Modeling and Simulation Based Analysis of the Matter Flow During Friction Stir Welding Process

Abstract

Friction Stir Welding (FSW) is a recent assembly process which has been developed at the British Welding Institute (TWI) at the beginning of the 90's. This welding process has gone a rapid development and an increasing success. Many remarkable industrial applications achieved mainly in spatial, aeronautical, automobile, railways, marine and naval industries.... The translation and the rotation of the tool during the FSW process generate the flow and plastic deformation of the material which had been often differently interpreted in contradictory manner. In this paper, an analytical model is proposed to describe the flow of matter in the vicinity of the FSW tool pin during the welding process. Analytical solutions are elaborated on the basis of conventional fluid mechanics theory which is used to solve the associated equation to the mentioned problem based on the Laurent's series (called also Laurent's development). The knowledge of the material flow around the tool pin can lead to a better understanding of the metallurgical phenomena which have a significant effect on the mechanical properties of the welded joint and allows a better description of the speed fields which is worth full for the thermal modelisation since the great part of the thermal power is generated by auto-heating energy. The results obtained on the effect of the speeds on the material flow are in good accordance with the experimental results found in the literature. The study highlights and gives a better understanding of the material flow phenomenon during the Friction Stir Welding process.