THERMAL BARRIER COATING AND METHOD OF DEPOSITING THE SAME ON COMBUSTION CHAMBER COMPONENT SURFACES

摘要

A thermal barrier coating and method of depositing the same on the surfaces of combustion chamber components in compression-ignition internal combustion engines is disclosed. The thermal barrier coating is a dual layer having a first metallic layer comprised of MCrAlY material deposited on the component surface. A porous ceramic layer comprised of Yttria partially stabilized zirconia or Ceria-Yttria partially stabilized zirconia is deposited on the metallic layer to impede the flow of heat therethrough. In operation, the metallic layer creates a mechanical bond between the component surface and the ceramic layer, allows for a smooth transition between the differing physical properties of the component and the ceramic layer and serves as a corrosion barrier by protecting the component from combustion gases and contaminants. There is further disclosed a method of depositing the thermal barrier coating comprising the steps of (1) chemically treating the component surface to remove dirt and oil; (2) grit blasting the treated component surface to roughen the surface and increase the available surface area for deposition; (3) plasma spray depositing a metallic layer comprised of MCrAlY material on the roughened component surface to a thickness between 0.003-0.006 inches; and (4) depositing a porous ceramic material comprised of 10 %-15 % volume porosity Yttria partially stabilized zirconia or 10 %-15 % volume porosity Ceria-Yttria partially stabilized zirconia on the metallic layer to impede the flow of heat therethrough.