Influence of Traverse Speed on Microstructure and Mechanical Properties of AA6082-TiC Surface Composite Fabricated by Friction Stir Processing

Abstract

Friction stir processing (FSP) has evolved as a novel solid state technique, for refinement of microstructure, enhancement of mechanical properties and fabrication of aluminium matrix composites (AMCs). In this work, AA6082/TiC surface AMC was produced by FSP technique and the effect of traverse speed on microstructure and mechanical properties were investigated. The traverse speed was varied from 40mm/min. to 80mm/min. in steps of 20mm/min. The rest of the process parameters such as groove width, tool rotational speed and axial force were kept constant. Micrographs of the AA6082/TiC AMCs were obtained using optical microscope and scanning electron microscope. Microhardness and wear behaviour of the surface composites were analysed. Results revealed that the traverse speed significantly influenced the area of surface composites, dispersion of TiC, grain size of matrix, microhardness, and wear rate of the AA6082/TiC AMCs. The traverse speed was inversely proportional to the area of surface composites. The homogenous distribution of TiC particles was attained with lower traverse speed, whereas poor distribution of TiC particles was influenced by the higher traverse speed. Also increase in the traverse speed of the surface composite enhanced microhardness and reduced the wear rate when compared with lower traverse speed.