Melting of Aluminium

The melting point of pure aluminium is 658 ºC. The most common manufacturing processes in the production of aluminium castings are sand casting, mold casting and die casting. The melting may take place by means of a fuel fired or electrically heated furnace. The raw materials for the production of remelted aluminium consists of various types of scrap, and cutting, punching, milling and turnings obtained during manufacture of virgin aluminium objects, and worn aluminium parts such as recycled cans, old car parts and appliances.

In modern remelting plants the aluminium scrap is pretreated by different methods and then melted in special furnaces. The melt is normally treated with large quantities of flux and sometimes chlorine gas. This results in a high quality product.

Most of the remelted metal is used in foundries and is then alloyed with copper and/or silicon. Delivery is in the form of ingots or liquid metal in well insulated ladles.

Ref. Gränges Aluminium, Aluminiumlära