Near atomic-scale comparison of passive film on a 17 wt% Cr-added 18 wt% Mn steel with those on typical austenitic stainless steels

SCRIPTA MATERIALIA

卷:203

Article

Kim, Eun Tae¹  Ishtiaq, Muhammad^2,3  Han, Jong Chan¹  Ko, Kwang Kyu²  Bae, Hyo Ju²  Sung, Hyokyung²  Kim, Jung Gi²  Seol, Jae Bok² 

[1] SK Hynix Inc R&D, Incheon 17336, South Korea

[2] Gyeongsang Natl Univ GNU, Dept Mat Engn & Convergence Technol, Jinju 52828, South Korea

[3] Univ Punjab, Inst Met & Mat Engn, Lahore, Pakistan

关键词: Stainless steels;    High-Mn steel;    Corrosion resistance;    Passive films;    Atom probe tomography;   

DOI  :  10.1016/j.scriptamat.2021.114112

来源: Elsevier

【 摘 要 】

The passive films on typical stainless steels (SS) and on a newly developed high-Cr (17 wt%)-added 18 wt%-Mn steel (HCr-HMnS) were compared by Cs-corrected scanning transmission electron microscopy and atom probe tomography. Although the passive films of all samples having similar Cr contents had the same thickness, unprecedented hexagonal wurtzite MnO inside the passive film of HCr-HMnS specimen was susceptible to corrosion cracking; this was not observed in the SS samples. This MnO caused crack formation during potentiodynamic polarization test, suggesting that reducing the harmful MnO by adding Mo and Ni facilitates the development of high-Mn base SS materials . Furthermore, higher MoO 2 composition of the passive films on 316 type austenitic SS than 304 type series might would result in primarily the improved pitting resistance. (c) 2021 The Author(s). Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

【 授权许可】

Free