Abstract
In recent years, there has been an increasing demand for aluminum foams for aerospace, automotive and marine applications. To provide a fundamental basis for advanced engineering developments, understanding the corrosion behavior of this novel class of porous material is vital. However, determining accurate mass loss for corrosion tests of these materials is challenging due to the difficulty of removing corrosion products on a large and inhomogeneous surface. In this project, nitric acid immersion was evaluated as a chemical cleaning technique to remove corrosion products from aluminum 6101 foams (UNS A96101) with different pore sizes and surface areas and were subjected to exposure in simulated seawater (3.5 wt% NaCl solution) environments. The cleaning protocol was performed by immersing as-received and post-corroded UNS A96101 foam alloys in 68-70 wt% nitric acid solution at room temperature for various times. The same protocol was performed on the UNS A96101 bulk alloys and the results were compared to their foam counterparts. Scanning electron microscopy (SEM) was used to characterize the corroded surfaces and qualitatively determine the optimal cleaning duration.
