The Effect of Variable Fiber Aspect Ratio on the Stiffness and Thermal Expansion Coefficients of a Short Fiber Composite

The effect of variable fiber aspect ratio l/d on the thermo-mechanical properties of aligned short fiber composites is analytically studied by use of the Eshelby's equivalent inclusion method. Then, the thermo-mechanical properties of the composite predicted for a given density function (l/ d) are compared with those obtained for the mean value of (l/ d). Based on this comparison, the validity of using the mean value is discussed. As a demonstration, the results on two types of a short fiber composite are presented, SiC whisker/Aluminum and Carbon fiber/Epoxy composites.