A numerical study on the thermal expansion coefficients of fiber

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temperature dependence of the dimensional behavior which results from softening of
the resin.
The elastic solution achieved by Foye in 1968 employed the finite element
method for the first time in the field of micromechanical analysis of unidirectional
composites (Adams & Crane, 1984). This generalized plane strain <strong>study</strong> included
two fiber arrangements, separate and combined loading of five of the six components
of stress, contours of stresses in the matrix around a fiber, determination of
unidirectional lamina composite properties and an evaluation of the accuracy of the
various finite element models.
Adams and Crane (1984) modeled a microscopic region of a unidirectional
composite by finite element micromechanical analysis using generalized plane strain
formulation, but including longitudinal shear loading. Their analysis was capable of
treating elastic, transversely isotropic fiber materials, as well as isotropic,
elastoplastic materials. They used the micromechanical analysis to predict the
stress/strain response into the inelastic range of graphite-epoxy laminate. Their
results were in excellent agreement with available experimental data.
Some of analytical models are critically reviewed and compared with
experimental measurements by Bowles and Tompkins (1989). For the most part,
large discrepancies between the predicted values of the transverse CTE and the test
data are observed, except for the model of Rosen and Hashin (1970). Bowles and
Tompkins (1989) also conducted finite element calculations for two cell geometries,
including doubly periodic square and hexagonal patterns, and showed that their
results were in good agreement with the experimental values and with the Rosen-
Hashin (1970) analysis. The solution for the periodic square pattern provides the
reference for the present investigation.
The thermal expansion response of macroscopically isotropic metal–ceramic
composites was studied through micromechanical modeling by Shen (1998). He
carried out three-dimensional finite element analyses for the entire range of phase