Finite element modeling for maximum temperature in friction stir welding and its validation

Friction stir welding is a relatively new joining process, which involves the joining of metals without fusion or filler materials. The amount of the heat conducted into the workpiece dictates a successful process which is defined by the quality, shape, and microstructure of the processed zone, as well as the residual stress and the distortion of the workpiece. The amount of the heat gone to the tool dictates the life of the tool and the capability of the tool to produce a good-processed zone. Hence, understanding the heat transfer aspect of the friction stir welding is extremely important, not only for the science but also for improving the process. Many research works were carried out to simulate the friction stir welding using various software to determine the temperature distribution for a given set of conditions in weldments. Very few attempted to determine the maximum temperature by varying the input parameters using ANSYS. The objective of this research is to develop a finite element simulation with improved capability to predict temperature evolution in stainless steel. The simulation model is tested with existing experimental results obtained by Zau et al. on 304 L stainless steel. The results of the simulation are in good agreement with that of experimental results. The peak temperature obtained was 1,056.853A degrees C, which was much less than the melting point of 304 L steel (1,450A degrees C). Error analysis is done between theoretical values for 304 L steel obtained from ANSYS and experimental values obtained by Zhu. Mean relative error is calculated between theoretical values for 304 L steel and experimental values.