Effect of Reinforcement on Micro Structural and Compressive Deformation Behavior on Closed Cell AA7075 Aluminium Foam

Abstract

The fabrication of aluminium AA7075 and AA7075/SiC composite foams employ the stir casting method, incorporating calcium carbonate (CaCO3) as a blowing agent at a concentration constituting 2.5wt. % of the alloy. Notably, no viscosity-enhancing component was included in the process. The compressive parameters, including the yield strength (σc), plateau stress (σpl) and energy absorption (Eab), of the foam materials were examined to investigate the influence of Silicon Carbide (SiC) on the microstructure, namely the cell size and cell wall thickness. The incorporation of Silicon Carbide particles (SiC) into the cell wall imparts enhanced hardness and strength. The findings indicate that the inclusion of SiC particles may enhance the mechanical properties like σc, σp and Eab, of composite foams. The porosity of the composite foam increases from 59.07% to 68.68% with the incorporation of SiC particles. The cell dimensions fluctuated between 1.12 and 1.45mm as the relative density of the AA7075/SiC composite foam decreased from 0.4 to 0.31.