Formation mechanism of (Mn,Cr)Te inclusion in Fe-13Cr stainless steel and its doped atomic structure

ABSTRACT

In this study, the formation mechanism of telluride inclusion in Te-containing Fe-13Cr stainless steel was discussed via equilibrium phase diagram calculation, nucleation kinetics, and inclusion characterisation. The first principles method was used to discuss the effects of Fe and Cr atoms on the stability, metallicity, and magnetism of MnTe crystal structure. The observed inclusions are mainly single-particle spherical MnTe and irregular MnTe-MnS composite inclusion (TSCI), Cr can dissolve in MnTe to form (Mn,Cr)Te. The atomic ratio of tellurium to sulphur, Te/S_(at.%), in composite inclusions determines the nucleation order of MnTe and MnS in composite inclusions. (Mn_0.9375, Cr_0.0625) Te is the most likely stable doped crystal structure. Fe can increase the metallicity of MnTe, while Cr atoms reduce the metallicity of MnTe. The solid solution of Fe leads to an increase in ferromagnetism in Mn-Fe-Cr-Te and Mn-Fe-Te systems, while Cr can maintain good ferromagnetism in Mn-Cr-Te systems

KEYWORDS:

• Telluride
• sulphide
• stainless steel
• MnTe-MnS
• composite inclusion
• phase diagram
• doped structure
• first-principle method

Acknowledgements

One of the authors, Hui Liu, thanks Qianren Tian (a doctoral student at Shanghai University) for discussing the nucleation kinetics of inclusions and providing him with inspiration for participating in this research work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Natural Science Foundation of Anhui Province: [Grant Number 2108085QE216]; Natural Science Foundation of the Anhui Higher Education Institutions: [Grant Number 2022AH050243]; Anhui Jianzhu University PhD Startup Fund: [Grant Number 2020QDZ04].