Innovative Surface Modifications to Promote Wear Resistance

Nitrided and/or carburized surface cases on light metals such as aluminum, magnesium, titanium, and their alloys, economically formed, would allow significant weight reduction in equipment from a simple machine to an advanced engine. Such cased material could replace steel gears, crankshafts, pinions, and other parts requiring wear resistance. The net result would be more fuel efficient, less costly industrial and consumer activities. A majority of work in forming such coatings requires ion nitriding, laser processing, plasma technology, and even surface melting and resolidification. All these methods are difficult and capital intensive processing. This project will look at a simpler, more cost effective approach: gas nitriding and/or carburizing in a fluidized bed furnace. To do this, a suitable gas composition and time must be identified. Decomposition products of candidate gas mixtures will be considered to ascertain the required off-gas handling requirements to prevent adverse environmental impacts. Then, some example cases will be made and characterized with respect to chemistry and physical properties.