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Can the yield strength of ferritic steels at temperatures below ambient be estimated from room temperature values?


Frequently asked questions

For ferritic steels, the yield strength at temperatures (T) other than room temperature (RT) can be estimated using the following relation published by Irwin[1].

σy(T) = σy(RT) + 100,000/(1.8T + 491) - 190

σy in N/mm2, T in °C.

To ensure conservative predictions, lower bound room temperature yield strength values should be used as input.

Examples are given below:

σy (-40°C),
σy (-100°C),
σy (-150°C),
300 350 432 562
600 650 732 862


G R Irwin: 'Linear fracture mechanics, Fracture Transition and Fracture Control', Eng. Fract. Mechs, 1968, Vol.1 pp 241-257.

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