yield stress

mechanics

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July 15, 2026

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In mechanics, the yield point is the stress at which a solid material begins to deform permanently. This marks the transition from elastic behavior, where the material returns to its original shape after stress is removed, to plastic behavior, where deformation is irreversible.12

For many materials, a specific yield point isn't clearly defined. In such cases, yield strength is used, representing the stress at which a material undergoes a predetermined amount of permanent deformation, often 0.2 percent.1

When stress exceeds the yield point, the material deforms permanently and does not return to its original shape once the force is removed. This is distinct from tensile strength, which is the maximum stress a material can withstand before breaking. Yield strength is crucial for determining the maximum load mechanical components can handle before damage occurs.32

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stress
Yield stress, marking the transition from elastic to plastic behaviour, is the minimum stress at which a solid will undergo permanent deformation or plastic flow without a significant increase in the load or external force. The Earth shows an elastic response to the stresses caused…
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Yield stress, marking the transition from elastic to plastic behaviour, is the minimum stress at which a solid will undergo permanent deformation or plastic flow without a significant increase in the load or external force. The Earth shows an elastic response to the stresses caused…
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metallurgy
Testing mechanical properties
…most common mechanical properties are yield stress, elongation, hardness, and toughness. The first two are measured in a tensile test, where a sample is loaded until it begins to undergo plastic strain (i.e., strain that is not recovered when the sample is unloaded). This stress is called the yield stress.…
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…most common mechanical properties are yield stress, elongation, hardness, and toughness. The first two are measured in a tensile test, where a sample is loaded until it begins to undergo plastic strain (i.e., strain that is not recovered when the sample is unloaded). This stress is called the yield stress.…
Read More

metallurgy
Mechanical properties
…however, a point called the yield stress will be reached and exceeded. Strain will now increase faster than stress, and, when the sample is unloaded, a residual plastic strain (or elongation) will remain. The elastic strain at the yield stress is typically 0.1 to 1 percent, whereas, with the sample…
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…however, a point called the yield stress will be reached and exceeded. Strain will now increase faster than stress, and, when the sample is unloaded, a residual plastic strain (or elongation) will remain. The elastic strain at the yield stress is typically 0.1 to 1 percent, whereas, with the sample…
Read More