Influence of ARB technique on the microstructural, mechanical and fracture properties of the multilayered Al1050/Al5052 composite reinforced by SiC particles

Abstract

In this paper, Al1050/Al5052/SiC composite was manufactured via accumulative roll bonding (ARB) technique, and the fracture toughness for the different passes was experimentally investigated. The microstructure, mechanical properties, and fracture behavior were determined through Optical Microscopy (OM), Scanning Electron Microscopy (SEM), tensile test, microhardness, and plane stress fracture toughness. The results of OM showed that local necking and failure of Al5052 reinforcement layers happened at the 1st pass and after that by raising the exerted strain the shape of the layers varied from the lamellar to particle form, and finally, Al1050/Al5052/SiC composite was provided via perfect dispersion of layers and particles reinforcements. The microhardness variations were ascending for both Al layers in terms of ARB cycles, and this trend was observed for UTS variations except for the third and fourth passes so that in the both passes the strength was downtrend. Finally, the best UTS and elongation values were obtained on the last pass. The results of SEM demonstrated that by raising the exerted strain, the kind of fracture mechanism varied to shear ductile from ductile. From zero pass (primary sandwich) to the second pass, the rate of changing in fracture toughness was ascending and then drastically reduced. Also, maximum and minimum values are achieved at second and third ARB cycles respectively. Due to the higher variation in the strength compared to elongation, as in previous researches, the trend of toughness was similar to that of strength, with this difference that the presence of ceramic particles at the interfaces was causing the brittleness in the composite.