CA2217702A1 - Method for the chemical vapour infiltration of a material consisting of carbon and silicon and/or boron - Google Patents
Method for the chemical vapour infiltration of a material consisting of carbon and silicon and/or boron Download PDFInfo
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- CA2217702A1 CA2217702A1 CA002217702A CA2217702A CA2217702A1 CA 2217702 A1 CA2217702 A1 CA 2217702A1 CA 002217702 A CA002217702 A CA 002217702A CA 2217702 A CA2217702 A CA 2217702A CA 2217702 A1 CA2217702 A1 CA 2217702A1
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- 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
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/04—Coating on selected surface areas, e.g. using masks
- C23C14/046—Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
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- 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
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
- C04B35/56—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides
- C04B35/565—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on silicon carbide
- C04B35/571—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbides or oxycarbides based on silicon carbide obtained from Si-containing polymer precursors or organosilicon monomers
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- 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
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/71—Ceramic products containing macroscopic reinforcing agents
- C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
- C04B35/80—Fibres, filaments, whiskers, platelets, or the like
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- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacturing & Machinery (AREA)
- Structural Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Chemical Vapour Deposition (AREA)
Abstract
Infiltration is carried out within a porous substrate at a temperature no higher than 1050 ~C, and the gas phase contains a gaseous precursor of the material to be infiltrated as well as hydrogen chloride (HCl), the proportion by volume thereof relative to the gaseous precursor of silicon (e.g.
methyltrichlorosilane) and/or boron, e.g. BCl3, preferably being of at least 25 %.
methyltrichlorosilane) and/or boron, e.g. BCl3, preferably being of at least 25 %.
Description
METHOD FOR THE CHE~ICAL VAPOUR INFILTRATION OF A MATERIAL CONSISTING
OF CARBON AND SILICON AND/OR BORON.
The present invention relates to a method of densifying a porous substrate by means of a material obt~;ne~ by chemical vapor infiltration and comprising carbon together with silicon and/or boron. Such a material may be silicon carbide, boron carbide, and any intermediate Si-B-C ternary system.
A particular application of the invention lies in the field of making parts out of composite material by densifying a fiber substrate or "preform" with a matrix obtained by chemical vapor infiltration and constituted at least in part by a material comprising carbon together with silicon and/or boron.
Methods and an apparatus for chemical vapor infiltration and serving in particular to manufacture composite material parts having an SiC matrix are described, for example, in documents FR-A-2 401 888, FR-A-2 567 874, and W0 87/04733, while densification of preforms by a matrix constituted at least in part by an Si-B-C ternary system is described in document FR-A-2 668 477.
The fiber preforms to be densified are placed in the reaction chamber of an infiltration oven. A gas that is a precursor of the matrix to be formed is admitted into the chamber, e.g. into the top thereof. The co~~o~-y-used precursor gas for SiC is methyltricholosilane (MTS) together w;ith hydrogen (H2). The cc o~ly-used precursor gas for boron carbide is a mixture of boron chloride (BCl3) and a gaseous hydrocarbon or mixture of hydrocarbons, e.g. propane (C3H8) and/or methane (CH4) or natural gas. A matrix or a portion of matrix comprising an Si-B-C ternary system is obt~ , for example, from a mixture of MTS and of BC13 in appropriate proportions together with H2. Under determined conditions of temperature and pressure, the gas diffuses into the accessible pores of the preforms, penetrates to the cores of the preforms, and reacts to form the desired deposit on the fibers. On entry into the chamber, the gas may be preheated, e.g. by passing through perforated plates raised to the temperature that obtains inside the chamber. The residual gases are extracted by pumping through an outlet situated at the base of the chamber.
Such methods give results that are satisfactory providing the volume actually occupied by the preforms in the reaction chamber is small. This applies when the preforms require support tooling to be present in order to conserve their shapes, and when they are thin or very widely spaced apart from one another inside the oven.
Examples of such preforms are those designed to constitute thermal protection elements that fit closely over the shape of space vehicle fairings, or to constitute flaps for aircraft jet engines. It is then common for the effective occupancy rate of the oven, i.e.
the volume percentage of the reaction chamber actually occupied by the preforms, to be less than 5%.
However, the performance of those known methods falls off considerably when the occupancy rate of an oven is significantly increased. Such an increase is possible with preforms that are simple in shape, that do not require supporting tooling, or that are thick. This applies in particular to thick needled preforms designed to constitute friction parts, in particular airplane brake disks made of composite material having a matrix of SiC or Si-B-C, or at least partially of SiC or Si-B-C.
Such preforms are of a shape that enables them to be stacked and to achieve an occupancy rate of greater than 25% or even greater than 30~. The observed lowering of performance in known infiltration methods consists, in particular, in very marked non-uniformity of the densification in the longitudinal direction, i.e. in the flow direction of the gas from its inlet into the reaction chamber to the outlet thereof. It is observed that the preforms closest to the gas inlet are densified much more and much more quickly than those further away therefrom.
Another drawback encountered is marked non-uniformity of the densification of thick preforms, i.e.
the existence of a steep densification gradient between the core of a part into which less matrix is admitted, and zones of the same part close to its outside surface, where a larger amount of gas is admitted.
For obvious reasons of throughput in infiltration ovens and of producing high quality parts, it is necessary to reduce such densification non-uniformities as much as possible.
Longitll~; n~ non-uniformity of densification is the result essentially of the gas being depleted as it moves through the reaction chamber. It might be envisaged that that could be remedied by increasing the flow rate of the gas admitted into the oven. Unfortunately, that gives rise to even faster and greater densification of the preforms situated close to the gas inlet, without attenuating the densification gradient within the parts.
An object of the present invention is to provide a method of chemically infiltrating a vapor of a material comprising carbon together with silicon and/or boron, which enables the effective occupancy ratio of infiltration ovens to be increased while greatly limiting densification non-uniformity in the reaction chambers of ovens between their gas inlets and their residual gas outlets.
Another object of the invention is to provide a chemical vapor infiltration method that enables the densification gradient within thick parts to be reduced.
According to a method of the invention, chemical vapor infiltration within a porous substrate is performed at a temperature not greater than 1050~C by means of a gas cont~; n; ng a gaseous precursor of the material comprising carbon together with silicon and/or boron, and also cont~in;ng hydrogen chloride (HCl). The gaseous precursor is constituted by a gas or a mixture of gases.
The volume proportion of HCl relative to the gaseous precursor for silicon and/or boron is preferably at least 10%, e.g. not less than 25%, and, for example, the silicon precursor may be MTS, and the boron precursor may be BCl3.
It has been found that including HCl in the gas makes it possible to avoid premature depletion thereof.
The presence of HCl slows down matrix formation in the parts first exposed to the gas penetrating into the infiltration oven. This makes it possible to increase the flow rate of the precursor gas, and consequently the occupancy ratio of the oven, without encountering the above-mentioned drawbacks.
Chemical vapor infiltration can be performed with a temperature gradient, i.e. by heating the porous substrate in such a manner that it presents a higher temperature in portions that are remote from its exposed surfaces than it does at its exposed surfaces.
Since matrix formation is ~nhA~ in those portions of the substrate where the temperature is higher, establishing a temperature gradient serves to counter the non-uniformity of densification within the substrate.
Substrate heating can be performed by contact between a surface of the substrate and a heated body, such that a temperature gradient is established between the surface of the substrate which is in contact with the heated body and the surfaces of the substrate which are exposed to the flow of gas. The heated body may be a heater core electromagnetically coupled to an inductor.
When the substrate is made of an electrically-conductive material, e.g. carbon, it can be heated by induction by direct coupling with an inductor.
These chemical vapor infiltration t~rhniques using a temperature gradient are described in document FR-A-2 711 647.
Implementations of methods of the invention are described below in greater detail.
Reference is made to the ~ccomranying drawings, in which:
~ Figure 1 is a highly diagrammatic view of an installation enabling a method of chemical infiltration to be implemented using the vapor of a material comprising carbon together with silicon and/or boron, and at constant temperature; and ~ Figure 2 is a highly diagrammatic view of an installation enabling a method of chemical infiltration to be implemented using the vapor of a material comprising carbon together with silicon and/or boron, and with a temperature gradient.
The installation shown in Figure 1 is of the same type as that described in above-mentioned document W0 87/04733.
A graphite heater core lO housed inside a sealed metal enclosure 12 defines a reaction chamber 14. Inside the enclosure 12, the core 10 is surrounded by a metal inductor 16 with thermal insulation 18 being interposed between them. The core 10 is in the form of a vertical axis cylinder closed in sealed ~nne~ by a bottom wall lOa and by a removable top cover lOb.
Inside the chamber 14, the substrates to be densified are supported by a base turntable 20 capable of rotating about a vertical axis which coincides with the axis of the core 10 and of the inductor 16. Support trays 22 and 24 supported by the turntable 20 with interposed spacers 25 make it possible to load substrates at several levels, at least three in the example shown.
Rotation of the turntable 20 is controlled by a motor (not shown) coupled to a shaft 26 passing through the bottom wall of the enclosure 12 and through the bottom wall lOa of the core, and it is fixed to the bottom face of the turntable 20.
The gas for forming the matrix material which is to densify the substrates is admitted via a pipe 28 which leads to the top of the chamber 14, passing through the cover lOb. The gas comprises a mixture of a gaseous precursor for the matrix material together with HCl. The gaseous precursor depends on the nature of the matrix.
For an SiC matrix, the gaseous precursor is MTS together with H2. For a boron carbide matrix, the gaseous precursor is a mixture of BCl3 and a carbon precursor.
The carbon precursor may be an alkane, an alkyl, or an alkene, on its own or in a mixture, e.g. a mixture of C3H8 and of CH4 (or of natural gas). For a matrix constituted by an Si-B-C ternary system, the gaseous precursor is a mixture of MTS and BCl3 together with H2. The MTS, BCl3, C3H8 + CH4, Hz, and HCl gases come from sources 30, 31, 32, 33, and 34 via feed ducts 36, 37, 38, 39, and 40 provided with injection valves 42, 43, 44, 45, and 46 l~;ng to the pipe 28.
Residual gas is extracted from the chamber 14 by opening a valve 48 which puts the chamber 14 into communication with pumping apparatus 50 via at least one exhaust pipe 52. By way of example, the pumping apparatus 50 can be a water ring pump. The pipe 52 ~o~lln;cates with the bottom portion of the chamber 14 via an annular passage 54 formed around the shaft 26.
Signals delivered by a pressure sensor 56 and a temperature sensor 58 represent the pressure and the temperature in the chamber 14 and are transmitted to a controller 60. The controller controls the pump 50 and the valve 48 to establish the desired pressure in the chamber 14 prior to admitting the gas, and it controls a generator 62 feeding the inductor 16 so as to maintain the temperature inside the enclosure at the desired value. The controller 60 also controls the valves 42, 43, 44, 45, and 46 to control the respective flow rates of MTS, BCl3, CH4 + C3H8, H2, and HCl as a function of the predetermined composition of the gas.
The gas penetrating into the reaction chamber 14 comes initially into contact with a preheater 64, e.g. in the form of superposed perforated plates. Since the preheater plates are inside the reaction chamber, they are continuously at the temperature which obtains therein. This makes it possible to raise the gas to the desired temperature before it comes into contact with the substrates that are to be densified.
The volume situated around the core 10 inside the enclosure can be swept continuously by an inert gas such as nitrogen (Nz). This comes from a gas source 65 via a duct 66 provided with a valve 68 under the control of the controller 60. The nitrogen thus forms a blanket of inert gas around the reaction chamber. It is extracted via a duct 69 leading to the exhaust pipe 52 outside the enclosure 12.
Tests conc~ning chemical vapor infiltration of an SiC matrix have been performed with the above-described installation. During each test, on each of the three loading levels in the oven, there was placed the same set of porous substrates constituted by:
~ a cylindrical sample A comprising a needled carbon fiber texture having a diameter of 90 mm and a thickness of 35 mm;
~ three cylindrical samples B of the same texture, having a diameter of 35 mm and a height of 35 mm;
~ a cylindrical sample C of the same texture having a diameter of 15 mm and a height of 35 mm;
~ a cylindrical sample D of the same texture, having a diameter of 15 mm and a height of 8 mm; and ~ a sample E in the form of a cube having a side of about 2 cm3, and comprising a substrate of carbon fibers partially densified by vacuum suction of a powder.
The texture of samples A, B, C, and D was made by stacking and needling two~directional sheets of carbon fibers progressively, as described in document FR-A-2 584 106. The texture is identical to that constituting the preforms for the carbon-carbon composite material brake disks fitted to airplanes of the "Airbus"
type.
The substrate of sample E was constituted by a carbon fiber felt partially densified by vacuum suction of carbon powder, as described in document FR-A-2 671 797.
Each of the tests was performed at a pressure (P) in the reaction chamber of 10 kPa, with a ratio between the flow rates of H2 and of MTS (Q(H2) and Q(MTS)) equal to 6 for a total duration (d) of 20 hours (h).
A first series of three tests I, II, and III was performed at a temperature T in the reaction chamber of 1010~C, with Q(MTS) e~ual to 150 st~n~d cm3/min (sccm), and with Q(H2) equal to 900 sccm, while giving the HCl flow rates (Q(HCl)) of 0, 37.5 sccm, and 75 sccm respectively, i.e. proportions successively equal to 0, 25%, and 50~ of HCl flow rate relative to that of MTS.
A fourth test IV was performed by doubling Q(MTS) and Q(H2) compared with test III, leaving the other parameters unchanged.
A fifth test V was performed under the same conditions as test IV, except that the temperature T was lowered from 1010~C to 950~C.
A sixth test VI was performed under the same conditions as test V, with the exception of the HCl flow rate Q(HCl) being doubled from 75 sccm to 150 sccm.
In order to characterize the performance obt~; n~
concerning SiC densification of the substrates, the following characteristics were evaluated:
~the relative mass increase ~m/m of each substrate, ~m being the difference between the mass m' of the substrate at the end of the test (after densification) and the initial mass _ of the substrate;
~ longit~-~; n~ non-uniformity of densification (between the gas inlet and outlet), i.e. variation of densification as a function of the location of the substrates in the reaction chamber, evaluated for each type of substrate by measuring the ratio between the mass increase ~m/m at the "top" level (closest to the gas inlet) and the mass increase ~m/m at the "bottom" level (furthest from the gas inlet);
~ non-uniformity of infiltration, i.e. the gradient of densification between the core and the surface of each substrate evaluated by measuring the ratio between the mass uptake ~m/m of substrate A having the greatest volume and the mass uptake ~m/m of the substrate C having the smallest volume of substrates A, B, and C having the same nature and height, with this being done at the "top", "middle", and "bottom" levels of the reaction chamber;
~ the thickness of the SiC deposit on the fibers, evaluated by laser diffraction, to accuracy of the order of 0.1 ~; and ~ densification efficiency evaluated by calculating the ratio of the mass uptake actually achieved by the substrates to the total mass uptake that would theoretically be possible as a function of the quantity of MTS consumed.
The results obt~;n~ are brought together in Tables I to IV below.
TABLE I
Mass increase P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) 1010 1010 1010 1010 950 950 conditions Q(MTS)sccm150 150 150 300 300 300 Q(H2)sccm900 900 900 1800 1800 1800 Q(HCl)sccm 0 37.5 75 75 75 150 T33.131.1 22.8 57.3 36.2 32.3 A M 17.5 10.1 3.8 33.8 20.6 23.6 B 1.8 0.6 0.7 15.7 10.9 12.5 T 72.4 76 68.9 137 89 56.8 B M 27.1 25.8 16.6 54.7 34.1 33.4 B 4.4 0.9 1.3 32.2 20.2 21.1 T 113 110 111 208 134 68.6 Substrate C M 29.6 18.3 9.4 52.5 25 26.2 ~m/m(~) B 2.7 0.9 1.2 32.8 15.9 18.8 T 231 106.5 106 313 196 91.8 D M 29.6 18.3 4.1 123107.386.6 B 2.7 0.8 1.9 24.5 67.7 61 T 10.9 10.1 7.8 11.2 10 9.9 E M 1.4 0.9 1.7 6 10 8.5 B 0.2 1 1.4 0.5 6.8 7.5 Where the letters T, M, and B identify the "top", "middle", and "bottom" levels in the reaction chamber.
Clearly, the cycles performed by doublîng the MTS
and H2 flow rates gave rise to greater mass uptakes. The most uniform densifications were those performed at the lower temperature (950~C) in particular in the presence of HCl.
TABLE II
Longitudinal non-uniformity P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) 10101010 . 1010 .1010 ~ 950 950 conditions Q(MTS)sccm150 150 150 300 300 300 Q(H2)sccm900 900 900 18001800 1800 Q(HCl)sccm0 37.5 75 75 75 150 A18.451.832.6 3.6 3.3 2.6 B16.484.4 53 4.3 4.4 2.7 Substrates C 41.9 122.292.5 6.3 8.4 3.6 D 85.6133.1 55.812.8 2.9 1.5 E 54.5 10.1 5.622.4 1.5 1.3 The results ~om; n~ closest to the ideal optimum value (1) were for the cycle performed at doubled flow rates of MTS and H2, at the lower temperature and in the presence of HCl.
TABLE III
Densification non-uniformity _ P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) ,1010 10101010 .1010 950 . 950 conditions Q(MTS)sccm150 150 150 300 300 300 Q(Hz)sccm900 900 900 1800 1800 5 1800 Q(HCl)sccmO 37.5 75 75 75 150 T0.290.280.210.280.27 0.47 Level M 0.59 0.56 0.410.640.82 0.9 B 0.66 0.67 0.580.480.68 0.66 As before the best results were obt~i n~ with the cycle having doubled flow rates of MTS and H2, at low temperature, and in the presence of HCl.
TABLE IV
Efficiency P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) 1010. 1010.1010. 1010 950 950 conditions Q(MTS)sccm 150 150 150 300 300 300 Q(H2)sccm 900 900 900 1800 1800 1800 Q(HCl)sccm 0 37.5 75 75 75 150 T 28.1 26.5 23.3 22.9 17 13 10 Level M 13 8.7 4.7 11.5 8 9 B 1.6 0.5 0.1 5.8 4.4 5.1 Total42.7 35.7 28.1 40.2 29.4 27.1 For cycles at doubled flow rates of MTS and H2, and at low temperature (950~C), the presence of HCl reduces efficiency, but it is better distributed throughout the load in the oven, and another point which is also important industrially, there were practically no unwanted deposits on the preheating plates.
The results brought together in the above tables ~ show conclusively the advantage in terms of reducing non-uniformity of SiC densification both throughout the volume of the oven and throughout the volume of a single part, and of performing chemical vapor infiltration at a relatively low temperature, preferably less than 100~C, in the presence of HCl, and with an increased flow rate of MTS.
The process of chemically infiltrating SiC vapor can be implemented with a temperature gradient, e.g. by means of an installation such as that shown diagrammatically in Figure 2.
This installation is more particularly designed for densifying annular preforms 100 such as the brake disk preforms made of a material that conducts heat, such as carbon in fiber form. The preforms are stacked around a central cylindrical graphite core 110 constituting a heater core, with the assembly being supported by a stationary insulating tray 120. The preforms 100 may be slightly spaced apart from one another by means of spacers 102 so as to facilitate access by the gas to the main faces of the preforms. The reaction chamber 114 in which the core and the preforms to be densified are received is defined by an insulating wall 118 that does not conduct electricity, having a bottom wall 118a and a cover 118b. An inductor 116 surrounds the wall 118, while still being inside an enclosure 112.
The means for f~;~g the chamber 114 with MTS + H2 + HCl gas and for extracting residual gas are similar to those of the installation of Figure 1 and they are not shown. Nevertheless, it may be observed that the exhaust pipe 152 leads directly to the bottom portion of the chamber 114 through the bottom wall 118a. In addition, the chamber 114 is not provided with means for preheating the incoming gas.
The core 110 is heated by electromagnetic coupling with the inductor 116. The annular preforms are heated by having their inside cylindrical surfaces in contact with the core 110. A temperature gradient is then established between these inside surfaces and the exposed outside surfaces thereof, which surfaces are cooled by radiation and by convection in contact with the gas that has penetrated into the chamber. This gradient depends in particular on the ~;me~ional and heat conductivity characteristics of the preforms. The generator 162 fee~; ng the inductor 116 is controlled so that, at least at the beg; nn; ng of the infiltration process, the temperature of preform portions adjacent to the core is significantly higher than the minimum temperature for SiC
deposition, i.e. about 700~C. SiC densification then takes place preferentially in those portions of the preforms. This prevents portions of the preforms close to their outside surfaces densifying too quickly, since that could lead to premature clogging of the pores, preventing densification in the cores of the preforms and r CA 02217702 1997-10-07 generating a steep densification gradient within the resulting parts.
The concept of performing chemical vapor infiltration with a temperature gradient is known. Here it constitutes a particularly advantageous application because of the presence of HCl in the gas, which presence has a particularly beneficial effect on the uniformity of the matrix.
In the installation of Figure 2, the substrates 100 are heated by means of the heater core 110 with which they are in contact. When the conductive nature of the substrates makes it possible (e.g. substrates made of carbon or graphite having a relatively high fiber content), it is possible to envisage heating the substrates at least in part by direct coupling with the inductor, in which case the core may optionally be omitted. Although the induced currents occur mostly in the vicinity of the surfaces of the substrates, the desired temperature gradient is established because the exposed surfaces of the substrates are cooled by radiation and convection.
The method of the invention is suitable for chemically infiltrating the vapor of a material made of carbon together with silicon and/or boron into any type of substrate capable of withstanding the operating conditions and chemically compatible with the gas. The method can be used to perform densification with a matrix constituted solely or partially of this material. In which case, the matrix may also include one or more matrix phases constituted by other materials deposited before and/or after the material made of carbon together with silicon and/or boron.
OF CARBON AND SILICON AND/OR BORON.
The present invention relates to a method of densifying a porous substrate by means of a material obt~;ne~ by chemical vapor infiltration and comprising carbon together with silicon and/or boron. Such a material may be silicon carbide, boron carbide, and any intermediate Si-B-C ternary system.
A particular application of the invention lies in the field of making parts out of composite material by densifying a fiber substrate or "preform" with a matrix obtained by chemical vapor infiltration and constituted at least in part by a material comprising carbon together with silicon and/or boron.
Methods and an apparatus for chemical vapor infiltration and serving in particular to manufacture composite material parts having an SiC matrix are described, for example, in documents FR-A-2 401 888, FR-A-2 567 874, and W0 87/04733, while densification of preforms by a matrix constituted at least in part by an Si-B-C ternary system is described in document FR-A-2 668 477.
The fiber preforms to be densified are placed in the reaction chamber of an infiltration oven. A gas that is a precursor of the matrix to be formed is admitted into the chamber, e.g. into the top thereof. The co~~o~-y-used precursor gas for SiC is methyltricholosilane (MTS) together w;ith hydrogen (H2). The cc o~ly-used precursor gas for boron carbide is a mixture of boron chloride (BCl3) and a gaseous hydrocarbon or mixture of hydrocarbons, e.g. propane (C3H8) and/or methane (CH4) or natural gas. A matrix or a portion of matrix comprising an Si-B-C ternary system is obt~ , for example, from a mixture of MTS and of BC13 in appropriate proportions together with H2. Under determined conditions of temperature and pressure, the gas diffuses into the accessible pores of the preforms, penetrates to the cores of the preforms, and reacts to form the desired deposit on the fibers. On entry into the chamber, the gas may be preheated, e.g. by passing through perforated plates raised to the temperature that obtains inside the chamber. The residual gases are extracted by pumping through an outlet situated at the base of the chamber.
Such methods give results that are satisfactory providing the volume actually occupied by the preforms in the reaction chamber is small. This applies when the preforms require support tooling to be present in order to conserve their shapes, and when they are thin or very widely spaced apart from one another inside the oven.
Examples of such preforms are those designed to constitute thermal protection elements that fit closely over the shape of space vehicle fairings, or to constitute flaps for aircraft jet engines. It is then common for the effective occupancy rate of the oven, i.e.
the volume percentage of the reaction chamber actually occupied by the preforms, to be less than 5%.
However, the performance of those known methods falls off considerably when the occupancy rate of an oven is significantly increased. Such an increase is possible with preforms that are simple in shape, that do not require supporting tooling, or that are thick. This applies in particular to thick needled preforms designed to constitute friction parts, in particular airplane brake disks made of composite material having a matrix of SiC or Si-B-C, or at least partially of SiC or Si-B-C.
Such preforms are of a shape that enables them to be stacked and to achieve an occupancy rate of greater than 25% or even greater than 30~. The observed lowering of performance in known infiltration methods consists, in particular, in very marked non-uniformity of the densification in the longitudinal direction, i.e. in the flow direction of the gas from its inlet into the reaction chamber to the outlet thereof. It is observed that the preforms closest to the gas inlet are densified much more and much more quickly than those further away therefrom.
Another drawback encountered is marked non-uniformity of the densification of thick preforms, i.e.
the existence of a steep densification gradient between the core of a part into which less matrix is admitted, and zones of the same part close to its outside surface, where a larger amount of gas is admitted.
For obvious reasons of throughput in infiltration ovens and of producing high quality parts, it is necessary to reduce such densification non-uniformities as much as possible.
Longitll~; n~ non-uniformity of densification is the result essentially of the gas being depleted as it moves through the reaction chamber. It might be envisaged that that could be remedied by increasing the flow rate of the gas admitted into the oven. Unfortunately, that gives rise to even faster and greater densification of the preforms situated close to the gas inlet, without attenuating the densification gradient within the parts.
An object of the present invention is to provide a method of chemically infiltrating a vapor of a material comprising carbon together with silicon and/or boron, which enables the effective occupancy ratio of infiltration ovens to be increased while greatly limiting densification non-uniformity in the reaction chambers of ovens between their gas inlets and their residual gas outlets.
Another object of the invention is to provide a chemical vapor infiltration method that enables the densification gradient within thick parts to be reduced.
According to a method of the invention, chemical vapor infiltration within a porous substrate is performed at a temperature not greater than 1050~C by means of a gas cont~; n; ng a gaseous precursor of the material comprising carbon together with silicon and/or boron, and also cont~in;ng hydrogen chloride (HCl). The gaseous precursor is constituted by a gas or a mixture of gases.
The volume proportion of HCl relative to the gaseous precursor for silicon and/or boron is preferably at least 10%, e.g. not less than 25%, and, for example, the silicon precursor may be MTS, and the boron precursor may be BCl3.
It has been found that including HCl in the gas makes it possible to avoid premature depletion thereof.
The presence of HCl slows down matrix formation in the parts first exposed to the gas penetrating into the infiltration oven. This makes it possible to increase the flow rate of the precursor gas, and consequently the occupancy ratio of the oven, without encountering the above-mentioned drawbacks.
Chemical vapor infiltration can be performed with a temperature gradient, i.e. by heating the porous substrate in such a manner that it presents a higher temperature in portions that are remote from its exposed surfaces than it does at its exposed surfaces.
Since matrix formation is ~nhA~ in those portions of the substrate where the temperature is higher, establishing a temperature gradient serves to counter the non-uniformity of densification within the substrate.
Substrate heating can be performed by contact between a surface of the substrate and a heated body, such that a temperature gradient is established between the surface of the substrate which is in contact with the heated body and the surfaces of the substrate which are exposed to the flow of gas. The heated body may be a heater core electromagnetically coupled to an inductor.
When the substrate is made of an electrically-conductive material, e.g. carbon, it can be heated by induction by direct coupling with an inductor.
These chemical vapor infiltration t~rhniques using a temperature gradient are described in document FR-A-2 711 647.
Implementations of methods of the invention are described below in greater detail.
Reference is made to the ~ccomranying drawings, in which:
~ Figure 1 is a highly diagrammatic view of an installation enabling a method of chemical infiltration to be implemented using the vapor of a material comprising carbon together with silicon and/or boron, and at constant temperature; and ~ Figure 2 is a highly diagrammatic view of an installation enabling a method of chemical infiltration to be implemented using the vapor of a material comprising carbon together with silicon and/or boron, and with a temperature gradient.
The installation shown in Figure 1 is of the same type as that described in above-mentioned document W0 87/04733.
A graphite heater core lO housed inside a sealed metal enclosure 12 defines a reaction chamber 14. Inside the enclosure 12, the core 10 is surrounded by a metal inductor 16 with thermal insulation 18 being interposed between them. The core 10 is in the form of a vertical axis cylinder closed in sealed ~nne~ by a bottom wall lOa and by a removable top cover lOb.
Inside the chamber 14, the substrates to be densified are supported by a base turntable 20 capable of rotating about a vertical axis which coincides with the axis of the core 10 and of the inductor 16. Support trays 22 and 24 supported by the turntable 20 with interposed spacers 25 make it possible to load substrates at several levels, at least three in the example shown.
Rotation of the turntable 20 is controlled by a motor (not shown) coupled to a shaft 26 passing through the bottom wall of the enclosure 12 and through the bottom wall lOa of the core, and it is fixed to the bottom face of the turntable 20.
The gas for forming the matrix material which is to densify the substrates is admitted via a pipe 28 which leads to the top of the chamber 14, passing through the cover lOb. The gas comprises a mixture of a gaseous precursor for the matrix material together with HCl. The gaseous precursor depends on the nature of the matrix.
For an SiC matrix, the gaseous precursor is MTS together with H2. For a boron carbide matrix, the gaseous precursor is a mixture of BCl3 and a carbon precursor.
The carbon precursor may be an alkane, an alkyl, or an alkene, on its own or in a mixture, e.g. a mixture of C3H8 and of CH4 (or of natural gas). For a matrix constituted by an Si-B-C ternary system, the gaseous precursor is a mixture of MTS and BCl3 together with H2. The MTS, BCl3, C3H8 + CH4, Hz, and HCl gases come from sources 30, 31, 32, 33, and 34 via feed ducts 36, 37, 38, 39, and 40 provided with injection valves 42, 43, 44, 45, and 46 l~;ng to the pipe 28.
Residual gas is extracted from the chamber 14 by opening a valve 48 which puts the chamber 14 into communication with pumping apparatus 50 via at least one exhaust pipe 52. By way of example, the pumping apparatus 50 can be a water ring pump. The pipe 52 ~o~lln;cates with the bottom portion of the chamber 14 via an annular passage 54 formed around the shaft 26.
Signals delivered by a pressure sensor 56 and a temperature sensor 58 represent the pressure and the temperature in the chamber 14 and are transmitted to a controller 60. The controller controls the pump 50 and the valve 48 to establish the desired pressure in the chamber 14 prior to admitting the gas, and it controls a generator 62 feeding the inductor 16 so as to maintain the temperature inside the enclosure at the desired value. The controller 60 also controls the valves 42, 43, 44, 45, and 46 to control the respective flow rates of MTS, BCl3, CH4 + C3H8, H2, and HCl as a function of the predetermined composition of the gas.
The gas penetrating into the reaction chamber 14 comes initially into contact with a preheater 64, e.g. in the form of superposed perforated plates. Since the preheater plates are inside the reaction chamber, they are continuously at the temperature which obtains therein. This makes it possible to raise the gas to the desired temperature before it comes into contact with the substrates that are to be densified.
The volume situated around the core 10 inside the enclosure can be swept continuously by an inert gas such as nitrogen (Nz). This comes from a gas source 65 via a duct 66 provided with a valve 68 under the control of the controller 60. The nitrogen thus forms a blanket of inert gas around the reaction chamber. It is extracted via a duct 69 leading to the exhaust pipe 52 outside the enclosure 12.
Tests conc~ning chemical vapor infiltration of an SiC matrix have been performed with the above-described installation. During each test, on each of the three loading levels in the oven, there was placed the same set of porous substrates constituted by:
~ a cylindrical sample A comprising a needled carbon fiber texture having a diameter of 90 mm and a thickness of 35 mm;
~ three cylindrical samples B of the same texture, having a diameter of 35 mm and a height of 35 mm;
~ a cylindrical sample C of the same texture having a diameter of 15 mm and a height of 35 mm;
~ a cylindrical sample D of the same texture, having a diameter of 15 mm and a height of 8 mm; and ~ a sample E in the form of a cube having a side of about 2 cm3, and comprising a substrate of carbon fibers partially densified by vacuum suction of a powder.
The texture of samples A, B, C, and D was made by stacking and needling two~directional sheets of carbon fibers progressively, as described in document FR-A-2 584 106. The texture is identical to that constituting the preforms for the carbon-carbon composite material brake disks fitted to airplanes of the "Airbus"
type.
The substrate of sample E was constituted by a carbon fiber felt partially densified by vacuum suction of carbon powder, as described in document FR-A-2 671 797.
Each of the tests was performed at a pressure (P) in the reaction chamber of 10 kPa, with a ratio between the flow rates of H2 and of MTS (Q(H2) and Q(MTS)) equal to 6 for a total duration (d) of 20 hours (h).
A first series of three tests I, II, and III was performed at a temperature T in the reaction chamber of 1010~C, with Q(MTS) e~ual to 150 st~n~d cm3/min (sccm), and with Q(H2) equal to 900 sccm, while giving the HCl flow rates (Q(HCl)) of 0, 37.5 sccm, and 75 sccm respectively, i.e. proportions successively equal to 0, 25%, and 50~ of HCl flow rate relative to that of MTS.
A fourth test IV was performed by doubling Q(MTS) and Q(H2) compared with test III, leaving the other parameters unchanged.
A fifth test V was performed under the same conditions as test IV, except that the temperature T was lowered from 1010~C to 950~C.
A sixth test VI was performed under the same conditions as test V, with the exception of the HCl flow rate Q(HCl) being doubled from 75 sccm to 150 sccm.
In order to characterize the performance obt~; n~
concerning SiC densification of the substrates, the following characteristics were evaluated:
~the relative mass increase ~m/m of each substrate, ~m being the difference between the mass m' of the substrate at the end of the test (after densification) and the initial mass _ of the substrate;
~ longit~-~; n~ non-uniformity of densification (between the gas inlet and outlet), i.e. variation of densification as a function of the location of the substrates in the reaction chamber, evaluated for each type of substrate by measuring the ratio between the mass increase ~m/m at the "top" level (closest to the gas inlet) and the mass increase ~m/m at the "bottom" level (furthest from the gas inlet);
~ non-uniformity of infiltration, i.e. the gradient of densification between the core and the surface of each substrate evaluated by measuring the ratio between the mass uptake ~m/m of substrate A having the greatest volume and the mass uptake ~m/m of the substrate C having the smallest volume of substrates A, B, and C having the same nature and height, with this being done at the "top", "middle", and "bottom" levels of the reaction chamber;
~ the thickness of the SiC deposit on the fibers, evaluated by laser diffraction, to accuracy of the order of 0.1 ~; and ~ densification efficiency evaluated by calculating the ratio of the mass uptake actually achieved by the substrates to the total mass uptake that would theoretically be possible as a function of the quantity of MTS consumed.
The results obt~;n~ are brought together in Tables I to IV below.
TABLE I
Mass increase P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) 1010 1010 1010 1010 950 950 conditions Q(MTS)sccm150 150 150 300 300 300 Q(H2)sccm900 900 900 1800 1800 1800 Q(HCl)sccm 0 37.5 75 75 75 150 T33.131.1 22.8 57.3 36.2 32.3 A M 17.5 10.1 3.8 33.8 20.6 23.6 B 1.8 0.6 0.7 15.7 10.9 12.5 T 72.4 76 68.9 137 89 56.8 B M 27.1 25.8 16.6 54.7 34.1 33.4 B 4.4 0.9 1.3 32.2 20.2 21.1 T 113 110 111 208 134 68.6 Substrate C M 29.6 18.3 9.4 52.5 25 26.2 ~m/m(~) B 2.7 0.9 1.2 32.8 15.9 18.8 T 231 106.5 106 313 196 91.8 D M 29.6 18.3 4.1 123107.386.6 B 2.7 0.8 1.9 24.5 67.7 61 T 10.9 10.1 7.8 11.2 10 9.9 E M 1.4 0.9 1.7 6 10 8.5 B 0.2 1 1.4 0.5 6.8 7.5 Where the letters T, M, and B identify the "top", "middle", and "bottom" levels in the reaction chamber.
Clearly, the cycles performed by doublîng the MTS
and H2 flow rates gave rise to greater mass uptakes. The most uniform densifications were those performed at the lower temperature (950~C) in particular in the presence of HCl.
TABLE II
Longitudinal non-uniformity P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) 10101010 . 1010 .1010 ~ 950 950 conditions Q(MTS)sccm150 150 150 300 300 300 Q(H2)sccm900 900 900 18001800 1800 Q(HCl)sccm0 37.5 75 75 75 150 A18.451.832.6 3.6 3.3 2.6 B16.484.4 53 4.3 4.4 2.7 Substrates C 41.9 122.292.5 6.3 8.4 3.6 D 85.6133.1 55.812.8 2.9 1.5 E 54.5 10.1 5.622.4 1.5 1.3 The results ~om; n~ closest to the ideal optimum value (1) were for the cycle performed at doubled flow rates of MTS and H2, at the lower temperature and in the presence of HCl.
TABLE III
Densification non-uniformity _ P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) ,1010 10101010 .1010 950 . 950 conditions Q(MTS)sccm150 150 150 300 300 300 Q(Hz)sccm900 900 900 1800 1800 5 1800 Q(HCl)sccmO 37.5 75 75 75 150 T0.290.280.210.280.27 0.47 Level M 0.59 0.56 0.410.640.82 0.9 B 0.66 0.67 0.580.480.68 0.66 As before the best results were obt~i n~ with the cycle having doubled flow rates of MTS and H2, at low temperature, and in the presence of HCl.
TABLE IV
Efficiency P(kPa) 10 10 10 10 10 10 d(h) 20 20 20 20 20 20 Operating T(~C) 1010. 1010.1010. 1010 950 950 conditions Q(MTS)sccm 150 150 150 300 300 300 Q(H2)sccm 900 900 900 1800 1800 1800 Q(HCl)sccm 0 37.5 75 75 75 150 T 28.1 26.5 23.3 22.9 17 13 10 Level M 13 8.7 4.7 11.5 8 9 B 1.6 0.5 0.1 5.8 4.4 5.1 Total42.7 35.7 28.1 40.2 29.4 27.1 For cycles at doubled flow rates of MTS and H2, and at low temperature (950~C), the presence of HCl reduces efficiency, but it is better distributed throughout the load in the oven, and another point which is also important industrially, there were practically no unwanted deposits on the preheating plates.
The results brought together in the above tables ~ show conclusively the advantage in terms of reducing non-uniformity of SiC densification both throughout the volume of the oven and throughout the volume of a single part, and of performing chemical vapor infiltration at a relatively low temperature, preferably less than 100~C, in the presence of HCl, and with an increased flow rate of MTS.
The process of chemically infiltrating SiC vapor can be implemented with a temperature gradient, e.g. by means of an installation such as that shown diagrammatically in Figure 2.
This installation is more particularly designed for densifying annular preforms 100 such as the brake disk preforms made of a material that conducts heat, such as carbon in fiber form. The preforms are stacked around a central cylindrical graphite core 110 constituting a heater core, with the assembly being supported by a stationary insulating tray 120. The preforms 100 may be slightly spaced apart from one another by means of spacers 102 so as to facilitate access by the gas to the main faces of the preforms. The reaction chamber 114 in which the core and the preforms to be densified are received is defined by an insulating wall 118 that does not conduct electricity, having a bottom wall 118a and a cover 118b. An inductor 116 surrounds the wall 118, while still being inside an enclosure 112.
The means for f~;~g the chamber 114 with MTS + H2 + HCl gas and for extracting residual gas are similar to those of the installation of Figure 1 and they are not shown. Nevertheless, it may be observed that the exhaust pipe 152 leads directly to the bottom portion of the chamber 114 through the bottom wall 118a. In addition, the chamber 114 is not provided with means for preheating the incoming gas.
The core 110 is heated by electromagnetic coupling with the inductor 116. The annular preforms are heated by having their inside cylindrical surfaces in contact with the core 110. A temperature gradient is then established between these inside surfaces and the exposed outside surfaces thereof, which surfaces are cooled by radiation and by convection in contact with the gas that has penetrated into the chamber. This gradient depends in particular on the ~;me~ional and heat conductivity characteristics of the preforms. The generator 162 fee~; ng the inductor 116 is controlled so that, at least at the beg; nn; ng of the infiltration process, the temperature of preform portions adjacent to the core is significantly higher than the minimum temperature for SiC
deposition, i.e. about 700~C. SiC densification then takes place preferentially in those portions of the preforms. This prevents portions of the preforms close to their outside surfaces densifying too quickly, since that could lead to premature clogging of the pores, preventing densification in the cores of the preforms and r CA 02217702 1997-10-07 generating a steep densification gradient within the resulting parts.
The concept of performing chemical vapor infiltration with a temperature gradient is known. Here it constitutes a particularly advantageous application because of the presence of HCl in the gas, which presence has a particularly beneficial effect on the uniformity of the matrix.
In the installation of Figure 2, the substrates 100 are heated by means of the heater core 110 with which they are in contact. When the conductive nature of the substrates makes it possible (e.g. substrates made of carbon or graphite having a relatively high fiber content), it is possible to envisage heating the substrates at least in part by direct coupling with the inductor, in which case the core may optionally be omitted. Although the induced currents occur mostly in the vicinity of the surfaces of the substrates, the desired temperature gradient is established because the exposed surfaces of the substrates are cooled by radiation and convection.
The method of the invention is suitable for chemically infiltrating the vapor of a material made of carbon together with silicon and/or boron into any type of substrate capable of withstanding the operating conditions and chemically compatible with the gas. The method can be used to perform densification with a matrix constituted solely or partially of this material. In which case, the matrix may also include one or more matrix phases constituted by other materials deposited before and/or after the material made of carbon together with silicon and/or boron.
Claims (10)
1/ A method of chemically infiltrating vapor of a material comprising carbon together with silicon and/or boron within a porous substrate by means of a gas containing a gaseous precursor for said material, characterized in that infiltration is performed at a temperature not greater than 1050°C and the gas further includes hydrogen chloride (HCl).
2/ A method according to claim 1, characterized in that the volume proportion of HCl relative to the gaseous precursor for the silicon and/or the boron in the gas is not less than 25%.
3/ A method according to claim 1 or 2, characterized in that the chemical vapor infiltration is performed at a temperature of less than 1000°C.
4/ A method according to any one of claims 1 to 3, characterized in that the gaseous precursor comprises methyltrichlorosilane (MTS).
5/ A method according to claim 4, characterized in that the gaseous precursor further comprises a precursor for boron.
6/ A method according to claim 4 or 5, characterized in that the gas further comprises hydrogen (H2).
7/ A method according to any one of claims 1 to 6, characterized in that the gaseous precursor comprises a precursor for boron and a precursor for carbon.
8/ A method according to any one of claims 1 to 7, characterized in that a temperature gradient is established within the substrate so that its portions remote from its exposed surfaces present a temperature higher than that of said surfaces.
9/ A method according to claim 8, for densifying substrates of annular shape, characterized in that the substrate is placed around a heater core with which it is in contact, the substrate being heated by contact with the core itself heated by coupling with an inductor.
10/ A method according to claim 8, characterized in that the substrate is made of a conductive material and is heated by induction, at least partially, by direct coupling with an inductor.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR95/04381 | 1995-04-12 | ||
FR9504381A FR2732962B1 (en) | 1995-04-12 | 1995-04-12 | PROCESS FOR CHEMICAL VAPOR INFILTRATION OF A MATERIAL COMPOSED OF CARBON AND SILICON AND / OR BORON |
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Publication Number | Publication Date |
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CA2217702A1 true CA2217702A1 (en) | 1996-10-17 |
Family
ID=9478032
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Application Number | Title | Priority Date | Filing Date |
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CA002217702A Abandoned CA2217702A1 (en) | 1995-04-12 | 1996-04-12 | Method for the chemical vapour infiltration of a material consisting of carbon and silicon and/or boron |
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Country | Link |
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EP (1) | EP0820424B1 (en) |
JP (1) | JPH11503493A (en) |
CA (1) | CA2217702A1 (en) |
DE (1) | DE69609411T2 (en) |
FR (1) | FR2732962B1 (en) |
RU (1) | RU2158251C2 (en) |
WO (1) | WO1996032360A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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NL2002126C2 (en) * | 2007-10-25 | 2010-06-07 | Ardenne Anlagentech Gmbh | DIFFUSION OVEN AND METHOD FOR TEMPERATURE GUIDANCE. |
US10167549B2 (en) | 2014-02-17 | 2019-01-01 | Ihi Corporation | Heat-resistant composite material production method and production device |
US10221104B2 (en) | 2014-02-25 | 2019-03-05 | Ihi Corporation | Heat-resistant composite material production method and production device |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
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DE19646094C2 (en) * | 1996-11-08 | 1999-03-18 | Sintec Keramik Gmbh | Process for chemical gas phase infiltration of refractory substances, in particular carbon and silicon carbide, and use of the process |
FR2950622B1 (en) * | 2009-09-28 | 2011-10-21 | Snecma Propulsion Solide | PIECE OF COMPOSITE MATERIAL WITH CERAMIC MATRIX AND METHOD FOR MANUFACTURING THE SAME |
DE102012100176B4 (en) | 2012-01-10 | 2016-11-17 | Cvt Gmbh & Co. Kg | A method of chemical vapor infiltration of at least one refractory |
FR3007511B1 (en) * | 2013-06-19 | 2017-09-08 | Herakles | INSTALLATION FOR THERMAL TREATMENTS OF PRODUCTS IN COMPOSITE MATERIAL COMPRISING DELOCALIZED TEMPERATURE MEANS |
RU2638610C2 (en) * | 2016-03-29 | 2017-12-14 | Общество с ограниченной ответственностью "Оптогард Нанотех" (ООО "Оптогард Нанотех)" | Device for laser-plasma synthesis of high-solid micro- and nanostructured coatings |
FR3059679B1 (en) * | 2016-12-07 | 2021-03-12 | Safran Ceram | CONFORMATION TOOLS AND PLANT FOR CHEMICAL GAS INFILTRATION OF FIBROUS PREFORMS |
FR3095213B1 (en) * | 2019-04-19 | 2022-12-23 | Safran Ceram | CVI densification plant |
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FR2594119B1 (en) * | 1986-02-10 | 1988-06-03 | Europ Propulsion | INSTALLATION FOR CHEMICAL VAPOR INFILTRATION OF A REFRACTORY MATERIAL OTHER THAN CARBON |
FR2668477B1 (en) * | 1990-10-26 | 1993-10-22 | Propulsion Ste Europeenne | REFRACTORY COMPOSITE MATERIAL PROTECTED AGAINST CORROSION, AND METHOD FOR THE PRODUCTION THEREOF. |
-
1995
- 1995-04-12 FR FR9504381A patent/FR2732962B1/en not_active Expired - Fee Related
-
1996
- 1996-04-12 CA CA002217702A patent/CA2217702A1/en not_active Abandoned
- 1996-04-12 WO PCT/FR1996/000561 patent/WO1996032360A1/en active IP Right Grant
- 1996-04-12 EP EP96913580A patent/EP0820424B1/en not_active Expired - Lifetime
- 1996-04-12 JP JP8530779A patent/JPH11503493A/en active Pending
- 1996-04-12 DE DE69609411T patent/DE69609411T2/en not_active Expired - Lifetime
- 1996-04-12 RU RU97118434/03A patent/RU2158251C2/en not_active IP Right Cessation
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL2002126C2 (en) * | 2007-10-25 | 2010-06-07 | Ardenne Anlagentech Gmbh | DIFFUSION OVEN AND METHOD FOR TEMPERATURE GUIDANCE. |
US10167549B2 (en) | 2014-02-17 | 2019-01-01 | Ihi Corporation | Heat-resistant composite material production method and production device |
US10221104B2 (en) | 2014-02-25 | 2019-03-05 | Ihi Corporation | Heat-resistant composite material production method and production device |
Also Published As
Publication number | Publication date |
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EP0820424B1 (en) | 2000-07-19 |
JPH11503493A (en) | 1999-03-26 |
WO1996032360A1 (en) | 1996-10-17 |
DE69609411D1 (en) | 2000-08-24 |
FR2732962B1 (en) | 1997-07-04 |
FR2732962A1 (en) | 1996-10-18 |
DE69609411T2 (en) | 2001-03-01 |
EP0820424A1 (en) | 1998-01-28 |
RU2158251C2 (en) | 2000-10-27 |
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