JPH06321652A - Heat-resistant composite member - Google Patents

Abstract

PURPOSE:To use a heat-resistant composite member for a long time by repairing a damaged part of the specified base material with a source material containing a metal source which can be maintained in a gas state at high temp. and can be changed into ceramic. CONSTITUTION:Continuous pores 2h are formed to penetrate from the surface 2a to the back surface 2b of a porous base material 2 such as SiC, and the surface 2a is coated with a heat-resistant oxide coating layer 3 having sealing property. Then the back surface 2b is attached to a jacket 5 having a vacancy 4, surface 5a, hole 5ha and hole 5hb to produce a heat-resistant composite member 1. When cracks 8 generate in the coating layer 3 during the time when the member 1 is used at high temp., the vacancy 4 is filled with the source material for repairment maintained in a gas state at high temp. and high pressure. This source material passes through pores 2h to the cracks 8 to break the equibillium state in the vacancy 4 and to proceed pyrolysis and/or chemical reaction of the source material. Thus, ceramics 9 is precipitated to cover and seal cracks 8.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat resistant composite member,
In particular, the present invention relates to a heat-resistant composite member improved for long-term use in a high-temperature oxidizing atmosphere or a high-temperature reducing atmosphere.

[0002]

2. Description of the Related Art As a high temperature equipment such as a nozzle liner of a jet engine, a gas turbine or a rocket engine, or a high temperature part structural material such as a furnace wall material of a high temperature furnace, a heat resistant steel such as a heat resistant steel to which an alloying element such as Cr is added is used. Alloy or Ni base and C
A super heat-resistant alloy or the like made of an alloy with an o-base is used.

Further, as a high temperature part structural material, a base material such as a metal base material having heat resistance is further exposed to the high temperature side of the base material in order to impart heat resistance, oxidation resistance or heat insulation. Side surface (hereinafter, the term "front surface" as used herein means the surface on the side exposed to the hot side of the substrate, and "back surface" refers to the side exposed to the hot side of the substrate). Application of a heat-resistant composite member in which a ceramic layer is coated (meaning the surface on the other side of the surface) is being studied. For high-temperature equipment that uses a heat-resistant composite material with a ceramics layer coated on the surface of the base material, if the ceramics layer is damaged during use at high temperatures, replace the high-temperature equipment with damaged ceramics layer with the parts. Alternatively, it is necessary to maintain the performance of the high-temperature equipment or the like by performing maintenance work such as coating the ceramic layer again on the damaged portion of the ceramic layer.

Further, in reality, the high temperature portion structural material is often used in a portion where maintenance work such as recoating the ceramic layer is difficult. Therefore,
The conventional high-temperature equipment using the high-temperature structural material has a problem that its product life is determined by the time during which the high-temperature structural material can be used in a high-temperature atmosphere.

Further, in the conventional high temperature equipment using the high temperature part structural material, the high temperature part structural material is continuously used for a long time without performing maintenance work beyond the usable time of the high temperature part structural material in a high temperature atmosphere. There was a problem that it could not be used in an atmosphere.

As a technique for alleviating such a problem, a technique having an internal structure for cooling the high temperature structural material has been developed. However, the heat-resistant member having such a mechanism for cooling the high-temperature-part structural material has a problem that the structure itself of the heat-resistant member becomes complicated, which is still insufficient.

As the high temperature portion structural material, the high temperature portion structural material itself or the ceramic coating material of the ceramic layer formed on the surface of the base material is oxidized in a high temperature atmosphere in order to improve oxidation resistance. A so-called self-repairing high temperature part structural material, to which a substance that produces a glassy substance by this is added, is known. However, although such a self-repairing high temperature part structural material has a slightly extended use period in a high temperature atmosphere, the above effect disappears when the added substance is lost, and it is still a consumable material requiring maintenance. It had the drawback of not having it.

In the conventional high-temperature equipment using the high-temperature structural material, it is assumed that the high-temperature structural material is naturally damaged or consumed, and the development of how to reduce the rate of the damage or consumption is advanced. It was just being done.

[0009]

As described above, since a high temperature part structural material that can be used at a high temperature for a long time has not been substantially developed in the past, in a high temperature device or the like using the conventional high temperature part structural material, Regular maintenance was required.

The inventors of the present invention, as a related art particularly interested in this application, as a high-temperature part structural member that can be used for a long time without requiring maintenance in a high-temperature oxidizing atmosphere, as a related art, Japanese Patent Application No. 4-205359. Proposed the invention described in.

The heat and oxidation resistant material described in Japanese Patent Application No. 4-205359 is provided on the back side of a porous base material having heat resistance and having continuous pores penetrating the front and back surfaces. And a liquid substance made of at least one kind of heat-resistant ceramics precursor polymer compound such as polysilazane, polycarbosilane, polysiloxane, and polysilastyrene contained in the liquid substance supply unit. .

In the invention described in Japanese Patent Application No. 4-205359, when the porous base material or the heat resistant and oxidation resistant layer provided on the surface of the porous base material is damaged during use at high temperature, The liquid substance has the advantage that it can flow out of the damaged portion through the continuous pores, become heat resistant ceramics at high temperature, and cover the damaged portion.

In addition, the invention described in Japanese Patent Application No. 4-205359 has an advantage that it is not necessary to perform maintenance for a long period of time because the consumed amount of the liquid substance is supplied from the outside.

However, in the invention described in Japanese Patent Application No. 4-205359, since the liquid substance is used as the raw material of the repair material for covering the damaged part, the pore diameter is small and / or the porosity is small. For a qualitative substrate, there has been a problem that the liquid substance is not sufficiently supplied from the rear surface side to the front surface side of the substrate through the pores, and the damaged portion is not sufficiently repaired. Further, the liquid substance supplied from the back surface side of the base material is exposed to a high-temperature atmosphere in the pores of the base material, so that it is thermally decomposed and turned into ceramics, resulting in clogging in the pores. There is a problem that the substance is not sufficiently supplied to the damaged part. Also, Japanese Patent Application No. 4-20
In the invention described in 5359, as a result of using the liquid substance, there is a problem that a device for forcibly injecting the liquid substance from the back surface to the front surface of the base material under pressure is required.

The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a heat-resistant composite member that can be used for a long time in a high-temperature atmosphere without maintenance, and further to provide a porous base material having a small pore diameter and / or porosity. Even if you use
The heat-resistant and oxidation-resistant layer formed on the surface of the base material and / or the damaged portion of the heat-resistant layer can be sufficiently repaired, and clogging is less likely to occur in the pores of the porous base material. An object of the present invention is to provide a heat-resistant composite member that does not require the use of a device for permeating the restorative material from the back surface of the base material under pressure.

[0016]

A heat resistant composite member according to a first aspect of the present invention is a porous substrate having a front surface and a back surface, having heat resistance, and having continuous pores penetrating the front surface and the back surface. And a heat-resistant and oxidation-resistant layer having airtightness formed so as to cover the surface of the base material, a sealing means provided on the back surface side of the base material, and the heat- and oxidation-resistant layer which is housed in the sealing means and has a high temperature. When it is damaged during use, the raw material of the restoration material flows through the continuous pores, flows out from the damaged portion, and covers the damaged portion. It includes a metal source capable of maintaining a state and being exposed to a high temperature to form a ceramic.

The raw material of the restoration material preferably further contains a carbon source capable of maintaining a gaseous state at high temperature.

The heat resistant composite member according to the second invention is
A porous base material having a front surface and a back surface, having heat resistance, and having continuous pores penetrating the front surface and the back surface,
The heat-resistant layer having airtightness formed so as to cover the surface of the base material, the sealing means provided on the back surface side of the base material, and the heat-resistant layer housed in the sealing means and damaged during use at high temperature. In this case, the raw material of the restoration material, which flows through the continuous pores, flows out from the damaged portion, and covers and closes the damaged portion, the raw material of the restoration material can hold a gas state at a high temperature in the sealing means, and Contains a carbon source capable of carbonization when exposed to high temperatures.

[0019]

The heat resistant composite member according to the first aspect of the present invention has the following structure.

(1) A porous base material having continuous pores penetrating the front surface and the back surface is provided.

(2) A heat-resistant and oxidation-resistant layer having airtightness is formed so as to cover the surface of the base material.

(3) A sealing means provided on the back side of the base material. (4) A raw material of a restoration material containing a metal source that is housed in the sealing means, can maintain a gas state at high temperature, and is exposed to high temperature and can be made into ceramics.

When the heat and oxidation resistant layer is not damaged, the above (1), (2) and (3) form a closed space.

The metal source added as one component of the raw material of the restoration material contained in the sealing means becomes a gas state at a high temperature. Part of the metal source in the gas state is thermally decomposed,
Further, a chemical reaction occurs with other raw material added as a raw material of the restoration material, and a partially activated metal source or a part thereof is made into ceramics.

In the closed space constituted by the above (1), (2) and (3), the unreacted metal source, the activated metal source, the fine particles of the ceramicized restoration material, and the reaction formation Gas etc. are in equilibrium. The ceramicized fine particles are almost floating.

Particularly, on the surface on the high temperature side, the rate of decomposition and chemical reaction of the metal source is large, but within the sealing means, the decomposition and chemical reaction of the metal source do not proceed so much because the temperature is relatively low. In addition, since the inert reaction product gas exists near the surface on the high temperature side, the raw material of the restoration material does not flow much into the vicinity of the surface on the high temperature side.

The raw material of the restoration material expands in volume in a high temperature atmosphere due to thermal expansion or vaporization, and is maintained in a high pressure state in the closed space.

When the heat-resistant and oxidation-resistant layer is damaged at the time of use at high temperature, the raw material of the repair material, which is kept in a gas state at high temperature, flows out from the damaged portion through the continuous pores of the porous base material. At the same time, the equilibrium state of the raw material of the restorative material, which was in the equilibrium state in the above-mentioned closed space, is broken, thermal decomposition and / or chemical reaction of the raw material of the restorative material proceeds, and ceramics are deposited on the damaged portion. , Repair the damaged part by covering the damaged part.

When a carbon source capable of maintaining a gas state at a high temperature is further included as a raw material of the restoration material, a metal source capable of ceramization and a carbon source cause a chemical reaction to contain carbon. Ceramics containing non-oxide ceramics as a main component are deposited on the damaged portion. Since non-oxide ceramics have higher thermal shock resistance and higher mechanical strength than oxide ceramics, they are suitable as materials for repairing damaged parts.

The heat resistant composite member according to the first invention can be used in a high temperature oxidizing atmosphere or a high temperature reducing atmosphere. Then, the raw material of the restoration material may be supplied to the inside of the sealing means in advance and / or to the inside of the sealing means from the outside.

Therefore, the heat resistant composite member according to the first invention can be used in a high temperature oxidizing atmosphere for a long time or in a high temperature reducing atmosphere for a long time.

In the heat resistant composite member according to the first invention,
When the restorative material is non-oxide ceramics, the non-oxide ceramics in the restorative material chemically react with oxygen in the air to form oxide-based ceramics on the surface side of the restorative material, which results in oxidation resistance. Is given.

The heat resistant composite member according to the second invention is
It is intended to be used in a high temperature reducing atmosphere for a long time. The heat-resistant composite member according to the second aspect of the invention includes, as a raw material of the restoration material, a carbon source capable of maintaining a gas state at a high temperature. Therefore, when the heat resistant composite member according to the second invention is used in a high temperature reducing atmosphere, the carbon source capable of maintaining a gas state at a high temperature is carbonized in the reducing atmosphere to form carbon (graphite).
The refractory material deposits on the damaged area and the damaged area is covered and blocked. Carbonaceous refractories are generally excellent in thermal shock resistance and corrosion resistance.

The heat resistant composite member according to the second invention is
Since it is used in a high-temperature reducing atmosphere as described above, it is sufficient that the layer having airtightness formed on the surface side of the base material has heat resistance.

The heat resistant composite member according to the second invention is
The configuration is the same as that of the first invention except that the heat-resistant layer having airtightness formed on the front surface side of the base material and the carbon source as a raw material of the restoration material are included.

Therefore, the heat resistant composite member according to the second invention can be used in a high temperature reducing atmosphere for a long time.

Further, in the heat-resistant composite member according to the first and second aspects of the invention, the raw material of the restoration material supplied from the back surface side of the base material is quickly in a gas phase state in the pores of the base material under a high temperature atmosphere. Since it passes through, pores are less likely to be clogged.

In the heat-resistant composite member according to the first and second aspects of the present invention, the raw material of the restoration material supplied from the back surface side of the base material is quickly in a gas phase state in the pores of the base material under a high temperature atmosphere. Since it passes through, the raw material of the restoration material can be sufficiently supplied to the damaged portion even if the pore diameter of the base material is reduced.

[0039]

EXAMPLES Examples of the present invention will be shown below, but the following examples are used only for explaining the present invention, and the present invention is not limited by the following examples. Not a thing.

FIG. 1 is a schematic view schematically showing a specific example of the heat resistant composite member according to the present invention. Referring to FIG. 1, the heat resistant composite member 1 shows a heat resistant composite member used as a pilot test for confirming the effect of the present invention.
A porous base material 2, a coating layer (dense layer) 3 formed so as to cover the front surface 2a of the base material 2, and a jacket 5 having a hollow portion 4 provided on the back surface 2b side of the base material 2. including.

The porous substrate 2 is made of a heat-resistant material and has continuous pores 2h penetrating the front surface 2a and the back surface 2b.

The coating layer 3 is formed of a heat resistant and oxidation resistant material having airtightness. On the surface 5a side of the jacket 5, there is a hole 5h for supplying the raw material of the restoration material to the base material 2 side.
a is provided. On the other hand, on the back surface 5b side of the jacket 5, a hole 5h for supplying the raw material of the restoration material to the hollow portion 4 is formed.
b is provided. The hole 5hb is provided with, for example, a valve (not shown) and has a structure capable of opening and closing the hole 5hb.

The hole 5hb is connected to a restoration material raw material storage tank (not shown). The hollow portion 4 has a structure in which it is sealed by the base material 2, the coating layer 3, and the jacket 5.

The raw material of the restorative material is always supplied from the outside into the hollow portion 4 through the hole 5hb of the jacket 5 when the heat resistant composite member 1 is used at high temperature.

The raw material of the restorative material is in a gas state and maintained in a high pressure state in the hollow portion 4 when the heat resistant composite member 1 is used at high temperature.

Next, the working mechanism of the heat-resistant composite member 1 will be described below with reference to FIG.

It is assumed that the heat resistant composite member 1 is used at a high temperature and cracks 8 occur in the coating layer 3. When the crack 8 is generated in the coating layer 3, the raw material of the restoration material, which is in a gas state at a high temperature and is maintained in a high pressure state in the hollow portion 4, passes through the continuous pores 2h of the porous substrate 2. At the same time as flowing out from the crack 8, the equilibrium state of the raw material for the restoration material, which was in the equilibrium state in the hollow portion 4, collapses,
The thermal decomposition and / or chemical reaction of the raw material of the restoration material progresses, the ceramics 9 is deposited in the cracks 8, and the cracks 8
Is covered and blocked.

Next, description will be made using concrete experimental data. Example 1 As the porous base material 2, a SiC base material having continuous through holes from the front surface 2a to the back surface 2b was prepared. This SiC substrate has a porosity of 50% and a thickness of 10 m.
It had a disk shape of m and a diameter of 50 mm.

Next, as a coating layer 3, a known chemical vapor deposition method (C
VD) to form an airtight SiC layer with a thickness of about 200μ
It was deposited to a film thickness of m. Further, for the purpose of preventing oxidation from the side surface of the SiC base material, the side surface of the SiC base material was also coated with a SiC layer having a film thickness of about 200 μm. By this operation, the opening portion of the continuous through-hole opening on one surface of the SiC base material was almost completely sealed by the SiC layer having airtightness.

Next, cracks in the SiC layer were sealed with borosilicate glass. Next, about 1.0 kg of a mixed gas containing silicon tetrachloride (SiCl ₄ ), methane (CH ₄ ), and hydrogen (H ₂ ) as a carrier gas is used as a raw material of the restoration material.
It was injected through the hole 5hb of the jacket 5 at a pressure of / cm ² .

The composition ratio of the mixed gas is silicon tetrachloride (Si
The molar ratio of Cl ₄ ), methane (CH ₄ ) and hydrogen (H ₂ ) was adjusted to 4: 4: 1.

In this embodiment, after the raw material of the restorative material was supplied into the hollow portion 4, the hole 5hb of the jacket 5 was closed.

Example 2 As the porous base material 2, a C / SiC composite base material having continuous through holes from the front surface 2a to the back surface 2b was prepared. This C / SiC composite substrate had a porosity of about 40%, a disc shape with a thickness of 10 mm and a diameter of 50 mm.

Next, on one surface of the C / SiC composite base material, which is the surface 2a side, by using a known chemical vapor deposition (CVD) method as the coating layer 3, SiC having airtightness is formed.
The layer was deposited to a thickness of about 200 μm. In addition, C / Si
For the purpose of preventing oxidation from the side surface of the C composite base material, the side surface of the C / SiC composite base material also has about 20
A 0 μm thick SiC layer was coated. By this operation, the opening of the continuous through-hole opening on one surface of the C / SiC composite substrate was almost completely sealed by the SiC layer having airtightness.

Next, cracks in the SiC layer were sealed with borosilicate glass. Next, about 1.0 kg of a mixed gas containing titanium tetrachloride (TiCl ₄ ), methane (CH ₄ ), and hydrogen (H ₂ ) as a carrier gas was used as a raw material of the restoration material.
It was injected through the hole 5hb of the jacket 5 at a pressure of / cm ² .

The composition ratio of the mixed gas is titanium tetrachloride (Ti
Cl _4), methane (CH _4), the molar weight ratio of the hydrogen _{(H 2), 4: 4} : was adjusted to 1.

In this embodiment, after the raw material of the restorative material was supplied into the hollow portion 4, the hole 5hb of the jacket 5 was sealed.

Comparative Example 1 The same SiC substrate as in Example 1 was prepared. Next, in the same manner as in Example 1, an SiC layer having airtightness was formed on one surface of the SiC substrate, which was the front surface side, by using known CVD to about 20.
It was deposited to a film thickness of 0 μm. Further, for the purpose of preventing oxidation from the side surface of the SiC base material, etc., the side surface of the SiC base material was also coated with a SiC layer having a thickness of about 200 μm. Next, the cracks in the SiC layer were sealed with borosilicate glass.

Next, the hole 5hb of the jacket 5 was sealed without injecting the raw material of the restoration material into the hollow portion 4.

Comparative Example 2 The same C / SiC composite substrate as in Example 2 was prepared. Next, in the same manner as in Example 2, a known CVD was used to deposit an airtight SiC layer with a thickness of about 200 μm on one surface of the C / SiC composite substrate. Further, for the purpose of preventing oxidation from the side surface of the C / SiC composite base material, the side surface of the C / SiC composite base material was coated with a SiC layer having a thickness of about 200 μm. Next, the cracks in the SiC layer were sealed with borosilicate glass.

Next, the hole 5hb of the jacket 5 was sealed without injecting the raw material for the restoration material into the hollow portion 4.

Next, a heat and oxidation resistance test was conducted on each of Examples 1 and 2 and Comparative Examples 1 and 2.

The heat and oxidation resistance test was conducted under the following conditions. Sample shape: thickness x diameter = 10 mm x φ50 mm Heating method: flame with a hydrocarbon containing excess oxygen (heating region φ10
mm, about 1500 ° C.) Heating time: 1 hour As a result of the above-mentioned test, the results shown in Table 1 below were obtained.

[0064]

[Table 1]

In Table 1, the evaluation was carried out by measuring the concave portion of the heating surface before and after the test (the initial plane is the reference point 0, and the concave portion is positive).

Referring to Table 1, in Comparative Example 1, the SiC layer having airtightness and the porous SiC base material were partially burned off, and the tungsten base used as the jacket 5 was exposed. It was Moreover, in Comparative Example 2, the SiC layer having airtightness and the porous C / SiC composite base material were partially disappeared, and the tungsten base used as the jacket 5 was exposed.

On the other hand, in Example 1, the restoration material is selectively applied to the surface of the SiC base material through the continuous pores of the SiC base material from the portion of the SiC layer formed on the surface of the SiC base material that has been burned down by heating. It was observed that the raw material gas of (3) flowed out and the ceramics containing SiC as a main component covered and closed the damaged portion. Further, the ceramics containing SiC as a main component that covers the damaged portion was oxidized on the surface side in a high temperature oxidizing atmosphere to form a glassy substance containing SiO ₂ as a main component. Ceramics containing SiC as a main component have excellent thermal shock resistance, and ceramics containing SiC as a main component have been given oxidation resistance by being oxidized on the surface.

In Example 2, the restoration material was selectively removed from the portion of the SiC layer formed on the surface of the C / SiC composite substrate which was burned down by heating, through the continuous pores of the C / SiC composite substrate. Raw material gas flows out and TiC
It was observed that the ceramics containing as a main component covered and covered the damaged part. Also, Ti covering and covering the damaged part
The ceramics containing C as a main component were oxidized on the surface side in a high temperature oxidizing atmosphere to form oxide ceramics containing TiO ₂ as a main component. The ceramic containing TiC as a main component has excellent thermal shock resistance, and the ceramic containing TiC as a main component is endowed with oxidation resistance by oxidizing the surface thereof.

It should be noted that the disclosure of the above embodiments is merely specific examples of the present invention and does not limit the technical scope of the present invention.

In the first invention, the material of the porous base material having a front surface and a back surface, having heat resistance, and having continuous pores penetrating the front surface and the back surface is Si.
Non-oxide ceramic materials such as C, Si ₃ N ₄ , ZrC and HfC, oxide ceramic materials such as ZrO ₂ , Al ₂ O ₃ and mullite ceramics, carbon, or
Examples thereof include metals that can be used as heat resistant materials such as W, Mo, Ta, and Nb. Such materials may be used alone or in combination of two or more.

The term "having heat resistance" as used in the present specification means that it has heat resistance and high strength,
Although not particularly limited to the following cases, for example,
It means high strength at about 1000 ° C or higher. More specifically, although not particularly limited to the following cases,
For example, the heat resistant temperature of the porous base material may be 1000 ° C., and the heat resistant temperature of the heat resistant composite member according to the present invention is about 1500 ° C. or more and 2200 ° C. or less.

The term "continuous pores penetrating the front surface and the back surface" used in the present specification means penetrating pores through which a fluid can pass.

The form of the porous base material may be, for example, one having a sponge structure such as a foam metal or a sintered body of fine metal particles, or a fiber reinforced such as C / C composite. It may be a composite member. Further, in an extreme case, it may be a sintered body of fibers.

The porosity and pore diameter of the base material are determined by the raw materials of the base material and the restorative material, the conditions of use, and the purpose of use.
The pore size is not particularly limited to the following cases,
For example, the average pore diameter is preferably about 0.1 μm or more and 100 μm or less.

The material of the heat-resistant and oxidation-resistant layer having airtightness, which is formed so as to cover the surface of the base material, is Si.
Non-oxide ceramic materials such as C, Si ₃ N ₄ , ZrC, HfC, or SiO ₂ , ZrO ₂ , Al ₂ O ₃
An oxide-based ceramic material or the like can be used. The heat-resistant and oxidation-resistant layer is preferably a dense layer, that is, a heat-resistant and oxidation-resistant layer having a low air permeability, in order to prevent unnecessary outflow of the raw material of the restorative material. When a porous body is used as the heat-resistant and oxidation-resistant layer, it is preferable that the pores are generally formed by closed pores or inlet pores that have an entrance but no exit. The porosity and pore size of the heat-resistant and oxidation-resistant layer are determined by the porous base material, the raw material of the restorative material, and / or the use conditions.

As the sealing means provided on the back surface side of the base material, a porous base material having a sealed hollow portion,
Alternatively, a structure having an outer wall material and an inner wall material, the inner wall material being formed of a porous base material, and a space sealed by the outer wall material and the inner wall material being formed, for example, a sandwich structure, etc. You can

In addition, when the heat-resistant and oxidation-resistant layer is housed in the sealing means and damaged during use at high temperatures, the raw material of the restoration material for flowing out from the damaged portion through continuous pores and covering the damaged portion. As the above, a metal source capable of maintaining a gas state at a high temperature in the sealing means and capable of being formed into a ceramic by being exposed to a high temperature can be used.

The metal source is not particularly limited to the following cases, but metal halides and the like can be mentioned. As a metal halide source, silicon tetrachloride (SiCl ₄ ), disilicon hexachloride (Si ₂ Cl ₆ )
Etc., silicon chloride represented by the general formula Si _n Cl _{2n + 2} , titanium trichloride (TiCl ₃ ), titanium tetrachloride (TiCl ₄ ).
And the like, such as titanium chloride.

By the way, silicon chloride (Si _n Cl _{2n + 2} )
The boiling point of is generally represented by the following formula.

Ts (K) = 81.5n + 249 Therefore, when silicon chloride is used as the metal source,
Depending on the purpose of use, the metal source of the restorative material can be selected according to the above formula.

As the raw material of the restoration material, the above-mentioned metal sources can be used alone or together with a carrier gas such as hydrogen (H ₂ ) gas.

The raw material of the restoration material preferably further contains a carbon source capable of maintaining a gas state at a high temperature. Hydrocarbons can be mentioned as such a carbon source. The hydrocarbon may be a saturated hydrocarbon or an unsaturated hydrocarbon. Saturated hydrocarbons include methane (CH ₄ ),
Ethane (C ₂ H _6), mention may be made of propane (C ₃ H _8), also, ethylene (C ₂ H ₄₎ as the unsaturated hydrocarbons, propylene (C ₃ H _6), acetylene (C ₂ H ₂ ) and the like.

As a raw material for the restoration material, a metal source capable of maintaining a gas state at a high temperature in the sealing means and capable of forming a ceramic by being exposed to a high temperature, and carbon capable of maintaining a gas state at a high temperature in the sealing means. The inclusion of the source is preferable for the following reasons.

That is, in the case where the above-mentioned metal source and the above-mentioned carbon source are included, each of the metal source and the carbon source is thermally decomposed by being exposed to a high temperature, or by a chemical reaction, at a damaged portion, for example, , SiC and Ti
Non-oxide ceramics containing C as a main component are deposited.
This is because such non-oxide ceramics such as SiC and TiC are more excellent in thermal shock resistance and mechanical strength than oxide ceramics containing SiO ₂ or TiO ₂ as a main component. Then, in non-oxide ceramics such as SiC and TiC, the surface side thereof is oxidized in a high temperature oxidizing atmosphere to become oxide ceramics, and in addition to thermal shock resistance, excellent mechanical properties, oxidation resistance is imparted. It On the other hand, when a metal source and / or a raw material containing a metal source and a carrier gas is used as the raw material of the restoration material, oxide-based ceramics are directly deposited on the damaged portion. The characteristics are lower than those of non-oxide ceramics.

The metal source capable of maintaining a gas state at a high temperature in the sealing means and capable of being made into ceramic by being exposed to a high temperature may be a gas, a liquid or a solid at room temperature. When using a metal source that is liquid or gas at room temperature, the heat of vaporization when it becomes a gas at high temperature causes
It exerts the action of cooling the porous base material.

The ceramics produced from the above metal source and / or carbon source have the same heat resistance (melting point, decomposition point, sublimation point, etc.) and oxidation resistance as those of the porous substrate, or It is preferably lower than that of the porous substrate. Before the porous base material is consumed in a high temperature oxidizing atmosphere, when the porous base material has higher heat resistance and oxidation resistance than the ceramics generated from the metal source and / or the carbon source. In addition, when the heat-resistant and oxidation-resistant layer is damaged during use at high temperature, the raw material of the restoration material flows out from the damaged part through continuous pores and covers the damaged part, so that the prototype of the porous base material is used. Because it is held.

Further, the amount and composition of the raw material of the restoration material housed in the sealing means and the permeation injection pressure of the raw material of the restoration material in the gaseous state inside the sealing means at high temperature are determined by the porous base material and the heat-resistant composite material. It is determined according to the purpose of use of the member and is not particularly limited.

The raw material of the restoration material may be stored in advance in the sealing means, or the restoration material such as a cylinder provided outside the sealing means may be stored in the sealing means. It may be supplied from the raw material storage means.

Further, the raw material of the restorative material does not necessarily have to be a gas at room temperature and may be a liquid or a solid. In this case, heat is introduced from the outside into the sealing means at a temperature at which the porous base material is not significantly damaged,
If the raw material of the restoration material is vaporized, the heat of vaporization can be used for cooling the porous base material, and the gas state in the sealing means due to the volume expansion when the raw material of the restoration material becomes gas. When the pressure of the raw material of the restorative material is increased and the heat-resistant and oxidation-resistant layer is damaged, the raw material of the restorative material in a gas state can be selectively and efficiently discharged to the damaged portion.

Further, the heat resistant composite member according to the second invention is
It is used in a high-temperature reducing atmosphere, and the material of the heat-resistant composite member according to the above-mentioned first invention can be preferably used. Further, in the second invention, the layer having airtightness formed on the surface of the porous substrate is not required to have oxidation resistance, so that a heat-resistant layer having airtightness is preferably used. You can As a material for such a heat resistant layer, for example, a carbonaceous refractory can be used in addition to the material for the heat resistant and oxidation resistant layer that can be used in the first invention. Further, as a raw material of the restoration material, a carbon source which can maintain a gas state at a high temperature in the sealing means and can be carbonized by being exposed to the high temperature can be used. The carbon source is not particularly limited as long as it is carbonized by thermal decomposition and / or reduction reaction in a high temperature reducing atmosphere. Examples of such carbides include hydrocarbons. The hydrocarbon may be a saturated hydrocarbon or an unsaturated hydrocarbon. Examples of the saturated hydrocarbon include methane (CH ₄ ), ethane (C ₂ H
₆ ) or propane (C ₃ H ₈ ), and the unsaturated hydrocarbon may be ethylene (C ₂ H _2).
H ₄ ), propylene (C ₃ H ₆ ), acetylene (C ₂ H
₂ ) etc. can be mentioned.

[0091]

The heat-resistant composite member according to the first aspect of the present invention has the above-described structure. As a result, by supplying the raw material of the restoration material from the outside, for example, in a high temperature oxidizing atmosphere and / or a high temperature reducing atmosphere, It can be used continuously for a long time without maintenance.

Further, the other heat-resistant composite member according to the first aspect of the present invention can maintain a gaseous state at a high temperature as a raw material for a restorative material,
Moreover, as a result of using the metal source which is exposed to high temperature and can be made into ceramics, it is possible to prevent clogging of the porous substrate in the continuous pores. Therefore, the heat resistant composite member according to the first aspect of the present invention is excellent in the ability to repair the damaged portion when the heat resistant and oxidation resistant layer is damaged during use at high temperature.

The heat-resistant composite member according to the second aspect of the present invention has the above-mentioned structure. As a result, by supplying the raw material of the restoration material from the outside, for example, it can be continuously used in a high-temperature reducing atmosphere for a long time.

The heat-resistant composite member according to the second invention is
As a result of using a carbon source that can maintain a gas state at high temperature and can be carbonized by being exposed to high temperature as a raw material of the restorative material, it is possible to prevent clogging in the continuous pores of the porous base material. Therefore, when the heat resistant composite member according to the second aspect of the present invention is damaged during use of the heat resistant layer at high temperatures, the heat resistant composite member has excellent ability to repair the damaged portion.

Further, the first and second heat resistant composite members are
As a result of using the raw material of the restorative material that can maintain the gas state at high temperature, it can be applied to the case where a porous base material having a small porosity and / or a small pore diameter is used.

Further, the first and second heat resistant composite members are
As a result of using the raw material of the restorative material that can maintain the gas state at high temperature, it is not necessary to use a means for forcibly injecting the raw material of the restorative material into the continuous pores of the base material.

The heat-resistant composite member according to the present invention can be continuously used in a high temperature atmosphere for a long time without performing maintenance work such as recoating of a ceramics layer, so that it is particularly limited to the following cases. But not
For example, it can be suitably used as a heat resistant wall for aerospace, high temperature equipment such as a rocket engine nozzle liner, or a furnace wall material of a high temperature furnace.

[Brief description of drawings]

FIG. 1 is a schematic view schematically showing a specific example of a heat resistant composite member according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat resistant composite member 2 Porous base material 2a Front surface of base material 2b Back surface of base material 2h Continuous pores 3 Coating layer 4 Hollow part 5 Jacket 5a Surface of jacket 5 5b Back surface of jacket 5 5ha, 5hb Hole part 8 Crack 9 ceramics

Claims (3)

[Claims] 1. A porous base material having a front surface and a back surface, having heat resistance, and having continuous pores penetrating the front surface and the back surface, and formed so as to cover the surface of the base material. A heat-resistant and oxidation-resistant layer having airtightness, sealing means provided on the back surface side of the base material, and housed in the sealing means, and when the heat-resistant and oxidation-resistant layer is damaged during use at high temperature, The raw material of the restoration material, which flows out from the damaged portion and flows out from the damaged portion and covers the damaged portion, can be kept in a gas state at a high temperature in the seal 21. A heat-resistant composite member including a metal source that can be made into ceramic by being exposed to high temperatures. 2. The heat resistant composite member according to claim 1, wherein the raw material of the restorative material further includes a carbon source capable of maintaining a gas state at a high temperature. 3. A porous base material having a front surface and a back surface, having heat resistance, and having continuous pores penetrating the front surface and the back surface, and formed so as to cover the surface of the base material. A heat-resistant layer having an airtightness, a sealing means provided on the back surface side of the base material, and the continuous pores, which are housed in the sealing means and are damaged when the heat-resistant layer is used at high temperature. The raw material of the restoration material, which flows out from the damaged portion and covers and covers the damaged portion, can hold a gas state at a high temperature in the sealing means and is exposed to the high temperature. A heat-resistant composite member containing a carbon source capable of being carbonized.