Numerical analysis of the influence of material mismatching in the transition curve of welded joints

In this paper finite element simulations of mismatched welded joints at different temperatures have been performed in order to analyse the influence of temperature on their fracture behaviour and to obtain their transition curves. Cleavage is described by means of the Beremin micromechanical model. The ductile failure model is based on the so-called complete Gurson model. Both fracture mechanisms have been implemented in FORTRAN and introduced in ABAQUS by two user subroutines. The weld configuration significantly affects the stress and strain fields and different transition curves are obtained for the different configurations. The highest transition curve is obtained for the narrowest overmatched weld, being its transition temperature the lowest.