Finite-element modeling of thermo-mechanical phenomena in friction stir welding of AISI 4340 steel

Most metallic alloys that are not easily joined by conventional fusion welding are usually joined by friction stir. on this basis, friction stir welding has seen a wide application in different industry. Friction stir welding is complex phenomena having connected physical phenomena. However, it is usually difficult to theoretically develop a system of governing equation to analyze friction stir welded joint, due to the three-dimensional nature and complex geometry. Also, the experimental techniques are often time consuming and costly. Meanwhile, numerical analysis has been introduced to overcome these problems. This study presents a straightforward perspective to friction stir welding (FSW) of AISI 4340 steel alloy numerical modeling and simulation. A three-dimensional heat transfer model for FSW was presented, the coordinate system was considered as a moving one, while the tool axis is fixed. Stationary convection-conduction was adopted to solve heat transfer problem. The Heat generated between the interface between the tool pin the work piece was simulated using model created in COMSOL Multiphysics software V 4.0.