TWI 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:
≈20°C),
N/mm2
| σy (-40°C),
N/mm2
| σy (-100°C),
N/mm2
| σy (-150°C),
N/mm2
|
| 300 | 350 | 432 | 562 |
| 600 | 650 | 732 | 862 |
Reference
G R Irwin: 'Linear fracture mechanics, Fracture Transition and Fracture Control', Eng. Fract. Mechs, 1968, Vol.1 pp 241-257.
