ultimate tensile stress

mechanics

Also known as: UTS

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Last updated

July 14, 2026

Quick Summary

Ultimate tensile stress (UTS) is the maximum load a material can withstand when being stretched before it fractures, divided by its original cross-sectional area. This measurement is typically expressed in pounds per square inch (psi).1

When a material is subjected to stress below its UTS, it will return to its original shape once the stress is removed. However, if the stress reaches the UTS, a ductile material will begin to deform permanently and develop a "neck" before breaking. The UTS is a key mechanical property, often measured alongside yield stress and elongation in a tensile test. It is also correlated with hardness measurements.12

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metallurgy
Testing mechanical properties
…the sample, is called the ultimate tensile stress (UTS). The final length minus the initial length, divided by the initial length, is called the elongation. Yield stress, UTS, and elongation are the most commonly tabulated mechanical properties of metals.
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…the sample, is called the ultimate tensile stress (UTS). The final length minus the initial length, divided by the initial length, is called the elongation. Yield stress, UTS, and elongation are the most commonly tabulated mechanical properties of metals.
Read More