Airbus is working to take benefit of thermoplastic CFRP material – which holds key advantages over the thermoset-type CFRP that is more commonly used across the air transport sector, including its 100-per cent recyclability.
Jean-Florent Lamèthe, an engineer from Airbus’ Materials and Processes team, explained that thermoplastic CFRP has excellent fatigue and damage tolerance properties, along with shorter manufacturing cycles and lower moisture absorption. It can even be welded, which cannot be done with thermoset-type CFRP.
The key difference between thermoplastic and thermoset CFRP, according to Lamèthe, is what happens during their individual curing processes. "When you put 'raw' thermoset material into an autoclave and 'cook' it, there's a chemical reaction – the actual chemical composition of the material changes,” he said.
With thermoplastic composites, a finished piece and reshape it and it still has the same chemical composition.
"This difference makes thermoplastic composites very attractive. Why? Because Airbus and its suppliers produce literally hundreds of tonnes of scrap thermoplastic composites each year,” added Gael Sarrieu, also of the company’s Materials and Processes team.
“With thermoset, you would need to burn the resin, and all you end up with are the fibres – the remaining 40 per cent (the resin) is lost,” he said. “But with thermoplastic composites, the scrap produces the same amount of recycled material, which could be used in a variety of structural and interior applications.”
Unlike thermoset CFRP, thermoplastic-type composites also do not require curing in an autoclave and can be stored at ambient temperature without need of a freezer and humidity- and temperature-controlled room – equating to significant reductions in energy costs.
There are more and more thermoplastic composites manufacturers entering the market. Still, even before the A350 XWB, Airbus had more than 1,500 reference parts made from thermoplastic composites and its use will continue to grow.
11 February 2015