A continuum damage model for ductile fracture of weld heat affected zone

Abstract

In this paper, the ductile plastic damage behaviour of weld heat affected zone (HAZ) is studied by use of continuum damage mechanics (CDM). Based on a continuum damage variable, D, the effective stress concept and the thermodynamics, a general continuum damage model for Isotropie ductile fracture is derived from a new dissipation potential chosen by the author herein. A comparison between the damage model and experimental results is presented and a good agreement is found. The model is also used to analyse the ductile plastic damage evolution in thermally simulated welding coarse-grained HAZ of a low alloy steel. The effects of stress triaxiality on plastic damage evolution and on ductile fracture of the coarse-grained HAZ are discussed. © 1991.