BMW i-project cars close the carbon loop
The BMW i-project cars’ use of recycled carbon fibre has highlighted an emerging market where technologists are creating the means to re-use a valuable material. David Vink reviews the developments in this feature.
BMW uses recycled carbon fibre (rCF) in the epoxide resin based CF reinforced plastic (CFRP) roof of the i3 electric drive and i8 plug-in hybrid cars, as well as the i3’s PU-CFRP rear seat shell. BMW produces the roofs in Landshut with fabric using virgin and recycled fibre fabric woven by its CF joint venture partner SGL Automotive Carbon Fibers (SGL ACF) in Wackersdorf. But FS Fehrer moulds the seat with non-woven rCF from SGL ACF and BASF polyurethane, saying it is the first PU-CFRP serial application.
SGL ACF talked on its Composites Europe 2013 stand of producing oriented (anisotropic) and isotropic non‑woven fleece materials from CFRP waste materials. It described its rCF yarns as “stretch-broken”, with “special properties” such as high tensile strength and low yarn count, which apparently makes them especially suitable for processing into textile fabrics. CF non‑woven fleeces were developed over a three-year period together with the TITK Thuringia institute for textile and plastics research.