Stress relaxation and the structure size-dependence of plastic deformation in nanotwinned copper

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	Stress relaxation and the structure size-dependence of plastic deformation in nanotwinned copper
	L. Lu; T. Zhu; Y. F. Shen; M. Dao; K. Lu; S. Suresh
	2009
发表期刊	Acta Materialia
ISSN	1359-6454
卷号	57 期号:17 页码:5165-5173
摘要	Stress-relaxation experiments were performed on nanotwinned Cu to characterize the twin size-dependence of the activation volume and mobile dislocation density. We find that the variation of activation volume as a function of twin lamellae thickness can be captured well by a Hall-Petch-type relation. This structure size-dependence is interpreted to arise from a transition of the rate-controlling mechanism from intra-twin to twin boundary-mediated processes with decreasing twin thickness. Furthermore, we find that the exhaustion rate of mobile dislocations reduces with decreasing twin thickness. Such a twin size-dependence is attributed to the increased strain-hardening rate associated with a high density of coherent twin boundaries. Our results demonstrate that twin boundary-mediated dislocation processes can effectively promote the strain hardening and preserve mobile dislocations, leading to ultrahigh strength while retaining ductility in nanotwinned Cu. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
部门归属	[lu, lei; shen, yongfeng; lu, k.] chinese acad sci, shenyang natl lab mat sci, inst met res, shenyang 110016, peoples r china. [lu, lei; dao, ming; suresh, subra] mit, dept mat sci & engn, cambridge, ma 02139 usa. [zhu, ting] georgia inst technol, woodruff sch mech engn, atlanta, ga 30332 usa.;lu, l (reprint author), chinese acad sci, shenyang natl lab mat sci, inst met res, shenyang 110016, peoples r china;llu@imr.ac.cn
关键词	Nanoscale Twins Stress Relaxation Activation Volume Mobile Dislocation Density Plastic Deformation Kinetics Strain-rate Sensitivity Coherent Twin Boundaries Centered-cubic Metals Nano-scale Twins Nanoscale Twins Nanostructured Metals Activation Volume Single-crystals Nanocrystalline Ductility
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WOS记录号	WOS:000270691000023
引用统计	被引频次：164[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/321006/32154
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	L. Lu,T. Zhu,Y. F. Shen,et al. Stress relaxation and the structure size-dependence of plastic deformation in nanotwinned copper[J]. Acta Materialia,2009,57(17):5165-5173.
APA	L. Lu,T. Zhu,Y. F. Shen,M. Dao,K. Lu,&S. Suresh.(2009).Stress relaxation and the structure size-dependence of plastic deformation in nanotwinned copper.Acta Materialia,57(17),5165-5173.
MLA	L. Lu,et al."Stress relaxation and the structure size-dependence of plastic deformation in nanotwinned copper".Acta Materialia 57.17(2009):5165-5173.