Thin 7YSZ, interfacial layer as cyclic durability (spallation) life enhancement for low conductivity tbcs

Abstract

A spallation resistant metallic article comprising a metallic substrate, at least one ceramic thermal barrier coating comprising a zirconia base and at least one other element selected from the group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, In, Y, Mo and C, rare earth oxides, scandium, and indium, and a ceramic bond coat located on at least a portion of the substrate and between the metallic substrate and the at least one ceramic thermal barrier coating wherein the ceramic bond coat is composed of yttria stabilized zirconia (YSZ).

Description

technical field [0001] The invention relates to a ceramic material for thermal insulating coatings applied to metal parts, wherein an interfacial layer of stabilized zirconia is inserted between the part and the coating. Background technique [0002] Gas turbine engines are very well developed mechanical devices that convert chemical potential energy in the form of fuel into thermal energy and then into mechanical energy for propelling aircraft, generating electricity, pumping fluids, etc. At present, the main feasible way to improve the efficiency of gas turbine engines appears to be to use higher operating temperatures. However, metallic materials currently used in gas turbine engines are very close to the upper limit of their thermal stability. In the hottest parts of modern gas turbine engines, metallic materials are used at gas temperatures above their melting points. They are maintained thanks to air cooling. However, providing air cooling reduces engine efficiency....

AI Technical Summary

Problems solved by technology

[0006] However, although Gd-Zr based TBC especially 59wt%Gd 2 o 3 -41 ZrO 2 , has a relatively low thermal conductivity coefficient, but still requires TBC to have lower thermal conductivity properties

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