Chromizing over cathodic arc coating

Patent metadata

Field	Value
Publication number	US-2016298231-A1
Application number	US-201415103761-A
Country	US
Kind code	A1
Filing date	Nov 19, 2014
Priority date	Dec 10, 2013
Publication date	Oct 13, 2016
Grant date	—

Abstract

The present invention provides a Cr-rich cathodic arc coating, an article in turbine blade coated with the chromizing over cathodic arc coating, and a method to produce the coating thereof. The Cr-rich cathodic arc coating in the present invention comprises a cathodic arc coating and a diffusion coating deposited atop the cathodic arc coating to enforce hot corrosion resistance. The hardware coated with the chromizing over cathodic arc coating in the present invention is reinforced with superior—hot corrosion resistance. The present invention further provides a novel method for producing the chromizing over cathodic arc coating by re-sequencing coating deposition order. The method in the present invention is efficient and cost-reducing by eliminating some operations, e.g., DHT and peening, between the cathodic arc coating and the diffusion coating. The hot corrosion resistance in the present invention results from the high Cr content in the surface of the coating.

First claim

1 . A chromium-rich cathodic arc coating comprising;
a MCrAlY on a substrate, wherein M is a metal alloy comprising nickel, cobalt, iron, or a combination thereof; and a diffused chromide coating atop the MCrAlY, wherein a surface of the diffused chromide coating has high content of chromium.

2 . The chromium-rich cathodic arc coating according to claim 1 , wherein the surface of the diffused chromide coating atop the MCrAlY contains chromium content from about 20% to about 50% by weight.

3 . The chromium-rich cathodic arc coating according to claim 2 , wherein the MCrAlY contains chromium content between about 25% and 35% by weight based on the weight of the MCrAlY.

4 . The chromium-rich cathodic arc coating according to claim 1 , wherein the MCrAlY comprises nickel, cobalt, iron, chromium, aluminum, hafnium, yttrium, or a combination thereof.

5 . The chromium-rich cathodic arc coating according to claim 1 , wherein the diffused chromide coating comprises a chromium rich phase.

6 . The chromium-rich cathodic arc coating according to claim 1 , wherein the chromium-rich cathodic arc coating is resistant to hot corrosion at a temperature between about 1200° F. and 1600° F.

7 . The chromium-rich cathodic arc coating according to claim 1 , wherein the chromium-rich cathodic arc coating is resistant to stress corrosion.

8 . The chromium-rich cathodic arc coating according to claim 1 , wherein the chromium-rich cathodic arc coating is resistant to low cycle fatigue.

9 . The chromium-rich cathodic arc coating according to claim 1 , wherein the substrate comprises a blade root, internal surface of turbine blade, or the external surface of a turbine blade.

10 . An article comprising:
a) a substrate; b) a MCrAlY on a substrate, wherein M is a metal alloy comprising nickel, cobalt, iron, or a combination thereof; and c) a diffused chromide coating atop the MCrAlY; wherein a surface of the diffused chromide coating atop the MCrAlY has high content of chromium.

11 . The article according to claim 4410 , wherein the substrate comprises a blade root, internal surface of turbine blade, or the external surface of a turbine blade.

12 . The article comprising according to claim 10 , wherein the MCrAlY comprises nickel, cobalt, iron, chromium, aluminum, hafnium, yttrium, or a combination thereof.

13 . The article comprising according to claim 10 , wherein the diffused chromide coating comprises a chromium rich phase.

14 . A method of producing a chromium-rich cathodic arc coating comprising steps of:
a) applying a MCrAlY on a substrate, wherein M is a metal alloy comprising nickel, cobalt, iron, or a combination thereof; and b) applying a diffused chromide coating atop the MCrAlY;
wherein a surface of the diffused chromide coating atop the MCrAlY has high content of chromium.

15 . The method of claim 14 , wherein the diffused chromide coating contains chromium content from about 20% to about 50% by weight.

16 . The method of claim 15 , wherein the MCrAlY contains chromium content of between about 25% and 35% by weight based on the weight of the MCrAlY.

17 . The method of claim 14 , wherein the MCrAlY comprises nickel, cobalt, iron, chromium, aluminum, hafnium, yttrium, or a combination thereof.

18 . The method of claim 14 , wherein the diffused chromide coating comprises a chromium rich phase.

19 . The method of claim 14 , wherein the method of applying the MCrAlY comprises cathodic arc deposition.

20 . The method of claim 14 , wherein the method of applying the diffused chromide coating atop the MCrAlY comprises pack chromizing, slurry chromizing, vapor diffusion coating, or gas diffusion coating.

Assignees

• United Technologies Corp

Inventors

• Trzcinski Frank J
• Balzano Thomas
• Sinesi Prentice M
• Livings Mark A
• Task Michael N

Classifications

• F01D5/28

  Selecting particular materials; {Particular measures relating thereto;} Measures against erosion or corrosion · CPC title

• F05D2300/611

  Coating · CPC title

• Y10T428/12979

  Containing more than 10% nonferrous elements [e.g., high alloy, stainless] · CPC title

• C23C10/20

  only one element being diffused · CPC title

• B32B15/043

  of metal (B32B15/01 takes precedence) · CPC title