Properties and corrosion behavior of Al based nanocomposite foams produced by the sintering-dissolution process

The properties of Al based nanocomposite metal foams and their corrosion behaviors were investigated in this study. For this, the composite metal foams with different relative densities (porosity) reinforced with alumina nanoparticles were prepared using a powder metallurgy- based sintering-dissolution process (SDP) and NaCl particles were used as space holders. Then, the effect of nanoparticle reinforcement and different amounts of NaCl space holders (corresponding porosity) on the microstructure, morphology, density, hardness, and electrochemical specifications of the samples were investigated. It was found that as the relative density increased from 60% to 70%, the wall thickness increased from about 200 to 300 mu m, which led to a decrease in pore size. Also, the addition of nanoparticle reinforcement and the increased relative density result in increasing metal foam hardness. Moreover, electrochemical test results indicated that increasing the Al2O3 content reduced the corrosion rate, but increasing the porosity enhanced it.