Analysis of Sheet Metal Formability Studies of Friction Stir Processed Mg AZ31B Alloy using Response Surface Methodology

Abstract

Weight reduction of the automotive components is one of the major goals of engineering design and manufacturing so that materials, energy, and costs are saved and environmental damage is reduced by reducing the overall weight of the vehicle. Magnesium alloys provide the solution for weight reduction as they have a high strength to weight ratio and can contribute to the overall weight reduction of the vehicle. Over the past few years, many researchers have tried to shape these alloys using various forming techniques. These studies have indicated that it is difficult to improve the room temperature formability of these alloys without deteriorating its strength. In this present work, a severe plastic deformation technique namely friction stir processing (FSP), which provides severe plastic deformation along with higher strain rates, than the conventional methods like ECAP, HPT, ARB etc, has been utilized for microstructural modification of the magnesium AZ31B alloy, thereby improving mechanical properties and formability of the material. In this present work, sheets of Mg alloys were processed under various combinations of rotational speed, traverse speed and tool tilt angle as per the selected experimental design. The total elongation of the friction stir processed sheets were measured from the tensile tests and the results were modelled using Response Surface Methodology's (RSM) Box Behnhen Design and the response equation and response plots were drawn and various conclusions were made.