Fatigue crack initiation and multiplication of unnotched titanium matrix composites

Journal Article · Fri Nov 20 04:00:00 EST 1998 · Acta Materialia

DOI:https://doi.org/10.1016/S1359-6454(98)00249-3· OSTI ID:302380

Her, Y C; Wang, P C; Yang, J M ^[1]

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1. Univ. of California, Los Angeles, CA (United States). Dept. of Materials Science and Engineering

Fatigue crack initiation and multiplication of the unnotched SCS-6 silicon carbide fiber-reinforced titanium matrix composites with different matrix and interfacial properties have been investigated experimentally and analytically. Ti-15V-3Al, Ti-6Al-4V, and Ti-22Al-23Nb were chosen as matrix materials. The initiation and propagation of each individual matrix crack as a function of fatigue cycles and applied stress levels were carefully monitored. The statistical distribution of crack growth rates in each composite has been constructed and analyzed. The evolution of normalized matrix crack density and stiffness reduction of these composites under fatigue loading also has been characterized. A modified shear-lag model, coupled with the strain-life equation and a fiber bridging model were used to predict the fatigue crack initiation life, matrix crack growth rate, normalized matrix crack density, and residual stiffness of the composites. The predicted fatigue properties correlated well with experimental results.

• OSTI ID: 302380
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 18 Vol. 46; ISSN 1359-6454; ISSN ACMAFD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
COMPOSITE MATERIALS
CRACK PROPAGATION
FATIGUE
MATHEMATICAL MODELS
NIOBIUM ALLOYS
REINFORCED MATERIALS
SILICON CARBIDES
TITANIUM BASE ALLOYS
VANADIUM ALLOYS