CN111875403A

CN111875403A - Connecting material, system, connecting structure and application for connecting silicon carbide materials

Info

Publication number: CN111875403A
Application number: CN202010919097.1A
Authority: CN
Inventors: 周小兵; 史林坤; 余腾; 黄政仁; 黄庆
Original assignee: Hangzhou Bay Research Institute Of Ningbo Institute Of Materials; Ningbo Institute of Material Technology and Engineering of CAS
Current assignee: Hangzhou Bay Research Institute Of Ningbo Institute Of Materials; Ningbo Institute of Material Technology and Engineering of CAS
Priority date: 2020-09-04
Filing date: 2020-09-04
Publication date: 2020-11-03

Abstract

The invention discloses a connecting material, a system, a connecting structure and application for connecting silicon carbide materials. The connecting material comprises Yb and Yb₃Si₂C₂、Yb₃Si₂C₂Any one or a combination of two or more of the coated silicon carbide composite materials. The invention also discloses Yb and Yb₃Si₂C₂Or Yb₃Si₂C₂Use of a coated silicon carbide composite for joining silicon carbide materials. The invention also discloses a connection method of the silicon carbide material, a corresponding system adopted by the connection method and a finally obtained connection structure. The invention utilizes Yb₃Si₂C₂Due to the characteristic of high-temperature decomposition, the generated liquid phase is favorable for the integrated sintering of the silicon carbide of the connecting interface and the silicon carbide of the matrix; the obtained silicon carbide connecting structure has high bending strength and excellent high-temperature resistance, oxidation resistance and corrosion resistanceThe method can be applied to extreme service environments such as aerospace and nuclear energy systems.

Description

Connecting material, system, connecting structure and application for connecting silicon carbide materials

Technical Field

The invention relates to the technical field of connection of silicon carbide ceramics and composite materials thereof, in particular to a method for preparing silicon carbide Yb and ytterbium silicon carbide Yb by utilizing Yb and ytterbium silicon carbide Yb₃Si₂C₂Or the connection material, the connection system and the corresponding connection structure of the ytterbium silicon carbon coated silicon carbide composite material to connect the silicon carbide material, and the application of the connection material and the corresponding connection structure in the connection layer of the silicon carbide and the composite material thereof can be used in the technical field of connection of the silicon carbide and the composite material thereof.

Background

Silicon carbide (SiC) has excellent high-temperature mechanical properties and good oxidation resistance, corrosion resistance, radiation resistance and the like, and Silicon carbide and its composite materials (including Silicon carbide ceramics, Silicon carbide ceramic matrix composite materials, such as Silicon carbide fiber reinforced Silicon carbide composite materials, carbon fiber reinforced Silicon carbide composite materials and the like) are considered as one of the preferred materials for the next-generation nuclear reactor structural materials. Meanwhile, the material has wide application prospect in the aspects of aerospace, hypersonic aircraft thermal protection materials and the like. However, silicon carbide has a high melting point, poor electrical conductivity, near net shape, and difficulty in sintering and processing, and thus, it is generally necessary to employ joining techniques to achieve the fabrication of large-sized, complex-shaped components. On the other hand, silicon carbide has a strong Si-C covalent bond structure and a low surface diffusion coefficient, and a temperature of 2000 ℃ or higher is required to achieve self-bonding of silicon carbide and its composite material.

At present, much work has been done at home and abroad on SiC connection, and the more common connection methods include active metal brazing, diffusion connection, glass ceramic connection, Si — C reaction connection, ceramic precursor connection, transient eutectic connection, MAX connection, and the like. Metal brazing can realize low-temperature connection of silicon carbide, but cannot meet the service requirements of extreme conditions in a nuclear environment. Diffusion bonding typically utilizes a high degree of bonding between the active metal and the silicon carbideThe connection is realized by the warm diffusion reaction, the method is simple and easy to implement, but the brittle phase of the metal silicide is easy to generate, and the amorphous silicon is easy to be formed after neutron irradiation. Glass-ceramic joints, e.g. 54 wt% SiO₂-18.07wt％Al₂O₃-27.93wt％Y₂O₃(SAY)，60wt％SiO₂-30wt％Al₂O₃-10wt％MgO(SAMg)，49.7wt％CaO-50.3wt Al₂O₃Glass ceramics such as (CA) and the like are used as connecting layer materials, are one of effective methods for connecting silicon carbide ceramics in a non-nuclear environment, can realize pressureless connection, and have low connection temperature and good oxidation resistance. However, the application of the glass to the next generation nuclear reactor is limited due to its limited irradiation resistance and low softening point. The Si-C reaction connection is to obtain the SiC connection layer by utilizing the chemical reaction between S and C. The method is theoretically possible to obtain a connecting layer interface without thermal stress, but Si or C can remain, so that the difference between radiation swelling (swelling) and matrix silicon carbide generates stress strain. Otherwise, if the oxygen content of the connecting layer reaches a certain degree, the connecting layer is amorphized after neutron irradiation. The ceramic precursor connection is realized by using a silicon carbide ceramic precursor as a connecting layer and performing polymerization cracking and ceramic treatment on the connecting layer. The method is one of potential connection layer material candidates for the core silicon carbide, and the biggest challenge is that the near stoichiometric silicon carbide is difficult to obtain. Transient eutectic bonding technology was developed by the united states oak ridge laboratory y.katoh group and was first used in the preparation of silicon carbide fiber reinforced silicon carbide composites. The method adopts nano silicon carbide powder and about 10V percent of Al₂O₃–Y₂O₃–SiO₂The sintering aid is used as a connecting layer material to connect silicon carbide at 1800-1900 ℃. The method is one of the effective methods for silicon carbide connection. However, the addition of a large amount of sintering aid is prone to generate defects in extreme environments, and at the same time, the higher connection temperature may cause damage to the fiber structure in the composite material, so that the composite material fails.

In summary, for the connection of silicon carbide, connection layer materials are mostly used for connection at present, however, the problems of mismatch of thermal expansion coefficients, difference of neutron irradiation swelling behaviors, difference of environmental compatibility and the like must exist between the connection layer materials and the matrix silicon carbide, and especially for the application in the fields of nuclear energy and aerospace, the requirements on the thermal property, the mechanics and the like of the connection layer materials and the interface are very high due to the very harsh service environment. Therefore, although researchers in the industry select properties such as high temperature resistance, oxidation resistance, corrosion resistance, etc., such as titanium silicon carbon, titanium aluminum carbon, etc., it is still difficult to meet the actual use requirements.

Disclosure of Invention

The main object of the present invention is to provide a bonding material for bonding silicon carbide materials, which overcomes the disadvantages of the prior art.

It is a further object of the invention to provide the use of said joining material for joining silicon carbide materials.

It is a further object of the present invention to provide a method of joining silicon carbide materials.

It is a further object of the present invention to provide a system for joining silicon carbide materials.

It is a further object of the present invention to provide a multilayer composite film structure for joining silicon carbide materials.

It is still another object of the present invention to provide a connection structure between silicon carbide materials.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps:

the embodiment of the invention provides a connecting material for connecting silicon carbide materials, and the connecting material comprises Yb and Yb₃Si₂C₂Or Yb₃Si₂C₂Any one or a combination of two or more of the coated silicon carbide composite materials.

The embodiment of the invention also provides Yb and Yb₃Si₂C₂Or Yb₃Si₂C₂Use of a coated silicon carbide composite for joining silicon carbide materials.

Further, the use comprises: yb and Yb are arranged at the connecting interface of the silicon carbide materials to be connected₃Si₂C₂Or Yb₃Si₂C₂Coated silicon carbideAnd (3) combining the materials, and heating to 700-1700 ℃ to combine the silicon carbide materials to be connected into a whole.

The embodiment of the invention also provides a method for connecting the silicon carbide materials, which comprises the following steps: yb, Yb are arranged at the connecting interface of two silicon carbide materials to be connected₃Si₂C₂Or Yb₃Si₂C₂And coating the silicon carbide composite material, and heating to 700-1700 ℃ to combine the silicon carbide materials to be connected into a whole.

The embodiment of the invention also provides a silicon carbide connecting structure prepared by the method.

Embodiments of the present invention further provide a system for connecting silicon carbide materials, which includes:

a joining material disposed at a splice interface of two silicon carbide members, the joining material comprising a Yb film, Yb₃Si₂C₂Film or Yb₃Si₂C₂Coating a silicon carbide composite material film; and

and the heating device is at least used for heating the splicing interface of the two silicon carbide components to connect the two silicon carbide components into a whole, and the heating temperature is 700-1700 ℃.

The embodiment of the invention also provides a multilayer composite film structure for connecting the silicon carbide materials, wherein the multilayer composite film structure is of a laminated structure along a set direction;

wherein the multilayer composite film structure comprises two Yb films, and a silicon carbide layer and a Yb layer are arranged between the two Yb films₃Si₂C₂Film, Yb₃Si₂C₂Any one or combination of more of the coated silicon carbide composite films;

alternatively, the multilayer composite film structure comprises two Yb₃Si₂C₂Film, and the two Yb₃Si₂C₂Between the films, Yb film, silicon carbide layer and Yb are arranged₃Si₂C₂Any one or combination of more of the coated silicon carbide composite films;

orThe multilayer composite film structure comprises at least one Yb₃Si₂C₂Coated with a silicon carbide composite film of Yb₃Si₂C₂The silicon carbide-coated composite material film comprises a silicon carbide layer and Yb coated on both side surfaces of the silicon carbide layer₃Si₂C₂And (4) coating.

The embodiment of the invention also provides a connection structure between the silicon carbide materials, which consists of the silicon carbide materials to be connected and a connection material, wherein the connection material is arranged at the connection interface of the silicon carbide materials to be connected, the silicon carbide materials to be connected are connected into a whole through the connection material in a heating connection mode of an external heat source, and the connection material is the multilayer composite film structure.

Compared with the prior art, the invention has the beneficial effects that:

1) the invention can obtain ytterbium silicon carbon (Yb) in situ at the connecting interface by utilizing the interface reaction between Yb and the matrix silicon carbide₃Si₂C₂) Phase of Yb₃Si₂C₂The silicon carbide and the liquid phase can be separated out in situ by the characteristic of decomposition at high temperature, and the liquid phase can be further diffused into a crystal boundary and/or a pore of the silicon carbide at the connecting interface as a sintering aid, so that the connection and densification of the silicon carbide at the interface are promoted, and seamless connection can be realized;

2) the seamless connection is realized, the microstructure and the macroscopic property of the connecting area of the obtained silicon carbide connecting structure and the matrix silicon carbide are similar, the bending strength is high, the high-temperature resistance, the oxidation resistance and the corrosion resistance are excellent, the failure caused by the thermal mismatch of the connecting layer material and the matrix silicon carbide, the difference of the environmental compatibility and the like in the prior art can be effectively solved, and the silicon carbide connecting structure can be applied to extreme service environments such as aerospace and nuclear energy systems.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIGS. 1A-1D are schematic views of a structure to be bonded with a silicon carbide material before bonding with a bonding material, and a bonded structure of silicon carbide after bonding, according to an exemplary embodiment of the invention;

FIG. 1E is a pictorial representation of a bonded structure of silicon carbide after bonding in an exemplary embodiment of the invention;

FIG. 2 is a schematic diagram of a system for joining silicon carbide materials in accordance with an exemplary embodiment of the present invention;

FIGS. 3A-3C are schematic structural diagrams of a multilayer composite membrane structure according to an exemplary embodiment of the present invention;

FIG. 4 shows Yb of 100nm and Yb of 10 μmYb in example 1 of the present invention₃Si₂C₂Scanning electron microscope photos of interface backscattering of the film and 100nm Yb connected silicon carbide ceramic connection structure;

FIG. 5 shows Yb of 500nm and 1. mu. mYb in example 2 of the present invention₃Si₂C₂Scanning electron microscope photos of interface back scattering of the silicon carbide ceramic connection structure after the film and the 500nm Yb are connected;

FIG. 6 is an SEM image of the interface of the bonded structure of the SiC ceramic material after the bonding of the 1 μm Yb-coated SiC composite material in example 3 of the present invention;

FIG. 7 is an SEM image of the interface of a 100nm Yb bonded SiC ceramic bonded structure in example 4 of the present invention;

FIG. 8 is an SEM photograph of the interface of the SiC bonded structure obtained in comparative example 1 of the present invention.

Description of the drawings: 1-Yb film, 2-Yb₃Si₂C₂The film comprises a film, a 3-SiC layer, a 100-silicon carbide substrate, a 200-multilayer composite film structure, a 300-graphite felt, a 400-graphite sleeve, a 500-graphite pressure head, a 600-infrared temperature measuring device, a 700-heating device, an 800-atmosphere control device, a 900-vacuumizing device and P-axial pressure.

Detailed Description

Aiming at the existing silicon carbide and the compound thereofThe defects of the composite material connection technology are that the inventor finds that the Yb is utilized in the process of long-term research and massive practice₃Si₂C₂Based on the unexpected finding that the seamless connection of silicon carbide materials can be realized with high efficiency due to the characteristic of pyrolysis, the inventor of the present invention has proposed the technical scheme of the present invention, and further explanation of the technical scheme, the implementation process and the principle thereof will be provided as follows.

In one aspect, the present invention relates to a bonding material for bonding silicon carbide materials, the bonding material including Yb, and Yb₃Si₂C₂Or ytterbium silicon carbon Yb₃Si₂C₂A silicon carbide-coated composite material, or the like.

Further, the ytterbium silicon carbon Yb₃Si₂C₂The silicon carbide-coated composite material comprises ytterbium silicon carbide and silicon carbide particles, wherein the surfaces of the silicon carbide particles are uniformly coated with the ytterbium silicon carbide.

Further, the ytterbium silicon carbon Yb₃Si₂C₂The content of ytterbium silicon carbon in the coated silicon carbide composite material is 1-90 wt%.

Further, the ytterbium silicon carbon Yb₃Si₂C₂Yb is prepared from Yb silicon carbon by casting or presintering₃Si₂C₂。

As one aspect of the invention, the Yb and Yb series are related to the Yb and Yb silicon carbide₃Si₂C₂Or ytterbium silicon carbon Yb₃Si₂C₂Use of a coated silicon carbide composite for joining silicon carbide materials.

In some embodiments, the use comprises: yb, ytterbium silicon carbon Yb are arranged at the connecting interface of the silicon carbide materials to be connected₃Si₂C₂Or ytterbium silicon carbon Yb₃Si₂C₂And coating the silicon carbide composite material, and heating to 700-1700 ℃ to combine the silicon carbide materials to be connected into a whole, thereby realizing seamless connection.

In some more preferred embodiments, the use comprises: setting Yb film and Yb silicon carbon Yb at the connection interface of two silicon carbide materials to be connected₃Si₂C₂Or ytterbium silicon carbon Yb₃Si₂C₂And coating the silicon carbide composite material.

Further, the Yb film has a thickness of 1 μm or less, preferably 50 to 500 nm. The inventor of the invention discovers through a great deal of experiments that when the Yb film is selected as the connecting material and the thickness of the film is controlled to be less than 1 mu m, the connected silicon carbide ceramic interface can realize seamless connection, the interface phase is mainly silicon carbide, the silicon carbide ceramic interface has good high-temperature resistance and oxidation resistance, and the obtained silicon carbide connecting interface has high bending strength.

Further, the ytterbium silicon carbon Yb₃Si₂C₂Or the thickness of the ytterbium silicon carbon coated silicon carbide composite material is less than 1mm, and preferably 0.5-500 mu m.

In some embodiments, the connecting material comprises ytterbium silicon carbon Yb₃Si₂C₂Yb, the ytterbium silicon carbon Yb₃Si₂C₂Can be decomposed to obtain silicon carbide and liquid phase.

In some embodiments of the invention, ytterbium silicon carbon Yb is utilized₃Si₂C₂Phase transformation at high temperature and Yb₃Si₂C₂The silicon carbide and the liquid phase can be obtained by decomposition at a certain temperature, and the formed liquid phase can be used as a sintering aid and can be easily diffused to a grain boundary and/or a pore of the silicon carbide at the connecting interface, so that the diffusion, connection and densification of the silicon carbide at the interface are promoted, and seamless connection can be realized. Meanwhile, along with the volatilization and extrusion of the liquid phase at high temperature, SiC can be precipitated in situ from the liquid phase in the cooling process, and the seamless connection is expected to be realized. Thus, after high-temperature bonding, the bonding zone material is silicon carbide, with the exception of a small residual Yb oxideThe obtained connecting structure has good high-temperature resistance, oxidation resistance, corrosion resistance and other properties.

In some embodiments, the silicon carbide material includes, but is not limited to, pure silicon carbide ceramic materials, silicon carbide ceramic matrix composites, and the like.

Further, the silicon carbide ceramic matrix composite includes any one or a combination of two or more of silicon carbide fiber-reinforced silicon carbide composite, carbon fiber-reinforced silicon carbide composite, silicon carbide whisker-reinforced titanium silicon carbon composite, silicon carbide fiber-reinforced titanium silicon carbon material, silicon carbide fiber-reinforced titanium carbide material, and the like, but is not limited thereto.

Layered rare earth carbo-silicide (Yb) of the invention₃Si₂C₂Yb) coating can be prepared on the surface of curved surface or even complex geometric shape silicon carbide and its composite material.

As another aspect of the present invention, it further relates to a method for bonding silicon carbide materials, as shown in fig. 1A to 1D, including: yb, ytterbium silicon carbon Yb are arranged at the connecting interface of two silicon carbide materials to be connected₃Si₂C₂Or ytterbium silicon carbon Yb₃Si₂C₂And coating the silicon carbide composite material, and heating to 700-1700 ℃ to combine the silicon carbide materials to be connected into a whole, thereby realizing seamless connection.

In some embodiments, the connection method comprises: setting Yb film and Yb silicon carbon Yb at the connection interface of silicon carbide materials to be connected₃Si₂C₂Or ytterbium silicon carbon Yb₃Si₂C₂And coating the silicon carbide composite material.

Still further, the connection method comprises: coating Yb-Si-C-Yb on the connecting interface of the silicon carbide materials to be connected₃Si₂C₂A rare earth carbo-silicide coating, preferably a rare earth carbo-silicide film, is formed.

In some embodiments of the invention, ytterbium silicon carbon Yb is utilized₃Si₂C₂Phase transformation at high temperature and Yb₃Si₂C₂The silicon carbide and the liquid phase can be obtained by decomposition at a certain temperature, and the formed liquid phase can be used as a sintering aid and can be easily diffused to a grain boundary and/or a pore of the silicon carbide at the connecting interface, so that the diffusion, connection and densification of the silicon carbide at the interface are promoted, and seamless connection can be realized. Meanwhile, along with the volatilization and extrusion of the liquid phase at high temperature, SiC can be precipitated in situ from the liquid phase in the cooling process, and the seamless connection is expected to be realized. Therefore, after high-temperature connection, the material of the connection region is silicon carbide except a small amount of residual Yb oxide, and the obtained connection structure has good high-temperature resistance, oxidation resistance, corrosion resistance and the like.

The invention can obtain ytterbium silicon carbon Yb at the interface by utilizing the interface reaction between the lanthanide rare earth element Yb and the matrix silicon carbide₃Si₂C₂Phase, Yb, using ytterbium silicon carbon₃Si₂C₂Phase transformation at high temperature and Yb₃Si₂C₂The silicon carbide and the liquid phase can be obtained by decomposition at a certain temperature, and the formed liquid phase can be used as a sintering aid and can be easily diffused to a grain boundary and/or a pore of the silicon carbide at the connecting interface, so that the diffusion, connection and densification of the silicon carbide at the interface are promoted, and seamless connection can be realized. Meanwhile, along with the volatilization and extrusion of the liquid phase at high temperature, SiC can be precipitated in situ from the liquid phase in the cooling process, and the seamless connection is expected to be realized. Therefore, after high-temperature connection, the material of the connection region is silicon carbide except a small amount of residual Yb oxide, and the obtained connection structure has good high-temperature resistance, oxidation resistance, corrosion resistance and the like.

Further, the preparation method of the connection material of the present invention is not limited, and the lanthanide rare earth Yb film can be obtained by depositing the lanthanide rare earth Yb film on the surface of the substrate by a Physical Vapor Deposition (PVD) method, and finally removing the substrate. Or, carrying out physical vapor deposition on the surface of the silicon carbide ceramic material to be connected to form a lanthanide rare earth element Yb film; yb is silicon carbon₃Si₂C₂The material can be obtained by a solid-phase reaction method and is made into a casting film or a pre-sintered ceramic sheet; the ytterbium silicon carbon-coated silicon carbide composite material can be obtained by a solid-phase ball milling or high-temperature molten salt method and comprises a mixture of ytterbium silicon carbon and silicon carbide, wherein the mass percentage of ytterbium silicon carbon is 1-90 wt%; the structure is characterized in that ytterbium silicon carbon is preferably uniformly coated on the surface of the silicon carbide particle.

Accordingly, another aspect of an embodiment of the present invention also provides a silicon carbide connection structure made by the foregoing method.

In some preferred embodiments, the silicon carbide connection structure comprises a silicon carbide substrate region and a connection region integrally bonded to the silicon carbide substrate region, wherein the connection region is distributed between the two silicon carbide substrate regions, and the connection region is mainly composed of silicon carbide and further contains a small amount of Yb diffusion body, and the Yb diffusion body can be distributed in grain boundaries and/or pores of the silicon carbide structure of the connection region.

Further, the connection region in the silicon carbide connection structure may disappear and do not exist, or the connection portion is mainly composed of a silicon carbide phase.

Further, the connecting region of the silicon carbide connecting structure has a strength greater than that of the base region.

Furthermore, the bending strength of the silicon carbide connecting structure is 100-600 MPa, the size of the silicon carbide connecting structure depends on the bending strength of silicon carbide or a silicon carbide ceramic matrix composite material, and the high-temperature resistance, oxidation resistance and corrosion resistance are excellent.

In another aspect of the embodiments of the present invention, an application of the foregoing silicon carbide connection structure in the field of preparation of aerospace materials or nuclear energy systems is also provided.

Furthermore, the obtained silicon carbide connecting structure has high bending strength and excellent high-temperature resistance, oxidation resistance and corrosion resistance, and can be applied to extreme service environments such as aerospace and nuclear energy systems.

Another aspect of an embodiment of the present invention also provides a system for joining silicon carbide materials, comprising:

Further, the Yb film has a thickness of 1 μm or less, preferably 50 to 500 nm.

Further, the ytterbium silicon carbon Yb₃Si₂C₂Film or ytterbium silicon carbon Yb₃Si₂C₂The thickness of the coated silicon carbide composite material film is less than 1mm, and preferably 0.5 to 500 μm.

Further, the system also includes a pressurization device for providing a force that presses the two silicon carbide members against each other at the splice interface.

Further, the heating device may be a hot pressing device, but is not limited thereto, and for example, the heating device may also be an electric field auxiliary heating device, a microwave field auxiliary heating device, a discharge plasma sintering furnace, or the like.

Further, the system also comprises an atmosphere control device, a vacuum pumping device and the like.

Further, the system also comprises an infrared temperature measuring device.

In some more specific embodiments, referring to fig. 2, a system for bonding silicon carbide materials according to the present invention specifically includes: the silicon carbide component splicing device comprises a connecting material arranged at a splicing interface of two silicon carbide components (specifically a silicon carbide substrate 100), and a heating device 700 at least used for heating the splicing interface of the two silicon carbide components to connect the two silicon carbide components into a whole, wherein the heating temperature is 700-1700 ℃.

Wherein the connecting material comprises Yb film and Yb₃Si₂C₂Film or Yb₃Si₂C₂The silicon carbide composite film is coated, i.e., may be a multilayer composite film structure 200.

The system further comprises a heat insulation structure which is arranged on the outer sides of the two silicon carbide components, specifically, the heat insulation structure can be a graphite felt 300, a graphite sleeve 400 and the like, the surface of the silicon carbide substrate 100 is further provided with an infrared temperature measuring device 600, and the system further comprises a pressurizing device, namely a graphite pressure head 500, which is used for providing axial pressure P for enabling the two silicon carbide substrates 100 to be mutually extruded at the splicing interface.

Wherein the system further comprises an atmosphere control device 800 and a vacuum device 900.

As another aspect of the technical solution of the present invention, it relates to a multilayer composite film structure for bonding silicon carbide materials, the multilayer composite film structure having a laminated structure in a set direction;

alternatively, the multilayer composite film structure comprises at least one Yb₃Si₂C₂Coated with a silicon carbide composite film of Yb₃Si₂C₂The silicon carbide-coated composite material film comprises a silicon carbide layer and Yb coated on both side surfaces of the silicon carbide layer₃Si₂C₂And (4) coating.

In some preferred embodiments, the multilayer composite film structure includes two Yb films with at least two silicon carbide layers and at least two Yb films disposed therebetween₃Si₂C₂Film of silicon carbide layer and Yb₃Si₂C₂The membranes are alternately arranged along a set direction;

alternatively, the multilayer composite film structure comprises two Yb₃Si₂C₂Film, and the two Yb₃Si₂C₂At least two Yb films and at least one silicon carbide layer are arranged between the films, wherein one silicon carbide layer is distributed between the two Yb films.

Further, the thickness of the single layer Yb film is 1 μm or less, preferably 50 to 500nm, in the stacking direction of the multilayer composite film structure.

Further, a single layer of ytterbium silicon carbon Yb is arranged along the lamination direction of the multilayer composite film structure₃Si₂C₂Film orYtterbium silicon carbon Yb₃Si₂C₂The thickness of the coated silicon carbide composite material film is less than 1mm, and preferably 0.5 to 500 μm.

In some embodiments, referring to FIG. 3A, the multi-layer composite film structure comprises a Yb film 1 and a Yb silicon carbon Yb sequentially stacked₃Si₂C₂Film 2 and Yb film 1.

In other embodiments, referring to FIG. 3B, the multi-layer composite film structure comprises Yb and Yb sequentially stacked₃Si₂C₂Film 2, Yb film 1, SiC layer 3, Yb film 1, and Yb silicon carbide Yb₃Si₂C₂And (2) a membrane.

In other embodiments, referring to FIG. 3C, the multi-layer composite film structure comprises a Yb film 1, a SiC layer 3, and Yb₃Si₂C₂Film 2, SiC layer 3, Yb of ytterbium silicon carbon₃Si₂C₂Film 2 and Yb film 1.

In another aspect of the present invention, a connection structure between silicon carbide materials is provided, which includes a silicon carbide material to be connected and a connection material, the connection material is disposed at a connection interface of the silicon carbide materials to be connected, and the silicon carbide materials to be connected are connected integrally by the connection material in a heating connection manner using an external heat source, and the connection material is the aforementioned multilayer composite film structure.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention are explained in further detail below with reference to the accompanying drawings and several preferred embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

In this example, as shown in FIG. 1B, Yb of 100nm and 10 μmYb are shown₃Si₂C₂Connection of film, 100nm Yb to silicon carbide ceramicThe structure is schematic. The material to be connected is two pieces of silicon carbide with phi of 20 multiplied by 20mm, the material of the connecting layer is 100nm Yb and 10 mu mYb₃Si₂C₂And (3) heating the connection interface of the film and 100nm Yb by the aid of an electric field to enable the connection interface to reach 1300 ℃, so that SiC materials to be connected are connected together. The method comprises the following specific steps:

(1) polishing the surface of the silicon carbide to be connected to 1 micron by using diamond polishing solution, and removing defects and impurities on the surface;

(2) plating 100nm Yb film on two silicon carbide surfaces to be connected by physical vapor deposition method, and then plating 10 mu mYb₃Si₂C₂The film is sandwiched between two pieces of silicon carbide plated with a 100nm Yb film; and then putting the sample into a graphite mold, then putting the graphite mold into a discharge plasma sintering furnace, electrifying, heating to the furnace temperature of 1700 ℃ at the heating rate of 50 ℃/min, preserving the temperature for 10min, applying the pressure of 30MPa to the connection sample in the heating process, and then cooling to the room temperature at the speed of 100 ℃/min to obtain the silicon carbide connection structure, wherein a material object diagram of the silicon carbide connection structure can be shown in figure 1E.

The microscopic morphology of the interface of the silicon carbide connection structure obtained in the embodiment is observed by using a scanning electron microscope, and a back scattering scanning electron microscope photo is shown in fig. 4, which shows that the connection interface has no obvious cracks, the connection layer is compact, and the strength is high.

And cutting and polishing the obtained silicon carbide connecting structure, processing the silicon carbide connecting structure into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, testing the four-point bending strength of the sample strip to be about 200Mpa by adopting a four-point bending method, and breaking the sample strip on the matrix silicon carbide, wherein the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 2

In this example, as shown in FIG. 1B, Yb of 500nm and 1 μmYb are shown₃Si₂C₂The film and 500nm Yb are connected with the silicon carbide ceramic. The material to be connected is two pieces of silicon carbide with phi of 20 multiplied by 20mm, the material of the connecting layer is 500nm Yb and 1 mu mYb₃Si₂C₂The film and the 500nm Yb multilayer composite material are connected by electric field auxiliary heating to make the connection interface reach 1500 ℃, thereby connecting the SiC materials to be connectedAre connected together. The method comprises the following specific steps:

(2) plating a 500nm Yb film on the surfaces of two silicon carbide wafers to be connected by physical vapor deposition, and then plating 1 mu mYb₃Si₂C₂The film is sandwiched between two pieces of silicon carbide plated with a 500nm Yb film; and then putting the sample into a graphite mold, then putting the graphite mold into a discharge plasma sintering furnace, electrifying, heating to the furnace temperature of 1700 ℃ at the heating rate of 100 ℃/min, preserving the temperature for 20min, applying the pressure of 35MPa to the connection sample in the heating process, and then cooling to the room temperature at the speed of 50 ℃/min to obtain the silicon carbide connection structure.

The microscopic morphology of the interface of the silicon carbide connection structure obtained in this example was observed with a scanning electron microscope, and a back-scattered scanning electron micrograph shown in FIG. 5 shows that the connection interface has no significant cracks and consists of Yb at high temperatures₃Si₂C₂And the silicon carbide is further sintered and integrated with the matrix silicon carbide under the action of the liquid phase, so that seamless connection is realized, almost no connecting layer is left, and the strength is high.

And cutting and polishing the obtained silicon carbide connecting structure, processing the silicon carbide connecting structure into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, testing the four-point bending strength of the sample strip by adopting a four-point bending method to be about 267Mpa, and breaking the sample strip on the matrix silicon carbide, wherein the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 3

In this embodiment, as shown in fig. 1C, a schematic view of a connection structure of a 1 μm Yb-coated silicon carbide composite material to a silicon carbide ceramic is shown. The materials to be connected are two pieces of silicon carbide with phi of 20 multiplied by 20mm, the materials of the connecting layer are 1 mu m Yb coated silicon carbide composite materials, and the connecting interface is heated by the aid of an electric field to reach 1600 ℃, so that the SiC materials to be connected are connected together. The method comprises the following specific steps:

(2) preparing a 1-micron Yb-coated silicon carbide composite material by a molten salt method, preparing a casting film, clamping the 1-micron Yb-coated silicon carbide composite material casting film between two pieces of silicon carbide, putting a sample into a graphite mold, then putting the graphite mold into a discharge plasma sintering furnace, electrifying, heating to the furnace temperature of 1600 ℃ at the heating rate of 50 ℃/min, preserving the temperature for 10min, applying 50MPa pressure to a connection sample in the heating process, and then cooling to the room temperature at the speed of 50 ℃/min to obtain the silicon carbide connection structure.

The microscopic morphology of the interface of the silicon carbide connection structure obtained in this example was observed with a scanning electron microscope, and a scanning electron micrograph is shown in fig. 6, which shows that the connection interface has no obvious connection layer and has high connection strength.

And cutting and polishing the obtained silicon carbide connecting structure, processing the silicon carbide connecting structure into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, testing the four-point bending strength of the sample strip by adopting a four-point bending method to be about 249Mpa, and testing the sample strip to be broken on the matrix silicon carbide, wherein the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 4

In this embodiment, as shown in fig. 1A, a schematic diagram of a connection structure of 100nm Yb-connected silicon carbide ceramics is shown. The materials to be connected are two pieces of silicon carbide with phi of 20 multiplied by 20mm, the materials of the connecting layer are 100nm Yb films, and the connecting interface is heated by the aid of an electric field to reach 1300 ℃, so that the SiC materials to be connected are connected together. The method comprises the following specific steps:

(1) polishing the surface of the silicon carbide to be connected to 0.1 mu m by using diamond polishing solution, and removing defects and impurities on the surface;

(2) plating a 100nmYb film on the surface of one piece of silicon carbide to be connected by a PVD method, and then butting the other piece of silicon carbide with the surface of the other piece of silicon carbide; and then putting the sample into a graphite mold, then putting the graphite mold into a discharge plasma sintering furnace, electrifying, heating to the furnace temperature of 1300 ℃ at the heating rate of 10 ℃/min, preserving the temperature for 10min, applying the pressure of 50MPa to the connection sample in the heating process, and then cooling to the room temperature at the speed of 50 ℃/min to obtain the silicon carbide connection structure.

The microscopic morphology of the interface of the silicon carbide connection structure obtained in this example was observed with a scanning electron microscope, and a scanning electron micrograph shown in fig. 7 shows that the connection interface had no significant cracks, the connection layer had substantially disappeared, and the strength was high.

And cutting and polishing the obtained silicon carbide connecting structure, processing the silicon carbide connecting structure into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, testing the four-point bending strength of the sample strip to be about 220Mpa by adopting a four-point bending method, and breaking the sample strip on the matrix silicon carbide, wherein the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 5

In the embodiment, the materials to be connected are two pieces of silicon carbide with the phi of 20 multiplied by 20mm, the material of the connecting layer is a 50nm Yb film, and the connecting interface is heated by the aid of a microwave field to reach 800 ℃, so that the SiC materials to be connected are connected together. The method comprises the following specific steps:

(2) plating a 50nmYb film on the surface of one piece of silicon carbide to be connected by a PVD method, and then butting the other piece of silicon carbide with the surface of the other piece of silicon carbide; and then putting the sample into a microwave field auxiliary heating furnace, heating to 800 ℃ at the heating rate of 5 ℃/min, preserving the temperature for 120min, and then cooling to room temperature at the speed of 5 ℃/min to obtain the silicon carbide connecting structure.

The microscopic morphology of the interface of the silicon carbide connecting structure obtained in the embodiment is observed by using a scanning electron microscope, and a back scattering scanning electron microscope photo is similar to that shown in fig. 4, so that the connecting interface has no obvious cracks and high strength.

And cutting and polishing the obtained silicon carbide connecting structure, processing the silicon carbide connecting structure into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, testing the four-point bending strength of the sample strip to be about 190Mpa by adopting a four-point bending method, and breaking the sample strip on the matrix silicon carbide, wherein the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 6

In the embodiment, the materials to be connected are two pieces of silicon carbide with the phi of 20 multiplied by 20mm, the material of the connecting layer is a 1-micron Yb film, and the connecting interface is connected by hot pressing to reach 1400 ℃, so that the SiC materials to be connected are connected together. The method comprises the following specific steps:

(2) plating a 1 mu mYb film on the surface of one piece of silicon carbide to be connected by a PVD method, and butting the other piece of silicon carbide with the surface of the other piece of silicon carbide; and then putting the sample into a microwave field auxiliary heating furnace, heating to the furnace temperature of 1400 ℃ at the heating rate of 5 ℃/min, preserving the temperature for 100min, and then cooling to the room temperature at the speed of 5 ℃/min to obtain the silicon carbide connecting structure.

The microscopic morphology of the interface of the silicon carbide connecting structure obtained in the embodiment is observed by using a scanning electron microscope, and a back scattering scanning electron microscope photo is similar to that shown in fig. 6, so that the connecting interface has no obvious cracks and high strength.

Example 7

In this embodiment, the materials to be connected are two pieces of silicon carbide fiber reinforced silicon carbide composite material with phi 20 × 20mm, and the material of the connecting layer is 1 mu mYb₃Si₂C₂And connecting the silicon carbide fiber reinforced silicon carbide composite materials to be connected together by hot-pressing the connecting interface to make the connecting interface reach 1200 ℃. The method comprises the following specific steps:

(1) polishing the surface of the silicon carbide fiber reinforced silicon carbide composite material to be connected to 1 micron by using diamond polishing solution, and removing defects and impurities on the surface;

(2) plating 1 mu mYb on the surface of the silicon carbide fiber reinforced silicon carbide composite material to be connected by a thermal spraying method₃Si₂C₂Then, another piece of silicon carbide fiber reinforced silicon carbide composite material is butted with the silicon carbide fiber reinforced silicon carbide composite material; the sample was then placed in a hot press at 5 deg.C/miAnd n, raising the temperature to 1200 ℃ at the temperature raising rate, preserving the temperature for 120min, and then lowering the temperature to room temperature at the rate of 5 ℃/min to obtain the silicon carbide fiber reinforced silicon carbide composite material connecting structure.

The microscopic morphology of the interface of the silicon carbide fiber reinforced silicon carbide composite material obtained in the embodiment is observed by using a scanning electron microscope, and a back scattering scanning electron micrograph is similar to that in FIG. 5, which shows that the connecting interface has no obvious cracks and high strength.

The obtained silicon carbide fiber reinforced silicon carbide composite material connecting structure is cut and polished to be processed into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, the four-point bending strength of the sample strip is tested to be about 360Mpa by adopting a four-point bending method, and the sample strip is broken on the matrix silicon carbide fiber reinforced silicon carbide composite material, so that the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide fiber reinforced silicon carbide composite material.

Example 8

In this embodiment, the material to be connected is two carbon fiber reinforced silicon carbide composite materials with phi 20 × 20mm, and the material of the connecting layer is 100 μm Yb₃Si₂C₂And the connecting interface reaches 1500 ℃ through a pressureless connecting interface, so that the carbon fiber reinforced silicon carbide composite materials to be connected are connected together. The method comprises the following specific steps:

(1) polishing the surface of the carbon fiber reinforced silicon carbide composite material to be connected to 1 micron by using diamond polishing solution, and removing defects and impurities on the surface;

(2) yb of₃Si₂C₂Preparing a casting film with the thickness of 100 microns, placing the casting film on the surface of the carbon fiber reinforced silicon carbide composite material to be connected, and butting the other carbon fiber reinforced silicon carbide composite material with the casting film; and then putting the sample into a vacuum furnace, heating to the furnace temperature of 1500 ℃ at the heating rate of 5 ℃/min, preserving the temperature for 200min, and then cooling to the room temperature at the heating rate of 5 ℃/min to obtain the carbon fiber reinforced silicon carbide composite material connecting structure.

The microscopic morphology of the interface of the carbon fiber reinforced silicon carbide composite material obtained in the embodiment is observed by using a scanning electron microscope, and a back scattering scanning electron microscope photo is similar to that in FIG. 6, and shows that the connecting interface has no obvious cracks and high strength.

The obtained silicon carbide fiber reinforced silicon carbide composite material connecting structure is cut and polished to be processed into a 4X 3X 40mm sample strip, the four-point bending strength of the sample strip is tested to be about 136Mpa by adopting a four-point bending method, and the sample strip is broken on the matrix silicon carbide, which shows that the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 9

In this embodiment, the materials to be connected are two silicon carbide fiber reinforced silicon carbide composite materials with phi of 20 × 20mm, and the material of the connecting layer is 1mm Yb₃Si₂C₂And connecting the silicon carbide fiber reinforced silicon carbide composite materials to be connected together by hot-pressing the connecting interface to reach 1700 ℃. The method comprises the following specific steps:

(2) yb of₃Si₂C₂Preparing a casting film with the thickness of 1mm, placing the casting film on the surface of the silicon carbide fiber reinforced silicon carbide composite material to be connected, and then butting the other silicon carbide fiber reinforced silicon carbide composite material with the other silicon carbide fiber reinforced silicon carbide composite material; and then putting the sample into a hot pressing furnace, heating to the furnace temperature of 1700 ℃ at the heating rate of 5 ℃/min, preserving the temperature for 360min, and then cooling to the room temperature at the speed of 5 ℃/min to obtain the silicon carbide fiber reinforced silicon carbide composite material connecting structure.

The microscopic morphology of the interface of the silicon carbide fiber reinforced silicon carbide composite material obtained in the embodiment is observed by using a scanning electron microscope, and a back scattering scanning electron micrograph is similar to that in FIG. 6, which shows that the connecting interface has no obvious cracks and high strength.

The obtained silicon carbide fiber reinforced silicon carbide composite material connecting structure is cut and polished to be processed into a 4X 3X 40mm sample strip, the four-point bending strength of the sample strip is tested to be about 283Mpa by adopting a four-point bending method, and the sample strip is broken on the matrix silicon carbide, which shows that the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 10

In the embodiment, the materials to be connected are two silicon carbide fiber reinforced silicon carbide composite materials with phi 20 x 20mm, the material of the connecting layer is 100 mu mYb coated silicon carbide composite material, and the connecting interface is assisted by an electric field to reach 1400 ℃, so that the silicon carbide fiber reinforced silicon carbide composite materials to be connected are connected together. The method comprises the following specific steps:

(2) preparing a Yb-coated silicon carbide composite material into a casting film with the thickness of 100 microns, placing the casting film on the surface of a silicon carbide fiber reinforced silicon carbide composite material to be connected, and then butting another silicon carbide fiber reinforced silicon carbide composite material with the casting film; and then putting the sample into a discharge plasma sintering furnace, electrifying, applying 10MPa axial pressure, heating to the furnace temperature of 1400 ℃ at the heating rate of 100 ℃/min, preserving the temperature for 30min, and then cooling to room temperature at the speed of 50 ℃/min to obtain the silicon carbide fiber reinforced silicon carbide composite material connecting structure.

The obtained silicon carbide fiber reinforced silicon carbide composite material connecting structure is cut and polished to be processed into a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, the four-point bending strength of the sample strip is about 288Mpa by adopting a four-point bending method, and the sample strip is broken on the matrix silicon carbide, which shows that the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 11

In this embodiment, the materials to be connected are two silicon carbide fiber reinforced silicon carbide composite materials with a phi of 20 × 20mm, the material of the connecting layer is a Yb-coated silicon carbide composite material with a thickness of 10 μm, and the connecting interface is assisted by an electric field to reach 1700 ℃, so that the silicon carbide fiber reinforced silicon carbide composite materials to be connected are connected together. The method comprises the following specific steps:

(2) preparing a Yb-coated silicon carbide composite material into a casting film with the thickness of 10 microns, placing the casting film on the surface of a silicon carbide fiber reinforced silicon carbide composite material to be connected, and then butting another silicon carbide fiber reinforced silicon carbide composite material with the casting film; and then putting the sample into a discharge plasma sintering furnace, electrifying, applying 30MPa of axial pressure, heating to the furnace temperature of 1700 ℃ at the heating rate of 50 ℃/min, preserving the temperature for 30min, and then cooling to the room temperature at the speed of 50 ℃/min to obtain the silicon carbide fiber reinforced silicon carbide composite material connecting structure.

The obtained silicon carbide fiber reinforced silicon carbide composite material connecting structure is cut and polished to be processed into a 4X 3X 40mm sample strip, the four-point bending strength of the sample strip is tested to be about 290Mpa by adopting a four-point bending method, and the sample strip is broken on the matrix silicon carbide, which shows that the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Example 12

In this embodiment, the materials to be connected are two silicon carbide fiber reinforced silicon carbide composite materials with a phi of 20 × 20mm, the material of the connecting layer is a 200nm Yb film, and the electric field is used to assist the connecting interface, so that the connecting interface reaches 1000 ℃, thereby connecting the silicon carbide fiber reinforced silicon carbide composite materials to be connected together. The method comprises the following specific steps:

(1) polishing the surface of the silicon carbide fiber reinforced silicon carbide composite material to be connected to 0.1 mu m by using diamond polishing solution, and removing defects and impurities on the surface;

(2) preparing a 200nm Yb film on the surface of the silicon carbide fiber reinforced silicon carbide composite material by a spraying method, and then butting the other silicon carbide fiber reinforced silicon carbide composite material with the other silicon carbide fiber reinforced silicon carbide composite material; and then putting the sample into a discharge plasma sintering furnace, electrifying, applying 50MPa axial pressure, heating to the furnace temperature of 1000 ℃ at the heating rate of 30 ℃/min, preserving the temperature for 10min, and then cooling to room temperature at the speed of 30 ℃/min to obtain the silicon carbide fiber reinforced silicon carbide composite material connecting structure.

The obtained silicon carbide fiber reinforced silicon carbide composite material connecting structure is cut and polished to be processed into a 4X 3X 40mm sample strip, the four-point bending strength of the sample strip is tested to be about 260Mpa by adopting a four-point bending method, and the sample strip is broken on the matrix silicon carbide, which shows that the strength of a connecting layer and an interface is higher than that of the matrix silicon carbide.

Comparative example 1

In the comparison example, the materials to be connected are two silicon carbide materials with phi 20 multiplied by 20mm, the material of the connecting layer is a titanium silicon carbon cast film with the thickness of 50 μm, and the connecting interface reaches 1400 ℃ through electric field auxiliary connection, so that the silicon carbide materials to be connected are connected together. The method comprises the following specific steps:

(1) polishing the surface of the silicon carbide material to be connected to 2 microns by using diamond polishing solution, and removing defects and impurities on the surface;

(2) placing a 50-micron titanium silicon carbon cast film on the surface of silicon carbide, and butting the other piece of silicon carbide with the silicon carbide; and then putting the sample into a discharge plasma sintering furnace, electrifying, applying 50MPa axial pressure, heating to the furnace temperature of 1400 ℃ at the heating rate of 50 ℃/min, preserving the temperature for 10min, and then cooling to the room temperature at the speed of 50 ℃/min to obtain the silicon carbide connecting structure.

The microscopic morphology of the interface of the silicon carbide connection structure obtained in this comparative example was observed with a scanning electron microscope, and a back-scattering scanning electron micrograph is shown in fig. 8.

And cutting and polishing the obtained silicon carbide connecting structure to obtain a sample strip with the thickness of 4 multiplied by 3 multiplied by 40mm, testing the four-point bending strength of the sample strip by adopting a four-point bending method to be about 155Mpa, and breaking the sample strip on the interface titanium silicon carbon to show that the strength of a connecting layer is lower.

Compared with the embodiment of the invention, the titanium silicon carbon is taken as the connecting layer to connect the silicon carbide, and the thermal expansion coefficient of the titanium silicon carbon (about 9.2 multiplied by 10) is increased by the material of the connecting layer^-6K^-1) Is matrix silicon carbide (about 4.5X 10)^-6K^-1) 2 times of the connection structure, in the cooling process, the carbon, the silicon and the carbon in the connection layer can receive the action of tensile stress, and cracks are generated in the connection layer, so that on one hand, the connection structure is not beneficial to connection and sealing; on the other hand, the crack may become the weakest link in the connection structure. Meanwhile, the residual thermal stress can greatly reduce the mechanical properties of the silicon carbide connecting structure, such as the bending strength of only 155 MPa. In the invention, the Yt-Si-C connecting layer is obtained through the in-situ reaction between the lanthanide rare earth element Yb and the matrix silicon carbide, so that stronger interface chemical bonding is formed, and meanwhile, the ternary layered rare earth silicon carbide Yb is utilized₃Si₂C₂The silicon carbide and the liquid Yb are obtained by in-situ decomposition under the condition of high temperature instability, and on one hand, the liquid Yb can be further diffused into a crystal boundary and/or a pore of the silicon carbide at the connecting interface as a sintering aid, so that the connection and densification of the silicon carbide at the interface are promoted, and the local seamless connection can be realized; on the other hand, the precipitated silicon carbide has the same composition as the matrix phase, and there is no difference in thermal expansion coefficient, so that no crack occurs, and the flexural strength, the high temperature resistance, the oxidation resistance, and the corrosion resistance of the connection structure are not affected.

The aspects, embodiments, features and examples of the present invention should be considered as illustrative in all respects and not intended to be limiting of the invention, the scope of which is defined only by the claims. Other embodiments, modifications, and uses will be apparent to those skilled in the art without departing from the spirit and scope of the claimed invention.

The use of headings and chapters in this disclosure is not meant to limit the disclosure; each section may apply to any aspect, embodiment, or feature of the disclosure.

Throughout this specification, where a composition is described as having, containing, or comprising specific components or where a process is described as having, containing, or comprising specific process steps, it is contemplated that the composition of the present teachings also consist essentially of, or consist of, the recited components, and the process of the present teachings also consist essentially of, or consist of, the recited process steps.

Unless specifically stated otherwise, use of the terms "comprising", "including", "having" or "having" is generally to be understood as open-ended and not limiting.

It should be understood that the order of steps or the order in which particular actions are performed is not critical, so long as the teachings of the invention remain operable. Further, two or more steps or actions may be performed simultaneously.

In addition, the inventors of the present invention have also made experiments with other materials, process operations, and process conditions described in the present specification with reference to the above examples 1 to 12, and have obtained preferable results.

While the invention has been described with reference to illustrative embodiments, it will be understood by those skilled in the art that various other changes, omissions and/or additions may be made and substantial equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, unless specifically stated any use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.

Claims

1. A joining material for joining silicon carbide materials, characterized in that: the connecting material comprises Yb and Yb₃Si₂C₂Or Yb₃Si₂C₂Coating any one or the combination of more than two of the silicon carbide composite materials; superior foodOptionally, said Yb₃Si₂C₂The silicon carbide-coated composite material comprises Yb₃Si₂C₂And silicon carbide particles of Yb₃Si₂C₂Uniformly coating the surfaces of the silicon carbide particles; preferably, said Yb₃Si₂C₂Yb in silicon carbide-coated composite material₃Si₂C₂The content of (A) is 1-90 wt%; yb of the above₃Si₂C₂Selecting a casting film or Yb prepared by presintering₃Si₂C₂。

2.Yb、Yb₃Si₂C₂Or Yb₃Si₂C₂Use of a coated silicon carbide composite for joining silicon carbide materials.

3. Use according to claim 2, characterized in that it comprises: yb and Yb are arranged at the connecting interface of the silicon carbide materials to be connected₃Si₂C₂Or Yb₃Si₂C₂And coating the silicon carbide composite material, and heating to 700-1700 ℃ to combine the silicon carbide materials to be connected into a whole.

Preferably, the use comprises: the Yb film and Yb film are arranged at the connection interface of two silicon carbide materials to be connected₃Si₂C₂Or Yb₃Si₂C₂Coating a silicon carbide composite material; preferably, the thickness of the Yb film is less than 100 μm, preferably 50 to 500 nm; preferably, said Yb₃Si₂C₂Or Yb₃Si₂C₂The thickness of the coated silicon carbide composite material is less than 1mm, and preferably 0.5-500 mu m; preferably, said Yb₃Si₂C₂Selecting a casting film or Yb prepared by presintering₃Si₂C₂；

And/or the silicon carbide material comprises any one or the combination of more than two of silicon carbide fiber reinforced silicon carbide composite material, carbon fiber reinforced silicon carbide composite material, silicon carbide whisker reinforced titanium silicon carbon composite material, silicon carbide fiber reinforced titanium silicon carbon material and silicon carbide fiber reinforced titanium carbide material.

4. A method of joining silicon carbide materials, comprising: yb, Yb are arranged at the connecting interface of two silicon carbide materials to be connected₃Si₂C₂Or Yb₃Si₂C₂And coating the silicon carbide composite material, and heating to 700-1700 ℃ to combine the silicon carbide materials to be connected into a whole.

5. The connecting method according to claim 4, characterized by comprising: yb and Yb are arranged at the connecting interface of the silicon carbide materials to be connected₃Si₂C₂Or Yb₃Si₂C₂Coating a silicon carbide composite material; preferably, the thickness of the Yb film is less than 100 μm, preferably 50 to 500 nm; preferably, said Yb₃Si₂C₂Or Yb₃Si₂C₂The thickness of the coated silicon carbide composite material is less than 1mm, and preferably 0.5-500 mu m; preferably, said Yb₃Si₂C₂Selecting a casting film or Yb prepared by presintering₃Si₂C₂；

And/or the silicon carbide material comprises any one or the combination of more than two of silicon carbide fiber reinforced silicon carbide composite material, carbon fiber reinforced silicon carbide composite material, silicon carbide whisker reinforced titanium silicon carbon composite material, silicon carbide fiber reinforced titanium silicon carbon material and silicon carbide fiber reinforced titanium carbide material;

and/or the heating mode comprises a non-pressure heating connection, a hot pressing connection, an electric field auxiliary heating connection, a microwave field auxiliary heating connection or a laser heating connection, preferably the electric field auxiliary heating connection, the microwave field auxiliary heating connection or the laser heating connection.

6. A system for joining silicon carbide materials, comprising:

7. The system of claim 6, wherein: the thickness of the Yb film is less than 1 μm, preferably 50-500 nm; and/or, said Yb₃Si₂C₂Film or Yb₃Si₂C₂The thickness of the coated silicon carbide composite material film is less than 1mm, and preferably 0.5-500 mu m;

and/or the system further comprises a pressure device for providing a force that presses the two silicon carbide members against each other at the splicing interface;

and/or, the heating device comprises a hot pressing device;

and/or the heating device comprises an electric field auxiliary heating device or a microwave field auxiliary heating device;

and/or the heating device comprises a discharge plasma sintering furnace;

and/or the system further comprises an atmosphere control device and a vacuum pumping device;

and/or the system also comprises an infrared temperature measuring device;

and/or the outer sides of the two silicon carbide components are also provided with heat insulation structures.

8. A multilayer composite film structure for connecting silicon carbide materials is characterized in that the multilayer composite film structure is of a laminated structure along a set direction;

9. The multilayer composite film structure of claim 8, wherein:

the multilayer composite film structure comprises two Yb films, and at least two silicon carbide layers and at least two Yb films are arranged between the two Yb films₃Si₂C₂Film of silicon carbide layer and Yb₃Si₂C₂The membranes are alternately arranged along a set direction;

alternatively, the multilayer composite film structure comprises two Yb₃Si₂C₂Film, and the two Yb₃Si₂C₂At least two Yb films and at least one silicon carbide layer are arranged between the two Yb films, wherein one silicon carbide layer is distributed between the two Yb films;

and/or the thickness of the single-layer Yb film is less than 1 μm, preferably 50-500 nm, along the lamination direction of the multilayer composite film structure; and/or, a single layer of Yb in the stacking direction of the multilayer composite film structure₃Si₂C₂Film or Yb₃Si₂C₂The thickness of the coated silicon carbide composite material film is less than 1mm, and preferably 0.5 to 500 μm.

10. A connection structure between silicon carbide materials is composed of the silicon carbide materials to be connected and a connection material, wherein the connection material is arranged at the connection interface of the silicon carbide materials to be connected, and the silicon carbide materials to be connected are connected into a whole through the connection material in a heating connection mode of an external heat source, and the connection structure is characterized in that: the tie material is a multilayer composite film structure according to any one of claims 8 to 9.