Effect of aluminum on the microstructure and properties of two refractory high-entropy alloys
Effect of aluminum on the microstructure and properties of two refractory high-entropy alloys
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DOI：
10.1016/j.actamat.2014.01.029
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发表时间：
2014-04-15
期刊：
影响因子：
9.4
通讯作者：
Woodward, C.
中科院分区：
文献类型：
--
作者：
Senkov, O. N.;Senkova, S. V.;Woodward, C.
报道了AlMo 0.5NbTa 0.5TiZr和Al 0.4Hf 0.6NbTaTiZr高熵合金的显微组织、相组成和力学性能。AlMo0.5NbTa0.5TiZr合金由两个体心立方（bcc）相组成，具有非常接近的晶格参数，a（1）= 326.8 pm和a（2）= 332.4 pm。一个相富含Mo、Nb和Ta，另一个相富含Al和Zr。这些相在等轴晶内形成纳米层状调制结构。该合金的密度为rho = 7.40 g cm（-3），维氏硬度H-v = 5.8 GPa。其屈服强度在298 K时为2000 MPa，在1273 K时为745 MPa. Al0.4Hf0.6NbTaTiZr具有单相bcc结构，晶格参数a= 336.7 pm。该合金的密度ρ = 9.05 g cm-3，维氏显微硬度H-v = 4.9 GPa，298 K和1273 K下的屈服强度分别为1841 MPa和298 MPa。将这些含Al合金的性能与母体CrMo0.5NbTa0.5TiZr和HfNbTaTiZr合金的性能进行了比较，并概述了Al添加剂对组织和性能的有益影响。对这些合金的凝固相图和平衡相图进行了热力学计算，并将计算结果与实验数据进行了比较。(C)2014 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
The microstructure, phase composition and mechanical properties of the AlMo0.5NbTa0.5TiZr and Al0.4Hf0.6NbTaTiZr high-entropy alloys are reported. The AlMo0.5NbTa0.5TiZr alloy consists of two body-centered cubic (bcc) phases with very close lattice parameters, a(1) = 326.8 pm and a(2) = 332.4 pm. One phase was enriched with Mo, Nb and Ta and another phase was enriched with Al and Zr. The phases formed nano-lamellae modulated structure inside equiaxed grains. The alloy had a density of rho = 7.40 g cm(-3) and Vickers hardness H-v = 5.8 GPa. Its yield strength was 2000 MPa at 298 K and 745 MPa at 1273 K. The Al0.4Hf0.6NbTaTiZr had a single-phase bcc structure, with the lattice parameter a= 336.7 pm. This alloy had a density rho = 9.05 g cm(-3), Vickers microhardness H-v = 4.9 GPa, and its yield strength at 298 K and 1273 K was 1841 MPa and 298 MPa, respectively. The properties of these Al-containing alloys were compared with the properties of the parent CrMo0.5NbTa0.5TiZr and HfNbTaTiZr alloys and the beneficial effects from the Al additions on the microstructure and properties were outlined. A thermodynamic calculation of the solidification and equilibrium phase diagrams was conducted for these alloys and the calculated results were compared with the experimental data. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.