Dome Co Ltd exhibited a lightweight concept car that is based on Honda Motor Co Ltd's Insight hybrid car and has exterior components made of carbon fiber reinforced plastic (CFRP) at SAMPE JAPAN 2009.
Its front hood, front and rear bumpers, fenders, doors, roof, rear hatch and wheels are made of CFRP, making its weight 45kg lighter than the Insight. For example, the weights of the fender and front door were reduced from 2.2kg to 0.8kg and 14kg to 5.5kg, respectively, by using CFRP instead of steel.
The CFRP wheel weighs 4.5kg while the aluminum wheel weighs 8.1kg. The CFRP bumper is 3.1kg in weight, which is lighter than the 6.3kg of the resin bumper. And the glass part of the rear hatch was replaced by a CFRP part.
This time, the doors and wheels on the left side were not replaced with CFRP parts. So, it is possible to further reduce the weight of the vehicle by replacing them, Dome said. The exhibited car was equipped with a CFRP under panel (24.5kg) in the lower part of its body to improve its aerodynamic characteristics; therefore, the actual weight of the car is 20.5kg lighter than that of the Insight.
The CFRP exterior components and the under panel improved downforce and reduced air resistance at the same time, improving fuel efficiency. The air resistance decreased by 14%, and the downforce increased by 120% for the rear wheels and by 11% for the front wheels. Dome considers that those methods, in addition to the light weight, can improve fuel efficiency by about 10% depending on traveling speed.
The exhibited parts were made by using prepreg. And the company does not have a plan to commercialize them. It aimed to make it known that CFRP can be used for various parts and expand its use not only to exterior parts but also to interior parts.
Among the exhibited components, the CFRP front hood is most likely to be commercialized because there has already been a commercialized CFRP front hood, Dome said.