Forget what you know about car suspension: Audi is tearing up the rule book and making its latest springs from glass fibre-reinforced composite instead of steel. It’s not gone mad though; this is the future.
The new springs, pictured on the left, are made of thin glass fibres held together in epoxy resin. A machine — which I would really love to see in action — twirls fibres around a small central core at plus or minus 45 degrees to the direction of the coil. Its then coated in epoxy and cured at around 100C.
The resulting springs feature a larger diameter spiral than their steel siblings, and their overall diameter is bigger too. So what’s the point?
Weight, my friend. And lot’s of it. While a steel spring for a mid-size car weighs about 2.7kg, these new GFRP coils weigh just 1.6kg. That’s a 40 per cent saving and adds up to 4kg across the whole car. Sure, that’s not a huge overall percentage gain, but it’s rare a single component can shed so much weight in one go. Oh, they’re also corrosion resistant and require less energy to manufacture.
The new springs will feature in at least one of Audi’s mid-sized models before the end of the year. [Audi]