Experimental Investigation of the Axial Impregnation of Oriented Fiber Bundles by Capillary Forces.

摘要

Capillary impregnation of a viscous liquid into carbon fiber bundles is investigated experimentally. Axial impregnation is examined in which flow occurs primarily parallel to the fibers' axes. For silicone oils, as well as for a curing epoxy system, the kinetics of axial impregnation follow closely h alpha t112 where h is the average displacement of the advancing front and t is the time of impregnation. 'Me impregnation raw are higher than those predicted by models based upon simple geometries. The rates am strongly influenced by the pore size distribution in the fiber bundles. At a given overall average porosity, higher rates of impregnation are observed for samples having a higher pore heterogeneity than those with a narrow distribution of pore sizes. An analysis of the experimental data is presented which allows the effective pore size distribution to be calculated. Carbon fibers, impregnation, porous materials, continuous fiber composites.