Bioinspired Wear-Resistant and Ultradurable Functional Gradient Coatings
Bioinspired Wear-Resistant and Ultradurable Functional Gradient Coatings
复制标题
仿生耐磨超耐用功能梯度涂层
DOI：
10.1002/smll.201802717
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发表时间：
2018
期刊：
影响因子：
13.3
通讯作者：
Chiang Martin Y. M.
中科院分区：
文献类型：
--
作者：
Wang Zhengzhi;Wang Kun;Huang Houbing;Cui Xiao;Shi Xiaoming;Ma Xingqiao;Li Bei;Zhang Zuoqi;Tang Xuhai;Chiang Martin Y. M.
对于机械保护涂层，涂层材料通常需要足够的刚度和强度来抵抗外力，同时与下面的基底匹配机械性能以保持结构完整性。这些要求产生了限制涂层获得同时的表面性质（例如，高耐磨性）和涂层/基材界面耐久性。在这里，这种冲突是规避开发一种新的制造技术的功能梯度涂层（FGC）的材料组成和机械性能逐渐变化的涂层厚度。FGC通过磁致动过程控制聚合物基质内磁响应纳米增强物的空间分布来实现。通过将具有混合尺寸的增强物集中在表面区域并朝向涂层/基材界面连续减小，FGC被证明同时表现出高表面硬度、刚度和耐磨性，以及优异的界面耐久性，其性能超过均匀对应物一个数量级。FGC的概念代表了一种机械优化策略，根据许多承重生物材料的设计原则，以最少的使用和特定部位的增强分布实现最大性能。所提出的梯度纳米复合材料的制造技术可以扩展到开发具有所需机械性能的各种仿生非均质材料。
For mechanically protective coatings, the coating material usually requires sufficient stiffness and strength to resist external forces and meanwhile matched mechanical properties with the underneath substrate to maintain the structural integrity. These requirements generate a conflict that limits the coatings from achieving simultaneous surface properties (e.g., high wear‐resistance) and coating/substrate interfacial durability. Herein this conflict is circumvented by developing a new manufacturing technique for functional gradient coatings (FGCs) with the material composition and mechanical properties gradually varying crossing the coating thickness. The FGC is realized by controlling the spatial distribution of magnetic‐responsive nanoreinforcements inside a polymer matrix through a magnetic actuation process. By concentrating the reinforcements with hybrid sizes at the surface region and continuously diminishing toward the coating/substrate interface, the FGC is demonstrated to exhibit simultaneously high surface hardness, stiffness, and wear‐resistance, as well as superb interfacial durability that outperforms the homogeneous counterparts over an order of magnitude. The concept of FGC represents a mechanically optimized strategy in achieving maximal performances with minimal use and site‐specific distribution of the reinforcements, in accordance with the design principles of many load‐bearing biological materials. The presented manufacturing technique for gradient nanocomposites can be extended to develop various bioinspired heterogeneous materials with desired mechanical performances.