The influence of fatigue stress on the creep behaviour of metals

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

A theoretical model, which considers the nature of crystallographic slip in the grain and the heterogeneous stress distribution arised from grain orientations, is proposed for the calculation of cyclic creep behavior of metals. Here the hardening mechanisms which cause the creep rate of slip systems to decrease are generally classified into two broad groups: isotropic, and directional or kinematic; under cyclic deformation the influence of isotropic mechanisms was found to gradually give way to the kinematic mechanisms. An implication of this transition is a softer substructure under cyclic loading, and with the heterogeneous stress field it can also assist the backward dislocation motion, or strain recovery, upon unloading. Indeed, backward dislocation motion and the transition of hardening mechanisms were found to be the major driving forces for cyclic creep acceleration. If this transition takes place too slowly cyclic creep retardation may result. This micromechanical model was applied to study the cyclic creep behavior of a 99.999% pure aluminum. The results, including the effect of fractional unloading, were seen to be in accord with the experimental data.

Original languageEnglish (US)
Pages (from-to)207-212
Number of pages6
JournalActa Metallurgica
Volume31
Issue number1
DOIs
StatePublished - Jan 1983

All Science Journal Classification (ASJC) codes

  • Engineering(all)

Fingerprint Dive into the research topics of 'The influence of fatigue stress on the creep behaviour of metals'. Together they form a unique fingerprint.

Cite this