No metals in e-tron – and future Audi – coil springs
Fibreglass reinforced springs are the suspension future for AudiAudi engineers working with Italian plastics manufacturer Sogefi have developed a fiberglass-reinforced plastic epoxy coil spring that allegedly matches the performance of steel springs but saves about 40 per cent in weight.
The ‘wire’ coil in the plastic spring is thicker, and the spring’s overall diameter is greater than a conventional steel spring but the reduction in mass (especially unsprung mass) translates directly into ride, handling and fuel economy benefits.
Steel springs in a conventional Audi A4 weigh 2.66kg apiece but the new ‘FRP’ springs for the same model weigh 1.53kg each – more than 40 per cent less.
The fiberglass-reinforced plastic springs will roll out in production in late 2012 in the (electric) Audi e-tron. In 2013 they’ll be rolled out into midsize and larger models.
Long-term trials are under way now, including rig tests designed to simulate 300,000km of average moving.
Engineers are working on tuning the spring characteristics using production methods, as well as reducing the size to match current steel springs – something they claim will take a few years.
Currently they’re bright green, but Audi’s tech types say black is just an injection of carbon away. For overt owners, they’re working on bright red and blue springs… Aftermarket tuners, eat yer hearts out, at least until the tech catches up.
Full story in - yawn - European Plastics News.