Observing Dislocations Transported by Twin Boundaries in Al Thin Film: Unusual Pathways for Dislocation-Twin Boundary Interactions

Kou Z.; Feng T.; Lan S.; Tang S.; Yang L.; Yang Y.; Wilde G.

Research article (journal)

Abstract

Twins are generally regarded as obstacles to dislocations in face-centered cubic metals and can modify individual dislocations by locking them in twin boundaries or obliging them to dissociate. Through in situ tensile experiments on Al thin film in a transmission electron microscope, we report a dynamic process of dislocations being transported by twin lamella via periodic twinning and detwinning at the atomic scale. Following this process, a 60° dislocation first transforms into a sessile step of the twin boundary, then migrates under stress as a step and finally reverts back into a 60° dislocation. Our results reveal a novel evolution route of dislocations by a dislocation-twin interaction where the twins act as transport vehicles rather than as obstacles. The potential implications of this mechanism on toughening are also discussed.

Details zur Publikation

Publisher:
Release year: 2022
Publishing company: American Chemical Society
Language in which the publication is written: English
Link to the full text: https://api.elsevier.com/content/abstract/scopus_id/85135768110