Composites Evolution develops hybrid tooling prepregs

Composites Evolution Ltd. (Chesterfield, UK), in collaboration with with molder KS Composites (Melton Mowbray, UK), has developed a new tooling prepreg system based on a hybrid combination of carbon fiber and flax fiber reinforcements, aimed at reducing the cost of carbon fiber tools. In the new hybrid tooling system, several of the carbon bulking plies are replaced with flax fiber. Composites Evolution says this is possible because the thermal expansion properties of flax fibers are sufficiently similar to those of carbon fibers. The result, says the company, is a hybrid carbon fiber/flax fiber tool in which the material costs are reduced by up to 15% compared to an all-carbon fiber tool. Secondary benefits include a reduction in tool weight of up to 15% and reduced environmental impact from the use of sustainable flax. In trials performed by KS Composites, a hybrid carbon fiber/flax fiber tool has successfully completed more 400 thermal cycles. A mold manufactured with the material is now used in production.