项目面向生物医学工程等领域对高性能人工关节的迫切需求，针对高熵合金涂层人工关节的功能梯度、界面减阻、耐磨与抗疲劳性能的耦合仿生构建等科学问题开展研究。创新思路在于通过微纳米刻划测试新技术研究合金微区的微观磨损行为，采用多轴应力疲劳测试新技术揭示合金-髓腔界面的损伤机理。结合水凝胶润滑环境的构筑，借助断层扫描分析等对微缺陷演化行为的实时监测，开展接近服役条件下高熵合金涂层性能弱化机理的原位测试。基于获取的失效机理，分析微缺陷形核与扩展的阻滞效应，通过生物模本的优选，将多孔梯度材料“增韧”、非光滑形态“减阻”、非均质结构“抗疲劳”与异质材料“耐磨”进行功能耦联，突破“磨损松动、疲劳失效、性能弱化”等关键难题。项目着重阐明基于复杂应力的原位力学测试新技术，揭示服役条件下界面磨损与疲劳失效机理，并据此研究高熵合金涂层人工关节形态、结构与材料三元耦合仿生构建机制，为新型人工关节的研制提供理论基础。

Orienting to the urgent need of high-performance artificial joints in fields of biomedical engineering, etc., this project aims at a series of key scientific problems, such as functional gradient of high entropy alloy coating artificial joint and coupling bionic construction of interfacial drag reduction, wear resistance and anti-fatigue property. The innovative ideas involve studying the microscopic abrasive wear behavior of micro region of the alloy by using novel scratching testing technique at micro/nano scale, meanwhile, the fatigue damage mechanism of the “alloy-marrow cavity” interface would be also revealed through novel multi-axial stresses fatigue testing technique. Combined with the construction of hydrogel lubrication environment, the real-time monitoring of the evolution behavior of micro defects would be carried out by means of the tomography analysis technique, and the in-situ testing of the weakening mechanism of the properties of high entropy alloy coating joint material under approximate service condition would be focused. Based on the obtained failure mechanisms, the retardation effect of nucleation and propagation of micro defects would be further analyzed, via the optimal selection of biological templates, this project would functionally couple the “toughening effects” of porous gradient material, “resistance reduction effects” of the non-smooth morphologies, “crack arrest and anti-fatigue effects” of the heterogeneous structure and “wear-resisting effects” of heterogeneous materials together. It would also break through “wear and looseness, fatigue failure and weakening of performance” and other critical problems. In summary, this project focuses on elaborating the novel in-situ mechanical testing technique based on complicated stresses, revealing the interfacial wear and fatigue failure mechanisms under service condition and researching on the coupling bionic construction mechanisms of surface morphologies, structures and materials of high entropy alloy coating artificial joint, which would provide theoretical principle and contribute to the development of novel artificial joints.