Abstract: A thermal barrier coating with unique properties suitable for high temperature thermal insulation control on a substrate is provided. The coating is thermally sprayed, consisting of three layers: 1) a MCrAIY bond coat (basecoat), 2) an intermediate crack resistant ceramic coating, and 3) a top coat of yttria stabilized zirconia. The three layer coating is deposited, preferably, using an air plasma spray system with suitable macro cracks in the top coat, with an underlying crack resistant layer, to enable the ceramic top coat to have properties suitable for advanced gas turbine thermal barrier coatings.

Abstract: A coating application process using a high energy plasma gun utilizing a low amperage and high voltage stabilized arc to deposit coatings with high deposition efficiency (De) and high bond strength under ASTM C 633 Specification.

Abstract: A thermal barrier coating with abradable properties suitable for high temperature clearance control on a sealing surface is provided. The coating is thermally sprayed, consisting of a MCrAlY bond coat and a top coat of yttria stabilized zirconia containing polyester. The two layer coating is deposited using an air plasma spray system with suitable porosity levels to enable the ceramic top coat to have properties suitable for advanced gas turbine shroud block sealing purposes. This coating for sealing purposes is applicable to both industrial and flight gas turbine applications.

Abstract: A strain tolerant ceramic coating, preferably for use as an abrasive coating on a substrate is provided. The coating is prepared from a yttria and zirconia powder having an average particle size less than 40 microns. The coating is formed by depositing the powder on the substrate by a plasma spray process. The as-applied coating contains essentially no macrocracks, but a post-stressed coating contains a random distribution, population, and orientation of microcracks and macrocracks.

Abstract: Known thermal spray apparatus are modified to achieve thermal spray coatings of increased hardness. Thermal spray apparatus operate to develop a plasma stream for introduction to a nozzle, for eventual application to the surface of a substrate. Upon entering the nozzle, the plasma stream is passed through a plasma cooling zone defined by a plasma cooling passageway, to a plasma accelerating zone defined by a narrowed passageway that expands into a plasma/particle confining zone for the discharge of material from the apparatus. The narrowed passageway of the apparatus is cooled, and the powder material to be applied by the apparatus is introduced into the plasma stream along the cooled, narrowed passageway.

Abstract: Known thermal spray apparatus are modified to achieve rough thermal spray coatings. Thermal spray apparatus operate to develop a plasma stream for introduction to a nozzle, for eventual application to the surface of a substrate. Upon entering the nozzle, the plasma stream is passed through a plasma cooling zone defined by a plasma cooling passageway, to a plasma accelerating zone defined by a narrowed passageway that expands into a plasma/particle confining zone for the discharge of material from the apparatus. The narrowed passageway of the apparatus is cooled, and the powder material to be applied by the apparatus is introduced into the plasma stream along the cooled, narrowed passageway.

Abstract: A method for applying a thermal spray coating onto a substrate (24) includes the steps of providing chamber apparatus (10) including a chamber (16) having a gas flow assembly (23) that includes a gas injector (27) and a spray nozzle (30) therein for introducing, a gas and spray coating. The chamber has an adjustably sized restricted opening (18) that is continuously open to the ambient atmosphere (21) that is exterior of the chamber (16). The total gas flow is maintained from the gas flow assembly (23) at a predetermined rate based on the size of the restricted opening (18) and the amount of oxygen that is desired to be present during the spraying of the coating and thereafter until the spray coating solidifies on the substrate. Gas flow from the spray nozzle (30) is determined by optimum process parameters for coating specified materials. If the gas flow from the nozzle (30) is insufficient to provide the total gas flow, the gas injector (27) supplements the total gas flow.