Carbon frame design for automotive body

• Intrado concept car based on carbon-fiber reinforced plastic (CFRP) tubes
• “Floating” centre console beam connects passenger compartment and powertrain with carbon frame
• Winner of JEC Innovation Award, Category: Jury Prize

Hyundai Motor Company, in cooperation with Lotte Chemical, Hyosung Corporation and Axon Automotive, has developed an innovative carbon frame for the automotive body of the Intrado concept car. This innovation is also the winner of this year’s JEC Innovation Award.

Frame formed from precisely-shaped continuous loops

At the core of the frame around which the Intrado concept car is based are carbon-fiber reinforced plastic (CFRP) tubes which are as flexible as rope. By aligning and curing them with a mixture of carbon fiber-reinforced plastics, the resulting structure becomes rigid and strong. The frame is formed from precisely-shaped continuous loops made from the newly-formed material. These serve as self-contained modular frames for the roof, hood and even the entire aperture for the door on either side of the car, which are then bonded to each other along their lengths at ambient temperature. The seals of the opening panels shut directly against these frames, further reducing weight and showcasing the carbon fiber whenever the doors, hood or trunk are opened.

“Floating” centre console beam connects passenger compartment and powertrain with carbon frame

By bonding the carbon loops along their lengths, rather than at cross-sections, the Intrado’s frame is stronger and suffers from less torsional stresses, meaning the agility and precision of the engineering remains constant. Additionally, the “open” corners allow the designers greater flexibility. Running along the length of the Intrado is a “floating” centre console beam. This beam provides the Intrado with its special strength in addition to connecting the passenger compartment and powertrain with the carbon frame. It serves as a mounting point for essential controls and protective padding, and also supports the frame’s integration with the fuel cell powertrain and the passenger compartment.

Design makes car more repairable than typical carbon fiber structures

The design of the Intrado make it more repairable than typical carbon fiber structures as damaged sections, or parts of sections, can be repaired without using expensive tooling or ovens. The strength and rigidity of this central structure also allows body panels to be constructed from any material, giving designers greater flexibility and further aiding repairability. The lightweight structure of the Intrado is formed from a mixture of advanced materials, and demonstrates Hyundai’s and its collaborators’ desire to produce lighter, stronger cars that are even better to drive and simpler to repair. By building the Intrado with advanced carbon fiber-reinforced composites, a 50% saving in the overall weight is achieved compared to similar steel structures.