Cyclic Thermal Fatigue vs Creep Fatigue in Steel
Cyclic Thermal Fatigue vs Creep Fatigue in Steel
(OP)
Hi All,
Could someone help me with the following question. Which of the following steel structure scenarios will fail first:
1. The steel structure operating at a constant temperature of 300 °C (creep fatigue)
2. The steel structure operating at temperatures cycling continuously between 100 °C and 300 °C, cycle period 1 hour. (cyclic thermal fatigue)
Thanks
Could someone help me with the following question. Which of the following steel structure scenarios will fail first:
1. The steel structure operating at a constant temperature of 300 °C (creep fatigue)
2. The steel structure operating at temperatures cycling continuously between 100 °C and 300 °C, cycle period 1 hour. (cyclic thermal fatigue)
Thanks





RE: Cyclic Thermal Fatigue vs Creep Fatigue in Steel
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RE: Cyclic Thermal Fatigue vs Creep Fatigue in Steel
Few materials exhibit creep at 300C; 425 C + is a better choice. And fatigue is a phenomena of alternating stresses; a constant tress state does not generate fatigue damage.
The rate of life consumption for both creep and for fatigue are well known for properly formed materials, but the combined failrue modes of creep + fatigue simultaneoulsy operating on the workpiece is yet a work i progress and the object of many pHd theses.
"Nobody expects the Spanish Inquisition! "
RE: Cyclic Thermal Fatigue vs Creep Fatigue in Steel
We have a carbon steel gas duct transporting furnace off gas to a bag house. The shell temperature of the gas duct cycles between 100 °C and 300°C every hour on a daily basis due to a change in temperature of the gas inside the duct. We need to replace some of the duct section every 2 years because of deformation. My question is the deformation because of creep failure at high temperature or cyclic thermal fatigue? Will we reduce the duct deformation over time if keep the shell temperature at 300 °C.
RE: Cyclic Thermal Fatigue vs Creep Fatigue in Steel
RE: Cyclic Thermal Fatigue vs Creep Fatigue in Steel
RE: Cyclic Thermal Fatigue vs Creep Fatigue in Steel
"Nobody expects the Spanish Inquisition! "