The ZA alloys contain significantly more aluminium than the Zamak group of alloys with the numerical designation representing the approximate percentage of aluminium.
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The ZA alloys contain significantly more aluminium than the Zamak group of alloys with the numerical designation representing the approximate percentage of aluminium.

ZA-8 was originally developed as a permanent mold alloy having excellent finishing and plating characteristics. It is particularly suitable for decorative applications. Although this alloy does not exhibit quite as good casting characteristics as the other zinc alloys, it offers significantly improved strength, hardness and creep properties. In terms of mechanical performance, this alloy has the highest creep strength of any zinc alloy and the highest strength of any hot-chamber diecast zinc alloy. ZA-8 contains approximately 8.4% aluminium and is the only ZA alloy that can be hot-chamber diecast, an important consideration when selecting a material for a component.

Designers of structural components should be aware of the creep limitations of zinc alloys, which do not have a single value for elastic modulus or yield strength. Yield strength (allowable stress) under sustained loading is dependent on the allowable design strain (% elongation) over the required service life. Standard engineering formulae used for calculating cross-sections of elastic materials must therefore be used with some caution.