Direct observation of deformation twinning under stress gradient in body-centered cubic metals

doi:10.1016/j.actamat.2018.05.061

CORC > 金属研究所 > 中国科学院金属研究所

	Direct observation of deformation twinning under stress gradient in body-centered cubic metals
	Jiang, BB ; Tu, AD ; Wang, H 2; Duan, HC ; He, SY ; Ye, HQ ; Du, K
刊名	ACTA MATERIALIA
	2018-08-15
卷号	155 页码:56-68
关键词	Deformation twinning BCC metals Stress gradient In situ electron microscopy
ISSN号	1359-6454
DOI	10.1016/j.actamat.2018.05.061
英文摘要	In body-centered cubic (BCC) metals, plastic deformation usually takes place by deformation twinning under high strain rate. Although numerous efforts have been conducted on deformation twinning, the twinning mechanism is still shrouded in mystery. Here, we report a direct observation of deformation twinning in BCC tantalum and niobium by the use of in situ and aberration-corrected electron microscopy. Twin lamellae grow up from coherent twin boundaries by repeatedly extruding and subsequently expanding of bulges on the twin boundaries. A substantial stress gradient is detected around twin lamellae along the twinning direction. The twin growth can be described by a self-thickening mechanism through dislocation reactions at steps on coherent twin boundaries thus absent continuous supply of dislocations. The dislocation reactions can be activated and deactivated by the transition between normal step dislocations and complementary zonal dislocations. These results provide insights to deformation twinning in bulk BCC metals. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
学科主题	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
语种	英语
WOS记录号	WOS:000439675000006
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/80020]
专题	金属研究所_中国科学院金属研究所
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Liaoning, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Chinese Acad Sci, Inst Met Res, Div Titanium Alloys, Shenyang 110016, Liaoning, Peoples R China 4.Univ Sci & Technol China, Sch Mat Sci & Engn, Hefei, Anhui, Peoples R China
推荐引用方式 GB/T 7714	Jiang, BB,Tu, AD,Wang, H,et al. Direct observation of deformation twinning under stress gradient in body-centered cubic metals[J]. ACTA MATERIALIA,2018,155:56-68.
APA	Jiang, BB.,Tu, AD.,Wang, H.,Duan, HC.,He, SY.,...&Du, K.(2018).Direct observation of deformation twinning under stress gradient in body-centered cubic metals.ACTA MATERIALIA,155,56-68.
MLA	Jiang, BB,et al."Direct observation of deformation twinning under stress gradient in body-centered cubic metals".ACTA MATERIALIA 155(2018):56-68.