Cyclic deformation behavior and dislocation structures of [001] copper single crystals .1. Cyclic stress-strain response and surface feature

IMR OpenIR

	Cyclic deformation behavior and dislocation structures of [001] copper single crystals .1. Cyclic stress-strain response and surface feature
	Gong, B ; Wang, ZR ; Wang, ZG
	1997-04-01
发表期刊	ACTA MATERIALIA
ISSN	1359-6454
卷号	45 期号:4 页码:1365-1377
摘要	Cyclic deformation behavior of [001] copper single crystals was investigated in symmetrical pull-push Fatigue tests at the ambient temperature and with constant plastic shear strain amplitudes (gamma(pl)) in the range of 1.0 x 10(-4) to 3.0 x 10(-3). The formation and development of surface slip bands (SBs) were examined in situ by a light microscope. A rapid initial hardening stage followed by a pronounced overshooting or significant softening was found with the crystals tested at gamma(pl) greater than or equal to 4.8 x 10(-4). The cyclic stress-strain curve of [001] crystals does not show any plateau behavior. instead it follows, if corrected with the Taylor factor, the power law function for copper polycrystals. The fatigue limit, defined as the critical strain amplitude below which SBs do not form, was found to be approximately 1.7 x 10(-4), a value much higher than that for single slip oriented crystals, but very close to that for polycrystals modified by the Taylor factor. In situ observation revealed that the primary SBs appeared at the very beginning of cyclic deformation and frequently they were not persistent. The secondary (critical) SBs usually formed at the overshooting stage after rapid hardening. Deformation bands with the characteristics of kink bands were detected in the final stage of the cyclic deformation. Analysis indicated that the rapid initial cyclic hardening is caused by the formation of Lomer-Cottrell locks, while the overshooting/softening behavior is related to the operation of secondary slip or the formation of dislocation labyrinth structure. The preferred combination of primary and critical slip during cyclic deformation is also discussed in terms of dislocation reactions. (C) 1997 Acta Metallurgica Inc.
收录类别	SCI
语种	英语
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
WOS记录号	WOS:A1997WR62600005
出版者	PERGAMON-ELSEVIER SCIENCE LTD
引用统计	被引频次：69[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/321006/126875
专题	中国科学院金属研究所
作者单位	1.UNIV TORONTO,DEPT MAT SCI & MET,TORONTO,ON,CANADA 2.CHINESE ACAD SCI,MED RES INST,STATE KEY LAB FATIGUE & FRACTURE MAT,SHENYANG,PEOPLES R CHINA
推荐引用方式 GB/T 7714	Gong, B,Wang, ZR,Wang, ZG. Cyclic deformation behavior and dislocation structures of [001] copper single crystals .1. Cyclic stress-strain response and surface feature[J]. ACTA MATERIALIA,1997,45(4):1365-1377.
APA	Gong, B,Wang, ZR,&Wang, ZG.(1997).Cyclic deformation behavior and dislocation structures of [001] copper single crystals .1. Cyclic stress-strain response and surface feature.ACTA MATERIALIA,45(4),1365-1377.
MLA	Gong, B,et al."Cyclic deformation behavior and dislocation structures of [001] copper single crystals .1. Cyclic stress-strain response and surface feature".ACTA MATERIALIA 45.4(1997):1365-1377.