1. Fatigue thresholds of precracked specimens predicted by modified strip-yield model for plasticity-induced crack closure.
- Author
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Tanaka, K. and Akiniwa, Y.
- Subjects
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CRACK closure , *MATERIAL fatigue , *FATIGUE limit , *FRACTURE mechanics , *YIELD stress , *FATIGUE crack growth , *CRACK propagation (Fracture mechanics) - Abstract
• The effects of precrack lengths and material yield stress on crack closure development are examined. • A new master curve equation is proposed for the cyclic R-curve. • The fatigue thresholds of materials with defects are successfully derived. A strip-yield model modified to leave plastically deformed stretch in the wake of the advancing crack tip is applied to simulate the development of plasticity-induced crack closure with crack extension from precracks with various lengths under the stress ratio R = 0. The effects of precrack length and yield stress on fatigue thresholds were systematically examined. Because of a sharp increase of crack opening stress with crack extension, the effective stress intensity range Δ K eff drops initially and then turns to increase. Assuming the threshold value of Δ K eff for steels, a master curve equation is proposed for the cyclic R-curve. The effects of precrcrack length and material yield stress on fatigue thresholds are successfully derived. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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