrosion properties in seawater. The results will expand the tribocorrosion theory on PVD coatings in seawater and suppot enhance manufacturing capability of ships and marine engineering equipment in hash marine environment.

本项目针对海水环境无油润滑舰艇、深潜器和海洋勘探等动力传动系统钛合金关键运动部件耐磨性差的瓶颈问题，基于自润滑MAX相层状结构、纳米尺度高强韧非晶纳米晶结构、微米尺度多层及表界面优化，利用接触力学模拟计算调控跨尺度结构协同效应，实现耐磨蚀自润滑TiSi(CN)涂层多尺度耦合设计和可控制备。研究钛表面氮化层对离子镀TiSi(CN)涂层承载及摩擦学性能影响的机械力学本质，探讨海水环境MAX相结构的减摩机理。采用动态摩擦与电化学腐蚀参数原位测量，研究环境响应摩擦化学反应膜的形成机制与结构调控，揭示腐蚀因素对赫兹应力诱发微裂纹萌生和扩展的影响机理。研究力学场和化学/电化学场耦合作用下涂层微结构演变和磨蚀动力学规律，揭示磨损与腐蚀交互作用规律和机制，阐明涂层组份结构与海水环境磨蚀性能之间的本构关系。拓展海洋环境PVD涂层腐蚀与摩擦学理论，为提升严酷海洋环境航行体和海工装备制造能力提供支撑。

本项目针对海水环境无油润滑舰艇、深潜器和海洋勘探等动力传动系统钛合金关键运动部件耐磨性差的瓶颈问题，基于自润滑MAX相层状结构、纳米尺度高强韧非晶纳米晶结构、微米尺度多层及表界面优化，调控跨尺度结构协同效应，实现耐磨蚀自润滑TiSi(CN)涂层多尺度耦合设计和可控制备。研究钛表面氮化层对离子镀TiSi(CN)涂层承载及摩擦学性能影响的机械力学本质，探讨海水环境TiSiCN涂层结构的减摩机理。研究力学场和化学/电化学场耦合作用下涂层磨蚀动力学规律，揭示磨损与腐蚀交互作用规律和机制。利用Solartron电化学工作站与MFT5000销盘式摩擦实验机相结合，通过自主开发设计的工装结构将两台设备组合，搭建了磨损与腐蚀协同作用材料损伤评价系统，建立了摩擦与腐蚀原位数据采集与解析方法，量化了磨损与腐蚀交互作用。基于高通量计算磨蚀数据处理平台软件的编写和应用，极大地节省了磨蚀计算过程所耗费的时间和效率，使得磨蚀交互作用的量化变得简单、高效和准确。. TiSiCN涂层中存在TiN/TiC/Ti(C,N)纳米晶-Si3N4/SiC非晶-Ti3SiC2 MAX相的耦合结构，利用非晶包覆纳米晶实现涂层的高强韧，利用纳米晶易钝化及与非晶的结构弛豫实现高耐蚀性能，利用TiC和MAX相固体润滑实现海水无油润滑。TiSiCN/氮化耦合涂层的最大纳米硬度为33GPa。TiSiCN涂层与离子氮化层复合后的结合力测试结果，其结合强度大于80N。TiSiCN/氮化耦合涂层的的摩擦系数低至0.23，磨损率比TC4基体降低了91.5％。对于TiSiCN涂层和TiSiCN/氮化耦合涂层，磨蚀过程中腐蚀电流分别是没有滑动的5.48倍和5.58倍，而腐蚀电位保持稳定并略有提高。TiSiCN/氮化耦合涂层磨损与腐蚀协同作用导致材料损耗占总体积损失的31%. 涂层损耗主要以磨损损耗为主，腐蚀增量因子占很大比例，磨损对腐蚀的影响更为显着。TiSiCN涂层与阴极保护同时用于材料防护会导致涂层的剥落发生，协同防护效果不理想。研究成果拓展了海洋环境PVD涂层腐蚀与摩擦学理论，为提升严酷海洋环境航行体和海工装备制造能力提供支撑。