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Microstructure and Mechanical Properties of VTaTiMoAlx Refractory High Entropy Alloys

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Materials Science Forum
Authors:
Dong Xu Qiao
Dong Xu Qiao
Dong Xu Qiao
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Hui Jiang at Shandong University of Science and Technology Location Qingdao, China
Hui Jiang
  • Shandong University of Science and Technology Location Qingdao, China
Xiao Xue Chang
Xiao Xue Chang
Xiao Xue Chang
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Yi Ping Lu
Yi Ping Lu
Yi Ping Lu
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Abstract and Figures

A series of refractory high-entropy alloys VTaTiMoAlx with x=0,0.2,0.6,1.0 were designed and produced by vacuum arc melting. The effect of added Al elements on the microstructure and mechanical properties of refractory high-entropy alloys were investigated. The X-ray diffraction results showed that all the high-entropy alloys consist of simple BCC solid solution. SEM indicated that the microstructure of VTaTiMoAlx changes from equiaxial dendritic-like structure to typical dendrite structure with the addition of Al element. The composition of different regions in the alloys are obtained by energy dispersive spectroscopy and shows that Ta, Mo elements are enriched in the dendrite areas, and Al, Ti, V are enriched in inter-dendrite areas. The yield strength and compress strain reach maximum (σ0.2=1221MPa, ε=9.91%) at x=0, and decrease with the addition of Al element at room temperature. Vickers hardness of the alloys improves as the Al addition.
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