ductilemetal

A ductile metal is a metal that can undergo substantial plastic deformation before fracturing under tensile or other loading. Ductility is typically measured by the elongation and reduction of area at fracture in standardized tests, such as tensile tests.

The ability to deform plastically stems from dislocation motion on crystallographic slip systems, which allows atoms to rearrange without immediate fracture. Materials with many slip systems, especially face-centered cubic metals, tend to be highly ductile, whereas some body-centered cubic metals may be less ductile at room temperature unless heated.

Common ductile metals include copper, aluminum, gold, silver, nickel, and austenitic stainless steels. Titanium and magnesium alloys can also be quite ductile depending on alloy chemistry and processing. Temperature, strain rate, and grain size strongly influence ductility; higher temperatures and finer grains can enhance plastic deformation before failure.

Ductile metals are preferred for forming operations such as drawing, rolling, and extrusion, where large deformations are required to shape a part. They also provide high energy absorption and toughness, contributing to use in structural components and safety-critical applications. There is typically a trade-off between ductility and strength, which can be tuned by heat treatment and alloying.

Ductility is contrasted with brittleness, where materials fracture with little or no plastic deformation. Some metals exhibit a ductile-to-brittle transition with temperature or loading conditions, so ductility is not fixed and depends on environment and processing.