Quantitative description of the microstructure of composites. Part I: Morphology of unidirectional composite systems

For the purpose of micromechanical modeling the behavior of unidirectional composite materials it is necessary to identify the descriptors that in the best way characterize the spatial dispersion of fibers. By introducing a second-order intensity function and the Dirichlet tessellation, the statistical analysis of fiber distribution has been carried out. The analysis has been performed for three distributions obtained experimentally and for several simulated distributions. It is shown that customary assumptions about complete randomness or perfect regularity of the dispersion may be in error, compared with real situations. A simple micro-mechanical model illustrates the influence of distribution statistics on the calculated stress field.