Fatigue crack growth from small surface cracks in transformation-toughened ceramics

Journal Article · Wed Feb 01 04:00:00 EST 1995 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1995.tb08815.x· OSTI ID:79809

Andreasen, J H ^[1]; Moeller, C V; Karihaloo, B L ^[2]

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1. Univ. of Aalborg (Denmark). Inst. of Mechanical Engineering
2. Univ. of Sydney (Australia). School of Civil and Mining Engineering

A theoretical model based on the theory of complex potentials and dislocation formalism is used to simulate the fatigue crack growth of small cracks in a transformation-toughened ceramic. Assuming power-law crack growth in which the growth rate depends on the effective stress intensity at the crack tip instead of the applied stress intensity, it is shown that the crack growth rate decreases with the applied stress intensity in the initial stage of fatigue crack growth. This is in agreement with existing experimental evidence for the growth of small cracks in Mg-PSZ. New experimental results obtained by in situ observation in a scanning electron microscope of a similar material confirm this behavior. The numerical results also confirm the plausibility of using the steady-state toughness value obtained from quasi-static crack growth as a normalizing parameter in the power-law for fatigue crack growth.

• Sponsoring Organization: USDOE
• OSTI ID: 79809
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 2 Vol. 78; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRACK PROPAGATION
CRACKS
FATIGUE
FRACTURE MECHANICS
MAGNESIUM OXIDES
MATHEMATICAL MODELS
SCANNING ELECTRON MICROSCOPY
STRESS INTENSITY FACTORS
STRESSES
ZIRCONIUM OXIDES