摘要
材料表面性能直接影响着材料能否在特定环境中长期服役。表面涂层技术作为一种常用的表面改性方法,通过在基体表面涂覆一层或多层金属或非金属,提高基体耐磨、耐热、耐腐蚀、高温稳定等性能。难熔金属及其合金、金属间化合物、碳化物、氮化物等,因具有高温强度高、抗液态金属腐蚀性能好、可塑性加工等特点,已成为航空航天、国防军工等领域最具潜力的涂层材料。含难熔金属涂层的制备方法有热喷涂、激光熔覆、气相沉积等,且相关技术仍在不断优化和创新,以适应日益严苛的服役条件,如人们在传统热喷涂上进行改进,开发了超音速火焰喷涂和超音速等离子喷涂技术,结合激光熔覆和冷喷涂开发出激光辅助冷喷涂技术,还提出了利用接触固体渗碳方法获得难熔金属碳化物涂层。在研究较多的难熔金属涂层、合金涂层和碳化物涂层的基础上,学者通过成分及工艺优化不断改善涂层耐磨、耐高温等性能,还获得了具有独特性能的Ni-W、Ni-Mo、Ta纳米复合薄膜和Mo2C复合涂层及高硬度WN涂层;由于单一涂层的应用存在局限,开发具有不同功能的复合涂层已经成为研究热点,如具有润滑性能的难熔金属硫化物复合涂层、Mo2Si系复合涂层等;由于晶粒细化带来的优势,多种纳米级复合薄膜制备技术也有待开发推广。此外,在难熔金属涂层回收方面,关于WC涂层的回收提取技术研究较深入,而我国难熔金属回收再利用比例较低,从涂层中高效清洁回收难熔金属的关键技术有待研发。本文介绍了不同种类的含难熔金属涂层,包括金属基合金涂层、陶瓷涂层(主要包括碳化物涂层、氮化物涂层、硅化物涂层、硫化物涂层)、难熔高熵合金涂层等,综述了不同涂层的应用领域、制备方法及涂层中难熔金属的回收策略,指出了目前研究中面临的问题,展望了未来含难熔金属涂层的研究方向。
The surface properties of materials can directly affect whether the materials can be used in a specific environment for a long time.As a common surface modification method,surface coating technology can improve the properties of the substrate such as wear resistance,heat resistance,corrosion resistance and high temperature stability by coating one or more layers of metal or non-metal on the substrate.Refractory metals and their alloys,intermetallic compounds,carbides,nitrides,etc.,have become the most potential coating materials in aerospace,defense and military industries due to their excellent high-temperature strength,good resistance to liquid metal corrosion,plastic processing and ot-her characteristics.The preparation methods for refractory metal coatings include thermal spraying,laser cladding,vapor deposition,etc.,and related technologies are still being optimized and innovated to meet increasingly severe service conditions.For example,high velocity oxygen fuel spraying and supersonic plasma spraying technology have been developed on the basis of traditional thermal spraying.Researchers combined laser cladding with cold spraying technology,developed laser-assisted cold spraying technology,and also proposed a solid carburizing method to obtain refractory metal carbide coatings.On the basis of refractory metal,alloy and carbide coatings,researchers have continuously improved the wear resis-tance and high temperature resistance of the coatings through composition and process optimization.Ni-W,Ni-Mo,Ta nanocomposite film and Mo 2C composite coating with unique properties and high hardness WN coating are also obtained.Due to the limitations of single coating application,the development of composite coatings with different functions have become a research hotspot,such as refractory metal sulfide composite coatings with lubricating properties,Mo 2Si composite coatings,etc.According to the advantages brought by grain refinement,a variety of preparation technology for composite nanoscale film has yet to be developed.In addition,in the recovery of refractory metal coatings,the research on the recovery and extraction technology of WC coatings is more in-depth,but the proportion of refractory metal recycling in China is relatively low.The key technology for efficient and clean recovery of refractory metals from coatings needs to be developed.This article describes different types of refractory metal-containing coatings,including metal-based alloy coatings,ceramic coatings(mainly including carbide coatings,nitride coatings,silicide coatings,sulfide coatings),and refractory high entropy alloy coatings.The application fields of different coatings,preparation methods and recovery strategies of refractory metals are reviewed.The problems faced in the current research are pointed out,and the research direction of refractory metal coatings in the future is prospected.
作者
韩雪莹
刘新利
吴壮志
段柏华
王德志
HAN Xueying;LIU Xinli;WU Zhuangzhi;DUAN Bohua;WANG Dezhi(Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education,School of Materials Science and Engineering,Central South University,Changsha 410083,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第13期13146-13154,共9页
Materials Reports
基金
国家重点研发计划资助(2018YFC1901700)。
关键词
难熔金属
涂层
制备
回收
refractory metal
coating
preparation
recycling
