Hydronalium

Hydronalium is a family of aluminium-magnesium alloys. It is an alloy predominantly of aluminium, with between 1%-12% of magnesium as the primary alloying ingredient. It also includes a secondary addition of manganese, usually between 0.4%-1%.

The Hydronalium alloys originated in Germany in the 1930s and are best known, at least by that name, in Eastern Europe. They were widely used for shipbuilding in Poland.