# US 5,705,281 A · Coated nickel-base superalloy article and powder and method useful in its preparation

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,705,281 A
- Document ID: US5705281A
- Status: Granted
- Kind: A
- Application number: 08/561,670
- Filed: 1995-11-22
- Granted: 1998-01-06
- Earliest claimed: 1994-12-28
- Assignees: General Electric Company
- Inventors: Jim D. Reeves; David E. Budinger; Robert A. Anderson
- Web page: https://patentgrep.com/patent/US5705281A

## CPC

- C23C 24/106: {Coating with metal alloys or metal elements only}
- B22F 1/09: {Mixtures of metallic powders}
- B22F 7/062: {involving the connection or repairing of preformed parts}
- B23K 35/0244: {Powders, particles or spheres; Preforms made therefrom}
- B23K 35/025: {Pastes, creams or slurries}
- B23K 35/304: {with Cr as the next major constituent}
- C23C 24/10: with intermediate formation of a liquid phase in the layer
- C23C 26/02: applying molten material to the substrate
- C23C 30/00: Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence)
- Y10T 428/12028: Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, etc.]
- Y10T 428/12063: Nonparticulate metal component
- C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04)
- B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A nickel-base superalloy article has a coating having a composition, in weight percent, of from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, from about 0.001 to about 3 percent boron, from about 1 to about 10 percent silicon, balance nickel and incidental impurities. The coating is preferably applied by mixing together two powders, one with a higher solidus temperature and one with a lower solidus temperature, whose net composition is that of the coating. The powder mixture is compacted with a binder, applied to a surface of the article, and heated to a temperature above the lower solidus temperature.

## Claims

### Claim 1

An article, comprising:
a substrate comprising a nickel-base superalloy having a directionally oriented microstructure; and
a coating on a surface of the substrate, the coating having a composition, in weight percent, consisting essentially of from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, from about 0.001 to about 3 percent boron, from about 1 to about 10 percent silicon, balance nickel and incidental impurities.

### Claim 2 (depends on 1)

The article of claim 1, wherein the coating has a composition of from about 14 to about 16 percent cobalt, from about 19 to about 21 percent chromium, from about 7 to about 8.5 percent aluminum, from about 0.02 to about 0.11 percent yttrium, from 0.001 to about 0.2 percent boron, from about 2.2 to about 2.3 percent silicon, balance nickel.

### Claim 3 (depends on 1)

The article of claim 1, wherein the coating is formed as a product of interdiffusion of
a first alloy precursor comprising from about 10 to about 20 percent cobalt, from about 14 to about percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, balance nickel and incidental impurities, and
second alloy precursor, comprising from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from about 0.001 to about 3 percent boron, from about 2 to about 12 percent silicon, balance nickel and incidental impurities, the first alloy precursor and the second alloy precursor being present in a proportion sufficient to produce the composition of the coating.

### Claim 4 (depends on 3)

The article of claim 3, wherein the first alloy precursor and the second alloy precursor are furnished in the form of prealloyed powders.

### Claim 5 (depends on 1)

The article of claim 1, wherein the substrate is a gas turbine shroud.

### Claim 6

An article, comprising:
a substrate comprising a nickel-base superalloy having a directionally oriented, single-crystal microstructure; and
a coating on a surface of the substrate, the coating having a composition, in weight percent, consisting essentially of from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, from about 0.001 to about 3 percent boron, from about 1 to about 10 percent silicon, balance nickel and incidental impurities.

### Claim 7 (depends on 6)

The article of claim 6, wherein the substrate has a nominal composition of about 7.5 percent cobalt, 7 percent chromium, 6.2 percent aluminum, 0.004 percent boron, 1.5 percent molybdenum, 6.5 percent tantalum, 5 percent tungsten, 0.15 percent hafnium, 0.05 percent carbon, 3 percent rhenium, balance nickel and incidental impurities.

### Claim 8 (depends on 6)

The article of claim 6, wherein the coating has a composition of from about 14 to about 16 percent cobalt, from about 19 to about 21 percent chromium, from about 7 to about 8.5 percent aluminum, from about 0.02 to about 0.11 percent yttrium, from 0.001 to about 0.2 percent boron, from about 2.2 to about 2.5 percent silicon, balance nickel.

### Claim 9 (depends on 6)

The article of claim 6, wherein the coating is formed as a product of interdiffusion of
a first alloy precursor comprising from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, balance nickel and incidental impurities, and
a second alloy precursor, comprising from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent alumina, from about 0.001 to about 3 percent boron, from about 2 to about 12 percent silicon, balance nickel and incidental impurities, the first alloy precursor and the second alloy precursor being present in a proportion sufficient to produce the composition of the coating.

### Claim 10 (depends on 9)

The article of claim 9, wherein the first alloy precursor and the second alloy precursor are furnished in the form of prealloyed powders.

### Claim 11 (depends on 6)

The article of claim 6, wherein the substrate is a gas turbine shroud.

### Claim 12

An article, comprising:
a substrate comprising a nickel-base superalloy having a directionally oriented microstructure, wherein the substrate has a nominal composition of about 7.5 percent cobalt, 7 percent chromium, 6.2 percent aluminum, 0.004 percent boron, 1.5 percent molybdenum, 6.5 percent tantalum, 5 percent tungsten, 0.15 percent hafnium, 0.05 percent carbon, 3 percent rhenium, balance nickel and incidental impurities; and
a coating on a surface of the substrate, the coating having a composition, in weight percent, consisting essentially of from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, from about 0.001 to about 3 percent boron, from about 1 to about 10 percent silicon, balance nickel and incidental impurities.

### Claim 13 (depends on 12)

The article of claim 12, wherein the coating has a composition of from about 14 to about 16 percent cobalt, from about 19 to about 21 percent chromium, from about 7 to about 8.5 percent aluminum, from about 0.02 to about 0.11 percent yttrium, from 0.001 to about 0.2 percent boron, from about 2.2 to about 2.5 percent silicon, balance nickel.

### Claim 14 (depends on 12)

The article of claim 12, wherein the coating is formed as a product of interdiffusion of
a first alloy precursor comprising from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from 0 to about 0.2 percent yttrium, balance nickel and incidental impurities, and
a second alloy precursor, comprising from about 10 to about 20 percent cobalt, from about 14 to about 25 percent chromium, from about 2 to about 12 percent aluminum, from about 0.001 to about 3 percent boron, from about 2 to about 12 percent silicon, balance nickel and incidental impurities, the first alloy precursor and the second alloy precursor being present in a proportion sufficient to produce the composition of the coating.

### Claim 15 (depends on 14)

The article of claim 14, wherein the first alloy precursor and the second alloy precursor are furnished in the form of prealloyed powders.

### Claim 16 (depends on 12)

The article of claim 12, wherein the substrate is a gas turbine shroud.