Carbon fibre composites make light work of reinforcing BMW 7 series

Carbon fibre composites from Hexcel Corporation are being used in the production of the BMW 7 series to reinforce the metal shell of the B-pillar and save weight.

Hexcel supplies BMW with preforms made of unidirectional carbon prepreg set in various orientations and combined with adhesive. The prepreg is made from Hexcel’s HexPly M77 resin system that cures in 1.5 minutes at 160°C.

To meet the requirements for series production in the automotive industry, Hexcel has installed a fully automated production line in Austria that converts unidirectional prepreg into bidirectional preforms in seconds.

The process, Hexcel says, allows prepreg plies of different weights and orientation to be combined in the same ply-book and includes automated cutting, camera-assisted ply positioning, integration of adhesive and automated packing.

This unique, fully automated production cell makes B-pillar preforms for up to 500 cars each day, which Hexcel says meets the high production rates required by automotive manufacturers and the high quality expectations of premium car manufacturers.