Effect of C microalloying on microstructure and mechanical properties of Fe-Mn-Cr-Ni medium entropy alloy

doi:10.13251/j.issn.0254-6051.2024.06.033

Abstract

Abstract: Fe₅₀Mn₂₅Cr₁₅Ni₁₀ and (Fe₅₀Mn₂₅Cr₁₅Ni₁₀)₉₉C₁ medium-entropy alloys (MEAs) were prepared by vacuum arc melting and copper mold suction casting. Then the alloys were rolled by 80% at room temperature and annealed at 900 ℃, the effects of C microalloying on microstructure and mechanical properties of the MEAs were studied by means of XRD, SEM and EBSD. The results show that the microstructure of Fe₅₀Mn₂₅Cr₁₅Ni₁₀ and (Fe₅₀Mn₂₅Cr₁₅Ni₁₀)₉₉C₁MEAs is FCC single phase structure. With the addition of C element, the grains of the alloy are refined. The yield strength and tensile strength of the MEAs annealed at 900 ℃ for 10 min increase from 381 MPa and 586 MPa to 535 MPa and 756 MPa at room temperature (25 ℃), and from 687 MPa and 1114 MPa to 980 MPa and 1352 MPa at low temperature (-196 ℃). With the decrease of temperature from 25 ℃ to -196 ℃, the strength and ductility of (Fe₅₀Mn₂₅Cr₁₅Ni₁₀)₉₉C₁ alloy increase at the same time, resulting in better product of strength and elongation, which are mainly attributed to the appearance of fine grain strengthening, solid solution strengthening and dislocation multiplication caused by the addition of C element.

Key words: medium entropy alloy, microalloying, microstructure, mechanical properties

CLC Number:

TG113

Li Na, Sun Shugang, Yang Jianchun, Wang Qi. Effect of C microalloying on microstructure and mechanical properties of Fe-Mn-Cr-Ni medium entropy alloy[J]. Heat Treatment of Metals, 2024, 49(6): 206-210.

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