Fatigue crack growth in fiber-reinforced metal-matrix composites

Journal Article · Fri Jul 01 04:00:00 EDT 1994 · Acta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-7151(94)90320-4· OSTI ID:7028285

Bao, G ^[1]; McMeeking, R M ^[2]

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1. Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Mechanical Engineering
2. Univ. of California, Santa Barbara, CA (United States). Dept. of Mechanical and Environmental Engineering

Fatigue crack growth in fiber-reinforced metal-matrix composites is modeled based on a crack tip shielding analysis. The fiber/matrix interface is assumed to be weak, allowing interfacial debonding and sliding to occur readily during matrix cracking. The presence of intact fibers in the wake of the matrix crack shields the crack tip from the applied stresses and reduces the stress intensity factors and the matrix crack growth rate. Two regimes of fatigue cracking have been simulated. The first is the case where applied load is low, so that all the fibers between the original notch tip and the current crack tip remain intact. The crack growth rate decreases markedly with crack extension, and approaches a steady-state.'' The second regime occurs if the fibers fail when the stress on them reaches a unique fiber strength. The fiber breakage reduces the shielding contribution, resulting in a significant acceleration in the crack growth rate. It is suggested that a criterion based on the onset of fiber failure may be used for a conservative lifetime prediction. The results of the calculations have been summarized in calibrated functions which represent the crack tip stress intensity factor and the applied load for fiber failure.

• OSTI ID: 7028285
• Journal Information: Acta Metallurgica et Materialia; (United States), Journal Name: Acta Metallurgica et Materialia; (United States) Vol. 42:7; ISSN 0956-7151; ISSN AMATEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
CRACK PROPAGATION
DATA
FAILURES
FATIGUE
INFORMATION
MATERIALS
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
NUMERICAL DATA
SILICON CARBIDES
SILICON COMPOUNDS
THEORETICAL DATA
TITANIUM ALLOYS