3D uncoupled thermo-mechanical analysis of friction stir welding (FSW) of aluminum alloy AA1100 was carried out using FEM. The heat generated in the FSW process is applied via DFLUX subroutine of ABAQUS. Simulations with different process parameters such as welding speed and rotational speed were performed for the estimation of temperature generated during the FSW process. Thermal analysis’s output is applied as thermal loads during mechanical analysis. Subsequently, residual stress developed during the FSW process was found out. Residual stresses were measured along the selected path, which included node to node stress variations in longitudinal directions. Maximum temperature appears to occur at the center of the weld pool and decreases away from the weld line towards the base metal. The numerical and experimental results were successfully validated with error in the range of 0.5 - 6%. Then, a semi-analytical equation for temperature distribution considering moving point heat source is proposed to carry out single objective unconstrained optimization of process parameters (welding speed and rotational speed). Finally, optimization was carried out to estimate the maximum temperature generated during the FSW process using a genetic algorithm in MATLAB.
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