Microstructural and corrosion study of aluminum foams obtained by space holder process using low-cost removable preforms

The space holder process (SHP) is a useful and common technique to obtain metal foams. However, an important question remains unsolved: Would the quality of the salt affect the properties of the aluminum foam obtained? In this paper, removable preforms of two types of salt (refined and unrefined) were infiltrated with A356 aluminum alloy to obtain metal foams with different pore sizes. The interaction preform-metal was studied from analyzing the morphological structure of the foams, the metal microstructure, and the corrosion resistance of the Al356 alloy. It was observed that, although the two types of salt exhibited some differences, they did not show variations in relation to the porous structure and metal microstructure in the aluminum foams obtained. Additionally, the electrochemical analyses did not show significant effects on the corrosion behavior of aluminum foams caused by the interaction with the salt preforms.