摘要
高熵合金涂层由于具有优于块体高熵合金和传统金属涂层的综合性能,在航空航天、核反应堆等极端服役环境下表现出了巨大的应用潜力。涂层低维形态产生的尺寸效应与高熵合金独特的多主元特征效应相耦合,使高熵合金涂层具有成分均匀、组织致密、结构稳定、性能优异等特点。概述了近年来高熵合金涂层的主要制备技术,简述了不同制备方法的原理、优势及工艺参数对涂层组织性能的影响。探讨了高熵合金中主要组元元素的作用、相结构的调控准则、多相转变行为等微观组织结构的特征与影响机制。论述了高熵合金涂层的服役性能特点,包括力学性能、抗氧化、耐腐蚀、抗辐照及耐磨损性能,并分析了成分/工艺-组织-性能的关联及相关作用机理。最后,总结了目前研究工作中存在的关键科学难题与挑战,对高熵合金涂层的研究方向与应用前景进行了展望。
Due to the excellent comprehensive properties superior to their bulk siblings and traditional metallic coatings,high-entropy alloy(HEA)coatings have exhibited great application potentials in extreme service environments such as in aerospace and nuclear reactors.The coupling of low-dimensional morphology induced size effect and unique HEA multi-principal effect endows the HEA coatings with homogeneous composition,dense and stable microstructure,and exceptional performances.In this paper,the main preparation technologies of HEA coatings in recent years were firstly introduced,such as the sputtering deposition,laser surface modification,electrochemical deposition and spraying technology,briefly describing the principles and advantages of different preparing processes,and the influence of process parameters on the microstructure and properties.Summary on the development status of HEA coating preparation technologies is beneficial to the design and optimization of process under a particular condition.Secondly,the effect of main constituent elements in HEAs,manipulating criteria of phase structure and phase transformation behavior were discussed.The constituent elements essentially make a crucial effect on the microstructure and service performance of HEA coatings.Especially,the thermodynamic effect between elements can tune the phase structure of HEA coatings,which also could be effectively predicted based on the related thermodynamic parameters.In addition,the phase transformation can take place in HEA coatings under the effect of preparation process,heat treatment,plastic deformation and irradiation,further changing their microstructures.Moreover,the service performances of HEA coatings,including mechanical properties,oxidation resistance,corrosion resistance,irradiation tolerance,and abrasion resistance,were elaborated,as well as analyzing the correlation of composition/preparation technology-microstructure-property and related mechanisms.Based on the theory of solid solution strengthening,grain boundary strengthening,dislocations strengthening,precipitation strengthening,phase-transformation strengthening,chemical short-range ordering and local chemical fluctuation strengthening,the HEA coatings exhibit outstanding mechanical properties.The unique microstructure of HEA coatings,such as high phase stability and chemical disordering,determines the significant oxidation resistance because the diffusion of oxygen and chemical reaction with constituent elements are effectively limited.The single-phase solid solution structure is not only in favor of oxidation resistance,but also can inhibit the generation of micro-batteries between heterogeneous phases and relieve the corrosion from chemical liquid.The sluggish diffusion effect of HEA coatings and the in-situ formation of passive or oxidation film can also effectively impede the penetration of harmful elements,improving the corrosion resistance.As for the irradiation resistance,the highly atomic solubility and complicated degree result in the difficult migration and aggregation of irradiated defects,dramatically enhancing the irradiation damage tolerance of HEA coatings.Finally,the key scientific problems and challenges in current research work of HEA coatings were summarized,concomitantly prospecting the development direction and application foreground.At present,great progress has been made in the study of HEA coatings,while there are still many scientific problems to be solved,such as the complexity of composition design,classical strength-plasticity tradeoff at room temperature,and performance optimization in harsh environment.The application of computational simulation,high throughput experiment and first-principles calculation in the research of HEA coatings will also become a fashionable development direction.
作者
李星
王亚强
张金钰
吴凯
刘刚
孙军
LI Xing;WANG Ya-qiang;ZHANG Jin-yu;WU Kai;LIU Gang;SUN Jun(State Key Laboratory for Mechanical Behavior of Materials,Xi'an Jiaotong University,Xi'an 710049,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2023年第1期1-20,46,共21页
Surface Technology
基金
国家自然科学基金项目(U2067219、U20B2027、52001247、92163201)
博士后创新人才支持计划项目(BX20190266)。
关键词
高熵合金涂层
制备技术
主元元素
微观结构
服役性能
high entropy alloy coating
preparation technology
principal element
microstructures
service properties
