Phase transformation and precipitation behaviors of Mn18Cr18N austenitic stainless steel during equilibrium solidification

doi:10.13251/j.issn.0254-6051.2020.03.016

Abstract

Abstract:

The phase transformation and precipitation behaviors were investigated by using Thermo-calc software in the Fe-(16-19)Cr-(16-19)Mn-(0.4-0.7)N-(0.04-0.1)C-(0.1-0.4)Si-(0.1-0.4)Ni multi-element system relevant to Mn18Cr18N austenitic stainless steel during solidification. The vertical sections of phase diagram of this system were calculated by using the TCFE9 database. Based on these vertical sections, the influence of different elements was analyzed in the phase transformations during solidification and a diagram of the phase-transformation path of Mn18Cr18N austenitic stainless steel was obtained during equilibrium solidification. The test results show that increasing C, N, Si and Ni content can enlarge the stable region of γ phase and the effect of Cr and Mn on stabilizing ferrite is obvious. Phase-transformation path and M₂₃C₆ precipitation temperature mainly depend on C content; Cr₂N precipitation temperature mainly depends on N content and σ precipitation temperature mainly depends on Cr content.

Key words: Mn18Cr18N austenitic stainless steel, phase diagram calculation, solidification mode, Thermo-calc software

CLC Number:

TG142.71

Wang Yinghu. Phase transformation and precipitation behaviors of Mn18Cr18N austenitic stainless steel during equilibrium solidification[J]. HTM, 2020, 45(3): 78-85.

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