Method for manufacturing environmentally conscious foamed aluminum materials

Abstract

A process for making high-quality foamed aluminum articles is disclosed. This process comprises the step of: (a) placing a raw aluminum feedstock into a mold, the raw aluminum feed stock contains at least 50 wt % spent (i.e., recycled) aluminum and does not contain any extraneous viscosity enhancing agent such as metallic calcuim or magnesium; (b) heating the mold so as to melt the raw aluminum feedstock to form a liquid aluminum mass; (c) stirring the liquid aluminum mass in open air to increase its viscosity by a factor of at least about 1.3 to 1.8; (d) adding a foaming agent into the liquid aluminum mass; (e) continuing stirring the liquid aluminum mass containing the foaming agent so as to generate and uniformly distribute gas bubbles inside said liquid aluminum mass; and (f) cooling and solidifying the liquid aluminum mass to room temperature so as to form the foamed aluminum article. In a preferred embodiment, recycled foamed aluminum materials are used as the raw aluminum feedstock. The foamed aluminum article has a porosity of at least 80%, a specificity density of no greater than 0.45, and an average pore size between 3 and 6 min. Because the process is self-thickening, and no extraneous thickeners such as calcium metal are needed, great economic benefits can be obtained without adversely affecting the quality of the final product.

Dependencies are inferred from the claim text.