The low-temperature deformation behavior of VNbTa entropy alloys with equiatomic ratio and body centered cubic structure was systematically investigated through low-temperature tensile testing.The results indicate that the alloy has excellent low-temperature strain hardening ability,which results in a fracture elongation of 27%and a tensile strength of up to 1930 MPa.Microstructural evolution analysis reveals that the twisted bands and{112}<111>deformation twins formed during the deformation process effectively regulate shear strain and promote the improvement of alloy plasticity and strength.In addition,screw dislocation entanglement,dislocation bands,and their interaction also contribute significantly to the strength and work hardening ability of the alloy.Therefore,the excellent low-temperature mechanical properties of VNbTa medium entropy alloy are attributed to the synergistic effect of{112}<111>deformation twins,twisted bands,screw dislocation slip and interaction.
关键词
中熵合金/拉伸力学性能/低温/延-脆转变
Key words
medium-entropy alloys/tensile mechanical properties/cryogenic temperature/ductile to brittle transition
维普
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