Audi writes new design chapter
Audi has written a new chapter in its lightweight design success story with its next generation Audi A8 featuring a mix of four materials being used for the first time in the weight-bearing body structure.
With a mix of aluminium, steel, magnesium and carbon fibre-reinforced polymer (CFRP) Audi has established a new stage in multi-material construction in the Audi Space Frame (ASF) for the next generation of the Audi A8 – in keeping with the principle ‘the right material in the right place and in the right amount’.
An ultra-high-strength, torsionally rigid rear panel made of CFRP is the largest component in the occupant cell of the new Audi A8, and it contributes 33% to the torsional rigidity of the total vehicle. To optimally absorb longitudinal and transverse loads as well as shearing force, between six and 19 fibre layers are placed one on top of the other, ensuring a load-optimised layout.
A high-strength combination of hot-formed steel components make up the occupant cell, which comprises the lower section of the front bulkhead, the side sills, the B-pillars and the front section of the roof line. Some of these sheet metal blanks are produced in varying thicknesses using tailoring technologies.
The aluminium components make up 58% of the new Audi A8 body, the largest share in the mix of materials. Cast nodes, extruded profiles and sheets are the elements characteristic of the ASF design.
Rounding out the mix of materials is the magnesium strut brace.
In addition to the complete redevelopment of the Audi Space Frame, the production halls at the Neckarsulm location were specially built for the upcoming flagship. A total of 14,400 metric tonnes of steel were needed just for construction of the new, 41-metre-high bodyshop, twice as much steel as was used for the Eiffel Tower in Paris.
The highly complex yet energy-efficient production operation uses 14 different joining processes, including roller hemming at the front and rear door cut outs.