摘要:
A process for depositing coatings, and particularly erosion-resistant coatings suitable for protecting surfaces subjected to collisions with particles, such as a compressor blade of a gas turbine engine. The blade has an airfoil comprising oppositely-disposed convex and concave surfaces, oppositely-disposed leading and trailing edges defining therebetween a chord length of the airfoil, and a blade tip. An erosion-resistant coating is present on at least the concave surface, but not on the convex surface within at least 20% of the chord length from the leading edge.
摘要:
A high emissivity (Hi-E) coating for use on the exhaust baffles of HIRSS systems. HIRSS systems were developed to reduce the infrared (IR) signature of helicopter engines. Increasing operating temperatures of helicopter engines have made the HIRSS systems less effective. An infrared coating applied over selected portions of the HIRSS reduces the IR of the system. The Hi-E coating comprises, in weight percent, 30-80% refractory oxide pigment, 5-20% binder, 1-15% potassium oxide, optionally up to about 15% glass-forming material and the balance refractory oxide powder. When applied to provide a surface finish of 1100Ra microinches or coarser, the coated HIRSS has a significantly reduced hemispherical reflectance in the IR frequency range.
摘要:
An anti-stick coating that inhibits the adhesion of contaminants that form deposits on the internal cooling passages of gas turbine engine components. The anti-stick coating is formed as an outer coating of the internal cooling passages, and preferably overlies an environmental coating such as a diffusion aluminide coating formed on the passage surfaces. The outer coating has a thickness of not greater than three micrometers, and is resistant to adhesion by dirt contaminants as a result of comprising at least one layer of tantala, titania, hafnia, niobium oxide, yttria, silica and/or alumina. The outer coating is preferably deposited directly on the environmental coating by chemical vapor deposition.