Through-Thickness Thermal Conductivity in Composites Based on 3-D Fiber Architectures

The use of highly thermally conductive fibers can improve the in-plane heat flow of structural composites based on unidirectional tapes or 2-D laminates with little effect on the heat flow out-of-plane. One method of achieving significant increase in the through-thickness thermal conductivity is to manufacture composites based on 3-D fiber architectures with high thermal conductivity fibers in the through-thickness direction. To demonstrate the effectiveness of this method, orthogonal 3-D woven preforms with pitch carbon tows and with copper tows in the through-thickness direction were manufactured and infused with epoxy resin. Test samples from these composites achieved 4 - 7.2 W/mK in the through-thickness direction.