Direct observation of dislocation formation and plastic anisotropy in Nb2AlC MAX phase using in situ nanomechanics in transmission electron microscopy. (August 2017)

• Record Type: Journal Article
• Authors: Kabiri, Yoones; Schrenker, Nadine; Müller, Julian; Mačković, Mirza; Spiecker, Erdmann
• Is Part Of: Scripta materialia. Number 137(2017)
• Page Start: 104
• Page End: 108
• Publication Date: 2017-08
• Subjects: Transmission electron microscopy (TEM) -- Nanoindentation -- Dislocation nucleation -- Mechanical properties -- MAX phases; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2017.04.015
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: We report on the direct observation of nucleation and propagation of basal plane dislocations in Nb2 AlC, a member of MAX phases, using nanomechanical testing inside a transmission electron microscope. Different loading directions with respect to the basal plane resulted in completely different plastic response due to the pronounced anisotropy of the layered crystal. Discrete dislocation activities were correlated to distinct events in the force-displacement curves. In situ observations together with post-mortem contrast analyses of deformed regions show no indication of cross-slip or entanglement of dislocations during the indentations. Graphical abstract: