Finite element analysis of welding processes using solid-shell elements

Abstract

Welding is a very complex process as a typical multi-physics process that involves phase transformation, heat transfer and deformations. Finite element analysis of welding is conducted for the prediction of residual deformations and stresses, which are often in the three-dimensional nature. Particularly, welding processes of plate structures involve inherently three-dimensional residual stresses and deformations, which are hardly modeled using the classical shell elements that oversimplify the through-thickness stress and deformation of shells. On the other hand, the use of three-dimensional solid elements for these processes is far from being suitable as it is too costly to model plate or shell structures with three-dimensional solid elements. The purpose of the present study is to develop an efficient solid-shell finite element that is appropriate for modeling welding processes of plate or shell structures. The existing modification of the hexahedron element based on Taylor series expansion is explored again, and some modification is made for handling the stiff transverse shear behavior. After finite element implementation based on hyperelastic formulation, several examples are demonstrated. The numerical results show that the present solid-shell finite element is extremely efficient for analyzing welding processes of plate or shell structures, particularly when these structures are welded while being subjected to bending moments.