Abstract The CoCrCuFeNi high-entropy alloy was prepared by vacuum hot-press sintering. The effects of hot-pressing time and pressure on the microstructure and mechanical properties of the CoCrCuFeNi high-entropy alloy were studied. The results show that when the pressure is 10 MPa, all high-entropy alloys contain dual FCC phases and a small amount of Cr-rich phase. With the increase of hot-pressing time, the size of the Cr-rich phase increases and the compressive strength and hardness of the high-entropy alloy first increase and then decrease. When the hot-pressing time is 1.5 h, and the pressure increases from 10 MPa to 30 MPa, the separation phenomenon of Cu-rich FCC phase and Cu-poor phase disappears in the alloy. With the increase of hot-pressing pressure, the compressive strength of the high-entropy alloy first increases and then decreases, but there is no significant change in hardness. When the hot-pressing time is 1.5 h and the pressure is 20 MPa, The alloy has the highest compressive strength of 1 229 MPa and a hardness (HV) of 3 136 MPa.
ZHAO Zhenguo,ZHU Heguo. Effects of vacuum hot-pressing time and pressure on the microstructure and mechanical properties of CoCrCuFeNi high-entropy alloy[J]. Materials Science and Engineering of Powder Metallurgy, 2022, 27(2): 180-186.
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