粉末冶金在高熵材料中的应用

Applications of powder metallurgy technology in high-entropy materials

  • 摘要: 高熵材料是近年来出现的一种新型材料,具有高强度、高硬度、良好耐腐蚀和优异的高温组织稳定性等性能,在航空航天、高温以及先进核能等领域展现了广阔的应用前景,引起国际材料领域的广泛关注,相关研究也取得了很大进展。粉末冶金作为一种高性能金属基和陶瓷复合材料的先进制备技术,可以获得纳米晶和过饱和固溶体等亚稳材料,同时也可用于传统熔炼法较难制备的具有特殊结构和性能的材料,近些年来,粉末冶金技术在高熵材料制备中得到广泛应用。本文从高熵材料的应用理论出发,针对目前高熵材料粉体制备方法、块体成型以及粉末冶金制备的典型高熵材料三个方面予以综述,着重阐述了高熵材料的力学性能和其变形行为特点,同时展望了高熵材料的未来发展趋势。

     

    Abstract: High-entropy materials (HEMs) designed with a new material design philosophy have recently emerged as a new type of advanced materials. In contrast to traditional alloys where one or two elements dominate the structural composition, HEMs comprise multiprincipal metallic or metalloid elements, generally ≥5 and in equiatomic or near-equiatomic ratios, thereby possessing high mixing entropy and generally forming a single-phase solid solution structure during solidification process. Because of their unique atomic structures, HEMs exhibit excellent properties such as high strength, hardness, corrosion resistance and structural stability at elevated temperatures. Hence, HEMs have great potential to be utilized in various high-tech areas, such as aerospace, high-temperature and nuclear energy fields, etc. HEMs have sparked great interests in the fields of materials and substantial progress has been made over the years. Powder metallurgy (PM) is an advanced technology that is often used to fabricate high-performance metal-based and ceramic composite materials possessing a metastable structure, such as nanocrystalline or supersaturated solid solution phases. In particular, it can also be applied to synthesize advanced materials with unique structures and properties that are difficult to achieve using conventional casting methods. Recently, PM has been extensively applied in studying HEMs, thereby considerably expanding their application range. In this review paper, we first introduce the concept and theories related to HEMs and briefly summarize research activities and progresses made with regards to the applications of PM in HEMs, including synthesis methods of powders, formation of bulk HEMs, and typical HEMs (i.e., nanocrystalline high-entropy alloys (HEAs), refractory HEAs, lightweight HEAs, dispersion strengthened HEAs, and high-entropy ceramics) fabricated using PM. In particular, we place emphasis on the mechanical properties and deformation behaviors of HEMs, specifically, the strengthening mechanisms in some typical HEAs fabricated by PM. Finally, the future prospects of HEMs are also briefly outlined.

     

/

返回文章
返回