The mechanical properties and microstructure evolution of AlCoCrFeNi High-Entropy Alloys (HEAs) at different strain rates and temperatures were investigated. High strain rate experiments are performed by the split-Hopkinson pressure bar (SHPB) at strain rates of 500,1500 and 2500 s⁻¹ at three different temperatures (27, 250 and 500 °C). And Gleeble machine was used to carry out the experiment at high temperatures (500, 750 and 900 °C) under quasi-static compression condition. Stress-strain curves indicated flow stress is increased by raising the strain rate at all temperatures. Microstructure observation of the deformed samples show no any dynamically recrystallized (DRX) occurred at tested condition. However, it is several transgranular cracks are observed in tested samples, the number of the cracks are decreased by rising the temperatures. At temperature higher than the 500 °C under quasi-static condition DRX microstructure with unrecrystallized coarse structure with necklace morphology is observed in deformed sample. The average grain size in the DRX region is around 0.5 μm. It is worth to mention, DRX grains do not show preferred orientations at formed necklace structure.

研究了 AlCoCrFeNi 高熵合金 (HEAs) 在不同应变速率和温度下的力学性能和微观结构演变。高应变率实验由分裂霍普金森压力棒 (SHPB) 在 500,1500 和 2500 s ^{-1的应变率下进行} 在三种不同的温度（27、250 和 500 °C）下。并使用 Gleeble 机在准静态压缩条件下进行高温（500、750 和 900 ℃）实验。应力-应变曲线表明，在所有温度下，通过提高应变率都会增加流动应力。变形样品的微观结构观察表明在测试条件下没有发生任何动态再结晶（DRX）。然而，在测试样品中观察到几个穿晶裂纹，裂纹的数量随着温度的升高而减少。在高于 500°C 的准静态条件下，在变形样品中观察到具有未再结晶粗大结构和项链形态的 DRX 微观结构。DRX 区域的平均晶粒尺寸约为 0.5 μm。值得一提的是，