Effect of laminate stacking sequence on the high frequency fatigue behavior of SCS-6 fiber-reinforced Si{sub 3}N{sub 4} matrix composites

Journal Article · Sat Nov 01 04:00:00 EST 1997 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/s11661-997-0199-y· OSTI ID:556484

Chawla, N ^[1]

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1. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Materials Science and Engineering

In many potential applications, continuous fiber-reinforced ceramic matrix composites (CFCMCs) will encounter cyclic fatigue loadings at high frequencies (25 Hz or higher). While most of the work in the area of fatigue of CFCMCs, stress-strain hysteresis occurs during fatigue and is associated with energy dissipation in the composite. In addition to this, the repeated friction and sliding between fiber and matrix are responsible for a substantial temperature rise at the fiber/matrix interface. In this study, [0/90] and [{+-}45] SCS-6 (silicon carbide)/Si{sub 3}N{sub 4} composites made by hot pressing were investigated under high frequency fatigue loadings. The angle-ply laminate showed the same extent of heating as cross-ply laminates, but at much lower stress levels. Frictional heating was caused by sliding at the fiber/matrix interface. Temperature rise due to heat generation in the specimens correlated very well with damage in modulus as a function of fatigue cycles in the composites. Matrix microcracking was more predominant in the angle ply than in the cross-ply composite, due to the much lower stiffness of the angle-ply composite in the longitudinal loading direction.

• Sponsoring Organization: National Science Foundation, Washington, DC (United States)
• OSTI ID: 556484
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 11 Vol. 28; ISSN 1073-5623; ISSN MMTAEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
CRACKS
FATIGUE
FIBERS
FREQUENCY DEPENDENCE
FRICTION
HEATING
INTERFACES
SILICON CARBIDES
SILICON NITRIDES
STRAINS
STRESSES