From glissile to sessile: Effect of temperature on 〈110〉 dislocations in perovskite materials. (15th July 2016)

• Record Type: Journal Article
• Authors: Hirel, Pierre; Carrez, Philippe; Cordier, Patrick
• Is Part Of: Scripta materialia. Volume 120(2016)
• Page Start: 67
• Page End: 70
• Publication Date: 2016-07-15
• Subjects: Perovskites -- Dislocation -- Climb -- Fracture -- Computer simulations; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2016.04.001
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: In perovskite-type strontium titanate (SrTiO3 ) 〈110〉 dislocations, which are the main carriers of plastic flow at low temperature, lose their mobility as temperature increases, leading to brittle failure above 1050 K. We present theoretical evidence for a change in their core structure into a sessile, climb-dissociated configuration at high temperature. This mechanism is shown to operate in both SrTiO3 and MgSiO3, indicating that it may be a general feature of perovskite-type materials. It follows that the activity of the 〈110〉 slip system depends critically on the strain rate-temperature couple, ε ̇ T . Graphical abstract: