Investigation of microstructural and wear properties of stir cast and friction stir processed AA 2014-based metal matrix composites

Abstract

ABSTRACT Due to the major applications in various industries, the global demand for Metal Matrix Composites (MMC) is increasing. The characteristics of manufactured composites highly depend upon the manufacturing method. The present research article showcases the manufacturing of three different compositions, namely AA 2014 + 5 wt.% SiC, AA 2014 + 10 wt.% SiC and AA 2014 + 15 wt.% SiC. A stir casting process has been implemented to manufacture these composites. While implementing the casting process one cannot get rid of the defects that are generated during the solidification. Thus, to avoid these defects in as-cast composites, friction stir processing (FSP) has been performed. FSP avoids casting defects and further enhances the distribution of reinforcement particles. The considered combinations of rotational speed and transverse speed are as follows (i) 270 rpm and 78 mm/min (E1 condition) and (ii) 190 rpm and 50 mm/min (E2 condition). Furthermore, the article compares the microstructure, microhardness and tribological properties of the as-received AA 2014 alloy, as-cast and processed composites. Irrespective of the FSP condition, AA 2014 + 10% SiC composites revealed the highest wear resistance among all the variety of specimens considered for the wear test.