Mechanism of Dynamic Strain-Induced Ferrite Transformation in a 3Mn-0.2C Medium Mn Steel

doi:10.11900/0412.1961.2021.00192

IMR OpenIR

	Mechanism of Dynamic Strain-Induced Ferrite Transformation in a 3Mn-0.2C Medium Mn Steel
	Sun Yi 1,2; Zheng Qinyuan 2,3; Hu Baojia 2,3; Wang Ping 1; Zheng Chengwu 2,3; Li Dianzhong 2,3
通讯作者	Wang Ping(wping@epm.neu.edu.cn) ; Zheng Chengwu(cwzheng@imr.ac.cn)
	2022-05-01
发表期刊	ACTA METALLURGICA SINICA
ISSN	0412-1961
卷号	58 期号:5 页码:649-659
摘要	Medium Mn steels (MMSs) have Mn contents of 3%-12% (mass fraction), and have been energetically investigated as the most promising candidates of the third-generation advanced high-strength steel. Their phase transformations and microstructures during various heat treatments and thermomechanical processes have received wide attention with the purpose to achieve an optimal balance of cost-efficient alloying compositions and mechanical properties. The aim of this work is to investigate the microstructural behavior of deformation-induced ferrite transformation (DIFT), starting from austenite, which occurs in MMS. Then, improved understandings of the formation of ultrafine ferrite via the DIFT and conservation of this microstructure during the post-deformation period can be obtained. For this purpose, a 3Mn-0.2C MMS with lower contents of alloying elements was selected. Microstructures and alloying element distributions of the thermomechanically processed samples were analyzed via EBSD and EPMA. The results showed that the DIFT occurred in the thermomechanically processed 3Mn-0.2C MMS in the alpha + gamma region. Characteristic multiphase microstructures consisting isolated martensite and fine-grained equiaxed ferrite concomitant with fine islands of retained austenite dispersed between ferrite grains can be obtained. During the DIFT, the enhanced nucleation of ferrite at alpha/gamma interfaces can not only increase the ferrite nucleation density but also facilitate extensive impingement among the neighboring grains. Formation of ultrafine ferrite via the DIFT in MMS can be interpreted in terms of unsaturated nucleation and limited growth. In addition, partitioning of Mn between the ultrafine ferrite and austenite is accelerated during the DIFT such that a large number of Mn-enriched fine islands of austenite are left untransformed at the alpha/alpha grain boundaries or at triple junctions. These islands of austenite are considered to play critical roles not only for obtaining retained austenite at room temperature but also for conserving the ultrafine microstructure of the DIFT during the post-deformation processing.
关键词	hot deformation ultra-fine grained ferrite Mn partitioning deformation induced ferrite transformation medium Mn steel
资助者	National Natural Science Foundation of China
DOI	10.11900/0412.1961.2021.00192
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[52071322] ; National Natural Science Foundation of China[51771192] ; National Natural Science Foundation of China[U1708252]
WOS研究方向	Metallurgy & Metallurgical Engineering
WOS类目	Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000787207700006
出版者	SCIENCE PRESS
引用统计	被引频次：1[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/321006/172720
专题	中国科学院金属研究所
通讯作者	Wang Ping; Zheng Chengwu
作者单位	1.Northeastern Univ, Key Lab Electromagnet Proc Mat, Minist Educ, Shenyang 110819, Peoples R China 2.Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China 3.Univ Sci & Technol China, Sch Mat Sci & Engn, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Sun Yi,Zheng Qinyuan,Hu Baojia,et al. Mechanism of Dynamic Strain-Induced Ferrite Transformation in a 3Mn-0.2C Medium Mn Steel[J]. ACTA METALLURGICA SINICA,2022,58(5):649-659.
APA	Sun Yi,Zheng Qinyuan,Hu Baojia,Wang Ping,Zheng Chengwu,&Li Dianzhong.(2022).Mechanism of Dynamic Strain-Induced Ferrite Transformation in a 3Mn-0.2C Medium Mn Steel.ACTA METALLURGICA SINICA,58(5),649-659.
MLA	Sun Yi,et al."Mechanism of Dynamic Strain-Induced Ferrite Transformation in a 3Mn-0.2C Medium Mn Steel".ACTA METALLURGICA SINICA 58.5(2022):649-659.