Re-use of carbon composites will be a major factor in the future of the strong, lightweight material.
Boeing has launched several initiatives to find meaningful second uses for carbon-reinforced plastic (CFRP) and now has a new joint venture with BMW. Boeing’s 787 Dreamliner consists of 50% CFRP and BMW is introducing two vehicles with passenger compartments made of carbon fiber next year. Recycling carbon composite material at point of use and the end of product life is critical to both companies. More than two-thirds of the carbon fiber Boeing buys (at up to $30 per pound) ends up as production scrap.
“It is especially important that we plan for the end of life of products made from carbon fiber,” says Larry Schneider, vice president of Product Development in the Commercial Airplanes group at Boeing. “We want to look at ways to reclaim and reuse those materials to make new products. Our work with BMW will help us attain that goal.”
As part of the collaboration agreement, Boeing and the BMW Group will also share carbon fiber manufacturing process simulation approaches and ideas for manufacturing automation. BMW and SGL opened a plant in Moses Lake, Wash. last year that will provide carbon fiber parts for the 2013 i3 and i8 models. Both new models will be assembled in Leipzig, Germany.
The Moses Lake plant is now producing 3,000 tons of carbon fiber a year and BMW expects to increase the capacity five-fold.
Carbon composites are difficult to recycle for the same reasons they are so strong. The matrix plastic that holds the carbon fiber prepregs in place does not melt. The types of plastic used in packaging such as polyethylene are thermoplastic and can easily be remelted and re-used. The other issue is that the carbon fiber has significantly greater value than the plastic.
Researchers at the High-Performance Materials Institute at Florida State University reported at the Automotive Composites Conference and Exhibition in Troy, Mich. recently that supercritical fluid solvents are a possible approach.
Boeing is also now investing $1 million annually (for at least three years) in strategic research collaboration with the University of Nottingham’s Faculty of Engineering in all its composites recycling activities. The aircraft manufacturer is also working with engineering plastics compounder RTP to find new applications for reclaimed CFRP scrap.