基于失效机制原位测试的高熵合金人工关节耦合仿生构建

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.

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。

“基于失效机制原位测试的高熵合金人工关节耦合仿生构建”（51875241）项目自2019年1月获批以来，围绕人工关节材料的失效机理原位测试与多元耦合仿生设计制备，对典型生物骨关节材料进行了微观力学性能原位测试研究，研究了皮质骨在微观尺度的力学行为，提出了皮质骨表面断裂路径的预测方法。基于对关节软骨表面力学性能分布以及关节软骨材料力学特性的研究，分析了影响关节软骨力学性能的因素和机理，揭示了关节软骨的强化与增韧机制。基于原位测试获取的关节材料微观失效机理，提出了人工关节多元耦合仿生设计思路，制备了具有多孔结构的仿生人工关节基体和基于高熵合金的关节涂层。开展了多元耦合仿生人工关节材料的压痕性能与等效耐磨性能测试，验证了仿生人工关节高熵合金涂层的抑菌性能，研究了高熵合金涂层材料的微观力学行为及其尺寸效应。设计并制备了具有减阻、抗粘附、自清洁功能的仿生人工关节表面微结构，揭示了仿生人工关节表面微结构的润湿性转变机理，研究了仿生人工关节表面的疏水性尺寸效应和液滴动态润湿行为。研制了新型人工关节材料磨损机理原位刻划仪器，仪器通过了机械工业试验机产品质量监督检验中心的质量检测，在中机试验装备股份有限公司等单位得到示范应用。项目执行期内，作为第一作者或通讯作者，在Nano Lett.、NPG Asia Mater.、Mater. Today Phys.、Research、J. Mater. Sci. Technol. IEEE Trans. Ind. Electron.、等期刊上上发表SCI收录论文41篇，其中2篇论文为ESI高被引论文，1篇论文被Nanoscale选为封面论文，6篇论文影响因子>10。授权第一发明人国家发明专利6件。项目负责人入选教育部青年长江学者，获第十六届吉林省青年科技奖、首届中国科技青年论坛一等奖、ICFDM2022优秀论文奖，入选《麻省理工科技评论》“35岁以下科技创新35人”2021年中国区榜单。