ductility is the ability for a metal to be
Ductility Ductility is a measure of a material's ability to undergo significant plastic deformation before rupture, which may be expressed as percent elongation or percent area reduction from a tensile test. According to Shigley's Mechanical Engineering Design--10th Ed. [1] significant denotes about 5.0 percent elongation (Section 5.3, p. 233). See also Eq. 2-12, p. 50 for definitions of percent elongation and percent area reduction. Ductility is often characterized by the material's ability to be stretched into a wire.
Dividing line between metals and nonmetals The dividing line between metals and nonmetals can be found, in varying configurations, on some representations of the periodic table of the elements (see mini-example, right). Elements to the lower left of the line generally display increasing metallic behaviour; elements to the upper right display increasing nonmetallic behaviour. When presented as a regular stair-step, elements with the highest critical temperature for their groups (Li, Be, Al, Ge, Sb, Po) lie just below the line.[1]