Mechanical properties and deformation mechanisms of Al0.1CoCrFeNi high-entropy alloys
CHEN Gang1, WANG Lu1, YANG Jing2, LI Qiang1, LYU Pin1, MA Sheng-guo1,2,3
1. Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan 030024, China;
2. Shanxi Key Laboratory of Material Strength and Structural Impact, Taiyuan University of Technology, Taiyuan 030024, China;
3. National Demonstration Center for Experimental Mechanics Education, Taiyuan University of Technology, Taiyuan 030024, China
Abstract：The Al0.1CoCrFeNi high-entropy alloy (HEA) was melted by vacuum magnetic levitation, and quasi-static tensile experiments were performed by using an INSTRON mechanical testing system. The crystal structure, surface morphology, composition, microstructure, hardness, and creep behavior of the samples before and after the experiment were analyzed by X-ray diffraction, optical microscopy, scanning electron microscopy, transmission electron microscopy, and nanoidentation. Results reveal that after tensile deformation, the alloy has an excellent strength-ductility combination, a significant strain-hardening effect, and an improved creep resistance. The fracture mode of sample is the typical microvoid accumulation fracture; there are a lot of microbands (the band width is about 200-300nm) inside the grains. The excellent strain-hardening ability is believed to be originated from the microband-induced plasticity effect during tensile loading.
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