Ductility is the extent to which a material can sustain plastic deformation without rupture. Elongation and reduction of area are common indices of ductility. One method for determining ductility of metal wire is called a kink test, where a short section of wire is looped and drawn in tension to produce a kink. Relative ductility is indicated by the occurrence or non-occurrence of failure and extent to which kink may be opened up without failure.