Master thesis and internship[BR]- Master's thesis : Finite element modeling methodology of a tungsten inert gas weld on S355MC Steel[BR]- Integration Internship : CRM Group

Abstract

Welding is a widely used fastening process, but is nevertheless extremely complex. The merging of a non-conventional heat input and a complex material compose a multi-layered problem that has been studied since the XIX century. In this manuscript, a Tungsten Inert Gaz weld on S355MG steel has been investigated and reproduced using the LS-Dyna Software. This work lays the foundation for further research on the welding phenomenon so that, eventually, the residual stresses and deformation induced by the fastening of two steel parts can be predicted with a sufficient level of confidence. To this end, an experimental setup was developed, with the aim of reproducing it with a Finite element software. Two main variables of the problem were measured: the temperature and the displacement. Two separate experiments were necessary to retrieve this data, who was then compared to the output of the Finite Element model. Temperature similarity was reached for the data set of the first experiment by neglecting the convection. Applying the same adjustments to the parameters given by the second experiment did not induce temperature similarity however. The displacement of the plates were not reproduced as well. The neglection of convection has thus to be discarded and leads on new parameter adaptation are explored.