Mechanical Properties of Welded by Friction Stir Welding Aluminium Alloy AA 5754

Abstract

Friction stir welding is one of the most original methods for welding devised in recent years. As this welding method possesses advantages compared to conventional fusing welding methods, scientific research on its features and improvement is increasing. The advances in the knowledge of the process of friction stir welding allow its increasing application in different areas, such as aircraft and automotive industries, railway transport, nuclear industries etc. During friction stir welding the joined parts are in a solid state. This welding method is mainly used for joining aluminium and its alloys.The stirring and mixing of the material and the temperature during friction stir welding are the main factors that determine the possibility of obtaining weldments with precise mechanical properties.The present study aims to research the influence of the pin`s configuration on different quality aspects of the weldments at chosen parameters of the welding mode. To achieve this, pins with different geometry and coatings were used. Results that demonstrate the influence of the pin`s geometry and the process parameters on the temperature, structure, and mechanical properties of joined by friction stir welding weldments of aluminium alloy AA 5754 4 mm thick are presented. The influence of the pin`s geometry on defect formation during welding was determined.