1989 年 38 巻 426 号 p. 307-311
Thermal expansion coefficients of unidirectional carbon fiber reinforced composites were investigated theoretically. Explicit equations for the longitudinal and transverse thermal expansion coefficients of the composite were derived, employing the extended equivalent inclusion method. The anisotropic property of the carbon fiber as well as the elastic interaction among the fibers were taken into account. The formulae obtained are valid for the whole range of fiber volume fraction; 0≤Vf≤1, and they are simple in the form and easy to use. The availability of these formulae was confirmed by the comparison of the predicted values with experimental data on three types of carbon fiber composites. The formulae derived here are applicable not only to carbon fiber/epoxy but also to carbon fiber/metal composites. In the case of carbon fiber/rubber composite, in which the rigidity of rubber is infinitesimal compared to that of carbon fiber, these formulae can be reduced to more simple equations.