Characteristics of Al6061-SiC-Al2O3 Surface Hybrid Composites Fabricated by Friction Stir Processing

Abstract

Friction stir processing (FSP) has successfully evolved as an alternative technique of fabricating metal matrix composites. (MMC). FSP has been used positively to produce surface composite that offer good surface properties such as higher hardness and wear resistance, also help in the development of finer-grain structure during thermomechanical processing of the material. This work aims to fabricate a surface composite upon the AA6061-T6 Al alloy via FSP. The effect of SiC and/or Al2O3 particles on microstructure, microhardness, and wear behavior of the surface composite was investigated. Many drilled holes were made to incorporate the ceramic particles within the matrix at the optimal friction stir processing circumstances, The optimal parameters of (FSP) were (32 mm ̸min), (1250 rpm), and (2) passes in a similar track.. It was obtained that the maximum microhardness being in the stir zone center of FSP of the base alloy and all composites. The results of XRD and EDX mapping confirmed the incorporation of SiC and Al2O3 particles within the surface of Al alloy using FSP which will improve the surface properties. The improvement in microhardness was (89.3%) in the case of FSP composite sample reinforced with hybrid addition (SiC+Al2O3) particles in comparison to FSP unreinforced base alloy (75 HV). It was showed that the wear resistance of the FSP composite sample reinforced with hybrid addition of (Al2O3 and SiC ) particles was slightly better than that of the FSP composite sample reinforced with single Al2O3 or SiC particles and base Al alloy.