General Electric Company

William B Connor

Jon Conrad Schaeffer

Bangalore Aswatha Nagaraj

David John Wortman

Robert D Field

Robert William Bruce

Larry W Plemmons

Himanshu B Vakil

Mark Alan Rosenzweig

Wendy Howard Murphy

Richard William Jendrix

Jon C Schaffer

A thermal barrier coating system and a method for forming the coating system which yields a thermal barrier coating having good adhesion to a bond coat overlying a metal superalloy substrate. The adhesion of the bond coat and the thermal barrier coating is enhanced by forming a mature .alpha.-alumina (Al.sub.2 O.sub.3) scale at the bond coat-TBC interface. The desired mature .alpha.-alumina scale can be obtained by utilizing one or more of the following steps: preoxidation of the bond coat at certain minimum temperatures and durations; inoculation of the surface of the bond coat; surface doping or alloying of the bond coat surface; and the addition of noble metals to the bond coat. Each of these steps promotes the formation of .alpha.-alumina and avoids the formation of the .gamma., .delta. and .theta.-alumina phases which undergo phase transformations at elevated temperatures, with the result that a more spallation-resistant thermal barrier coating system is obtained.

Method for forming a thermal barrier coating

A method for manufacturing an article for use in a gas tubine engine is disclosed, which comprises applying a metallic bond coating on a superalloy substrate; surface doping a surface of the bond coating with at least one element selected from the group consisting of Fe, Cr and Y by plating, ion implantation, MOCVD and sputttering; and then applying an insulative ceramic coating on the bond coating.

Method for manufacturing thermal barrier coated articles

A bond-coated substrate is protected with an alpha alumina layer. The alpha alumina layer may be deposited as a relatively thick layer directly onto the bond-coated substrate. In this embodiment, no further ceramic layer overlies the alpha alumina layer. Other ceramics may be mixed into the alpha alumina layer, however. In another embodiment, a layer of a ceramic other than alpha alumina is deposited over the bond-coated substrate, and an alpha alumina layer is deposited over the ceramic layer.

Alpha alumina protective coatings for bond-coated substrates and their

A coated article is prepared by melting and casting an article substrate formed of a nickel-base superalloy. The article substrate is heated in a hydrogen-containing atmosphere at a temperature of at least 2000.degree. F. for a period sufficient to desulfurize the substrate to a sulfur content of less than about 1 part per million. Optionally, an aluminum-oxide environmental coating is provided overlying the substrate. A ceramic thermal barrier coating is applied overlying the substrate. Significantly, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.

Thermal barrier coating system having no bond coat

A coated article comprises a base article having a substrate made of a material selected from the group consisting of a nickel-base alloy and a cobalt-base alloy, an intermediate metallic coating structure, and a thermal barrier coating. The intermediate metallic coating structure may be a protective layer of platinum, rhodium, or palladium on the base article, with no bond coat. The intermediate metallic coating may also be a bond coat, either oxidized or unoxidized, with a protective layer of platinum, rhodium, or palladium thereon. The protective layer typically partially interdiffuses with the underlying metallic structure.

Growing community of inventors

Clifton Park, NY, United States of America

William B Connor