Dissociated dislocations in confined plasticity

✍ Scribed by J. Douin; F. Pettinari-Sturmel; A. Coujou

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 428 KB
• Volume: 55
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2007.08.006

✦ Synopsis

The influence of the dissociation of dislocations when plasticity is localized in small volumes is illustrated for the case of c/c 0 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.