Thermal Barrier System with Thin Dense Columnar TBC Layer and Methods of Forming the Same

Patent metadata

Field	Value
Publication number	US-2018290929-A1
Application number	US-201715481550-A
Country	US
Kind code	A1
Filing date	Apr 7, 2017
Priority date	Apr 7, 2017
Publication date	Oct 11, 2018
Grant date	—

Abstract

A coating system disposed on a surface of a substrate is provided. The coating system may include a bond coating layer on the surface of the substrate, a dense TBC layer on the bond coating layer, and a columnar TBC layer on the dense TBC layer, with the columnar TBC layer defines a plurality of elongated surface-connected voids. The dense TBC layer generally includes a ceramic material and has a porosity of about 15% or less. A method is also provided for forming a coating system on a surface of a substrate.

First claim

What is claimed is:

1 . A coating system disposed on a surface of a substrate, the coating system comprising:
a bond coating layer on the surface of the substrate; a dense TBC layer on the bond coating layer, wherein the dense TBC layer comprises a ceramic material, and wherein the dense TBC layer has a porosity of about 15% or less; and a columnar TBC layer on the dense TBC layer, wherein the columnar TBC layer defines a plurality of elongated surface-connected voids.

2 . The coating system as in claim 1 , wherein the ceramic material comprises hafnium oxide, zirconium oxide, or a mixture thereof.

3 . The coating system as in claim 1 , wherein the ceramic material comprises a stabilized hafnium oxide, a stabilized zirconium oxide, or a mixture thereof.

4 . The coating system as in claim 1 , wherein the ceramic material comprises a yttria-stabilized zirconia, a ceria-stabilized zirconia, a calcia-stabilized zirconia, a scandia-stabilized zirconia, a magnesia-stabilized zirconia, an india-stabilized zirconia, an ytterbia-stabilized zirconia, a lanthana-stabilized zirconia, a gadolinia-stabilized zirconia, or a mixture thereof.

5 . The coating system as in claim 1 , wherein the columnar TBC layer has a thickness of about 25 microns to about 2000 microns.

6 . The coating system as in claim 5 , wherein the dense TBC layer has a thickness that is about half of the thickness of the columnar TBC layer, or less.

7 . The coating system as in claim 5 , wherein the dense TBC layer has a thickness that is about ¼ th to about ⅛ th of the thickness of the columnar TBC layer.

8 . The coating system as in claim 1 , wherein the dense TBC layer has a porosity of about 0.1% to about 10%.

9 . The coating system as in claim 1 , further comprising:
a thermally grown oxide on the bond coating layer, wherein the thermally grown oxide is positioned between the bond coating layer and the dense TBC layer.

10 . The coating system as in claim 1 , further comprising:
an intermediate dense layer positioned between the dense TBC layer and the columnar TBC layer.

11 . The coating system as in claim 10 , wherein the intermediate dense layer is a gadolinium-containing intermediate dense layer.

12 . The coating system as in claim 10 , wherein the intermediate dense layer has a porosity that is about 15% or less.

13 . The coating system as in claim 10 , wherein the intermediate dense layer has a thickness that is about half of the thickness of the columnar TBC layer, or less.

14 . The coating system as in claim 10 , wherein the intermediate dense layer has a thickness that is about ¼ th to about ⅛ th of the thickness of the columnar TBC layer.

15 . The coating system as in claim 10 , wherein the intermediate dense layer has a porosity of about 0.1% to about 10%.

16 . The coating system as in claim 1 , further comprising:
an outer dense TBC layer on the columnar TBC layer; and an outer columnar TBC layer on the outer dense TBC layer.

17 . A method of forming a coating system on a surface of a substrate, the method comprising:
forming a dense TBC layer on a bond coating layer overlying a substrate, wherein the dense TBC layer comprises a ceramic material, and wherein the dense TBC layer is formed to a porosity of about 15% or less; and applying a columnar TBC layer on the dense TBC layer such that the columnar TBC layer defines a plurality of elongated surface-connected voids.

18 . The method as in claim 17 , wherein forming the dense TBC layer comprises:
applying the ceramic material onto the bond coating layer to have an initial porosity; and backfilling the ceramic material applied on the bond coating layer to increase the density to form the dense TBC layer.

19 . The method as in claim 17 , further comprising:
forming an intermediate dense layer on the dense TBC layer prior to forming the columnar TBC layer.

20 . The method as in claim 19 , wherein the intermediate dense layer is a gadolinium-containing intermediate dense layer.

Assignees

• Gen Electric

Inventors

• Clark Michael David
• Konitzer Douglas Gerard

Classifications

• C23C4/134 Primary

  Plasma spraying · CPC title

• C23C4/11

  Oxides · CPC title

• C23C14/08

  Oxides (C23C14/10 takes precedence) · CPC title

• C23C28/048

  with layers graded in composition or physical properties · CPC title

• C23C14/58

  After-treatment · CPC title