Strain nonuniformities and plastic instabilities
نویسندگان
چکیده
Self-organization of dislocation structures, slip line and band patterning, and macroscopic plastic instabilities are typical manifestations, at different scales of observation, of nonlinear cooperative phenomena. This general aspect is discussed with emphasis on the relations between the dynamic properties of dislocations, their collective behavior, the local plastic properties of a material and the conditions for the onset of nonuniform plastic flow. Instabilities can be classified into two main categories which are illustrated by two particular examples: Lüders bands (instabilities of the h type) and the Portevin-Le Chatelier effect (instabilities of the S type). Revue Phys. Appl. 23 (1988) 573-583 AVRIL 1988, 1
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