Dissociated dislocations in confined plasticity

被引:24
作者
Douin, J. [1 ]
Pettinari-Sturmel, F. [1 ]
Coujou, A. [1 ]
机构
[1] CNRS, CEMES, F-31055 Toulouse, France
关键词
confined plasticity; dislocations; dissociation; dislocation dynamics; superalloys;
D O I
10.1016/j.actamat.2007.08.006
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The influence of the dissociation of dislocations when plasticity is localized in small volumes is illustrated for the case of gamma/gamma ' superalloys. Dissociated dislocations constrained to move through channels present three different types of behavior. Dislocation dynamic simulations in a face-centered cubic crystal show these three types of behavior and give the conditions under which a dissociated dislocation can move through a channel bordered by impenetrable obstacles. We show that a partial dislocation needs a lower stress for its motion than a perfect one in a significant domain of stress orientations. The consequences of the uncorrelated motion of one of the partials, leading to the formation of large stacking faults, are also examined. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
引用
收藏
页码:6453 / 6458
页数:6
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