Nano-SiCp effects on the production, microstructural evolution and compressive properties of highly porous Al/CaCO3 foam fabricated via continual annealing and roll-bonding process

A recently developed experimental approach known as continual annealing and roll-bonding (CAR) process was utilized to produce a low-cost and highly porous aluminum nanocomposite foam by adding 0.75 CaCO3 and 0.75 nano-SiCp (wt%) to the structure of strips prior to foaming heat treatment in a preheated furnace at 750 °C. To investigate the effect of the nano-SiCp reinforcement, cell structure and microstructural features of the produced nanocomposite foams were examined during foaming process by scanning electron microscopy (SEM)/elemental distribution images and compared with the unreinforced foam specimens. Quasi-static compression test was performed on both types of foam specimens and deformation mechanism of the pores was investigated. The presence of nano-SiCp increased the compressive strength (66.5%) and energy absorption (57%) of the nanocomposite foam while it showed no significant influence on the cell structure. It was shown that extension of various deformation bands across the foam structure is the main deformation mechanism of pores during the compression test. Microstructural observations demonstrated that the role of nano-SiC differs in the Al foams produced by either carbonate or hydride foaming agents.