KR20180025033A - Rhenium-carbon composite and manufacturing method for the same - Google Patents

Abstract

The present invention relates to a rhenium-carbon composite and to a manufacturing method thereof, wherein the rhenium-carbon composite comprises the following steps: a) processing a carbon-carbon composite reinforced with carbon fibers so that the carbon fibers have a specific angle with respect to the joining direction; b) forming a buffer layer between the carbon-carbon composite and rhenium; c) disposing rhenium in a lower portion of the carbon-carbon composite; and d) curved surface-bonding the carbon-carbon composite, a buffer layer and the rhenium by a high-temperature and high-pressure sintering method. Another object is to solve the non-uniformity of the metal-ceramic bonding occurring at the high-temperature pressure bonding through the selection of a proper ceramic base material and pressure bonding conditions.

Description

TECHNICAL FIELD [0001] The present invention relates to a rhenium-carbon composite material,

The present invention relates to a rhenium-carbon composite material using high-temperature sintering and a method for producing the same.

Due to the rapid increase of high energy related industries in the 21st century, demand for materials with good strength in ultra-high temperature environment is increasing day by day. Especially, in the advanced industrialized countries, which occupy more than 70% of the global market, the aerospace industry is required to invest in large-scale facilities and research and development, and pursue with a clear purpose such as fostering the export industry and high-tech industry, Industry. Among the fields of the aerospace industry, the manufacturing technology of composites applicable to heat-resistant structures and propulsion engines (combustors / nozzles, etc.) of space launch vehicles is not limited to manufacturing technology, but also to technical support for strict control of raw material, manufacturing process, Barriers are high technology.

Since the variable thruster part of the propulsion machinery needs to precisely control the combustion gas of the actuator that receives the induction steering task, the valve housing and the pintle / nozzle, which are components of the variable thruster, have the greatest importance in ensuring stability under extremely high temperature and high pressure environments. In order to use the material at high temperature, the melting point of the material must first be high and the mechanical strength at high temperature must be maintained. Rhenium in heat-resistant metal is one of the metals with the highest melting point (3186 ℃) in metal. It is a typical material produced by powder metallurgy process. It maintains hardness and strength even at high temperature and has excellent thermal shock resistance, high temperature strength and abrasion resistance. However, due to the high density (21.02 g / cm ² ), it is difficult to reduce the weight of parts. In order to solve this problem, a ceramic composite material reinforced with ceramic fibers has been attracting attention, and non-oxide ceramic matrix composites such as SiC reinforced with carbon fiber or SiC fiber Composite materials (SiCf / SiC composite) have attracted attention as candidates and they are required to be combined with non-oxide ceramics reinforced with high melting point metal and ceramic fiber.

Many researches have been made on the heterogeneous bonding technology used for the composite of metal-ceramic materials in the production of simplified flat plate type junctions. However, there is a problem in that the bonding strength is not constant due to strain / stress applied to the base material at the time of pressurization as well as the coefficient of thermal expansion and surface processing between the bonding materials in producing a composite body having a composite shape.

The present invention is directed to solving the above-mentioned problems and other problems. Another object of the present invention is to solve the non-uniformity of the metal-ceramic bonding occurring in the high-temperature pressurized bonding by selecting the proper ceramic base material and press bonding conditions.

According to an aspect of the present invention, there is provided a method of manufacturing a carbon fiber composite material, comprising the steps of: a) preparing a carbon-carbon composite reinforced with carbon fiber, step; b) forming a buffer layer between the carbon matrix material and rhenium; c) disposing rhenium in the lower portion of the carbon matrix composite; And d) curving the carbon matrix composite material, the buffer layer and the rhenium using a high-temperature sintering method, thereby forming a rhenium-carbon composite material.

According to an aspect of the present invention, the buffer layer may include at least one of Ti (Titanium), Zr (Zirconium), Ta (Tantalum) or Mo (Molybdenum).

According to an aspect of the present invention, the high-temperature sintering method may be performed in a graphite mold, and the method may further include coating the graphite mold with boron nitride powder.

According to an aspect of the present invention, the buffer layer may be a carbonized layer formed by bonding at least one of Ti (Titanium), Zr (Zirconium), Ta (Tantalum) or Mo (Molybdenum) have.

According to an aspect of the present invention, there is provided a carbon fiber composite material, comprising: a carbon-carbon composite reinforced with carbon fiber; a buffer layer formed between the carbon matrix composite material and rhenium; Wherein the carbon fibers are formed so as to have a specific angle with respect to the joining direction of the rhenium-carbon composite material.

According to an aspect of the present invention, the buffer layer is a carbonized layer formed by bonding at least one of Ti (Titanium), Zr (Zirconium), Ta (Tantalum), or Mo (Molybdenum) .

The effects of the rhenium-carbon composite material according to the present invention and the manufacturing method thereof will be described below.

According to at least one of the embodiments of the present invention, there is an advantage that a composite material having sufficient heat resistance and wear resistance even at a temperature of 2000 ° C or higher can be produced by using the high-temperature sintering method for metal-ceramic bonding. Further, there is an advantage that the ceramic and the metal can be bonded by pressurization at a high temperature without melting.

According to at least one of the embodiments of the present invention, the use of a carbon-carbon composite as a base material instead of Re is advantageous in terms of cost reduction because it can reduce the weight of the joined body and the proportion of expensive expensive heat-resistant metal Rhenium.

In addition, according to at least one embodiment of the present invention, by using Ti as an intermediate layer between metal and ceramic, a carbonized layer such as TiC is generated between carbon-carbon composites to alleviate a high temperature impact due to a difference in thermal expansion coefficient, There is an advantage that bonding can occur and a stable bonding layer can be retained.

Further scope of applicability of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and specific examples, such as the preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art.

1 is a schematic diagram of a high-temperature press-bonding experiment related to an embodiment of the present invention.
Figure 2 is a flow diagram of a bonding process in accordance with one embodiment of the present invention.
3 is an SEM image of a cross-section of a conjugate prepared according to one embodiment of the present invention.
4 is an image and elemental analysis graph of Re / Ti / Carbon-carbon composite intermediate layer according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. , ≪ / RTI > equivalents, and alternatives.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a joining technique for joining ceramic and metal as a base material by pressurizing at a high temperature without melting. In general, metals and ceramics affect the properties of the bonded body due to various physical properties as well as thermal expansion coefficient.

In an embodiment of the present invention, the ceramic material and the metal are not particularly limited. However, in order to expect the heat resistance at a temperature higher than 2000 ° C, the ceramic material is a carbon-carbon composite reinforced with carbon fiber, Etc. are used as a base material, but the present invention is not limited thereto.

In an embodiment of the present invention, the carbon fiber and the bonding surface form a certain angle in order to solve the anisotropy in the bonding direction of the ceramic base material. Rhenium, which is excellent in high temperature impact resistance, high temperature strength, abrasion resistance, etc., is preferable, but not limited thereto, because the bonding metal used in the external oxidizing environment maintains high hardness and strength at high temperature.

For the stable bonding of metal-ceramics, metal materials such as Ti, Zr, Ta, and Mo were used as a buffer layer between Re and the ceramic composite material. A carbonized layer such as TiC is generated between the buffer layer and the base material (carbon-carbon composite) to alleviate the high temperature impact due to the difference in the thermal expansion coefficient, and diffusion bonding occurs to secure a stable bonding layer.

In an embodiment of the present invention, these factors are taken into account because the bonding of the metal and the ceramic may have a difference in the bonding form of the atoms at the interface of the thermal expansion coefficient, the elastic modulus, and the conversion rate of the reactive element.

Also, when there is a reaction between the metal and the ceramic, the kind of the reaction phase and the growth rate of the layer affect the bonding. In the early stage of bonding, these chemical reactions form a chemical bond and increase the bonding strength. However, in an excessive time and high temperature conditions, the chemical bond is developed and the reaction product layer Or at the interface between the reaction product layer and the base material, the bonding strength is lowered.

Therefore, in one embodiment of the present invention, metal-ceramic bonding between Rhenium and carbon-carbon composite having sufficient heat resistance and abrasion resistance at an ultra-high temperature, that is, at a temperature of 2000 ° C or more, is provided by using a high-temperature pressure sintering method . When a metal is applied only to a heat-resistant structure requiring a high-temperature combustion gas control and a propulsion engine, cracks and creep rupture due to high-temperature impacts are generally exhibited. Therefore, this problem can be solved through bonding with ceramics .

It has a wide bonding area by bonding the carbon fibers of the carbon-carbon composite with the bonding surface while maintaining a specific angle. By preventing the strain / stress of the ceramic base material due to the anisotropy of the carbon fiber during pressure sintering, Thereby maintaining the bonding.

In addition, by using Ti as an intermediate layer between metal and ceramics, a carbonized layer such as TiC is generated between the carbon-carbon composite, thereby relieving the high-temperature impact due to the difference in thermal expansion coefficient, resulting in diffusion bonding and a stable bonding layer. Respectively.

Hereinafter, embodiments of the present invention will be described in more detail.

FIG. 1 is a schematic diagram of a high-temperature pressurized bonding test according to an embodiment of the present invention, and FIG. 2 is a flow chart of a bonding process according to an embodiment of the present invention, which will be described below with reference to FIGS. 1 and 2.

First, the carbon-carbon composite, Ti, and Re are machined to conform to the joining reduction model, and then fixed to the joining order as shown in FIG. First, a carbon-carbon composite reinforced with a carbon fiber is fabricated (S110) so that the carbon fibers have a specific angle with the joining direction.

Thereafter, a buffer layer is formed between the carbon-based complex material and rhenium (S120). The buffer layer may be formed of one of Ti, Zr, Ta, It is formed by bonding with carbon.

Then, Rhenium is disposed on the lower portion of the carbon matrix composite material (S130), and the carbon matrix composite material, the buffer layer, and the rhenium are subjected to curved surface bonding (S140) using a high-temperature sintering method.

In this case, when the high-temperature sintering method is performed on a graphite mold, the boron nitride powder is uniformly coated to prevent the reaction between graphite and rhenium (Re) at high temperature, Put it in a graphite mold.

Then, the carbon base composite material, the buffer layer and the rhenium were heated to 600 ° C in an argon atmosphere, and then heated to 1600 ° C in a pressure state of about 20 MPa for 2 hours. After reaching 1600 ° C, the pressure is increased to 25 MPa and heat treatment is performed for 2 hours. After the heat treatment, maintain the pressure of 25 MPa until reaching 600 ℃ and maintain the pressure of 20 MPa to room temperature.

At this time, the order of the above-described manufacturing method is not necessarily based on the above-described steps (S110 to S140), and the high-temperature sintering process can be performed regardless of the above procedure.

The foregoing detailed description should not be construed in all aspects as limiting and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

Claims (6)

a) processing a carbon-carbon composite reinforced with carbon fiber so that the carbon fibers have a certain angle with respect to the joining direction;
b) forming a buffer layer between the carbon matrix material and rhenium;
c) disposing rhenium in the lower portion of the carbon matrix composite; And
and d) curving the carbon-base matrix material, the buffer layer, and the rhenium using a high-temperature sintering method. The method according to claim 1,
Wherein the buffer layer comprises at least one of Ti (Titanium), Zr (Zirconium), Ta (Tantalum) or Mo (Molybdenum). 3. The method of claim 2,
The high-temperature sintering method is performed in a graphite mold,
And coating the graphite mold with boron nitride powder. ≪ RTI ID = 0.0 > 11. < / RTI > 3. The method of claim 2,
Wherein the buffer layer is a carbonized layer formed by bonding at least one of Ti (Titanium), Zr (Zirconium), Ta (Tantalum) or Mo (Molybdenum) with carbon of the carbon matrix resin. Gt; A carbon-carbon composite reinforced with carbon fiber, a buffer layer formed between the carbon matrix composite and rhenium, and rhenium formed under the carbon matrix composite, ,
Wherein the carbon fibers are formed to have a specific angle with the bonding direction. 6. The method of claim 5,
The buffer layer may be formed,
Carbon composite formed by bonding at least one of Ti (Titanium), Zr (Zirconium), Ta (Tantalum) or Mo (Molybdenum) with carbon of the carbon matrix resin.

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