Aluminum Casting: Process Description

Tapping Molten Aluminum for casting from a tilting barrel furnace.
Courtesy of Can Eng Manufacturing, Ltd.

Casting
Heattreating
Mining/Primary Processing
Recycle/Scrap Melting
Aluminum Casting
Aluminum Smelting
Anode Baking
Bauxite Mining
Bauxite Refining
Extrusion
Forging
Heat Treating
Molten Handling
Rolling

Casting consists of pouring molten aluminum into molds. Once in the mold, the aluminum solidifies into the shape defined by the mold. Three different casting methods are used: sand casting, permanent mold casting, and die casting. Molten aluminum is derived from three different sources: ingots from a primary aluminum producer, molten aluminum directly from a smelting plant, or partially processed recycled aluminum scrap.

Glossary

Sand Casting

Sand casting is the most versatile method and the most economical for producing small quantities. Almost any shape mold can be produced from fine sand and binder mixture.

Permanent Mold Casting

Permanent mold casting uses steel or other metal molds to shape the molten aluminum. Molten aluminum is forced into the mold under gravity or with the aid of a vacuum. Permanent mold castings are stronger than sand castings and less expensive for large production quantities.

Die Casting

Die casting is used for producing accurate components which require little subsequent machining. The molten aluminum is forced under high pressure into steel molds or dies.