Understanding creep mechanisms of a Cu-Cr-Nb alloy by testing under constant structure conditions

SCRIPTA MATERIALIA

卷:190

Article

Zhang, M.¹  Gibeling, J. C.¹ 

[1] Univ Calif Davis, Dept Mat Sci & Engn, One Shields Ave, Davis, CA 95616 USA

关键词: Creep;    Copper alloys;    Thermally activated processes;    Dislocation structure;    Dislocation-particle interaction;   

DOI  :  10.1016/j.scriptamat.2020.08.036

来源: Elsevier

【 摘 要 】

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. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free