Formulation of the butt joints of aluminum composite using friction stir welding and study of their mechanical properties

Abstract

In this study, experiments were performed on the vertical milling machine to formulate butt joints of aluminum matrix composites (AMCs) having 5 vol% SiC as particulate using friction stir welding technique. Joints prepared were tested to find their mechanical properties using different testing methods. The butt joints were formed from the plates of Al-SiC composite plates. Alloy steel tool hardened at a temperature of 850°C was used to obtain welded joints. Three different pin shapes were used to do welding at three different tool rotations ranging from 600-1200 rpm based upon pilot experimentation. Tensile tests were done on the universal testing machine to find yield strength and ultimate strength. Hardness of the welded joint is also calculated using the vickers hardness test. The joints prepared using non tapered pin shape had better tensile properties as compared to other pin shapes. Good mechanical properties were obtained at 1200 rpm tool rotation. The hardness of the welded joint also got improved when welded at 1200 rpm using non tapered pin shape. The microstructure results also verified that refinement of grains takes place at higher tool rotations which improved mechanical properties.