Effect of Deformation and Ceramic Reinforcement on Work Hardening Behaviour of Hot Extruded 2124 Al-SiCp Metal Matrix Composites

Abstract

Work hardening behaviour of discontinuously reinforced metal matrix composites (MMCs) is a complex phenomenon as compared to monolithic materials and is still not explicitly understood. Under the present investigation, the effect of deformation and reinforcement content on work hardening behaviour of extruded 2124 Al/SiCp MMCs has been reported. These MMC extruded rods having 10%, 15% and 20% volume fraction of SiCp and extruded at 9:1, 36:1 and 56:1 extrusion ratios (ERs) were used. Work hardening rates were calculated from true stress-strain data obtained from tensile testing results of these MMCs. The variation in work hardening rates was correlated with the variation of SiCp content and deformation (i.e., ER). Fracture strains were estimated using a model and correlated with the experimentally measured values. Morphology of fractured surfaces was examined to elucidate the different microstructural features induced during testing and their correlation with elongation.