The property of a material that allows it to undergo some reasonable degree of irreversible permanent plastic deformation without fracturing. Ductility is the property of metals and alloys that allows them to be drawn or stretched. In general, metals and alloys with face-centered cubic structures exhibit the greatest ductility, followed by body-centered cubic structures, and then hexagonal close-packed structures. The order of ductility of certain materials is shown in Table D-3.