Effect of Friction Stir Welding Parameters on Impact Strength of the AZ31 Magnesium Alloy Joints

In this experimental work, a study was done to see the effect of Friction stir welding parameters on the impact strength of the welded joints of AZ31 magnesium alloy. The AZ31 magnesium alloy was taken in form of plates with a thickness of 6mm. The plates were welded usinga tool made up of alloy steel using three different pin profiles i.e. cylindrical, tapered and threaded. The joints were welded at a three different rotational speeds keeping feed rate constant.The Impact strength of the welded joints was evaluated using Charpy test. Joints fabricated at the rotational speed of 1200 rpm with threaded pin profile showed better impact strength than the joint welded with other pin profiles. It shows as the as the rotational speed increases, a temperature of the weld increases which improves the ductility of the material which in turn improves the impact strength. More the contact surface of the pin profile more will be the impact strength. Results obtained mechanically is also verified by obtaining microstructures of base material i.e. AZ31 and nugget region obtained at 1200 rpm using threaded tool for FSW process.