Understanding creep mechanisms of a Cu-Cr-Nb alloy by testing under constant structure conditions. (1st January 2021)

• Record Type: Journal Article
• Authors: Zhang, M.; Gibeling, J.C.
• Is Part Of: Scripta materialia. Number 190(2021)
• Page Start: 131
• Page End: 135
• Publication Date: 2021-01-01
• Subjects: Creep -- Copper alloys -- Thermally activated processes -- Dislocation structure -- Dislocation-particle interaction; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2020.08.036
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: Stress reduction creep tests conducted on a Cu-Cr-Nb alloy (GRCop-84) at 923 K have confirmed local dislocation climb to be the rate-controlling deformation mechanism. The activation energy of creep was measured to be consistent with that of self-diffusion in Cu matrix. An internal back stress of approximately -9 MPa was identified to act on the rate-controlling dislocations, which is believed to be the sum of the back stress for dislocation-particle interaction and the forward stress for dislocation-dislocation interaction. This back stress, however, does not lead to a true threshold in the framework of thermally activated dislocation motion. Graphical abstract: Image, graphical abstract