toughness

mechanics

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July 14, 2026

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Toughness is a material property that describes its ability to withstand stress and deformation without fracturing. It's a measure of the energy a material can absorb before it breaks.1

Materials can fail due to excessive stress or deformation. Designers select materials that can handle anticipated stresses. Mechanical property tests help determine suitable materials.

Ductility is a material's capacity to deform permanently under stress. Ductile materials, like most steels, can accommodate stress concentrations, unlike brittle materials such as glass, which fracture easily.1

Toughness can be expressed as strain, reduction in area, or the energy required for permanent deformation. Advanced structural ceramics are being developed with enhanced mechanical properties, including toughness, to perform under demanding conditions where traditional materials might fail. Methods like reinforcing microstructures, microcracking, and transformation toughening are used to improve ceramic toughness.12

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metallurgy
Testing mechanical properties
…a measure of the solid’s toughness. In a hard, brittle material, toughness is low, while in a strong, ductile metal it is high. A common test of toughness is the Charpy test, which employs a small bar of a metal with a V-shaped groove cut on one side. A large…
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…a measure of the solid’s toughness. In a hard, brittle material, toughness is low, while in a strong, ductile metal it is high. A common test of toughness is the Charpy test, which employs a small bar of a metal with a V-shaped groove cut on one side. A large…
Read More

plastic
Properties
Another important property is toughness, which is the energy absorbed by a polymer before failure—often as the result of a sudden impact. Repeated applications of stress well below the tensile strength of a plastic may result in fatigue failure.
Read More
Another important property is toughness, which is the energy absorbed by a polymer before failure—often as the result of a sudden impact. Repeated applications of stress well below the tensile strength of a plastic may result in fatigue failure.
Read More