Local microstructure evolution of a V-containing Fe-Cr-Ni-Mo weld metal subjected to post-weld heat treatment

doi:10.1016/j.matchar.2023.113096

IMR OpenIR

	Local microstructure evolution of a V-containing Fe-Cr-Ni-Mo weld metal subjected to post-weld heat treatment
	Sun, Jian 1; Liu, Jingwu 1,2; Wei, Shitong 1; Lu, Shanping 1
通讯作者	Lu, Shanping(shplu@imr.ac.cn)
	2023-09-01
发表期刊	MATERIALS CHARACTERIZATION
ISSN	1044-5803
卷号	203 页码:20
摘要	The high-strength steels are widely used in modern shipbuilding and marine facilities. However, welding of >900 MPa grade steels is particularly challenging owing to the lack of understanding of fine microstructure for the weld metal (WM). The present investigation is mainly focused on a V-containing Fe-Cr-Ni-Mo WM fabricated by gas metal arc welding (GMAW) in aspects of localized microstructure evolution during post-weld heat treatment (PWHT). Microanalysis of the localized microstructure of inter-dendritic regions (IDRs) and dendrite core region (DCRs) for WMs was conducted by transmission electron microscopy (TEM), transmission kikuchi diffraction (TKD) and atom probe tomography (APT), complimented by nanoindentation hardness testing. It is found that the microstructure of WM in as-welded (AW) and PWHT condition was characterized by elongated martensitic laths with high-density dislocations in IDRs, while that in DCRs was coarse bainitic microstructure with relatively fewer dislocations. Most of retained austenite (RA) formed during cooling after welding was decorated martensite lath boundaries within IDRs owing to the segregation of austenite stabilizing elements after solidification. For PWHT condition, more numerous and smaller nano-scale MC carbides were observed in IDRs compared to DCRs. Furthermore, V atoms were mainly responsible for the nucleation of nano-scale MC carbides, and the growth and coarsening process of them were mainly controlled by diffusion of Mo atoms. Besides, the RA could also decompose into nano-scale MC carbides during PWHT. The IDRs of the PWHT specimens showed the average nanohardness value of 7.4 & PLUSMN; 2.3 GPa, which was higher than that of the DCRs (4.0 & PLUSMN; 0.2 GPa).
关键词	Weld metal Post-weld heat treatment Inter-dendritic segregation Retained austenite
资助者	National Natural Science Foundation of China ; China Postdoctoral Science Foundation ; Major R amp; D Project of Liaoning Province ; Liaoning Provincial Doctoral Initiation Fund Project ; Young Talent Project of Shenyang National Research Center for Materials Science
DOI	10.1016/j.matchar.2023.113096
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[52101060] ; China Postdoctoral Science Foundation[2022M713213] ; Major R amp; D Project of Liaoning Province[2020JH1/10100001] ; Liaoning Provincial Doctoral Initiation Fund Project[2022-BS-008] ; Young Talent Project of Shenyang National Research Center for Materials Science[2022-SYNL]
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering ; Materials Science, Characterization & Testing
WOS记录号	WOS:001032093900001
出版者	ELSEVIER SCIENCE INC
引用统计
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/178679
专题	中国科学院金属研究所
通讯作者	Lu, Shanping
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, 72 Wenhua Rd, Shenyang 110016, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, 72 Wenhua Rd, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Sun, Jian,Liu, Jingwu,Wei, Shitong,et al. Local microstructure evolution of a V-containing Fe-Cr-Ni-Mo weld metal subjected to post-weld heat treatment[J]. MATERIALS CHARACTERIZATION,2023,203:20.
APA	Sun, Jian,Liu, Jingwu,Wei, Shitong,&Lu, Shanping.(2023).Local microstructure evolution of a V-containing Fe-Cr-Ni-Mo weld metal subjected to post-weld heat treatment.MATERIALS CHARACTERIZATION,203,20.
MLA	Sun, Jian,et al."Local microstructure evolution of a V-containing Fe-Cr-Ni-Mo weld metal subjected to post-weld heat treatment".MATERIALS CHARACTERIZATION 203(2023):20.