Effect of processing variables on interfacial properties of an SiC-fiber-reinforced reaction-bonded Si[sub 3]N[sub 4] matrix composite

Journal Article · Sat Oct 01 04:00:00 EDT 1994 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1994.tb04643.x· OSTI ID:6765187

Singh, D; Singh, J P; Majumdar, S; Kupperman, D S; Cowdin, E ^[1]; Bhatt, R T ^[2]

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1. Argonne National Lab., IL (United States). Energy Technology Division
2. NASA Lewis Research Center, Cleveland, OH (United States). Army Propulsion Directorate

Fiber/matrix interfacial debonding and frictional sliding stresses were evaluated by single-fiber pushout tests on unidirectional continuous silicon-carbide-fiber-reinforced, reaction-bonded silicon nitride matrix composites. The debonding and maximum pushout loads required to overcome interfacial friction were obtained from load-displacement plots of pushout tests. Interfacial debonding and frictional sliding stresses were evaluated for composites with various fiber contents and fiber surface conditions (coated and uncoated), and after matrix densification by hot isostatic pressing (HIPing). For as-fabricated composites, both debonding and frictional sliding stresses decreased with increasing fiber content. The HIPed composites, however, exhibited higher interfacial debonding and frictional sliding stresses than those of the as-fabricated composites. These results were related to variations in axial and transverse residual stresses on fibers in the composites. A shear-lag model developed for a partially debonded composite, including full residual stress field, was employed to analyze the nonlinear dependence of maximum pushout load on embedded fiber length for as-fabricated and HIPed composites. Interfacial friction coefficients of 0.1--0.16 fitted the experimental data well. The extremely high debonding stress observed in uncoated fibers is believed to be due to strong chemical bonding between fiber and matrix.

• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6765187
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 77:10; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
DATA
EXPERIMENTAL DATA
FAILURES
FRICTION
INFORMATION
INTERFACES
MATERIALS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
PNICTIDES
SILICON CARBIDES
SILICON COMPOUNDS
SILICON NITRIDES
SLIDING FRICTION
TESTING