EP0272197A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Silicon carbide abrasive particles having multilayered coating
Assignee: RTX Corp
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Filing: 1987-12-14
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Granted: —
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Expires: 2007-12-14
Abstract
Abstract Ceramic particles (18) useful as abrasives in a metal matrix layer are described. The particles are coated with an oxide monolayer (30) and a metal duplex layer. Preferably, the particles are silicon carbide; the oxide monolayer is aluminum oxide, and the metal duplex layer is a nickel-boron alloy (32) over pure nickel (31).
Inventors
- 👤 David Arthur Condit
- 👤 Harry Edwin Eaton
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 03:07
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; B; B22; B22F; B22F1/00; B22F1/18; C04B41/45; C04B41/4584; C04B41/52; C04B41/80; C04B41/81; C04B41/89; C09; C09K; C09K3/00; C09K3/14; C09K3/1436; C23; C23C; C23C18/00; C23C18/16; C23C18/1601; C23C18/1633; C23C18/1646; C23C18/165; C23C18/1651; C23C18/1689; C23C18/1692; C23C18/31; C23C18/32; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12063; Y10T428/12181
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
96 words
Metal coated ceramic abrasive particles in the range of about 25 to 1,250 microns, the particles having a duplex metal coating thereon which comprises a first metal coating layer which substantially encapsulates each particle and a second metal coating layer which substantially encapsulates the first coating layer, wherein the second metal layer is capable of significant diffusion into nickel and cobalt base superalloys when heated near its melting temperature and forms no deleterious phases on diffusing into said superalloys, and the second metal layer wets the first metal layer when the second metal layer is molten.
Claim 2
Dependent Claim
96 words
Metal coated ceramic abrasive particles in the range of about 25 to 1,250 microns, the particles having a duplex metal coating thereon which comprises a first metal coating layer which substantially encapsulates each particle and a second metal coating layer which substantially encapsulates the first coating layer, wherein the second metal layer is capable of significant diffusion into nickel and cobalt base superalloys when heated near its melting temperature and forms no deleterious phases on diffusing into said superalloys, and the second metal layer wets the first metal layer when the second metal layer is molten.
Claim 3
Dependent Claim
89 words
The particles of claim l, wherein the ceramic is selected from the group consisting essentially of silicon carbide, silicon nitride, and SiAlON; the first metal layer is selected from the transition metals, high melting temperature noble metals, and alloys thereof; and the second metal layer is selected from said transition and noble metals and alloys thereof which contain a melting point depressant in sufficient quantity so that the second metal layer melts at a temperature at least about 150°C less than the melting temperature of the first metal layer.
Claim 4
Dependent Claim
35 words
The particles of claim 2, wherein the ceramic is silicon carbide, the first metal layer is nickel and the second metal layer is a nickel-boron alloy containing between about 1 and 5% boron by weight.
Claim 5
Dependent Claim
20 words
The particles of claim 3, further comprising a layer of aluminum oxide between the silicon carbide and the nickel layer.
Claim 6
Dependent Claim
111 words
A ceramic useful as a dispersoid in metal matrices at high service temperatures and having a multiple layer coating thereon which comprises an oxide coating layer resistant to diffusion or dissolution with the ceramic at said service temperatures; and a duplex metal coating layer over the oxide coating layer, the duplex metal coating layer comprising first and second metal layers, the first metal layer having a melting temperature above said service temperatures, and resistant to diffusion or dissolution with the oxide coating layer at said service temperatures, and the second metal layer having a melting temperature less than about 1,100°C, said second metal layer wetting the first metal layer when molten.
Claim 7
Dependent Claim
111 words
A ceramic useful as a dispersoid in metal matrices at high service temperatures and having a multiple layer coating thereon which comprises an oxide coating layer resistant to diffusion or dissolution with the ceramic at said service temperatures; and a duplex metal coating layer over the oxide coating layer, the duplex metal coating layer comprising first and second metal layers, the first metal layer having a melting temperature above said service temperatures, and resistant to diffusion or dissolution with the oxide coating layer at said service temperatures, and the second metal layer having a melting temperature less than about 1,100°C, said second metal layer wetting the first metal layer when molten.
Claim 8
Dependent Claim
85 words
The ceramic of claim 5, useful as a dispersoid in matrices used at service temperatures above about 815°C, wherein the oxide coating layer is resistant to diffusion or dissolution with the ceramic at temperatures up to at least about 1,100°C; the first metal layer being resistant to diffusion or dissolution with the oxide layer at temperatures up to at least about 1,100°C; and the second metal layer having a melting temperature at least about 150°C lower than the melting temperature of the first metal layer.
Claim 9
Dependent Claim
70 words
Ceramic particles useful as a dispersoid in metal matrices at high temperatures, the particles having a size within the range of about 25-1,250 microns and having a multiple layer metal coating thereon which comprises a first metal layer having a melting temperature of at least about 1,315°C; and a second metal layer having a melting point less than about 1,100°C and capable of wetting the first metal layer when molten.
Claim 10
Dependent Claim
70 words
Ceramic particles useful as a dispersoid in metal matrices at high temperatures, the particles having a size within the range of about 25-1,250 microns and having a multiple layer metal coating thereon which comprises a first metal layer having a melting temperature of at least about 1,315°C; and a second metal layer having a melting point less than about 1,100°C and capable of wetting the first metal layer when molten.
Claim 11
Dependent Claim
54 words
Silicon carbide particles having a size in the range of about 25-1,250 microns, and having a 5-25 micron thick layer of aluminum oxide, a 2-8 micron layer of nickel over the aluminum oxide coating, and a 2-8 micron layer of nickel-boron over the nickel coating, the nickel-boron coating containing between 1-5 weight percent boron.
Claim 12
Dependent Claim
54 words
Silicon carbide particles having a size in the range of about 25-1,250 microns, and having a 5-25 micron thick layer of aluminum oxide, a 2-8 micron layer of nickel over the aluminum oxide coating, and a 2-8 micron layer of nickel-boron over the nickel coating, the nickel-boron coating containing between 1-5 weight percent boron.
Claim 13
Independent Claim
189 words
A method for providing an abrasive layer containing ceramic particles in a metal matrix on the surface of an article, comprising the steps of adhering a single layer of the particles in spaced apart relation onto the article surface, the particles having a multiple layer coating thereon which comprises a first oxide coating layer resistant to diffusion or dissolution with the particles at temperatures above about 1,100°C, and a duplex metal coating layer which comprises first and second metal layers, the first metal layer having a melting temperature above about 1,315°C and resistant to diffusion or dissolution with the oxide layer at temperatures above about 1,100°C, and the second metal layer having a melting point less than about 1,100°C and capable of wetting the first metal layer when molten; causing the coated particles to adhere to the article surface and to project from the surface in spaced apart relation; depositing on the article surface and over the particles a layer of metal matrix material to fill in the spaces between the coated particles; and treating the surface of the matrix so that the particles project above the matrix surface.
Claim 14
Independent Claim
189 words
A method for providing an abrasive layer containing ceramic particles in a metal matrix on the surface of an article, comprising the steps of adhering a single layer of the particles in spaced apart relation onto the article surface, the particles having a multiple layer coating thereon which comprises a first oxide coating layer resistant to diffusion or dissolution with the particles at temperatures above about 1,100°C, and a duplex metal coating layer which comprises first and second metal layers, the first metal layer having a melting temperature above about 1,315°C and resistant to diffusion or dissolution with the oxide layer at temperatures above about 1,100°C, and the second metal layer having a melting point less than about 1,100°C and capable of wetting the first metal layer when molten; causing the coated particles to adhere to the article surface and to project from the surface in spaced apart relation; depositing on the article surface and over the particles a layer of metal matrix material to fill in the spaces between the coated particles; and treating the surface of the matrix so that the particles project above the matrix surface.
Claim 15
Dependent Claim
111 words
An abrasive layer on the tip surface of a gas turbine engine blade, the layer containing spaced apart ceramic particles in a metal matrix, wherein the ceramic particles are each sinter bonded to the blade surface and the matrix fills in the regions between the particles, wherein each particle has an oxide monolayer and a duplex metal coating layer thereon, wherein the oxide monolayer does not react with the ceramic and substantially encapsulates each particle; and the duplex metal coating layer comprises first and second metal layers, the first metal layer not reacting with the ceramic and substantially encapsulating each particle, and the second metal layer diffused with the blade surface.
Claim 16
Dependent Claim
111 words
An abrasive layer on the tip surface of a gas turbine engine blade, the layer containing spaced apart ceramic particles in a metal matrix, wherein the ceramic particles are each sinter bonded to the blade surface and the matrix fills in the regions between the particles, wherein each particle has an oxide monolayer and a duplex metal coating layer thereon, wherein the oxide monolayer does not react with the ceramic and substantially encapsulates each particle; and the duplex metal coating layer comprises first and second metal layers, the first metal layer not reacting with the ceramic and substantially encapsulating each particle, and the second metal layer diffused with the blade surface.
Claim 17
Dependent Claim
33 words
The abrasive layer of claim 10, wherein the ceramic is silicon carbide, the oxide layer is aluminum oxide, the first metal layer is nickel and the second metal layer is a nickel-boron alloy.
References Cited (Backward Citations)
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