JP7332145B2 - Method for producing titanium-based composite material - Google Patents

Description

The present invention relates to a method for producing a titanium-based composite material.

Titanium alloys are light, strong, and rust-resistant, which are ideal properties for structural materials. In the field of aviation, demand for titanium alloys is increasing year by year as materials for aircraft engines and airframe structures.

However, due to the low wear resistance of titanium, its excellent mechanical properties, and being an active metal, the production of titanium alloys is very complicated, requiring high energy and complicated manufacturing processes, Reduction of manufacturing cost and improvement of productivity are important issues.

On the other hand, composite materials are available as new materials to replace titanium alloys. A composite material is a material that is obtained by artificially combining two or more different materials and has properties that cannot be possessed by a single material.

Conventionally, titanium-based composite materials have been developed using an in-situ reaction. A composite material produced by an in-situ reaction has advantages such as high interfacial strength and excellent particle dispersibility because the reinforcing particles themselves are reaction products.

In addition, as titanium-based composite materials using in-situ reaction, titanium boride (TiB) dispersed composite materials aimed at improving the rigidity of titanium alloys, and titanium carbide (TiC) dispersed composite materials aimed at improving wear resistance. is being developed. The properties of these composite materials are much superior to those of conventional titanium alloys, and are attracting attention.

As disclosed in Non-Patent Document 1, there is a representative method for producing a titanium-based composite material using an in-situ reaction. In this manufacturing method, Ti powder, additive element powder, and AIB ₂ powder are mixed and then press-molded. After that, it is melted using a vacuum arc melting method, and TiB particles are crystallized in the matrix using an in-situ reaction. After casting and hot rolling, heat treatment is applied to improve mechanical properties.

J. Soc. Mat. Sci. , Japan, Vol. 47, No. 2, pp. 177-183, Feb. 1998 "Ductile Fracture of TiB Particle Reinforced Titanium Matrix Composites"

However, the above-described manufacturing method involves many manufacturing steps, requires high energy, and is costly, so it has been necessary to develop a low-cost manufacturing process.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a simple method for producing a titanium-based composite material using a solid-phase reaction between titanium and carbon.

In order to achieve the above objects, the present invention provides a method for producing a titanium-based composite material in which particulate titanium carbide is dispersed in a titanium matrix, comprising graphite powder, carbon nanofibers, or graphite powder and carbon nanofibers in a resin. A step of preparing a graphite sheet formed in a sheet form by dispersing a mixture of fibers and a plate-like titanium from which an oxide film has been removed, and laminating the graphite sheet between the plate-like titanium separated in the pressure direction by sandwiching the graphite sheet. A step of preparing a laminated sample, where the melting point of titanium is Mp (K), the laminated sample is pressed and held under a temperature condition of 973 K or higher and Mp or lower, thereby causing the graphite sheet to disappear. and a sintering step of dispersing titanium carbide particles.

In the present invention, the term "particles" means that the aspect ratio (horizontal-to-horizontal ratio) of titanium carbide in the titanium matrix is less than 3, and "particulate titanium carbide dispersed" means that such It means that titanium carbide having an aspect ratio of less than 3 is scattered in the titanium matrix without aggregating in one place.

Also, the melting point Mp of titanium is about 1941K.

According to the present invention, a graphite sheet obtained by dispersing graphite powder, carbon nanofibers, or a mixture of graphite powder and carbon nanofibers in a resin facilitates handling such as thickness control. The titanium carbide particles can be dispersed by applying a temperature and pressure around the phase transformation temperature of titanium (approximately 1158 K) to the laminated sample in which the graphite sheet is sandwiched between the titanium plates.

Solid-phase sintering is generally performed under temperature conditions of about 60 to 70% of the melting point of the solid. In the present invention, an α-type titanium-based composite material can be produced under temperature conditions of 973K or higher and Mp or lower. That is, the present invention can produce an α-type titanium-based composite material even under lower temperature conditions than conventional ones. The α-type titanium-based composite material produced in this way can have a higher hardness than that of pure titanium due to the dispersion of the titanium carbide particles.

Then, the laminated sample may be covered with a sheet-like β-stable element. The β-stable element is at least one selected from the group consisting of molybdenum, niobium, tantalum, vanadium, and rhenium.

By using the β-stable element, the phase of the titanium matrix can be easily changed. That is, it is possible to produce an α+β type titanium-based composite material by using a β-stable element. Since the α-type titanium and the α+β-type titanium have different characteristics, the phase transformation of titanium can be freely controlled to produce a titanium-based composite material according to the application.

According to the method for producing a titanium-based composite material of the present invention, when the graphite sheet is laminated between the plate-like titanium plates spaced apart in the pressure direction, and the melting point of titanium is Mp (K), the laminated sample is obtained. , under temperature conditions of 973 K or more and Mp or less, by applying and holding pressure, the graphite sheets disappear and the titanium carbide particles are dispersed, so that the α-type titanium-based composite material can be used even under lower temperature conditions than before. can be produced, unlike conventional titanium alloy production methods, complex heat treatment and high energy are not required, and energy can be saved by a simple production method. In addition, the titanium-based composite material produced in this manner exhibits improved hardness compared to pure titanium.

1 is a schematic diagram of a laminated sample according to an embodiment of the present invention; FIG. It is a schematic diagram of an electric discharge baking machine. It is a graph which shows the voltage waveform of an electric discharge baking machine, and a sintering process. 4 is a table showing sintering conditions of Comparative Example 1 and Examples 1-4. 4 is a photograph of a longitudinal section of a titanium-based composite material according to Comparative Example 1. FIG. 1 is a photograph of a longitudinal section of a titanium-based composite material according to Example 1. FIG. 4 is a photograph of a longitudinal section of a titanium-based composite material according to Example 2. FIG. 3 is a photograph of a longitudinal section of a titanium-based composite material according to Example 3. FIG. 10 is a photograph of a longitudinal section of a titanium-based composite material according to Example 4. FIG. 1 is a schematic diagram of a longitudinal section of a titanium-based composite material according to Comparative Example 1. FIG. 1 is a schematic diagram of a longitudinal section of a titanium-based composite material according to Example 1. FIG. FIG. 2 is a schematic diagram of a longitudinal section of a titanium-based composite material according to Example 2; 3 is a schematic diagram of a vertical cross section of a titanium-based composite material according to Example 3. FIG. FIG. 10 is a schematic diagram of a longitudinal section of a titanium-based composite material according to Example 4; It is a BSE image in the X part of FIG. 6C. It is a BSE image of titanium atoms in the X part of FIG. 6C. FIG. 6C is a BSE image of carbon atoms in the X part of FIG. 6C. It is a BSE image in the Y part of FIG. 6E. It is a BSE image in the Z section of FIG. 6E. 4 is an FE-SEM image of a titanium-based composite material according to Example 4. FIG. FIG. 10 is spectral data showing the results of point analysis of the dark gray particles located in the center of FIG. 9 ; FIG. 4 is a BSE image of a titanium-based composite material according to Example 4. FIG. 10 is a photograph of a longitudinal section of a titanium-based composite material according to Example 5. FIG. 10 is a BSE image of a titanium-based composite material according to Example 5. FIG. 13 is a BSE image in the W part of FIG. 12. FIG. 13 is a BSE image of titanium atoms in the W portion of FIG. 12. FIG. It is a BSE image of carbon atoms in the W part of FIG. 4 is a graph showing the relationship between sintering temperature and Vickers hardness.

Hereinafter, embodiments of the present invention will be described in detail. The following description of the embodiments is merely illustrative in nature, and is not intended to limit the invention, its applications, or its uses.

FIG. 1 is a schematic diagram of a laminated sample 10 of a titanium-based composite material according to an embodiment of the present invention. The laminate sample 10 consists of a graphite sheet 2 formed in a sheet shape by dispersing graphite powder, carbon nanofibers, or a mixture of graphite powder and carbon nanofibers in a resin, and plate-like titanium 3 from which an oxide film has been removed. Graphite sheet 2 is sandwiched between titanium plates 3, 3 spaced apart in the direction of pressure and laminated.

The graphite sheet 2 is made by dispersing graphite powder, carbon nanofibers, or a mixture of graphite powder and carbon nanofibers in a resin and forming it into a sheet shape, and preferably has a thickness of 40 to 50 μm. In this embodiment, graphite powder having an average particle size of about 3 μm and a density of 2.26 was used. The type of graphite is called earthy graphite, which has good compatibility with liquids and is used for paints and the like. Using such graphite powder, a graphite sheet having a thickness of about 40 μm was used.

The plate-like titanium 3 is made of pure titanium with a purity of 99% or more, and in this embodiment, a plate-like titanium with a thickness of about 1 mm is used. Titanium is highly reactive with oxygen and tends to form an oxide film on its surface. Since the oxide film impedes the diffusion of carbon, it is necessary to remove the oxide film before lamination.

Here, the types of phases of the titanium alloy will be explained. Titanium has an hcp structure (α phase) at low temperatures, but undergoes a phase transformation to a bcc structure (β phase) at 1158K or higher. The α phase is excellent in strength, but has the drawback of being inferior in ductility and workability. On the other hand, the β phase is excellent in ductility and workability, so that it can be worked into various shapes, but has the disadvantage of being inferior in strength. Therefore, in practice, the amount ratio and structure of the α phase and β phase are controlled according to the application.

The most important method of phase control is the addition of elements. When an element is added to titanium, the stability region of α-phase and β-phase changes depending on the element. By adding elements called α-phase stable elements such as aluminum, gallium, tin, carbon, oxygen, and nitrogen, the transformation temperature rises and the α-phase stable region expands. In contrast, by adding elements called β-stable elements such as molybdenum, niobium, tantalum, vanadium, and rhenium, the transformation temperature is lowered and the stable region of the β phase is expanded. In an embodiment of the present invention, the additive element used is α-phase stable carbon, and the transformation temperature of titanium rises to 1195K.

Types of titanium alloys are roughly classified into three types, α-type titanium alloys, β-type titanium alloys, and α+β-type titanium alloys, depending on the state of the metal structure at room temperature. These properties can be changed by heat treatment, and the properties can be changed by changing the structure. The α phase has a hexagonal close-packed structure, and the β phase has a body-centered cubic structure.

The α-type alloy has excellent corrosion resistance, heat resistance, and high-temperature creep characteristics, so it is resistant to brittle fracture even in high-temperature and low-temperature environments, and has stable strength from low to high temperatures. However, no improvement in strength by heat treatment can be expected, and the strength is not as strong as α+β type alloys and β type alloys. It is mainly used in aircraft engine materials and aircraft high-temperature components because it exhibits excellent properties even in high-temperature environments.

β-type alloys are said to have the highest strength among titanium alloys, and because they have many slip planes due to the body-centered cubic lattice structure of the β-phase, they have superior workability compared to other titanium alloys. There are advantages. It is mainly used for sports leisure and consumer goods, taking advantage of its strength.

The α+β type alloy is a representative alloy of titanium that combines the properties of the α type alloy and the β type alloy in a well-balanced manner. ing. A drawback is the low wear resistance. It is mainly used in a wide range of fields such as aircraft, medical, space industry and sports and leisure.

In the embodiment of the present invention, the phase transformation of titanium can be controlled by the presence or absence of a β-stable element, and an α-type titanium-based composite material or an α+β-type titanium-based composite material can be freely produced.

[Method for producing titanium-based composite material]
Next, a method for producing a titanium-based composite material according to an embodiment of the present invention will be described.

A composite material is produced in three stages: (1) material preparation process, (2) laminated sample preparation process, and (3) acid sintering process.

(1) Material preparation step First, in the preparation step, a graphite sheet 2 formed in a sheet shape by dispersing graphite powder, carbon nanofibers, or a mixture of graphite powder and carbon nanofibers in a resin, and an oxide film were removed. A sheet of titanium 3 is prepared.

Specifically, the graphite sheet 2 is prepared by mixing 0.625 g of graphite powder (manufactured by Nishimura Graphite Co., Ltd.) with 12.5 g of a polyvinyl alcohol aqueous solution (manufactured by Yamato Co., Ltd., Arabic Yamato (registered trademark)) and stretching it into a thin sheet. It was prepared by drying. The thickness of the finished graphite sheet 2 was about 40 μm. Then, it was cut into a circular shape with a diameter of 10 mm according to the mold. By forming the graphite powder into a sheet, it is possible to prevent it from flowing out of the mold, to achieve uniformity, and to improve workability.

The plate-like titanium 3 is pure titanium (manufactured by Seizaemon Hirano, JIS class 1) having a thickness of about 1 mm, and two pieces of φ110 mm circular pieces are prepared. Then, the oxide film was removed by lightly scraping each piece with #2000 abrasive paper, and immediately after that, the pieces were immersed in acetone in a petri dish to suppress the oxidation reaction.

(2) Laminated Sample Production Process Next, as shown in FIG. 1, a laminated sample 10 was produced by laminating the graphite sheet 2 between the titanium plates 3, 3 spaced apart in the pressure direction.

Specifically, a mold made of graphite (ISO63) having an outer diameter of 40 mm, an inner diameter of 10 mm, and a height of 60 mm was used. The inside of the mold was coated with LBN spray (manufactured by Showa Denko Co., Ltd., components: methyl ethyl ketone, dimethyl ether, isopropyl alcohol, nitrocellulose) to prevent graphite from reacting and to release the sintered body. Then, the titanium plate 3, the graphite sheet 2, and the titanium plate 3 were laminated in this order from the bottom of the mold upward to prepare a laminate sample 10. FIG.

The laminated sample 10 is not limited to having only one graphite sheet 2 as shown in FIG. It may be laminated on.

(3) Sintering Step Then, the laminate sample 10 was pressed and held under a predetermined temperature condition to eliminate the graphite sheet 2 and to disperse the titanium carbide particles.

This sintering step will be specifically described below. The method of pressure sintering is not particularly limited, and includes hot casting, discharge plasma sintering, and the like. In this embodiment, a discharge plasma sintering method is used.

FIG. 2 is a schematic diagram of an electric discharge sintering machine. The discharge sintering machine has two modes: mode 1 for pre-sintering and mode 2 for resistance sintering. In mode 1, DC pulse energization is performed, and in mode 2, continuous energization is performed. FIG. 3 shows voltage waveforms and sintering processes in Modes 1 and 2. Current flows from the top electrode to the bottom electrode. Both electrodes are made of stainless steel, the upper electrode is fixed, and the lower electrode is a uniaxial compression mechanism that is attached to a hydraulic cylinder and can move up and down. The temperature was measured by connecting a thermocouple inserted into the sintering mold to a pen recorder. The load current between both electrodes was detected by measuring the shunt voltage.

As pre-sintering, current was applied directly to the sintering mold and laminated sample 10 for 600 seconds at a pulse current of 100 A, a pulse voltage of 50 V, and a pulse width of 100 ms 1 . Thereafter, the temperature was raised to a predetermined sintering temperature by continuous energization for main sintering, and the temperature was maintained for 600 seconds for sintering to prepare a titanium-based composite material.

[Consideration of sintering temperature]
FIG. 4 shows the sintering conditions of Comparative Example 1 and Examples 1-4. In Comparative Example 1 and Examples 1 to 4, laminate samples 10 were produced in the same manner as described above. The sintering temperature was 873K in Comparative Example 1, 973K in Example 1, 1073K in Example 2, 1173K in Example 3, and 1273K in Example 4.

After the sintering process, the sample is cut in the pressure direction (vertical direction) using a fine cutter, and the cross section of the titanium-based composite material is observed using a scanning electron microscope (JEOL, SEM, JXA-8900RL). went.

Photographs of tissue observation surfaces are shown in FIGS. 5A-E, and corresponding schematic diagrams of tissue observation surfaces are shown in FIGS. 6A-E. As shown in FIGS. 5A and 6A, in Comparative Example 1 in which the sintering temperature was 873K, unreacted graphite sheet 2 remained as it was. It was found that at a sintering temperature of 873K, carbon does not undergo a solid state reaction with titanium.

As shown in FIGS. 5B and 6B, in Example 1 in which the sintering temperature was 973 K, the graphite sheet 2 disappeared due to the solid-phase reaction between carbon and titanium, and the upper and lower titanium plates 3, 3 were joined. The bonding rate was about 20%.

As shown in FIGS. 5C-E and 6C-E, the bonding area increased as the sintering temperature increased. In Example 2 (Figs. 5C and 6C) in which the sintering temperature was 1073K, the bonding rate was about 50%. It was about 95% in Example 4 (FIGS. 5E and 6E).

Furthermore, in order to investigate the solid-phase reaction structure of titanium and carbon, structure observation and surface analysis were performed using the titanium-based composite material produced at a sintering temperature of 1073 K (Example 2). What was analyzed is the X portion in FIG. 6C. Unreacted graphite sheet 2 remained in the X portion, and surface analysis was performed on this with an electron probe microanalyzer (manufactured by JEOL, EPMA, JXA-8900RL). The results are shown in FIGS. 7A-C.

FIG. 7A is a backscattered electron image (hereinafter referred to as a BSE image) in the X section of FIG. 6C. FIG. 7B is a BSE image of titanium atoms in the X part of FIG. 6C. And FIG. 7C is a BSE image of carbon atoms in the X part of FIG. 6C.

As shown in FIG. 7A, from the result of surface analysis, it was confirmed that the black part in the X part of FIG. 6C was unreacted graphite sheet 2 . Moreover, in FIG. 7A, there were dark gray portions above and below the unreacted graphite sheet 2 . The dark gray part was presumed not to be unreacted graphite powder, since a clear color difference occurred in the BSE image when compared with the graphite sheet 2 part. Moreover, as shown in FIGS. 7B and 7C, peaks of both titanium and carbon were detected, so it can be assumed that the dark gray portion is titanium carbide. Due to the reaction between titanium and carbon, titanium carbide was dispersed on the plate-like titanium 3 side.

From the above results, the laminated sample 10 in which the graphite sheet 2 is sandwiched between the titanium plates 3 and 3 is pressed and held at a sintering temperature of 973 K or higher to eliminate the graphite sheet 2 and carbonize it. Titanium particles can be dispersed. In order to prevent the plate-like titanium 3 from melting, the firing temperature is lower than Mp (K), where Mp (K) is the melting point of titanium. Note that the melting point of titanium is about 1941K.

[Tissue observation]
In order to analyze the difference in titanium carbide formation depending on the location of the matrix, the titanium-based composite material of Example 4 produced at a sintering temperature of 1273 K was examined at the sample center where graphite sheet 2 was present and at the sample center where graphite sheet 2 was present. A scanning electron microscope (SEM) was used to observe each upper portion of the sample away from the place where it had been observed.

FIG. 8A is a BSE image at the Y portion of FIG. 6E, and FIG. 8B is a BSE image at the Z portion of FIG. 6E.

As shown in FIG. 8A, the upper portion of the titanium-based composite material of Example 4 was dotted with carbon atoms. Since the mold is made of graphite, there was a risk that carbon would enter the mold during sintering, but the carbon was scattered in areas near the mold in the same way as in other areas. , it was confirmed that the diffusion of carbon from the mold did not affect the formation of titanium carbide.

As shown in FIG. 8B, in the titanium-based composite material of Example 4, carbon was found to be scattered even in the portion where the graphite sheet 2 was present.

However, since the titanium carbide particles are ultrafine, the presence of the titanium carbide particles could not be confirmed in the SEM image. In order to analyze the titanium carbide particles produced in the matrix, the titanium-based composite material of Example 4 produced at a sintering temperature of 1273 K was subjected to a field emission scanning electron microscope (FE-SEM, S- 5200) was used to observe the structure at 20,000 times.

9 is an FE-SEM image of the titanium-based composite material according to Example 4. FIG. The location where the observation was performed is the central part of the sample. As shown in FIG. 9, it was confirmed that dark gray particles were present in the central portion. FIG. 10 is spectral data showing the results of point analysis of dark gray particles. As shown in FIG. 10, it was confirmed that the dark gray particles in FIG. 9 were titanium carbide. Also, from the FE-SEM image of FIG. 9, the diameter of the titanium carbide particles was about 1 μm.

[Control of matrix phase using β-stable element]
11 is a photograph of the Z portion in FIG. 6E, which is a BSE image of the cross-sectional central portion of the titanium-based composite material according to Example 4. FIG. As shown in FIG. 11, in the titanium-based composite material according to Example 4, most of the matrix structure was granular α-phase.

Therefore, in order to improve the phase stability of the matrix, we investigated using molybdenum, which is a β-stable element.

Specifically, first, a laminated sample 10 was prepared in the same manner as in Examples 1-4. A sheet of molybdenum (manufactured by Nicolas, thickness: about 0.05 mm, purity: 99.95%) was wrapped around the entire outer periphery of the laminated sample 10 and sintered (Example 5). The sintering conditions were the same as in Example 4, i.e., a sintering temperature of 1273 K, a pressure of 50 MPa, and a holding time of 600 seconds.

After the sintering step, the fine cutter was used to cut the sample in the pressure direction (vertical direction) in the same manner as in Examples 1 to 4, and the cross section of the titanium-based composite material was observed using an SEM.

FIG. 12 is a photograph of a longitudinal section of the titanium-based composite material according to Example 5 by SEM. As shown in FIG. 12, no unreacted graphite sheet 2 was observed after sintering, confirming that wrapping molybdenum does not affect sinterability.

13 is a photograph of the W portion in FIG. 12, which is a BSE image of the cross-sectional central portion of the titanium-based composite material according to Example 5. FIG. As shown in FIG. 13, it was confirmed that the titanium-based composite material according to Example 5 was composed of an α+β phase in which a granular α phase structure and an acicular β phase structure were mixed.

By covering the outer periphery of the laminated sample 10 with a sheet of molybdenum, which is a β-stable element, and sintering, the titanium matrix phase of the titanium-based composite material can be α + β titanium. α+β-titanium has well-balanced characteristics of α-titanium and β-titanium, and can be applied as a highly functional titanium-based composite material in more fields.

In Example 5, an α + β type titanium-based composite was produced at a sintering temperature of 1273 K, but in other temperature ranges where titanium-based composite materials can be produced, a titanium phase using a β-stable element was also produced. Control is possible. β-stable elements other than molybdenum, such as niobium, tantalum, vanadium, and rhenium, may also be used.

Since the α-type titanium and the α+β-type titanium have different characteristics, the phase transformation of titanium can be freely controlled to produce a titanium-based composite material according to the application.

Further, the presence of titanium carbide in the titanium-based composite material according to Example 5 was confirmed. 14A to 14C are BSE images showing the results of surface analysis using EPMA on the W portion in FIG. As shown in FIG. 4A, black particles are scattered. FIG. 14B is the result of analyzing titanium atoms, and FIG. 14C is the result of analyzing carbon atoms. According to FIGS. 14B and C, the black particles scattered in FIG. 14A can be identified as titanium carbide.

[Evaluation of Vickers hardness]
Next, a micro-Vickers hardness test was performed to analyze the effect of titanium carbide particles on the hardness of the titanium-based composite material. A Vickers hardness tester (FV-110, manufactured by Futuretech Co., Ltd.) was used to evaluate the Vickers hardness. The hardness was measured at 10 points under the conditions of a test load of 30 N and a load time of 10 s, and the average value was calculated.

Three kinds of titanium-based composite materials of Example 2 (sintering temperature 1073 K, no molybdenum sheet), Example 4 (sintering temperature 1273 K, no molybdenum sheet), and Example 5 (sintering temperature 1273 K, with molybdenum sheet). were each subjected to a micro Vickers hardness test.

FIG. 15 is a graph showing the relationship between sintering temperature and Vickers hardness. Incidentally, the Vickers hardness of pure titanium is 123.5 Hv. As shown in FIG. 15, Vickers hardness was increased in all samples compared to pure titanium. Among them, Example 4 has the highest hardness, which is about 76% higher than that of pure titanium.

The titanium-based composite material of the present embodiment produced as described above has hardness higher than that of pure titanium. This is believed to be due to the dispersion of titanium carbide.

INDUSTRIAL APPLICABILITY The present invention can be industrially applied as a method for producing a titanium-based composite material applicable to various fields including the field of aviation.

10 Laminated Sample 2 Graphite Sheet 3 Plate Titanium

Claims (3)

A method for producing a titanium-based composite material in which particulate titanium carbide is dispersed in a titanium matrix, comprising:
preparing a graphite sheet formed by dispersing graphite powder, carbon nanofibers, or a mixture of graphite powder and carbon nanofibers in a resin, and plate-like titanium from which an oxide film has been removed;
a step of preparing a laminated sample in which the graphite sheet is sandwiched between the titanium plates spaced apart in the pressure direction;
When the melting point of titanium is Mp (K) , pressure is applied to the laminated sample in the lamination direction and held under a temperature condition of 973 K or higher and Mp or lower, whereby the graphite sheet disappears, a sintering step of dispersing titanium carbide particles;
A method for producing a titanium-based composite material, comprising: 2. The method for producing a titanium-based composite material according to claim 1, wherein the laminated sample is covered with a sheet-like β-stabilizing element. 3. The method for producing a titanium-based composite material according to claim 2, wherein the β-stabilizing element is at least one selected from the group consisting of molybdenum, niobium, tantalum, vanadium, and rhenium.

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