Hybrid composites produced by anodizing and accumulative roll bonding (ARB) processes

In this study, microstructure and mechanical properties of Al/1.6 vol% Al2O3/1.5 vol% B4C hybrid composite produced by anodizing and accumulative roll bonding (ARB) processes were investigated. Microstructural observations and fractography were performed by scanning electron microscopy (SEM). Also, the mechanical properties were investigated by tensile and microhardness tests. It was found that with increasing the number of ARB cycles, a better distribution of Al2O3 and B4C particles was obtained in the aluminum matrix. The hybrid composite after the tenth cycle demonstrated a uniform distribution and a strong bonding between the particles and the matrix without any porosity. Furthermore, ARB-processed monolithic and also, the hybrid composite showed much higher tensile strength than the annealed aluminum sample. In addition, elongation of ARB-processed monolithic and also, the hybrid composite was decreased in the first step and then increased as a result of increasing the number of cycles. Moreover, the ARB-processed monolithic and the hybrid composite exhibited higher hardness than the annealed aluminum. Finally, it was realized that the monolithic and hybrid composite samples had a shear ductile fracture, dimples and shear zones. However, the number of sources in the void nucleation of the composite was more than that of the monolithic sample.