Combustion-synthesis process for making friction materials

Claim 1

A self-propagating, aluminothermic process for producing a friction material, comprising the steps of sequentially: (a) providing a composition comprised of a mixture of aluminum, iron, and at least one metal oxide, wherein: 1. said metal oxide is selected from the group consisting of the oxides of iron, copper, chromium, nickel, molybdenum, cobalt, manganese, lead, tin, silicon, bismuth, aluminum, and mixtures thereof; 2. at least 80 weight percent of said composition is comprised of said mixture of said aluminum, said iron, and said metal oxide(s); 3. said aluminum and said iron comprise from about 20 to about 80 weight percent of said mixture; 4. said metal oxide(s) comprise from about 80 to about 15 weight percent of said mixture; 5. the weight of said aluminum in said mixture represents from about 5 to about 35 weight percent of the combined weight of aluminum and iron in the mixture; and 6. the weight of said iron in said mixture represents from about 65 to about 95 weight percent of the combined weight of the aluminum and iron in the mixture; (b) forming said composition into a green body; (c) preheating said green body to a temperature of from about 50 to about 400 degrees centigrade; (d) igniting said preheating green body by contacting it with a heat source at a temperature of at least about 700 degrees centigrade; and (e) reacting said aluminum with said metal oxide(s), thereby densifying said green body.