Cyclic deformation behavior of Cu-30% Zn single crystals oriented for single slip - II. Dislocation structures

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	Cyclic deformation behavior of Cu-30% Zn single crystals oriented for single slip - II. Dislocation structures
	B. Gong; Z. Wang; Z. G. Wang
	1998
发表期刊	Acta Materialia
ISSN	1359-6454
卷号	47 期号:1 页码:317-324
摘要	The dislocation structures of Cu-30% Zn single crystals cyclically deformed at gamma(pl) = 3.8 x 10(-5)-6.4 x 10(-3) were studied through transmission electron microscopy in order to understand the cyclic deformation mechanisms of the material. It has been shown that the fatigue dislocation structures have two basic configurations depending on the strain amplitude applied. At low strain amplitudes (gamma(pl) <3 x 10(-4)), the dislocation structure is characterized by dislocation segments and multipoles, very similar to that formed in stage I of tensile deformation in the same material. At high strain amplitudes (gamma(pl) >3.0 x 10(-4)), however, the dislocation structure is dominated by planar dislocation loops and tangles; in this case a small amount of dislocation multipoles and a special zigzagged structure are also detected. Secondary slips were found to be activated from a very low strain amplitude (gamma(pl) = 3.8 x 10(-5)). This behavior is attributed to (i) the lower stress for dislocation generation compared with cyclic dow stresses and (ii) heterogeneous deformation at low strain amplitudes that results in a weak effect of local latent hardening. Cyclic deformation mechanisms at low and high strain amplitudes have been discussed in terms of the motion of dislocation multipoles and the dislocation reactions between the primary and secondary slip systems. The critical strain amplitude for the transition of the deformation mechanisms has been also theoretically determined to be 3 x 10(-4), in good agreement with results on the cyclic deformation response and the features of dislocation structures. The formation of specific dislocation structures such as the zigzagged structure has been discussed with detailed dislocation mechanisms. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.
部门归属	univ toronto, dept met & mat sci, toronto, on, canada. chinese acad sci, inst met res, state key lab fatigue & fracture, shenyang, peoples r china.;wang, z (reprint author), univ toronto, dept met & mat sci, toronto, on, canada
关键词	Stress-strain Response Copper Cu-16 Alloy Amplitudes Fatigue
URL	查看原文
WOS记录号	WOS:000077996000030
引用统计	被引频次：16[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/321006/37663
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	B. Gong,Z. Wang,Z. G. Wang. Cyclic deformation behavior of Cu-30% Zn single crystals oriented for single slip - II. Dislocation structures[J]. Acta Materialia,1998,47(1):317-324.
APA	B. Gong,Z. Wang,&Z. G. Wang.(1998).Cyclic deformation behavior of Cu-30% Zn single crystals oriented for single slip - II. Dislocation structures.Acta Materialia,47(1),317-324.
MLA	B. Gong,et al."Cyclic deformation behavior of Cu-30% Zn single crystals oriented for single slip - II. Dislocation structures".Acta Materialia 47.1(1998):317-324.