With the global market for carbon fibre currently greater than 60,000 MT per year and predicted to increase to between 100,000-140,000 MT in the 2020s, carbon fibre recycling is more important than ever. It's estimated that more than 30% of produced carbon fibre ends up as waste during the manufacturing process.
Although there are now cost-effective ways of recovering this carbon fibre waste, there are still barriers to returning these recovered fibres to the market. Limited knowledge and a lack of economic, technical and environmental justifications for using these materials are just some of those barriers.
Organisations around the world are attempting to overcome these barriers; developing cost-effective solutions to both carbon fibre recycling and investigating uses of reclaimed carbon fibre materials. The University of Nottingham is one of these - Professor Steve Pickering has been carrying out research into fibre alignment for high value applications in recycled carbon fibre. Ahead of GOCarbonFibre 2016, we spoke to him to find out more:
Your presentation will be taking a look at developments in fibre alignment for high value applications in recycled carbon fibre, what does this really mean?
To achieve the best properties from carbon fibre reinforced plastics (CFRP) it is important to use as much carbon fibre and as little polymer as possible in a composite. Composites made from new carbon fibre use continuous carbon fibre tow, in which the fibres are aligned and this allows them to pack together more easily to achieve a high volume fraction of carbon fibre in CFRP, typically up to about 60%. Carbon fibres recovered from a recycling process are usually in a fluffy form where the individual fibres are not held together in aligned bundles. With these randomly oriented fibres it is not possible to pack the fibres closely together enough to give high fibre volume fractions. Therefore, if recovered fibres are to be used in high value applications, with high fibre volume fraction, there is a need to align the fibres so that the best properties can be achieved in the composite; properties that compete only with new carbon fibre.
What are the consequences and results of these developments?
We have already achieved a fibre volume fraction of over 60% using our fibre alignment processes, but a high moulding pressure was required to achieve this. We are now developing the technology further to give better alignment at lower, and potentially cheaper, moulding pressures.
Why is it really important to use recycled carbon fibres and what does this mean for the future?
Carbon fibre is a high value material that requires a lot of energy to manufacture. If recovered carbon fibres can be used in high value applications that would otherwise require virgin carbon fibre then this has the potential to save money and be more environmentally sustainable.
Where do you foresee the next 5 years in the carbon fibre industry is headed and do you think the approach towards recycling will change any time soon?
The carbon fibre recycling industry is in its infancy at the moment. Carbon fibre recovered from CFRP waste is already being used in a number of applications, but these are currently of lower value. As more carbon fibre is being produced there are more opportunities for fibre recovery from waste from manufacturing operations and, in due course, more end-of-life components will also be available for recycling. Therefore more recovered carbon fibre will become available and as recycling technology develops there is the potential to use recovered carbon fibre in higher value products.
What are you most looking forward to at the GOCarbonFibre 2016 conference in Hannover?
I am looking forward to finding out more about new applications for carbon fibre and understanding more about where the carbon fibre recycling industry is heading.
It's time that the industry recognised the importance and benefits of using recycled carbon fibres and works together to ensure that recycling becomes an integral part of the carbon fibre market. Join us at GOCarbonFibre 2016 in Hannover this October to ensure you're part of the industry's future. Click here to book your ticket now >>
Professor Pickering will be presenting on the second day of the conference, discussing his research on the developments in fibre alignment for high value applications of recycling carbon fibre in more detail. Click here to view the full programme >>