Audi to use fiber polymer springs in future luxury models

Audi has announced plans to use a new glass fiber-reinforced polymer (GFRP) based springs in their future luxury car offerings. These springs will replace conventional ‘spring steel’ springs and will eventually filter down to the lower end of Audi’s wide spectrum of models.

Set to debut in a large luxury model by the end of 2014 according to Audi, the new springs will offer a much better blend of luxury and comfort in future cars. The glass fiber-reinforced polymer has been jointly developed by Audi and an unnamed Italian supplier. These new springs are light green in color with the fibre strand being noticeably thicker than the standard steel counterpart.

Not only do these new springs look different, more importantly, they are upto 40 percent lighter. Where a steel spring can weight about 2.7 kg, a corresponding glass fiber-reinforced polymer springs will weight not more than 1.6 kilograms. Together the four springs can save up to 4.4 kilograms. Although 4.4 kg might sound inconsequential, springs are generally a part of the suspension geometry’s unsprung weight and a slightly lighter spring can make a world of difference in terms of handling, braking and wheel behavior.

Speaking on the occasion, Dr. Ulrich Hackenberg, Member of the Board of Management for Technical Development at AUDI AG said, “The GFRP springs save weight at a crucial location in the chassis system. We are therefore making driving more precise and enhancing vibrational comfort,”

The core of the springs consists of long glass fibers twisted together and embedded with a special formulae of epoxy based resins. A machine then wraps additional fibers around this core. 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. Another advantage of the glass fiber-reinforced polymer is that they do not corrode even after stone chips and are impervious to chemicals such as wheel cleaners. Audi also claims that the production techniques required producing these glass fiber-reinforced polymer springs require far less energy as compared to their steel counterparts thereby saving energy.