Tokyo, 28 August 1998. In its on-going quest to produce ecologically softer technology and products, Mitsubishi Motors announces the development of lead-free coated steel sheet for use in fuel tanks, thereby eliminating potential environment impact problems associated with the toxic metal.

Automobile fuel tanks are conventionally made using terne metal, which is steel sheet that has been coated with a lead-tin alloy in a hot-dip process. The new materials developed by Mitsubishi Motors to ameliorate environmental impact are hot dip galvanized steel sheet with lead-free surface treatment.

The lead-free material developed jointly with Kawasaki Steel Corporation and announced in 1997, uses galvannealed steel sheet with an organic coating. The latest material, developed with the assistance of Nippon Steel Corporation, uses hot dip galvanized steel sheet with a nickel-flash plating.

These two types of lead-free coated steel sheet offer superior performance, both in terms of cost and corrosion resistance. They also have the merit of not requiring the installation of any new processing equipment since they can be press-formed and seam welded in the same way as terne-coated steel.

Because both the nickel-plated and the organic-coated sheet employ the same hot dip galvanized steel base, the two materials can be used alongside each other. Ordering lead-free treated galvannealed steel sheet from both Kawasaki Steel and Nippon Steel provides Mitsubishi Motors with benefits in terms of delivery and technical support. The company will first use a fuel tank made from the new materials in a new model due to be launched this autumn.