Deformation mechanisms in hexagonal close-packed high-entropy alloys

Published on May 4, 2021in Journal of Applied Physics2.286
· DOI :10.1063/5.0045414
Z. Wang (TUT: Taiyuan University of Technology), M. L. Bao1
Estimated H-index: 1
(TUT: Taiyuan University of Technology)
+ 3 AuthorsJunwei Qiao29
Estimated H-index: 29
(TUT: Taiyuan University of Technology)
Single-phase hexagonal close-packed structure of the ScYLaGdTbDyHoErLu high-entropy alloy was studied in detail. The applicability of the rule of mixture was analyzed with respect to the lattice constant, mechanical parameters, elastic properties, melting point, and hardness of the alloy. Significant tension-compression asymmetry has been found and explained by the strength differential effect during the uniaxial tests. Numerous deformation twins and high densities of stacking faults can be observed from the morphological characterization by a transmission electron microscope, which governs the main deformation mechanism during the plastic deformation in the current high-entropy alloy.
#1Kunda Yao (Liaoning University of Technology)H-Index: 1
#2Liang Liu (Liaoning University of Technology)H-Index: 4
Last. Wen Chen (UMass: University of Massachusetts Amherst)H-Index: 104
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Abstract The current research of high-entropy alloys (HEAs) is mainly focused on simple solid-solution alloys or alloys with precipitation strengthening phases. In the present work, we developed a series of high-entropy intermetallic compounds (HEICs). In particular, the multi-principal element Fe0.75Co0.75Ni0.75Cu0.75TiZrHf with B2 ordering shows an ultrahigh compressive yield strength of 2.25 GPa and a fracture strength of 2.52 GPa. The developed HEIC also demonstrates exceptional high-tempera...
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The formation of octonary DyErGdHoLuScTbY and senary DyGdHoLaTbY and ErGdHoLaTbY high-entropy alloys (HEAs) with the hexagonal close-packed (HCP) structure was reported in this study. Experiments using scanning electron microscopy and x-ray diffraction confirmed the single HCP solid solution in the as-cast state for these three HEAs if the presence of minor rare-earth oxides due to contamination from processing is ignored. The measured compressive yield stress values for these HEAs at room tempe...
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#1S. Vrtnik (University of Ljubljana)H-Index: 11
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Abstract Rare-earth (RE) based hexagonal high-entropy alloys (HEAs) containing elements from the heavy half of the RE series (from Gd to Lu) are considered as prototypes of an ideal HEA, stabilized by the entropy of mixing with completely random distribution of the elements on an almost undistorted hexagonal close-packed (hcp) lattice. Here we present a study of the Ce-Gd-Tb-Dy-Ho hexagonal HEA (abbreviated as HEA-Ce), where a light-RE element Ce is alloyed with four heavy-RE elements. Since the...
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