FINITE ELEMENT SIMULATION OF HEAT TRANSFER IN FRICTION STIR WELDING OF AL ۷۰۵۰

Friction welding is widely used in various industries. In friction welding, heat is generated by conversion of mechanical energy into thermal energy at the interface the work pieces during pin rotation under pressure. A three-dimensional thermo mechanical simulation of friction stir welding (FSW) processes is carried out for Aluminium Alloys of ۶۰۶۱and ۷۰۵۰ where the simulation results are compared directly with the measured temperature histories during FSW after process. The objective of the present work is to study and predict the heat transient generated in alloy aluminium plate welded by FSW method. A three dimensional model was developed by LS-Dyna software and heat cycles have been proposed during the welding of aluminium alloys ۶۰۶۱ and ۷۰۵۰. In this research, the simulations were carried out with linear velocity in the range of ۱۴۰ to ۲۲۵ mm/min and pin rotational speeds of ۳۹۰ and ۵۰۰ rpm. Increase in pin rotational speed, from ۳۹۰ to ۵۰۰ rpm, resulted in greater temperatures which translated to rise of recorded temperature of top and bottom of the specimens. This is in turn to a wider HAZ. In addition, it was observed that raising the linear velocity had an opposite effect. Finally, results of experimental and numerical data were correlated and validated

Keywords:

Friction stir welding (FSW) , Aluminium alloy ۶۰۶۱ and ۷۰۵۰ , Finite elements method.