Key Features

• Measurement of Ductility: Ductility is measured mostly by elongation (the amount a material will stretch before breaking) and reduction of cross-sectional area measured during a tensile test. 
• Influences: Temperature, alloy composition and manufacturing processes all contribute in varying degrees to a material's ductility. Usually, as temperature increases ductility increases, while impurities or defects decrease it. 
• Common Use: Very ductile materials as copper, aluminum, and gold are used in almost all industries like construction, electrical wiring, and manufacturing. Due to easy shaping and processing, these materials are extensible.

Ductility becomes important in regard to the ability of these materials to remain functional after undergoing a deformation of some kind. Steel is an example of a ductile material that allows buildings and bridges to withstand the stresses and movements they experience in their lifetime without risk of worsened cracking. Ductile metals are useful in designs that require to be crashed and yet lightweight in most automotive and aerospace designs.