Development and Testing of Non-Asbestos Brake Lining Materials for Off-Highway Machines

There is considerable controversy over the use of asbestos in the automotive industry. Various proposed government regulations, including EPA's recent proposal of an eventual ban on the use of asbestos in friction products, have added to the controversy. These proposals could affect the efforts of both the off-highway and on-highway segments of the automotive industry to find suitable alternatives for asbestos used in brake linings. The industry - including Rockwell International - shares the health concerns voiced by many relative to long term exposure to asbestos fibers. Not to be overlooked, however, is the potential for increased safety related problems involving the performance or durability of alternative materials not adequately developed and tested on brakes in the laboratory and on vehicles in the field. In this regard, moving ahead cautiously is required.

The purpose of this paper is to (a) briefly describe current issues relating to the use of asbestos friction products in the United States, (b) describe the challenges that lining and brake manufacturers face in the elimination of asbestos in friction materials, and (c) provide data showing the progress made in satisfying design and performance parameters necessary to give the required vehicle braking performance.