Ductility

From Freepedia

Ductility is the physical property of being capable of sustaining large plastic deformations without fracture (in metals, such as being drawn into a wire). It is characterized by the material flowing under shear stress.

A ductile material is any material that yields under shear stress (as opposed to brittle fracture, which yields under normal stress). Gold, copper, and aluminum are highly ductile metals.

Ductility is related to malleability.

In Earth Science, the brittle-ductile transition zone is a zone at an approximate depth of 10 km in the Earth, at which rock becomes less likely to fracture, and more likely to deform ductilly. In glacial ice this zone is at approximately 30 metres depth. It is not impossible for material above a brittle-ductile transition zone to deform ductilly, nor for material below to deform brittly. The zone exists because as depth increases, confining pressure increases, and brittle strength increases with confining pressure but ductile strength remains constant. The transition zone occurs at the point where brittle strength exceeds ductile strength.