Influence of Textile Architecture on the Mechanical Properties of 3D Woven Carbon Composites

The application of 3D woven composites in advanced structural components is limited by a lack of understanding of the influence of weaving parameters on the final architecture and mechanical properties of composites. This paper investigates the effect of fundamental and easily adjustable weave parameters (pick density and float length) on the mechanical properties (tension, compression and flexure) in 3D woven warp interlock layer-to-layer carbon/epoxy composite structures. The purpose of this paper is to establish a link between the textile and composite performance within this 3D weave architecture. The 3D fabrics, manufactured using a Jacquard loom, are fabricated in three different pick densities: 4, 10 & 16 wefts/cm, with a constant end density of 12 warps/cm from T700S-50C-12k carbon fibre. The pick density with the best mechanical properties is then used for the float length change iteration. The aim is to keep end and pick densities constant in the two float length variation specimens. The mechanical properties of the specimens are affected by the fibre content, tow waviness, misalignment of the load carrying tows and the distribution/size of resin rich areas. This paper depicts a link between the pick density/float length, mechanical properties and failure mechanisms in 3D woven layer-to-layer carbon/epoxy composites.