Creep of stress-relieved Zry-4 at 673 K

Abstract

Creep data, at 673 K, up to times of about 400 h and stresses between 120 and 242 MPa, in flat specimens of Zry-4 stress-relieved for 1 h at 813 K, are presented. The creep curves, when viewed in a log σ−log ge diagram, show a scaling behaviour leading to a master curve similar to the one obtained in 64% cold-worked material. The data are interpreted in terms of a constitutive equation based on a creep model involving jog-drag and cell-formation, and the apparent activation energy was found to be independent of stress with a value close to the one found in the cold-worked material.