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Energy Dissipated in Fatigue and Creep Conditions
Stanisław Mroziński1, Zbigniew Lis1, Halina Egner2
1Faculty of Mechanical Engineering, UTP University of Science and Technology, Al. Prof. Kaliskiego 7, 85-796 Bydgoszcz, Poland.
Materials (Basel, Switzerland)
|August 27, 2021
Summary
This study on P91 steel at 600°C reveals that the sequence of fatigue and creep loading significantly impacts material lifespan and accumulated fracture energy. Understanding this loading order is crucial for predicting component durability.
Area of Science:
- Materials Science
- Mechanical Engineering
- Metallurgy
Background:
- P91 steel is a critical material for high-temperature applications.
- Understanding material behavior under combined loading is essential for structural integrity.
- Fatigue and creep are significant degradation mechanisms at elevated temperatures.
Purpose of the Study:
- To investigate the effects of combined variable and constant load conditions on P91 steel.
- To analyze the influence of loading sequence on fatigue life and energy accumulation.
- To apply an energetic description to characterize the fatigue process.
Main Methods:
- Experimental testing of P91 steel samples.
- Application of combined variable and constant load programs at 600°C.
- Analysis using the energetic description of the fatigue process.
Main Results:
- The order of fatigue and creep loading affects fatigue life.
- The sequence of loading influences the total energy accumulated until fracture.
- Energetic parameters correlate with the observed material degradation.
Conclusions:
- The sequence of applied loads critically determines the performance and failure of P91 steel components.
- An energetic approach provides valuable insights into fatigue-creep interactions.
- Design and operational strategies should consider the loading sequence for enhanced component reliability at high temperatures.
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