Place the aluminum in an electric resistance furnace. Place cast-iron chills (molds) perpendicular to the direction in which the melted aluminum will flow.
Melt the aluminum by increasing the furnace temperature to 740 degrees Celsius. Using a rotary gas lance, control hydrogen levels in the melting aluminum by bubbling argon gas through the furnace.
Remove the molds from the furnace. Drop the molds in boiling water, allowing aluminum to quench (rapidly cool). Alternatively, place the molds in a glycol solution or in air being moved by high-velocity fans.
Age quenched aluminum depending on the level of ductility (ability to be stretched) that you need. You can age aluminum simply by leaving it sitting out on the lab bench at room temperature thereby allowing fine precipitates to form. You can also accelerate aging by heating samples to intermediate temperatures.