Fatigue life prediction in AlMgSil lap joint weldments

The fatigue behaviour of an AlMgSil alloy lap welded joint and the improvem ent in fatigue strength due to post-weld heat treatment were investigated. Two series of fatigue tests were performed: one in as-welded specimens and another in heat-treated specimens. The prediction of crack initiation life under a plane strain condition was made based on the local strain approach using Morrow's modified equation. The local inelastic stresses and strains at the weld toe were calculated for the heat-treated specimens using three methods: Neuber, Glinka and finite element analysis. The accuracy of the di fferent methods were evaluated and discussed. (C) 2000 Elsevier Science Ltd . All rights reserved.