Patent ID: 7048815

Claim:
A method for fabricating an aluminum alloy composition comprising: selecting an aluminum alloy composition; melting said aluminum alloy composition; casting said aluminum alloy, said casting characterized by a cooling rate of at least about 40° C./sec; annealing said cast aluminum alloy at a first annealing temperature at a temperature between about 250° C. to about 370° C. without prior homogenization of said cast aluminum alloy, so as to precipitate non-soluble scandium particles from said alloy compositions in the form of coherent Al 3 Sc particles in order to inhibit grain growth and recrystallization during annealing at a second annealing temperature; annealing said aluminum alloy at said second annealing temperature between about 430° to about 515° C. after annealing at said first annealing temperature; quenching said aluminum alloy after annealing said aluminum alloy at said second annealing temperature; and aging said annealed aluminum alloy, wherein said aluminum alloy composition is selected from a composition comprising between about 6.0% to about 12.0% by wt. of zinc, between about 2.0% to about 3.5% by wt. of magnesium, between about 0.5% to about 3.0% by wt. of copper, between about 0.10% to about 0.45% by wt. of manganese, between about 0.05% to about 0.20% by wt. of zirconium, between about 0.1% to about 0.5% by wt. of scandium between about 0.02% to about 0.35% by wt. of iron, between about 0.02% to about 2.0% by wt. of silicon between about 0.00% to about 0.05% by wt. of titanium between about 0.00% to about 0.25% by wt. of chromium between about 0.00% to about 0.05% by wt. of vanadium between about 0.00% to about 0.05% by wt. of hafflium between about 0.00% to about 0.20% by wt. of cerium between about 0.00% to about 0.20% by wt. of silver, and aluminum.