Influence of tool geometry on morphology and mechanical properties of friction stir welded dissimilar joints: A review

Abstract

In this paper, the effect of tool geometry and its parameter on properties of dissimilar materials weld joint has been studied. Joining of dissimilar alloys (such as Al and Mg-alloy) are abundantly used in aeronautical, automobile, and marine industries because of its outstanding characteristics such as low weight, high strength, good corrosive resistance, and cheap cost. The fusion welding techniques were not suitable for the joining of low melting point materials, due to the defects formed such as porosity, voids, and cracks. To reduce these problems, researchers paid attention towards the solid-state technique for welding such as Friction stir welding apart from the fusion welding. Tool geometry and its parameters play a crucial role in the fabrication of good weld joints with better morphological and mechanical properties. Hence the design of FSW tool is very essential. During FSW process, the plastic deformation of materials depends on the tool size; heat generation depends on the shoulder size; the grain size and morphology depends on the heat generated at the weld joint. The objective of this review is to discuss the different types of tool geometry and their effect on morphological and mechanical properties to achieve a sound weld joint.