Magnesium based sand casting alloys are used for aerospace applications including helicopter gearboxes and jet engine components. Over the last 20 years, key development goals for new aerospace alloys have included better elevated temperature performance combined with good corrosion resistance. Currently, the alloy with the best property envelope in this field is Elektron WE43B (Mg-Y-Nd-HRE-Zr). The castability of this alloy is, however, affected by a tendency to oxidation in the molten state. This requires attention to foundry detail if best results are to be achieved. This can impact on cost.

Magnesium Elektron have developed a new Magnesium alloy, with significantly improved castability, whilst maintaining a corrosion resistance and mechanical property envelope close to that of Elektron WE43B. This new alloy, currently known as Elektron 21, is compared and contrasted with existing Magnesium casting alloys including WE43B, ZE41 and AZ91.