文章信息/Info

Title:

Research progress of hexagonal close-packed high-entropy alloys

作者:

鮑美林; 喬珺威

太原理工大學材料科學與工程學院高熵合金研究中心

Author(s):

Meilin Bao;  Junwei Qiao

Research Center for High-entropy Alloys, School of Materials Science and Engineering, Taiyuan University of Technology

關鍵詞:

高熵合金; 密排六方結構; 物相參數; 稀土元素; 貴金屬元素; 機械性能; 磁性能

Keywords:

High-entropy alloys;  Hexagonal close-packed structure;  Physical parameters;  Rare earth elements;  Precious metal elements;  Mechanical property;  Magnetic ability

DOI:

10.7502/j.issn.1674-3962.2018.04.03

文獻標志碼:

A

摘要:

高熵合金自問世以來，因其性能獨特很快就引起了廣大學者的興趣。對高熵合金的定義現在大家普遍認為的是由五種及五種以上的主要元素以等摩爾比或近似等摩爾比構成，且每種元素占總成分的5%-35%。對配置熵、混合焓、原子半徑差、價電子濃度等物相參數進行計算，并結合CALPHAD相圖模擬和第一性原理密度泛函理論（DFT）以及AIMD模擬，可用來初步預測高熵合金的相結構。目前，主要有面心立方（FCC）、體心立方（BCC）和密排六方結構（HCP）三大類固溶體高熵合金，其中HCP高熵合金鮮見，主要為稀土元素類和貴金屬元素類HCP高熵合金。近幾年研究發現FCC高熵合金通過特殊的處理方式（如高壓）也可轉變成HCP高熵合金。本論文對HCP高熵合金的結構、相形成規律以及性能進行了綜述。

Abstract:

Since the study of High-entropy alloys (HEAs), it possesses excellent properties, currently attracting increasing researcher interest. It is now generally accepted that the definition of high-entropy alloy is composed at least five principal elements with equimolar ratio or approximately equimolar ratio. Meanwhile, the composition of each element varies from 5 to 35 %. The configuration entropy, mixing enthalpy, atomic radius difference, valence electron concentration and other physical parameters were calculated, combining with CALPHAD phase diagram simulation and first-principles density functional theory (DFT) and AIMD simulation, to predict the phase structure of High-entropy alloys. At present, three types of high-entropy alloys are mainly composed of FCC, BCC and HCP. HCP high-entropy alloys are scarce and mainly consist of rare earth elements and precious metal elements HCP high entropy alloy.In recent years, it has been found that FCC high-entropy alloys can also be transformed into HCP high-entropy alloys through special treatment methods (such as high pressure). In this paper, the structure, phase formation and properties of HCP high-entropy alloys are reviewed.