Abstract

In this study, we synthesized a new Al_16.6Cu_16.6Fe_16.6Mn_16.6Mg_16.6Ti_16.6 lightweight high entropy alloy (LWHEA) by high energy ball milling and spark plasma sintering (SPS). The effect of milling time (15, 30, 45, and 60 h) and SPS conditions (600 and 700 °C) on microstructure, hardness, and density of LWHEAs were studied. The results showed that milled LWHEA is base centered cubic (BCC) structured, consisting of dual BCC1/BCC2 matrix with dispersed minor Cu₂Mg precipitates and Ti. After SPS of milled samples, the BCC2 phase fraction was increased gradually. The distribution of Ti was uniform up to 45 h milled sample SPSed at 600 °C. However, porosity was built up beyond 45 h milling and higher SPS temperature (700 °C). The presence of finer secondary phases in the HEA matrix contributes to the dispersion hardening. The optimum microhardness and density of LWHEA AlCuFeMnMgTi were around 770 HV and 4.34 g cm^− 3 which is superior to other conventional alloys such as Al or Ti-based alloys.

Graphic Abstract

中文翻译：

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粉末冶金高强度密度比轻质AlCuFeMnMgTi高熵合金

摘要

在这项研究中，我们通过高能球磨和火花等离子体烧结（SPS）合成了一种新型的Al _16.6 Cu _16.6 Fe _16.6 Mn _16.6 Mg _16.6 Ti _16.6轻质高熵合金（LWHEA）。研究了铣削时间（15、30、45和60 h）和SPS条件（600和700°C）对LWHEAs的组织，硬度和密度的影响。结果表明，碾磨后的LWHEA为基心立方（BCC）结构，由双BCC1 / BCC2基体和分散的次要Cu _2组成镁沉淀和钛。研磨样品的SPS后，BCC2相分数逐渐增加。Ti的分布在600°C下经过45 h研磨的样品SPSed均一。但是，在铣削45 h和更高的SPS温度（700°C）之后，孔隙率逐渐增加。HEA基体中更细的第二相的存在有助于分散硬化。LWHEA AlCuFeMnMgTi的最佳显微硬度和密度约为770 HV和4.34 g cm ^-3，优于其他常规合金，如Al或Ti基合金。

图形摘要