Audi showed off the “Space Frame” for its upcoming next-generation A8 on Wednesday, announcing a body-in-white that used more unique classes of materials than any other A8.
About 58 percent of the structure is aluminium. Another large portion is ultra-high-strength or conventional steel. The front strut tower is magnesium, for 28 percent less weight and more rigidity. The largest piece of the passenger cage is a carbon-fibre rear panel adding 33 percent to the torsional rigidity. Overall, torsional rigidity, which Audi calls “the critical parameter for precise handling and pleasing acoustics” better than the outgoing A8 by 25 percent.
As you might expect, you just can’t weld all of these disparate materials, and Audi boasted of employing 14 different joining methods at its Neckarsulm factory.
These include the “cold” joining technique of roller hemming at the front and rear door cutouts to connect the aluminium side-wall frame to the ultra-high-strength steel in the B-pillar, roof rails and sills. According to Audi, this granted the OEM an extra 1.4 inches for the doors over the outgoing A8, making it easier to exit the vehicle and also see better around the A-pillar.
This article is courtesy of John Huetter and Repairer Driven News . Check out their website at http://www.repairerdrivennews.com where you will find this and so much more information.