Session *BB3.2

9:00 AM *BB3.2
KINETIC SPRAY COATINGS. John R. Smith, Thomas H. Vansteenkiste, Richard E. Teets, and Jerome J. Moleski, General Motors R&D Center, Warren, MI.

Coatings can now be made from powders via a high-velocity spray technique without the requirement of melting or thermally softening the powders prior to impingement onto the substrate. Not only is the process simplified by not requiring arcs, flames, or plasmas, but also desireable coating properties such as low oxide content and low thermal stress can be obtained. In this process the powders are entrained in a gas, which is usually air, and accelerated through a nozzle. Mechanisms by which this kinetic energy source can yield good coatings will be discussed. The optimization of coating properties by variation of process parameters in our new coating apparatus will also be described for coatings including elements such as Cu, Al, and Fe.