Abstract
The paper concerns with the mechanical modelling and the finite element simulation of the fracture failure in mode I of linear joints of aluminum friction stir weldings. The problem is analyzed employing a bulk finite strain-hardening plasticity model able to characterize the spatial diffuse plastic strains that initially develop in the neighbouring extended zones of the welding line. Moreover, the decohesion process is described by a zero thickness interface model which is spatially inserted along the line of the welding.