Carbon Fiber Composite Subframe
34 Percent Mass Reduction
The prototype carbon fiber subframe is the result of a research and development project between Magna and Ford to investigate potential mass-reduction benefits and technical challenges of using carbon-fiber-reinforced composites in chassis applications. The subframe is a key part of a vehicle's structure, typically providing a place to attach the engine and wheels while also contributing rigidity and crash management.
In pursuit of lower vehicle weight to reduce emissions and improve fuel efficiency, Magna International Inc., in cooperation with Ford Motor Company, developed a prototype carbon fiber composite subframe which reduces mass by 34 % compared to making a stamped steel equivalent. By replacing 45 steel parts with two molded and four metallic parts, the prototype subframe achieves a 87 % reduction in the number of parts. The moldings are joined by adhesive bonding and structural rivets.
The design has passed all performance requirements based on computer-aided engineering (CAE) analyses. The prototype subframes are now being produced by Magna for component and vehicle-level testing at Ford. The testing phase will evaluate corrosion, stone chipping and bolt load retention, which aren't currently measured by CAE. The project team will also develop a recommended design, manufacturing and assembly process with the experience gained during the prototype build and subsequent testing.
The Advantages of Collaboration
Magna's engineering team – a collaborative effort between the company's body & chassis and exteriors product groups – combined its unique, full-vehicle knowledge on the design, materials and processing to address the challenge of reducing weight using composite materials and manufacturing processes. "We've been a pioneer in the use of lightweight materials for many years now," says Grahame Burrow, President of Magna Exteriors. "First we launched the CF hood for the Cadillac CTS/ATS-V series, followed by a carbon fiber grille opening reinforcement for the Mustang Shelby Cobra GT500. Applying our expertise now to a structural component like the subframe is another step forward as we continue to help our OEM partners meet their goals."
"Collaboration is the key to success in designing lightweight components that can give our customers fuel economy improvements without compromising ride and handling, durability or safety. We must continue to work hard to achieve these lightweight solutions at the most affordable costs. Magna and Ford working together on this carbon fiber composite subframe is a great example of collaboration on advanced materials," says Mike Whitens, Director of Vehicle Enterprise Systems within Ford Research and Advanced Engineering.