Article

Friction stir welding oof dissimilar aluminium alloys (6061 and 7075) by using computerized numerical control machine

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Abstract

Friction stir welding, a solid state joining technique, is widely being used for joining Al alloys for aerospace, marine automotive and many other applications of commercial importance. FSW trials were carried out using a computerized numerical control machine on (Al 6061 and 7075) alloy. The tool geometry was carefully chosen and fabricated to have a nearly flat welded interface (cylindrical and taper) pin profile.Important process parameters that control the quality of the weld are a) rotation speed (1600 and 1250rpm) b) traverse speed (120mm/min) and c) tool tilt angle 2° and these process parameters were optimized to obtain defect free welded joints. It is observed that, during the friction stir welding, extensive deformation is experienced at the nugget zone and the evolved microstructure strongly affects the mechanical properties of the joint. The present studies aimed to understand the micro structural changes and the associated mechanical properties during the FSW. The main aim of our project is to find the mechanical properties of friction stir welding of dissimilar aluminum alloys (6061 and 7075) by using CNC vertical milling machine. The limitations of FSW are reduced by intensive research and development. Its cost effectiveness and ability to weld dissimilar metals makes it a commonly used welding process in recent times.

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