MgAlZn

MgAlZn refers to a family of magnesium alloys in which aluminum and zinc are the primary alloying elements. This class is most commonly represented by the AZ-series, which are valued for a favorable combination of light weight, strength, and castability. The composition typically includes aluminum in roughly the 3–9 wt% range and zinc in about 0.5–1.5 wt%, with magnesium making up the balance. Variants such as AZ31, AZ63, and AZ91 differ mainly in aluminum content, affecting strength and creep resistance.

The microstructure of MgAlZn alloys features secondary phases such as Mg17Al12, which can contribute to precipitation hardening in some alloys. Many AZ-series alloys respond to heat treatment to adjust strength and ductility, though the degree of hardening varies among specific compositions. They generally offer good dimensional stability in casting and good machinability.

Manufacturing methods for MgAlZn alloys include die casting and other casting processes, as well as wrought forms produced by extrusion or rolling. Some alloys are suitable for heat treatment (solution treatment and aging) to attain higher strength, while others are used in as-cast condition for components requiring good stiffness and lightness.

Applications for MgAlZn alloys span automotive components (engine and transmission housings, valve covers), electronics enclosures, sports equipment, and lightweight structural parts. They benefit from low density and high strength, but corrosion resistance can be sensitive to environment. Protection strategies such as coatings or anodizing are commonly employed for outdoor or chloride-containing environments.