ADDA ATTOU, AhmedGOUMID, Alaa EddineSERIER, MOHAMED2024-09-082024-09-082024http://dspace.univ-temouchent.edu.dz/handle/123456789/4988FSW, or friction stir welding, is a solid-state welding process. This innovative technique does not require the complete fusion of materials. It uses a special tool which, thanks to a rotating pin, brings the parts to be assembled to a pasty state. Although FSW is primarily used for aluminum alloys, it can also be applied to other materials. Among its advantages are the reduction of weld defects, the preservation of material properties and the ability to weld dissimilar materials. This thesis aims to understand the thermal and mechanical aspects involved in this innovative welding process. When studying friction stir welding (FSW), the use of experimental designs is essential to evaluate weld quality. This study uses heat transfer modeling and numerical simulation to understand the FSW process. It aims to develop and apply heat transfer models to generate three major interfaces that produce heat flow between the tool and the material. Conduct practical FSW experiments to validate the numerical results and ensure the applicability of the study in real-world conditions. Experiments were carried out by varying two parameters. To measure the temperature in the welding zone, these experiments were carried out on two HDPE plates. The study examines how variations in welding speed and rotational speed affect the thermal and mechanical aspects of FSW.frThesis