Aluminium master alloy is aluminium combined with a relatively high percentage of one or two other elements. It is a semi-finished product, and is manufactured for use as a raw material by the metals industry. Aluminium master alloys are used worldwide. Invariably they are found in plants where metal is melted, alloyed with various elements and then cast into shapes.

Reasons for using a master alloy instead of a pure metal can be economical, technical or both. Some elements show high losses - or poor yield - when added in pure form. Others will not dissolve at all at the furnace temperature prevailing in a cast house. A master alloy often provides the solution, as it dissolves much quicker at lower temperatures, saving valuable energy and production time.

Aluminium master alloys are produced in various shapes. Examples are: Ingot, waffle plate, rod in coils, etc.