【摘 要】
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Equiatomic CrMnFeCoNi high entropy alloy prepared by powder metallurgy was remelted by laser.The relative density and mi-crostructure of fusion zone are evaluated.The nanoindentation tests are conducted to reveal the hardness difference of dendrite arms a
【机 构】
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Shanghai Key Laboratory of Materials Laser Processing and Modification,Shanghai Jiao Tong University
论文部分内容阅读
Equiatomic CrMnFeCoNi high entropy alloy prepared by powder metallurgy was remelted by laser.The relative density and mi-crostructure of fusion zone are evaluated.The nanoindentation tests are conducted to reveal the hardness difference of dendrite arms and in-terdendritic areas.Tensile tests are conducted to assess the mechanical properties of remelted HEA.After laser remelting,the number and morphology of voids changed significantly.Dendritic structure with face-centered cubic phase form in the fusion zone.Fe,Cr and Co are en-riched in dendrite arm,while Mn and Ni are enriched in interdendritic area.Elements segregation led to a nanohardness difference between dendrite arm and interdendritic area.Local deformation occurs in interdendritic area during tensile tests and results in a fracture with direc-tionality.
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