Analytical modeling of the interfacial stress state during pushout testing of SCS-6/Ti-based composites

Journal Article · Tue Nov 01 04:00:00 EST 1994 · Acta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-7151(94)90455-3· OSTI ID:6996127

Ghosn, L J; Eldridge, J I ^[1]; Kantzos, P ^[2]

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1. NASA Lewis Research Center, Cleveland, OH (United States)
2. Ohio Aerospace Inst., Brook Park, OH (United States)

Analytical and experimental investigations were performed to determine the stress components responsible for interfacial debonding during pushout testing. The stress distributions along the fiber/matrix interface were modeled using finite element methods. Both thermal residual stresses as well as mechanical stresses were accounted for in the analysis. The analysis was performed for two SCS-6/Ti-based composite systems. The analytical results were calculated based on experimentally determined fiber debonding loads obtained at different specimen thicknesses and testing temperatures. The results of the analysis were consistent with the experimentally observed initiation failure sites. At room temperature, due to large thermal residual shear stresses, the maximum shear stress during thin-specimen pushout was located at the bottom face away from the indenter and was found to control the initiation of interfacial debonding. However, in very thin specimens, the bending stresses control interfacial debonding by causing radial opening at the bottom face. With an increase in temperature the analytical modeling shows that the maximum shear stress moves to the top face, due to the relaxation of the residual shear stresses. However, at high temperature the bending stresses result in failure initiation on the bottom face due to the softening of the matrix and the relaxation of the radial clamping stresses.

• OSTI ID: 6996127
• Journal Information: Acta Metallurgica et Materialia; (United States), Journal Name: Acta Metallurgica et Materialia; (United States) Vol. 42:11; 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
FAILURES
INTERFACES
MATERIALS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
SHEAR PROPERTIES
SILICON CARBIDES
SILICON COMPOUNDS
STRESS ANALYSIS
STRESSES
TESTING
THERMAL STRESSES
TITANIUM ALLOYS
TITANIUM BASE ALLOYS