Identification of MnCr2O4 nano-octahedron in catalysing pitting corrosion of austenitic stainless steels

doi:10.1016/j.actamat.2010.05.043

IMR OpenIR

	Identification of MnCr2O4 nano-octahedron in catalysing pitting corrosion of austenitic stainless steels
	Zheng, S. J.1; Wang, Y. J.1; Zhang, B.1; Zhu, Y. L.1; Liu, C.1; Hu, P.2; Ma, X. L.1
通讯作者	Ma, X. L.(xlma@imr.ac.cn)
	2010-09-01
发表期刊	ACTA MATERIALIA
ISSN	1359-6454
卷号	58 期号:15 页码:5070-5085
摘要	Pitting corrosion of stainless steels, one of the classical problems in materials science and electrochemistry, is generally believed to originate from the local dissolution in MnS inclusions, which are more or less ubiquitous in stainless steels. However, the initial location where MnS dissolution preferentially occurs is known to be unpredictable, which makes pitting corrosion a major concern. In this work we show, at an atomic scale, the initial site where MnS starts to dissolve in the presence of salt water. Using in situ ex-environment transmission electron microscopy (TEM), we found a number of nano-sized octahedral MnCr2O4 crystals (with a spinel structure and a space group of Fd (3) over barm) embedded in the MnS medium, generating local MnCr2O4/MnS nano-galvanic cells. The TEM experiments combined with first-principles calculations clarified that the nano-octahedron, enclosed by eight {1 1 1} facets with metal terminations, is "malignant", and this acts as the reactive site and catalyses the dissolution of MnS. This work not only uncovers the origin of MnS dissolution in stainless steels, but also presents an atomic-scale evolution in a material's failure which may occur in a wide range of engineering alloys and biomedical instruments serving in wet environments. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
关键词	Scanning/transmission electron microscopy (STEM) Corrosion Catalysis Electrochemistry Stainless steel
资助者	National Natural Science Foundation of China ; National Basic Research Program of China ; Chinese Academy of Sciences ; CAS/SAFEA
DOI	10.1016/j.actamat.2010.05.043
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China ; National Basic Research Program of China[2009CB623705] ; Chinese Academy of Sciences ; CAS/SAFEA
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000280570500017
出版者	PERGAMON-ELSEVIER SCIENCE LTD
引用统计	被引频次：114[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/100083
专题	中国科学院金属研究所
通讯作者	Ma, X. L.
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China 2.Queens Univ Belfast, Sch Chem & Chem Engn, Belfast BT9 5AG, Antrim, North Ireland
推荐引用方式 GB/T 7714	Zheng, S. J.,Wang, Y. J.,Zhang, B.,et al. Identification of MnCr2O4 nano-octahedron in catalysing pitting corrosion of austenitic stainless steels[J]. ACTA MATERIALIA,2010,58(15):5070-5085.
APA	Zheng, S. J..,Wang, Y. J..,Zhang, B..,Zhu, Y. L..,Liu, C..,...&Ma, X. L..(2010).Identification of MnCr2O4 nano-octahedron in catalysing pitting corrosion of austenitic stainless steels.ACTA MATERIALIA,58(15),5070-5085.
MLA	Zheng, S. J.,et al."Identification of MnCr2O4 nano-octahedron in catalysing pitting corrosion of austenitic stainless steels".ACTA MATERIALIA 58.15(2010):5070-5085.