In this work,high strength and ductile Al0.5Cr0.8CoFeNi2.5V0.2 high-entropy alloys(HEAs)were fabricated by the selec-tive laser melting(SLM)technique.After orthogonal experiments,it was verified that a wide SLM processing parameter window can be used to produce crack-free samples for the investigated HEAs.All the printed HE A samples exhibit good densification higher than 98.3％.It was found that obvious epitaxial growth leads to the formation of the cylindrical and equiaxed ordered face-centered cubic(FCC)crystals,displaying the characteristics of sub-cylindrical and sub-cellular microstructures.The low-angle grain boundaries(LAGBs)prefer appearing around subgrain structures,while the high-angle grain boundaries(HAGBs)tend to form around coarse grains.Two HEA samples with high and low apparent densities were selected to observe their mechanical properties,which exhibit Vickers hardness higher than 263 HV and do not fail during compression.With increasing densification,the strength gradually rises.According to the engineering stress-strain curves during compression,the yield strength is higher than 530 MPa,while the strength near 40％engineering strain is larger than 1840 MPa.During deformation,a large density of dislocations becomes popular within subgrain structures together with the pre-existing dislocations from rapid solidification,leading to the formation of planar and cross slip bands.Within coarse cylindrical crystals,some deformation twins are also induced together with the appearance of a distinct copper-type texture during deformation.As a result,the as-printed samples display better mechanical properties than the as-cast counterpart.The present studies provide a very good HEA candidate for the SLM process,but more work should be conducted to achieve excellent comprehensive properties.

Yao Yan;Wei-Dong Song;Ke-Feng Li;Kang Zhao;Tong-Tong Sun;Kai-Kai Song;Jian-Hong Gong;Li-Na Hu

Shenzhen Research Institute of Shandong University,Shenzhen 518057,China;State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China;Guangdong Institute of Materials and Processing,Guangdong Academy of Sciences,Guangdong University,Guangzhou 510650,China;School of Mechanical,Electrical and Information Engineering,Shandong University,Weihai 264209,China;Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education),Shandong University,Jinan 250061,China

金属学报（英文版）

[1]Yao Yan;Wei-Dong Song;Ke-Feng Li;Kang Zhao;Tong-Tong Sun;Kai-Kai Song;Jian-Hong Gong;Li-Na Hu-.Microstructural Features and Mechanical Behaviors of Al0.5Cr0.8CoFeNi2.5V0.2 High-Entropy Alloys Fabricated by Selective Laser Melting Technique)[J].金属学报（英文版）,2022(10):1591-1606

5Cr0,8CoFeNi2

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