Effect of Al content on microstructure and properties of hot rolled FeMnCoCr high entropy alloy

doi:10.13251/j.issn.0254-6051.2022.05.007

Abstract

Abstract: Effect of Al content on microstructure, deformation mechanism and tensile properties of the (Fe₅₀Mn₃₀Co₁₀Cr₁₀)_100-xAl_x high entropy alloys was studied. The (Fe₅₀Mn₃₀Co₁₀Cr₁₀)_100-xAl_x cast alloys were melted by a vacuum electric arc furnace, and then hot rolled and water quenched with a reduction rate of 80%. The microstructure of the alloy was analyzed by using SEM and EBSD. The results show that with the increase of Al content (atom fraction, the same below) from 0% to 6%, the microstructure of the hot rolled and quenched alloy changes from FCC+HCP dual phase to FCC single phase, and BCC phase occurs when Al content is 8%. With the increase of Al content from 0% to 6%, the TRIP effect is inhibited, but the TWIP effect enhances obviously, the yield strength of the alloy changes a little, the tensile strength decreases slightly, while the elongation after fracture increases significantly. When the Al content is 6%, the elongation of the high entropy alloy reaches the highest, which is 79%.

Key words: FeMnCoCr high entropy alloy, Al content, microstructure, TRIP effect, TWIP effect, tensile properties

CLC Number:

TG139

Zhao Sijie, Li Hang, Niu Lichong, Li Jie, Feng Yunli. Effect of Al content on microstructure and properties of hot rolled FeMnCoCr high entropy alloy[J]. Heat Treatment of Metals, 2022, 47(5): 47-52.

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