(中南大學(xué) 粉末冶金國家重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 高熵合金是一類由4、5種或者更多金屬元素，以近等原子比例構(gòu)成的新型金屬材料，也稱為復(fù)雜組元合金。由于其主要組元的非單一性，該類合金具有比傳統(tǒng)合金特殊的性能，例如高的強(qiáng)度和韌性、優(yōu)異的耐腐蝕性能和抗輻照性能等，但在制備方面，材料的組織均勻性以及缺陷控制也存在較大難度。粉末冶金與鑄錠冶金相比，在復(fù)雜成分合金的元素分布均勻性、組織細(xì)小程度以及近型成形等方面，具有明顯優(yōu)勢。本文首先介紹了高熵合金的基本特性，綜述了高熵合金的粉末冶金制備工藝，包括粉末制備、致密化工藝、近型成形技術(shù)等，隨后闡述了材料在組織和性能研究方面的基礎(chǔ)科學(xué)問題，最后對粉末冶金高熵合金及其復(fù)合材料的成分設(shè)計(jì)、性能優(yōu)化和工程應(yīng)用提出了建議和展望。
關(guān)鍵字: 高熵合金；粉末冶金；顯微組織；力學(xué)性能
（State Key Lab of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:High entropy alloys (HEA) are a novel kind of materials based on four or five (or more) metallic elements with near equal atomic ratio, which are also called compositional complex alloys (CCAs). High entropy alloys have novel properties compared with conventional alloys, such as high strength and toughness, excellent corrosion resistance and radiation resistance, due to the multi-principal element compositions. However, the homogeneity of microstructures and the control of crystal defects are difficult for high entropy alloy ingots. Compared with casting, powder metallurgy (PM) is a much better way to prepare HEAs with homogeneous compositions and fine microstructures. In this paper, the basic characteristics of HEAs were introduced firstly, and then, the PM methods, such as fabrication of powders, densification technologies and near-net shaping methods, for HEAs were summarized. Subsequently, the relationship of microstructures and properties of PM HEAs were discussed. Finally, some suggestions and prospects on compositional design, optimization of properties and engineering applications for PM HEAs were provided.
Key words: high entropy alloy; powder metallurgy; microstructure; mechanical property
