金属/高熵合金纳米多层膜的制备、微观结构及力学性能研究进展

Research Progress on the Preparation,Microstructure and Mechanical Properties of Metal/High-Entropy Alloy Nanostructured Multilayers

通过表面防护涂层技术制备综合力学性能与摩擦性能优异的涂层材料,对降低构件因碰撞摩擦磨损所引起的损伤失效问题十分重要。相较于单层膜结构防护涂层,金属纳米多层膜涂层材料由于其微观组织结构的独特性与可控性,表现出优异的服役特性,且其综合性能可通过结合新组元或界面调控得到进一步提高,因此该类材料受到了广泛关注。新颖的成分设计理念使得高熵合金具有独特的四大效应,即高熵效应、晶格畸变效应、迟滞扩散效应和性能鸡尾酒效应,进而呈现出良好的综合性能。因此,在传统的双金属纳米多层膜结构材料中引入高熵合金组元,形成金属/高熵合金纳米多层膜,有望突破传统金属纳米多层膜的性能局限,极大地提高多层膜结构材料的力学性能。从功能基元序构的视角,围绕近几年金属/高熵合金纳米多层膜的相关研究,首先介绍了其制备方法和工艺原理,针对功能基元微观结构特征,从晶粒形貌、界面结构、组元成分等方面进行了阐释,在此基础上论述了其力学行为以及相应的内在机制,并提出了调控金属/高熵合金纳米多层膜力学性能的优化策略,最后对金属/高熵合金纳米多层膜的未来研究方向和面临的挑战进行展望。

The preparation of coating materials with excellent mechanical and friction properties through surface protective coating technology is important to reduce the damage failure of components caused by collision and friction wear.Compared with single-layer protective coatings,metallic nano-multilayer coatings have received extensive attention due to their unique and controllable microstructure,excellent service properties,and their comprehensive performance can be further improved by combining new components or interface modulation.High entropy alloys also have excellent properties due to their novel composition design and four major effects,including high mixture entropy,severe lattice distortion,sluggish diffusion,and cocktail effects.Therefore,the introduction of high entropy alloys into metallic nanostructured multilayers to form metal/high entropy alloy nanostructured multilayers may break through the performance shortcomings of traditional metallic nanostructured multilayers and greatly improve the mechanical properties.In this paper,the related researches on metal/high entropy alloy nanostructured multilayers in recent years are reviewed,from the perspective of functional units and ordered structure.This review firstly introduces the preparation methods and process principles.Secondly,this review elucidates the microstructure of functional units in terms of grain morphology,interfacial structure and component composition,and discusses the mechanical behavior and intrinsic mechanism,simultaneously proposing an optimization strategy for tuning the mechanical properties of metal/high entropy alloy nanostructured multilayers.Finally,the future research directions and challenges are prospected.