Pressing ahead with sustainable composites

For years now, engineers have been struggling with a paradox. To make vehicles lighter, and hence more efficient, you often need to adopt materials that are more energy-intensive to process, and sometimes harder to recycle. That’s particularly true of composites. Using traditional techniques, carbon fibre production is around 14 times more energy-intensive than steel production.

Part of the problem is that thermosetting composite parts such as body panels, seat frames or wheels generally need to be cured by the application of vacuum, heat and pressure in an autoclave. Maintaining the heat and pressure required in an autoclave is expensive – circa £500 per cycle and running into the thousands for a part like a Formula 1 tub that requires around eight curing cycles.

For applications where light weight is critical but the extremely high strength-to-weight ratio of traditional carbon fibre isn’t paramount, there is a more affordable and environmentally sustainable option in the form of compression moulding. Instead of an autoclave, this uses a heated press to apply heat and pressure to cure the part, slashing the cycle times. The lower costs and shorter cycle times of compression moulding make it a more attractive proposition for mass production. And when it comes to environmental impact, medium-to-high volume applications are where the real differences can be made.