Aston Martin's new DB9 luxury coupe replaces the DB7, the best-selling car in the company's history. The carmaker, part of Premier Automotive Group, Ford Motor Co.'s luxury-car division, assembles the DB9 at its plant in Gaydon, England.
The DB9 has an aluminum-bonded body frame. Hydro Aluminium supplies the body frame, which is the most structurally efficient in the world, taking into account strength, torsional rigidity and weight.
Dow Automotive supplies the nonconductive adhesive technology that is used to bond the exterior composite body panels to the complete frame. The frame itself is also bonded using a separate Dow adhesive. The US-based supplier had to create special adhesives for the carmaker.
"Aston Martin's manufacturing process requires a longer open time [the time between applying adhesive and bonding two surfaces]," says Detlef Symietz, an r&d scientist with Dow Automotive. The DB9 is largely hand-built so certain pieces are not bonded as quickly as they would be if they were on an assembly line. In addition, the adhesive must not react with any of the ultra low-weight metal and composite surfaces it touches, Symietz says.
The front fenders, which are attached to the frame with Dow's adhesives, come from UK-based composite parts specialist Mitras Automotive and are made from sheet-molded compound.
"SMC allows design freedom, which other materials cannot offer," says Andrew Proctor, account executive at Mitras. For instance, Proctor says the SMC can be cut more accurately than steel so critical features such as the DB9's headlight aperture can be molded with "faultless repeatability." SMC is less expensive than steel and weighs about 20 percent less.