GB2136720A - Joining silicon nitride to metals - Google Patents
Joining silicon nitride to metals Download PDFInfo
- Publication number
- GB2136720A GB2136720A GB8330304A GB8330304A GB2136720A GB 2136720 A GB2136720 A GB 2136720A GB 8330304 A GB8330304 A GB 8330304A GB 8330304 A GB8330304 A GB 8330304A GB 2136720 A GB2136720 A GB 2136720A
- Authority
- GB
- United Kingdom
- Prior art keywords
- metal
- silicon nitride
- thermal expansion
- layer
- metal alloy
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B37/00—Joining burned ceramic articles with other burned ceramic articles or other articles by heating
- C04B37/02—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles
- C04B37/023—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles characterised by the interlayer used
- C04B37/025—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles characterised by the interlayer used consisting of glass or ceramic material
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B37/00—Joining burned ceramic articles with other burned ceramic articles or other articles by heating
- C04B37/02—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles
- C04B37/023—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles characterised by the interlayer used
- C04B37/026—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles characterised by the interlayer used consisting of metals or metal salts
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/28—Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
- F01D5/284—Selection of ceramic materials
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/0015—Multi-part pistons
- F02F3/003—Multi-part pistons the parts being connected by casting, brazing, welding or clamping
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/10—Pistons having surface coverings
- F02F3/12—Pistons having surface coverings on piston heads
- F02F3/14—Pistons having surface coverings on piston heads within combustion chambers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F7/00—Casings, e.g. crankcases or frames
- F02F7/0085—Materials for constructing engines or their parts
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F7/00—Casings, e.g. crankcases or frames
- F02F7/0085—Materials for constructing engines or their parts
- F02F7/0087—Ceramic materials
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/02—Aspects relating to interlayers, e.g. used to join ceramic articles with other articles by heating
- C04B2237/04—Ceramic interlayers
- C04B2237/06—Oxidic interlayers
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/02—Aspects relating to interlayers, e.g. used to join ceramic articles with other articles by heating
- C04B2237/04—Ceramic interlayers
- C04B2237/06—Oxidic interlayers
- C04B2237/062—Oxidic interlayers based on silica or silicates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/02—Aspects relating to interlayers, e.g. used to join ceramic articles with other articles by heating
- C04B2237/04—Ceramic interlayers
- C04B2237/06—Oxidic interlayers
- C04B2237/064—Oxidic interlayers based on alumina or aluminates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/02—Aspects relating to interlayers, e.g. used to join ceramic articles with other articles by heating
- C04B2237/12—Metallic interlayers
- C04B2237/121—Metallic interlayers based on aluminium
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
- C04B2237/32—Ceramic
- C04B2237/36—Non-oxidic
- C04B2237/368—Silicon nitride
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
- C04B2237/40—Metallic
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
- C04B2237/40—Metallic
- C04B2237/402—Aluminium
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
- C04B2237/40—Metallic
- C04B2237/405—Iron metal group, e.g. Co or Ni
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
- C04B2237/40—Metallic
- C04B2237/405—Iron metal group, e.g. Co or Ni
- C04B2237/406—Iron, e.g. steel
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
- C04B2237/58—Forming a gradient in composition or in properties across the laminate or the joined articles
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
- C04B2237/64—Forming laminates or joined articles comprising grooves or cuts
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
- C04B2237/74—Forming laminates or joined articles comprising at least two different interlayers separated by a substrate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
- C04B2237/76—Forming laminates or joined articles comprising at least one member in the form other than a sheet or disc, e.g. two tubes or a tube and a sheet or disc
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
- C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
- C04B2237/84—Joining of a first substrate with a second substrate at least partially inside the first substrate, where the bonding area is at the inside of the first substrate, e.g. one tube inside another tube
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/0015—Multi-part pistons
- F02F3/003—Multi-part pistons the parts being connected by casting, brazing, welding or clamping
- F02F2003/0061—Multi-part pistons the parts being connected by casting, brazing, welding or clamping by welding
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2300/00—Materials; Properties thereof
- F05D2300/10—Metals, alloys or intermetallic compounds
- F05D2300/12—Light metals
- F05D2300/121—Aluminium
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2300/00—Materials; Properties thereof
- F05D2300/20—Oxide or non-oxide ceramics
- F05D2300/22—Non-oxide ceramics
- F05D2300/228—Nitrides
- F05D2300/2283—Nitrides of silicon
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2300/00—Materials; Properties thereof
- F05D2300/50—Intrinsic material properties or characteristics
- F05D2300/502—Thermal properties
- F05D2300/5021—Expansivity
Abstract
The problem of joining silicon nitride to a metal or metal alloy is overcome by bonding a surface of the silicon nitride to a layer of aluminium oxide or an aluminium silicon compound or magnesia or magnesium oxide or mullite, then bonding that first layer to a layer of nickel alumina before joining the nickel alumina to the metal or metal alloy by a conventional brazing or welding process. This has the further advantage of accommodating the widely differing coefficients of thermal expansion between the silicon nitride and the metal by the provision of materials between them which have graded coefficients of thermal expansion between the two extreme coefficients of thermal expansion. The method can be used to produce pistons having silicon nitride crown portions joined to aluminium or aluminium alloy piston bodies or to produce gas turbine blade assemblies having silicon nitride aerofoils joined to a metal root.
Description
1 GB 2 136 720 A 1
SPECIFICATION
Joining silicon nitride to metals The invention relates to the joining of silicon nitride to metals and to articles produced by such joining.
Silicon nitride is more heat-resistant than many metals such as the aluminium and aluminium alloys used in the manufacture of articles such as pistons for internal combustion engines, and the nickel and cobalt alloys used in the manufacture of blades for gas turbine engines, both of which work in a hot environment. Silicon nitride is comparatively strong at high temperatures, having a modulus of rupture of about 206 Wa. at temperatures up to 1350'C.
There are several forms of silicon nitride which can be so used such as reaction bonded silicon nitride, in which a silicon powder is compacted and reacted with nitrogen at high temperature, or hot pressed silicon nitride, which is a silicon nitride powder pressed in graphite dies at high temperature and bonded together with a glass flux, or sintered silicon nitride, which is a silicon nitride powder heated in the presence of a bonding agent such as ytrea and a magnesia so that the particles stick together, or a compound known as sialon, which is silicon nitride with oxygen and aluminium.
In many articles, however, such as pistons and gas turbine blade assemblies, it is not possible to make the whole article of silicon nitride because of the loads imposed on the article. Forthis reason, it is desirable to join silicon nitride to metals. It has not, however, so far been possible to establish such a joint by conventional welding or brazing processes because silicon nitride does not'wet' (i.e. it will not 100 carry a liquid film on its surface) and so it is not possible to coat it with conventional fluxes or other metal compounds which allow welding or brazing of the silicon nitride to the metal. Silicon nitride will, under certain circumstances, wet with highly reac tive brazes based on titanium and chromium, but these require the use of a high vacuum furnace which is expensive to operate, produces an expan sion mismatch and can give generally poor quality joints.
According to a first aspect of the invention, there is provided a method of joining silicon nitride to a metal or metal alloy and comprising bonding to a surface of the silicon nitride, firstly a layer of aluminium oxide or an alumina silica compound or 115 magnesia or magnesium oxide or mullite and secondly a layer of a ceramic metal and then joining the ceramic metal layer to a surface of the metal or metal alloy by a welding or brazing process.
According to a second aspect of the invention, there is provided a method of manufacturing a piston having a crown end thereof or a part of the crown end thereof formed from silicon nitride and the remainder of the piston formed from a metal or a metal alloy and comprising joining the silicon nitride 125 part to the metal or metal alloy portion by a method according to the first aspect of the invention.
According to a third aspect of the invention, there is provided a piston when made by the method of the second aspect of the invention.
According to a fourth aspect of the invention, there is provided a method of manufacturing a blade fora gas turbine engine and comprising forming an aerofoil portion of the blade of silicon nitride and forming a root portion of the blade of a metal of a metal alloy and then joining the aerofoil portion to the root portion by a method according to the first aspect of the invention.
According to a fifth aspect of the invention, there is provided a gas turbine blade when made by the fourth aspect of the inventiojn.
The following is a more detailed description of two embodiments of the invention, byway of example, reference being made to the accompanying draw- ings in which:- Figure 1 is a cross-section of a portion of a piston for an internal combustion engine, and Figure 2 is a schematic perspective view of a part of a blade fora gas turbine engine.
Referring first to Figure 1, the piston for an internal combustion engine comprises a body portion 10 which is, for example, cast from aluminium or an aluminium alloy or a magnesium alloy. The end of the body has a flafgenerally circular surface 11.
The piston also includes a combustion bowl 12 formed in a crown end member 13 of silicon nitride (Si3N4) in any suitable form, such as reaction bonded silicon nitride, in which a silicon powder is compacted and reacted with nitrogen at high tempera- ture, or hot pressed silicon nitride, which is a silicon nitride powder pressed in graphite dies at high temperature and bonded together with a glass flux, or sintered silicon nitride, which is a silicon nitride powder heated in the presence of a bonding agent such as ytrea and a magnesia so that the particles stick together, or a compound known as sialon, which is silicon nitride with oxygen and aluminium. The member 13 is provided with a peripheral flange 14 which has the same external diameter as the external diameter of the body 10. An annular reinforcement member 15 of a ferrous material is provided around the silicon nitride member 13 beneath the flange 14 and has an external diameter which is substantially the same as the external diameters of the flange 14 and the piston body 10.
The silicon nitride member 13 is connected to the other parts as follows.
First, the cylindrical surface 16 of the silicon nitride member 13 is sprayed with a layer of aluminium oxide (A1203). This may be done by using a plasma spray process or by any other suitable form of spray. In alternative embodiments, alumina silica compounds or magnesia or magnesium oxides or mullite (A16Si2013) may be used.
The use of a plasma a spray process ensures that the aluminium oxide is bonded firmly to the surface of the silicon nitride member 13.
Next, a layer of a ceramic metal such as nickel aluminide is sprayed onto the coating of aluminium oxide. Once again, a plasma spray process may be used or any other suitable form of spray process to ensure the formation of a firmly bonded layer.
Since nickel aluminide can be welded or brazed to metal using conventional such processes, the coated silicon nitride member 13 is then brazed to the 2 GB 2 136 720 A 2 reinforcement 15 by a conventional brazing process using a brazing paste to form a connection 17 therebetween. The assembled member 13 and the reinforcement 15 are then brazed to the upper surface 11 of the piston body 10 in a similar 20 70 fashion.
Subsequently, a ring groove or grooves are machined in the reinforcement 15 to produce a finished piston.
In this way, a piston is formed which has a crown end and a combustion bowl 12 formed from silicon nitride which can readily resist the temperatures (of, say, up to 80WC) which may be found in the cylinders of internal combustion engines, particular- ly Diesel cycle engines with a heat-insulated piston. The joining method described above with reference to Figure 1 provides a connection between the silicon nitride member 11, the body 10 and the reinforcement 15 which is strong enough to take all loads imposed on the piston.
The problem of differing coefficients of thermal expansion between the silicon nitride member 13 and the piston body 10 and the reinforcement 15 is overcome by the fact that the aluminium oxide (or alumina silica compound or magnesia or magnesium oxide mullite, where used) has a coefficient of thermal expansion intermediate the coefficients of thermal expansion of the member 13 and the body and reinforcement 10, 15, while the nickel aluminide has a coefficient of thermal expansion intermediate the coefficients of thermal expansion of the aluminium oxide and the body 10 and reinforcement 15. Thus there is a succession of materials with graded coefficients of thermal expansion which overcomes the problem of direct joints between materials having widely differing coefficients of thermal expansion.
It will be appreciated that a welding process can be used in place of the brazing process described above.
Referring nextto Figure 2, the blade comprises an aerofoil portion 20 which is formed from a silicon nitride of any of the types described above with reference to Figure 1. The aerofoil portion 20 is provided with a rectangular base 21 which forms part of the gas shroud platform and has a flat undersurface. The blade also includes a firtree root 22 which is formed from any suitable metal or metal alloy such as a nickel or cobalt alloy and having a rectangular upper surface 23 forming the remainder 115 of the gas shroud platform and corresponding to the flat undersurface of the base 21 of the aerofoil portion 20.
The two surfaces are joined using the technique described above with reference to Figure 1. The 120 undersurface of the silicon nitride aerofoil portion 20 is sprayed with a layer of aluminium oxide or an alumina silica compound, or a magnesium oxide or mullite. Onto this layer is sprayed a ceramic metal such as nickel aluminide which is in turn, welded or 125 brazed to the upper surface 23 of he root 22.
There is thus formed a composite gas turbine blade in which the silicon nitride aerofoil 20 is well able to withstand the hot conditions encountered in the turbine in operation, while the metal or metal 130 alloy root 22 is well able to bear the stresses placed on the blade. This avoids the stressing problems encountered in the roots of blades formed entirely from silicon nitride. The graded coefficients of thermal expansion of the layers overcome the problem of differential expansion of the aerofoil and the root.
It will be appreciated that composite silicon nitride/metal or metal alloy parts, joined as described above, could be used for form other gas turbine parts which encounter the hot turbine gases and are stressed in use. For example, composite turbine shrouds and other hot gas path components could be made in this way. Indeed, the method described can be used whenever it is required to join silicon nitride to a metal or metal alloy.
Claims (12)
1. A method of joining silicon nitride to a metal or metal alloy and comprising bonding to a surface of the silicon nitride, firstly a layer of aluminium oxide or an aluminja silica compound or magnesia or magnesium oxide or mullite and secondly a layer of a ceramic metal and then joining the ceramic metal layer to a surface of the metal or metal alloy by a welding or brazing process.
2. A method according to claim 1, and where the metal or metal alloy has a coefficient of thermal expansion which is greater than the coefficient of thermal expansion of silicon nitride, the method comprising selecting the material of the first layer to have a coefficient of thermal expansion intermediate the coefficients of thermal expansion of the silicon nitride and the metal or metal alloy, and selecting the material of the second layer to have a coefficient of thermal expansion intermediate the coefficients of thermal expansion of the first layer and the metal or metal alloy.
3. A method according to claim 1 or claim 2, wherein the ceramic metal is nickel aluminide.
4. A method according to anyone of claims 1 to 3, wherein at least one of the first and second layers is formed by a plasma spray process.
5. A method of joining silicon nitride to a metal or metal alloy and substantially as hereinbefore described with reference to the accompanying drawings.
6. A method of manufacturing a piston having a crown end thereof or a part of the crown end thereof formed from silicon nitride and the remainder of the piston formed from a metal or a metal alloy and comprising joining the silicon nitride part to the metal or metal alloy portion by a method according to any one of claims 1 to 5.
7. A method according to claim 6, wherein the silicon nitride part defines a combustion bowl of the piston.
8. A method of manufacturing a piston substantially as hereinbefore described with reference to Figure 1 of the accompanying drawings.
9. A piston for an internal combustion engine when made by the the method of any one of claims 6 to 8.
10. A method of manufacturing a blade fora gas ip c 3 GB 2 136 720 A 3 turbine engine and comprising forming an aerofoil portion of the blade of silicon nitride and forming a root portion of the blade of a metal or a metal alloy and then joining the aerofoil portion to the root portion by a method according to any one of claims 1 to 4.
11. A method of manufacturing a blade fora gas turbine engine substantially as hereinbefore described with reference to Figure 2 of the accompany10 ing drawings.
12. A blade fora gas turbine engine when made by the method of claim 10 or claim 11.
Printed in the U K for HMSO, D8818935,7184,7102. Published by The Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8232821 | 1982-11-17 |
Publications (3)
Publication Number | Publication Date |
---|---|
GB8330304D0 GB8330304D0 (en) | 1983-12-21 |
GB2136720A true GB2136720A (en) | 1984-09-26 |
GB2136720B GB2136720B (en) | 1985-12-18 |
Family
ID=10534328
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB8330304A Expired GB2136720B (en) | 1982-11-17 | 1983-11-14 | Joining silicon nitride to metals |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP0109814B1 (en) |
JP (1) | JPS59156570A (en) |
CA (1) | CA1225881A (en) |
DE (1) | DE3375567D1 (en) |
GB (1) | GB2136720B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2239214A (en) * | 1989-12-23 | 1991-06-26 | Rolls Royce Plc | A sandwich structure and a method of manufacturing a sandwich structure |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS59190279A (en) * | 1983-04-13 | 1984-10-29 | 株式会社東芝 | Ceramic structure and manufacture |
JPS60131874A (en) * | 1983-12-19 | 1985-07-13 | 三菱重工業株式会社 | Method of bonding ceramic and metal |
JPS60190651A (en) * | 1984-03-12 | 1985-09-28 | Ngk Insulators Ltd | Engine piston and manufacturing method thereof |
US4602731A (en) * | 1984-12-24 | 1986-07-29 | Borg-Warner Corporation | Direct liquid phase bonding of ceramics to metals |
GB8622538D0 (en) * | 1986-09-18 | 1986-10-22 | Ae Plc | Pistons |
GB8818214D0 (en) * | 1988-07-30 | 1988-09-01 | T & N Technology Ltd | Pistons |
DE69213802T2 (en) * | 1991-04-09 | 1997-02-27 | Ngk Insulators Ltd | Use of an oxide layer to improve the oxidation and corrosion resistance of a gas turbine blades made of silicon nitride |
FR2720392B1 (en) * | 1994-05-25 | 1996-08-02 | Onera (Off Nat Aerospatiale) | Method and composition for assembling ceramic and refractory alloy parts. |
US6355356B1 (en) * | 1999-11-23 | 2002-03-12 | General Electric Company | Coating system for providing environmental protection to a metal substrate, and related processes |
US20090266870A1 (en) * | 2008-04-23 | 2009-10-29 | The Boeing Company | Joined composite structures with a graded coefficient of thermal expansion for extreme environment applications |
US8512808B2 (en) | 2008-04-28 | 2013-08-20 | The Boeing Company | Built-up composite structures with a graded coefficient of thermal expansion for extreme environment applications |
US10280769B2 (en) * | 2013-09-30 | 2019-05-07 | United Technologies Corporation | Nonmetallic airfoil with a compliant attachment |
US9969654B2 (en) | 2014-01-24 | 2018-05-15 | United Technologies Corporation | Method of bonding a metallic component to a non-metallic component using a compliant material |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB927611A (en) * | 1958-07-19 | 1963-05-29 | Telefunken Gmbh | Improvements in or relating to methods of forming an adherent layer on a sintered ceramic body |
GB1015506A (en) * | 1962-08-27 | 1966-01-05 | Gen Electric Co Ltd | Improvements in or relating to devices incorporating bodies of polycrystalline alumina |
GB1017487A (en) * | 1963-06-26 | 1966-01-19 | Philips Electronic Associated | Improvements relating to methods of applying a layer containing a metal having a high melting-point to a ceramic article |
GB2047151A (en) * | 1979-03-29 | 1980-11-26 | Ford Motor Co | Joining silicon nitride based bodies |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4214906A (en) * | 1974-11-29 | 1980-07-29 | Volkswagenwerk Aktiengesellschaft | Method of producing an article which comprises a first zone of a nonoxide ceramic material and a second zone of a softer material |
GB1588516A (en) * | 1977-08-30 | 1981-04-23 | Ass Eng Ltd | Pistons |
GB2027518A (en) * | 1978-05-23 | 1980-02-20 | British Internal Combust Eng | Pistons |
JPS5777078A (en) * | 1980-10-27 | 1982-05-14 | Komatsu Mfg Co Ltd | Ceramics and metal jointing method |
-
1983
- 1983-11-14 DE DE8383306934T patent/DE3375567D1/en not_active Expired
- 1983-11-14 GB GB8330304A patent/GB2136720B/en not_active Expired
- 1983-11-14 EP EP83306934A patent/EP0109814B1/en not_active Expired
- 1983-11-16 CA CA000441303A patent/CA1225881A/en not_active Expired
- 1983-11-17 JP JP21512983A patent/JPS59156570A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB927611A (en) * | 1958-07-19 | 1963-05-29 | Telefunken Gmbh | Improvements in or relating to methods of forming an adherent layer on a sintered ceramic body |
GB1015506A (en) * | 1962-08-27 | 1966-01-05 | Gen Electric Co Ltd | Improvements in or relating to devices incorporating bodies of polycrystalline alumina |
GB1017487A (en) * | 1963-06-26 | 1966-01-19 | Philips Electronic Associated | Improvements relating to methods of applying a layer containing a metal having a high melting-point to a ceramic article |
GB2047151A (en) * | 1979-03-29 | 1980-11-26 | Ford Motor Co | Joining silicon nitride based bodies |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2239214A (en) * | 1989-12-23 | 1991-06-26 | Rolls Royce Plc | A sandwich structure and a method of manufacturing a sandwich structure |
GB2239214B (en) * | 1989-12-23 | 1993-11-03 | Rolls Royce Plc | A sandwich structure and a method of manufacturing a sandwich structure |
Also Published As
Publication number | Publication date |
---|---|
CA1225881A (en) | 1987-08-25 |
EP0109814A3 (en) | 1985-03-13 |
EP0109814B1 (en) | 1988-02-03 |
GB8330304D0 (en) | 1983-12-21 |
DE3375567D1 (en) | 1988-03-10 |
JPS59156570A (en) | 1984-09-05 |
EP0109814A2 (en) | 1984-05-30 |
GB2136720B (en) | 1985-12-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0109814B1 (en) | Joining silicon nitride to metals | |
US4740429A (en) | Metal-ceramic joined articles | |
KR100757603B1 (en) | A coating system for providing environmental protection to a metal substrate, and related processes | |
US4602731A (en) | Direct liquid phase bonding of ceramics to metals | |
GB2117799A (en) | Composite ceramic metal components | |
US5975407A (en) | Method using a thick joint for joining parts in SiC-based materials by refractory brazing and refractory thick joint thus obtained | |
US4624404A (en) | Method for bonding ceramics and metals | |
JP2004003017A (en) | Method for forming channel on surface of metallic substrate and article referring thereto | |
US20050040210A1 (en) | Method of joining ceramic or graphite to metal with an alloy having high nickel or cobalt content, alloys for joining the same, and products formed therewith | |
US4698271A (en) | Copper-silver-titanium filler metal for direct brazing of structural ceramics | |
US4580714A (en) | Hard solder alloy for bonding oxide ceramics to one another or to metals | |
EP0932472B1 (en) | Method for joining rhenium to columbium | |
GB2130244A (en) | Forming coatings by hot isostatic compaction | |
EP1135348A2 (en) | Method for joining ceramic to metal | |
JPH02128832A (en) | Honeycomb structure | |
JPH02128833A (en) | Honeycomb core | |
JPH0580434B2 (en) | ||
JPS61117172A (en) | Ceramic bonding structure | |
JPS6191074A (en) | Structure for bonding ceramic axis and metal axis | |
JPH04162957A (en) | Hard facing method for hardly weldable high-temperature resistant member | |
Singh et al. | Advanced joining and integration technologies for ceramic matrix composite systems | |
JPS60251180A (en) | Method of bonding ceramic member and metal member | |
JPS6380916A (en) | Ceramic lining method for pipe inner face | |
JPH0371391B2 (en) | ||
Moore | Joining Silicon Nitride to Metals |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19931114 |