stress-relaxation test

mechanics

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July 14, 2026

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The stress-relaxation test is a mechanical testing method used in physics and chemistry to measure how a system responds to an external stress over time. When a system is subjected to a sudden change, like a rise in temperature or pressure, it takes time to re-equilibrate. In a stress-relaxation test, a specific displacement or strain is applied to a material specimen, and the resulting drop in load over time is measured. This test is particularly useful for studying viscoelastic materials, which exhibit a delayed response to stress. The data from stress-relaxation tests can also be used to predict a material's creep behavior.12

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deformation and flow
…procedure is known as a stress-relaxation test. The physical reasons for this behaviour are too complex to be explained by any simple molecular model. Such behaviour is characteristic of glass, rubber, many plastics, and some metals.
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…procedure is known as a stress-relaxation test. The physical reasons for this behaviour are too complex to be explained by any simple molecular model. Such behaviour is characteristic of glass, rubber, many plastics, and some metals.
Read More

materials testing
Creep test
…response is measured by the stress-relaxation test. A prescribed displacement or strain is induced in the specimen and the load drop-off as a function of time is measured. Various viscoelastic theories are available that permit the translation of stress-relaxation test data into predictions about the creep behaviour of the material.
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…response is measured by the stress-relaxation test. A prescribed displacement or strain is induced in the specimen and the load drop-off as a function of time is measured. Various viscoelastic theories are available that permit the translation of stress-relaxation test data into predictions about the creep behaviour of the material.
Read More