Hexcel, HP Composites develop carbon fiber Class A body panels

It was announced on Sept. 28 that Hexcel (Stamford, Conn., U.S.) has collaborated with HP Composites S.p.A (HP Composites, Ascoli Piceno, Italy), which produces carbon fiber components for automotive and motorsports, to develop carbon fiber Class A body panels. Hexcel HexPly XF surfacing technology is being extensively used by the Italian component producer to manufacture external body panels and other components for supercars such as Alfa Romeo’s (Milan, Italy) new supersport sedans, the Giulia GTA, and GTAm.

With five production plants in Italy, HP Composites reports that it has built a track record of high-performance composite successes on both road and racetrack. HP has combined this processing expertise with Hexcel HexPly XF3 surfacing material, HexPly M47 and HexPly M49 prepregs, working to the highest standards set by prestigious supercar OEMs and leading motorsport teams.

“Our long-term experience has given us a detailed understanding of the critical features that influence how prepregs and surfacing technologies interact with different production processes,” says Abramo Levato, general manager, HP Composites S.p.A. “The relationship we have with Hexcel is both highly technical and highly supportive. As a result we have a complete material package for high-quality Class A body panels that are formulated specifically with our requirements in mind.”

HP has also developed its own proprietary press and compression molding processes, compatible with HexPly XF3 and other HexPly prepregs.

Similarly, Hexcel’s automotive composites portfolio is the result of decades of industry experience and the creation of strategic partnerships to develop and optimize leading-edge technologies. HexPly XF3 is an epoxy prepreg surface material, developed with processing input from the HP Composites team to address the challenges of producing high-quality Class A automotive body panel surfaces with excellent resistance to aging tests.

Applied as the first ply in the mold and cured at 120-180˚C in an autoclave, HexPly XF3 is said to produce a smooth part surface with no porosity, that requires minimal preparation for painting. It is also supplied in an easy-to-handle roll format with good tack and drapability. After curing, it can be easily prepared for painting with a rapid sanding process. HP Composites has incorporated automated robotic sanding techniques for this finishing stage with the paint-ready HexPly XF3 surface providing excellent paint adhesion according to EN ISO 2409.

According to HP Composites, it typically uses autoclave processing for HexPly XF3 parts, maximizing weight savings and structural performance of the final components. In addition, HP has also developed its own proprietary press and compression molding processes, including Air Press Moulding technology, compatible with HexPly XF3 and other HexPly prepregs for higher volume production series that require increased production rates.

“Combining the expertise of HP with a strong technical interaction and collaborative dialogue, Hexcel and HP were together able to develop the optimum HexPly XF surfacing technology,” says Claude Despierres, VP sales and marketing, Hexcel. “With HexPly XF3 we satisfy the toughest industry standards.”