Duralloy is a super-alloy found in almost all editions of Gamma World, as well as Metamorphosis Alpha.
Duralloy can be found in plates of uniformed sizes, usually with pre-cut holes. Such plates can be used to make a superior class of shield. They also be found in special containment drums that maintains the material in a molten state by a magnetic field. Once the seal is broken, the liquid metal must be used quickly (about a minute) before it cools down and becomes permanently solid. The cool down is rapid, and absorbs background heat.
In the past, force-fields were used to create a mold for the liquid-Duralloy to be pumped into it, shaping into the mold once the metal cooled.
Although the material can take a lot of punishment, its role as armor was seen as secondary compared to force-field technology - it was the last degree of defense when a force-screen is knocked-down. The true strength the ancient people found in Duralloy was its ability to erect super-structures, like massive domed-cities, sky-bridges, and even giant space colonies. During the conflicts of the Shadow Years, Duralloy was used to make war-machines and military hardware. Despite their great strength, countless super-structures and war-machines were destroyed in the conflict.