Evaluation of Mechanical Behaviour of Friction Stir Welded Joints

Abstract

Friction stir welding is a solid state joining technique that is widely being used for joining aluminium alloys in industries, especially the shipbuilding, aerospace, mass transportation and automotive and many other applications of commercial importance. This process is considered as a “green technology” due to its energy efficiency, environmental friendliness, and versatility. Friction stir welding was carried out using a vertical milling machine on Aluminium 6063 alloy. The tool material and geometry were carefully chosen and prepared using lathe machine. Important process parameters that control the quality of the weld are rotation speed (rpm), traverse speed (mm/min), tool depth (mm) and tool tilt angle and these process parameters were optimized to obtain defect free welded joints. It is observed that, during the friction stir welding, extensive deformation takes place at the nugget zone and the evolved microstructure that strongly affects the mechanical properties of the joint. The aim of present study is to understand the mechanical properties and micro structural changes of the friction stir welded joints.