Smooth as glass: Audi develops synthetic springs

AUDI will start to fit some of its cars with springs made from glass and plastic before the end of the year as it attempts to cut costs and weight from future vehicles.

The springs will dip into Audi’s emerging technology, though, with an elastic glass fibre core wrapped in a protective plastic shell similar to other fibreglass reinforced plastic body parts including panels.

According to Audi, the new springs developed in partnership with an Italian supplier are 40 percent lighter than a metal equivalent, and just as durable – even when chipped by a stone.

According to the car-maker, replacing four steel springs with the carbon fibre versions will cut about 4.4 kilograms of weight out of a vehicle, half of which is unsprung mass, or the weight of the wheel and suspension components alone.

According to Audi, the core of the springs consists of glass fibres twisted together and impregnated with epoxy resin.

“A machine wraps additional fibres around this core — which is only a few millimetres in diameter — at alternating angles of plus and minus 45 degrees to the longitudinal axis,” Audi’s description of the springs said.

“These tension and compression plies mutually support one another to optimally absorb the stresses acting on the component.

“In the last production step, the blank is cured in an oven at temperatures of over 100 degrees Celsius.”Glass fibre-based springs is not the only technological leap Audi is planning to make. The German luxury car-maker is also developing a 48-volt electrical system that is optimised for a new generation of idle-stop engines, and electric turbochargers that remove low-down lag when accelerating from a standing start.