STTR Phase I: Direction and Profile Control for Thermal Sprays

This Small Business Technology Transfer (STTR) Phase I project aims to apply the unique property of high-speed jets to adhere to nearby curved surfaces, with a turning radius much larger than the size of the jet - the so-called COANDA effect. The proposed research aims to take advantage of this effect to manipulate thermal spray jet stream and vector the stream such that the hot thermal gas stream can be effectively bent away from the surface to be coated while allowing the heated powders to strike the surface to product the coating. The benefit of this approach is in being able to maintain the substrate at a temperature that allows a hard coating to be applied to the surface without excessively heating the part. This would allow the process to be applied to a wide variety of thermally sensitive substrate materials. Other advantages include improved stability of thermal sprays, better control of the coating process and ability to operate in confined spaces and harsh environments. The broader impacts of this technology, if successful, will be in the $3.5 billion thermal spray coating market, which serves a wide range of critical applications, including aerospace components, from landing gears, engine hot-section parts and other components subjected to hot corrosion and thermo-mechanical degradation in service; automotive components, medical implants, electronics. The ability to manipulate thermal jets will be further enhanced by the addition of robotic controls that allow coating of intricate parts, confined environments and improved spray coatings.