Mould tools used to produce carbon fibre parts must generally be made from carbon fibre due to the need to match the very low coefficient of thermal expansion (CTE) of carbon. These materials are expensive and have high embodied CO2, especially when considering that the moulds are often only used a few times to produce limited runs or even one-off parts before being scrapped. This limits the use of carbon fibre to high-end applications, restricts profitability and has a high impact on the environment.
Flax natural fibre has significantly lower cost and environmental impact, and it has been shown to work well with carbon in a hybrid lay-up. Therefore flax could potentially be used to replace carbon fibre in composite moulds, thereby reducing costs and environmental impact.
Composites Evolution tests have found Carbon/flax hybrid tooling to have the following benefits:
- 20-40% lower material cost
- 12-15% lower weight
- Same thickness
- Similar dimensional stability
- Comparable surface finish
- Reduced carbon fibre waste
- Lower environmental impact
* Based on a typical ‘1-8-1’ carbon tooling lay-up (1 x 200gsm, 8 x 650 gsm, 1 x 200 gsm) where the middle 4 layers of 650 gsm carbon have been replaced with Biotex Flax 400 gsm 2×2 twill.
Composites Evolution can supply Biotex Flax for tooling as dry fabric for infused tools or impregnated with epoxy resin for prepreg tools.
We would recommend our materials for the following tool manufacturing processes:
- Vacuum infusion (dry fabric)
- Autoclave cure (prepreg)