Downsizing through unibody construction, aerodynamics lead lightweight charge

Feb 01, 2010 | 05:45 AM |

Every bright spot comes with a dark side. Such is the case with the auto industry's efforts to slim down vehicles to improve fuel economy and meet ever-tightening emissions standards. Automakers are racing to incorporate lightweight materials to meet their goals, but some of the lightening efforts come with serious sticker shock.

"The use of advanced materials such as magnesium, aluminum and ultra high-strength boron steel offers automakers structural strength at a reduced weight to help improve fuel economy and meet safety and durability requirements," said Robert Parker, director of product communications at Ford Motor Co., Dearborn, Mich.

High-strength steels (HSS) played prominently in the efforts of Japan's Mazda Motor Corp. to shave more than 220 pounds off its much-anticipated 2010 Mazda2 subcompact compared with its predecessor. And Tokyo-based Nissan Motor Co. Ltd. slimmed down its new 370Z roadster by 95 pounds thanks to a wider application of HSS, and for the first time aluminum door panels, an aluminum hatch and an all-aluminum hood (the previous aluminum hood design utilized steel reinforcements).....