Carbon fibre composite door made with Momentive Specialty Chemicals epoxy resin.
Carbon fibre composite door made with Momentive Specialty Chemicals epoxy resin.

The carbon fibre/epoxy door and window frame profile was produced by Benteler-SGL for 2013 and later Porsche 911 GT3 Cup coupes.

The composite component was manufactured by high pressure resin transfer moulding (HP-RTM) using Momentive’s EPIKOTE™ 04695-1/EPIKURE™ 05357 epoxy resin system, Sigrafil® type C40 carbon fibre supplied by SGL Group, and polyester fibre.

The component’s Class A surface was finished in the body colour.

60% weight reduction

The part has a simplified, integrated 2-piece design with a single structural inner piece incorporating the header, and a Class A outer panel.

The door is a lightweight, trimmed body structure weighting 5.5 kg, compared to 15 kg for the standard series door. The raw body of the door weights 4 kg and the polycarbonate window and paint weigh 1.5 kg.

The inner and outer shells are manufactured via HP-RTM, and the outer shell is designed as a 'micro-sandwich' to achieve the requisite buckling strength and performance at the minimum weight.

The composite door offers:

  • a greater than 60% weight reduction compared with metal;
  • lower vehicle centre of gravity;
  • Class A appearance; and
  • short cycle-time production.

The HP-RTM process is set up in automated steps, accommodating build rates from low volume (500 pieces/year) to high volume (up to 100,000 pieces/year) with a fully automated process line.

The 2014 SPE ACCE took place on 9-11 September in Novi, Michigan, USA.