The target is a 17 percent reduction in mass. The Task Force, which has representatives from steel companies, wheel manufacturers, wheel trim suppliers and OEMs, continues to work closely with automakers who seek reduced weight without sacrifice to appearance, performance, safety and affordability. This project follows previously successful initiatives by the Wheels Task Force in 1998 dealing with the lightweight microalloy steel wheel. The wheel is a 15 x 6 passenger car wheel that is fully competitive with cast aluminum wheels in appearance and weight, offering a weight saving of 27 percent, compared to conventional steel wheels. Additionally, the microalloy steel wheel is up to 11 percent lighter and 18 percent less costly than cast aluminum wheels.
Permanent trim provides attractive styling that is competitive in appearance to aluminum wheels.
Microalloy steel is a high-strength steel in which strength is achieved through additions of alloying elements such as columbium and vanadium. The current full-face steel wheel weighs 29.6 pounds, while the current cast aluminum option wheel weighs 23.3 pounds. A prototype wheel is spun using flow forming technology. In Phase I of the project, the Task Force worked with Hayes-Lemmerz International Inc. to build prototypes using flow forming technology for the rims, a technique never before used for steel rims on light truck wheels. This process involves rotating the rim on a mandrel and using a forming tool, moving metal from one location on the rim to another, which results in variable rim thickness.