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Intrinsic Fatigue Limit and the Minimum Fatigue Crack Growth Threshold
Mirco D Chapetti1, Nenad Gubeljak2, Dražan Kozak3
1Laboratory of Experimental Mechanics, INTEMA, National University of Mar del Plata-CONICET, Av. Colón 10.850, Mar del Plata 7600, Argentina.
Materials (Basel, Switzerland)
|September 9, 2023
Summary
This study investigates the intrinsic fatigue limit, crucial for predicting the lifespan of materials with larger defects. Understanding this limit enhances the reliability and safety of mechanical components, especially in additive manufacturing.
Area of Science:
- Materials Science
- Mechanical Engineering
- Fracture Mechanics
Background:
- Predicting fatigue life is essential for mechanical component reliability.
- Fracture mechanics aids fatigue life estimation for small cracks.
- Large defects necessitate understanding the intrinsic fatigue limit for accurate resistance prediction.
Purpose of the Study:
- To examine experimental evidence of the intrinsic fatigue limit.
- To correlate the intrinsic fatigue limit with non-propagating cracks.
- To analyze fracture mechanics models for small crack propagation and their limitations.
Main Methods:
- Introducing fracture mechanics models for small crack propagation.
- Defining and applying the concept of intrinsic fatigue limit.
- Reanalyzing a previous publication using the intrinsic fatigue limit concept.
- Exploring and applying methods to estimate the intrinsic fatigue limit.
Main Results:
- Analysis of disparities and limitations in small crack propagation models.
- Application of the intrinsic fatigue limit concept to experimental data.
- Highlighting the importance of the intrinsic fatigue limit for materials with processing-induced defects.
Conclusions:
- The intrinsic fatigue limit is critical for materials with defects larger than microstructural size.
- Accurate prediction of the intrinsic fatigue limit is vital for additive manufactured alloys.
- Further research is needed to clarify and predict the intrinsic fatigue limit effectively.
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