Uniform and graded chemical milling of aluminum foams

Commercial open-cell aluminum alloy foams are subjected to chemical dissolution to reduce their density. Dissolution rates are measured for various pH, temperature and alloy heat-treatment conditions, and the resulting foam structures and surface conditions are evaluated by microscopy and X-ray microcomputed tomography to identify conditions which minimize corrosive damage. The effect of uniform dissolution on foam compressive mechanical properties is interpreted in terms of these observations. A method for production of density-graded foam samples from uniform-density precursors is also demonstrated.