Friction Stir Welding (FSW) was used to perform Bead on Plate (BOP) welds on 6061-T6511 aluminum extrusions. Using a DOE approach, tool rotation speed, clamp spacing, and clamping force were altered to ascertain their effects on distortion in the welded panels. Mechanical forces were monitored during the weld process. Both linear and out of plane distortion were measured on the welded extrusions. The Vickers hardness of the weld nugget was measured. The effect of each parameter on weld distortion was discovered and the mechanism of this link was suggested.

Articulated haulers are fundamental equipment to transport material. The load carrying structure on a hauler consists mainly of welded frames. During welding of the frames high residual stress will be introduced. These stresses may have a significant impact on the fatigue life of the frames. This is the reason for having good knowledge of the weld residual stresses. The finite element method was used to calculate the residual stress distributions in a butt weld and a T-join weld. Simulation of the welding process with thermal and mechanical analysis was prepared by means of welding GUI implemented in LS-PrePost. The welding simulation is a computer intensive operation with high CPU time. That is why it is important to investigate which process factors that have the largest impact on welding simulation results. The aim of this thesis is to investigate the correlation between designed models in FEA software with published results of weld residual stress measurements and conclude which parameters should be mainly taken into consideration.