Investigations into an efficient computational tool for the simulation of friction stir welding of thermoplastic polymers

Abstract. Welding is one of the major categories of manufacturing technologies, serving for the joining purposes for a wide variety of workpieces with different shapes and materials. Due to the intense thermo-mechanical phenomena occurring during welding, affecting the workpieces both in the macroscopic and the microscopic level, the choice of the processing conditions is not a trivial procedure in any case. Despite the availability of practical suggestions for the welding of large variety of materials, the increase of the use of some types of materials and the use of novel materials in the industrial applications, the detailed study of the phenomena occurring during welding is necessary. Although a considerable amount of numerical studies on the simulation of friction stir processing already exists, it is necessary to evaluate the validity of low cost and robust models in order to obtain fast but reliable results in the case of process optimization or preliminary studies. In this work, a low cost FE model is implemented and validated against experimental data regarding the prediction of temperature field during the friction stir welding of thermoplastic polymers. The findings of this work showed that although the low cost model contains several simplifications that restrict its accuracy, it was able to predict the temperature field and some heat transfer related quantities reasonably, indicating a potential for further improvement in order to adapt to a wide range of materials and operating conditions.