Titanium-based composite material and foil preparation method thereof
By combining low-temperature vacuum sintering and hot isostatic pressing with mechanical cutting and precision machining, the problem of preparing high-modulus titanium-based composite foils was solved, and the preparation of high-performance ultrathin foils was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-14
- Publication Date
- 2026-03-24
AI Technical Summary
Existing technologies struggle to produce high-modulus titanium-based composite foils, resulting in high production costs, long production cycles, poor overall performance, and difficulties in fabricating ultrathin foils.
High-modulus titanium-based composite foils were prepared by combining a synergistic process of low-temperature vacuum sintering and uncoated hot isostatic pressing with a composite process of mechanical cutting for thinning, hot rolling with coating, grinding and polishing.
The preparation of high-density, high-performance titanium-based composite material bulk materials has been achieved, solving the problem of preparing high-modulus titanium-based composite materials and obtaining ultra-thin foil materials with a thickness of 0.1 mm to 0.2 mm, smooth surface, and good flatness.
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Figure CN121715437A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of metal matrix composite materials and powder metallurgy technology, specifically relating to a titanium-based composite material and its foil preparation method. Background Technology
[0002] Titanium alloys, due to their superior properties such as high specific strength, high hardness, high wear resistance, and corrosion resistance, while having a lower density compared to stainless steel, have been widely used in various fields in recent years. However, as the requirements for materials in high-precision fields become increasingly demanding, the inherent properties of titanium alloys are gradually becoming insufficient to meet performance requirements. Titanium-based composite materials prepared by adding reinforcing phase particles exhibit higher strength and stiffness, possessing better overall performance. Furthermore, due to the extreme demands for lightweighting and miniaturization in aerospace, electronic devices, and other fields, the need for ultra-thin, high-strength, and high-modulus titanium-based composite foils is particularly urgent. However, obtaining foils that meet these requirements presents dual challenges from material design to fabrication and processing.
[0003] First, in terms of material design, most reported titanium-based composite materials have relatively low reinforcing phase content, making it difficult to meet the application requirements for high modulus. Second, the performance of high-modulus titanium-based composite materials is closely related to the preparation process, and existing preparation methods have inherent defects. Among the common preparation methods for titanium-based composites, vacuum sintering has a simple process flow. However, due to the low preparation pressure, it is difficult to achieve complete densification of the powder under normal conditions. Especially after adding a higher content of reinforcing phase particles to the titanium matrix, the sintering density will further decrease, and the residual pores inside may become crack sources, making it difficult to prepare high-modulus titanium-based composites with excellent comprehensive performance. The preparation of titanium-based composites by hot isostatic pressing requires loading the uniformly mixed titanium / titanium alloy powder and reinforcing phase particles into a metal cladding. The cladding material is usually stainless steel or titanium / titanium alloy. At the same time, the metal cladding needs to undergo a long-term vacuum degassing treatment to fully remove the gas inside the cladding. Otherwise, it is difficult to achieve complete densification of the powder. In addition, the stainless steel cladding will undergo a severe eutectic reaction with the titanium matrix at around 1085℃, and iron and titanium will form brittle intermetallic compounds. Therefore, there is a significant preparation risk under the high temperature and high pressure environment of hot isostatic pressing. If a titanium cladding is used, it will further increase the material preparation cost.
[0004] After preparing the bulk composite material, processing it into ultrathin foils that meet application requirements presents even greater challenges. Specifically, although there are many reported methods for preparing titanium alloy foils, there is no stable method specifically for preparing high-modulus titanium-based composite foils. Currently, titanium alloys are typically produced by cold rolling to obtain foils with a thickness of less than 0.20 mm. However, the addition of reinforcing phase particles greatly increases the processing difficulty of titanium-based composites, making it difficult to produce titanium-based composite foils with a thickness of <0.20 mm using traditional cold rolling processes. At the same time, hot rolling makes the titanium matrix highly susceptible to reaction with oxygen and nitrogen, generating a hard and brittle oxide scale that affects surface quality, and temperature fluctuations lead to extremely imprecise dimensional control. Summary of the Invention
[0005] In view of the above problems, this application provides a titanium-based composite material and a method for preparing the foil thereon, which solves at least one of the problems of high preparation cost, long cycle, poor comprehensive performance and difficulty in making ultrathin foil in existing titanium-based composite materials with high reinforcing phase content.
[0006] On one hand, the present invention provides a method for preparing a titanium-based composite material, comprising the following steps: (1) The titanium powder and the reinforcing phase particles were ball-milled and mixed; (2) The powder mixed in step (1) is cold isostatically pressed to obtain a powder blank; (3) Vacuum sintering is performed on the powder ingot obtained in step (2); (4) The blank after vacuum sintering in step (3) is subjected to hot isostatic pressing; (5) The billet after hot isostatic pressing in step (4) is forged and rolled to obtain titanium-based composite material plates.
[0007] Specifically, in step (1), the average particle size of the titanium powder is not greater than 30 μm, and the average particle size of the reinforcing phase particles is not greater than 15 μm; And / or, the reinforcing phase particles are one or more combinations of TiC, TiB, TiN, B4C, and TiB2.
[0008] Preferably, the titanium powder is pure titanium powder, and the purity of the reinforcing phase particles is ≥99.5%.
[0009] The aforementioned ceramic reinforcing phase has high hardness and high modulus, which can effectively bear loads and is conducive to achieving high modulus and high strength in composite materials.
[0010] Preferably, in step (5), the volume fraction of titanium in the titanium-based composite material plate is 75%~90%, and the volume fraction of the reinforcing phase is 10%~25%.
[0011] Preferably, the volume fraction of the reinforcing phase in the titanium-based composite material plate is 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, or 25%.
[0012] By controlling the volume fraction of the reinforcing phase in the titanium-based composite sheet to 10%~25%, a balance between the high modulus properties and processability of the material is achieved. This ensures that the composite material obtains significantly higher elastic modulus and strength than traditional titanium alloys, while still having the necessary plastic deformation capacity, providing a material basis for subsequent rolling into foil.
[0013] For example, in step (1), the titanium powder and reinforcing phase particles are ball-milled in an argon atmosphere for 10-30 hours. The ball milling speed is 150-250 r / min, and the ball-to-particle ratio is 1:1-5:1. Ball milling in an argon atmosphere can prevent the oxidation of titanium powder.
[0014] Preferably, the ball-to-material ratio is 1:1, 1:2, 1:3, 1:4, or 1:5.
[0015] Further, in step (2), the pressure of the cold isostatic pressing is 150MPa~300MPa, and the holding time is 1.0h~3.0h. Preferably, the pressure of the cold isostatic pressing is 150MPa, 200MPa, 250MPa, or 300MPa.
[0016] It is worth noting that in step (2), the mixed powder is placed into a rubber sleeve and then subjected to cold isostatic pressing.
[0017] Preferably, the vacuum sintering temperature in step (3) is 900℃~1200℃, the holding time is 2.0h~6.0h, and the vacuum degree is 1.0×10⁻⁶. -2 Pa ~ 1.0 × 10 -3 Pa.
[0018] Preferably, the vacuum sintering temperature is 900℃, 950℃, 1000℃, 1050℃, 1100℃, 1150℃, or 1200℃.
[0019] It is worth noting that the hot isostatic pressing in step (4) does not require the use of a metal sheath, the pressure is 120MPa~200MPa, the heating temperature is 800℃~1100℃, and the holding time is 1.0h~5.0h.
[0020] Preferably, the pressure of the hot isostatic pressing is 120MPa, 150MPa, 180MPa, or 200MPa; and the temperature of the hot isostatic pressing is 800℃, 850℃, 900℃, 950℃, 1000℃, 1050℃, or 1100℃.
[0021] It should be noted that the vacuum sintering in step (3) has already initially densified the billet, forming a solid that can withstand subsequent processes. Therefore, the hot isostatic pressing step can effectively eliminate internal porosity without the need for a metal sheath, resulting in a high-density billet. This invention controls the vacuum sintering temperature in a relatively low range of 900℃~1200℃, which is sufficient to achieve metallurgical bonding between powder particles and initial densification of the billet, giving the billet a certain strength and airtightness. However, it avoids excessive grain growth and intensified interfacial reactions caused by excessively high temperatures, providing a safe microstructure basis for subsequent hot isostatic pressing without metal sheath protection.
[0022] Furthermore, in step (5), the forging process controls the deformation in the thickness direction to be ≥30%, and the rolling process has 2 to 5 rolling passes, with a total deformation of not less than 50%.
[0023] The large deformation of no less than 30% in the forging stage can effectively break the original coarse grains and cast structure formed during sintering and hot isostatic pressing, improve the plastic processing capability of the billet, and provide a raw billet with uniform structure and qualified size for subsequent rolling. This solves the problem of easy cracking and uneven deformation when directly rolling excessively thick billets. The total deformation of no less than 50% in the rolling stage can further refine the grains, densify the structure, and promote a more uniform rheological distribution of the reinforcing phase particles, thereby significantly improving the matching degree of strength, plasticity and toughness of the obtained plate, while improving isotropy.
[0024] Specifically, in step (5), the heating temperature of the forging process is 900℃~1200℃ and the holding time is 2.0h~4.0h; the heating temperature of the rolling process is 900℃~1200℃ and the holding time is 1.0h~3.0h.
[0025] Preferably, the heating temperature during the forging process is 900℃, 950℃, 1000℃, 1050℃, 1100℃, 1150℃, or 1200℃; and the heating temperature during the rolling process is 900℃, 950℃, 1000℃, 1050℃, 1100℃, 1150℃, or 1200℃.
[0026] On the other hand, the present invention also provides a method for preparing titanium-based composite foil, which uses titanium-based composite sheet with a reinforcing phase volume fraction of 10% to 25% as raw material and includes the following steps: S1. The titanium-based composite material plate is processed into a sheet, and the sheet is subjected to surface finishing and vacuum annealing. S2. The sheet obtained in S1 is welded and clad to obtain a stacked roll, which is then hot rolled and vacuum annealed to obtain an intermediate sheet. S3. The intermediate sheet obtained in S2 is thinned and surface-treated by grinding and polishing, and then vacuum annealed to obtain a titanium-based composite foil with a thickness of no more than 0.2 mm.
[0027] Preferably, in step S1, the titanium-based composite material sheet is processed into a sheet by mechanical cutting or wire cutting to fully eliminate the internal stress of the sheet; the surface is finished by sanding or precision milling to remove the surface oxide layer from the cutting process, and the surface roughness of the finished sheet is controlled to be ≤3.2μm, which can effectively remove surface defects such as microcracks and scratches generated during mechanical processing and avoid cracking in the subsequent rolling process.
[0028] For example, in S1, the vacuum annealing temperature is 500℃~800℃, the holding time is 1.0h~4.0h, and the vacuum degree is 1.0×10⁻⁶. -2 Pa ~ 1.0 × 10 -3 Pa, the cooling method after annealing is furnace cooling.
[0029] Furthermore, in S2, the number of hot rolling passes is 3 to 5, and the total hot rolling deformation is controlled to be ≥65%.
[0030] In one possible implementation, the hot rolling process in S2 is carried out as follows: the sheets obtained in S1 are welded together in groups of 3 to 5 sheets and then covered with steel plates to obtain a lap-rolled ladle. The thickness of the steel plate in the lap-rolled ladle is 1.0 mm to 10.0 mm. Lubricant is applied to the surface of the titanium-based composite material sheets and one side of the steel plate. The hot rolling heating temperature is 800℃ to 1000℃, the holding time is 0.5 h to 3.0 h, the number of rolling passes is 3 to 5, and the total deformation is not less than 65%. During the hot rolling process, when the surface temperature of the material is lower than 850℃, it needs to be returned to the furnace to be heated to 800℃ to 1000℃ before continuing rolling. The vacuum annealing temperature is 500℃ to 800℃, the holding time is 0.5 h to 3.0 h, and the vacuum degree is 1.0 × 10⁻⁶. -2 Pa ~ 1.0 × 10 -3 Pa, the cooling method is furnace-in-flight cooling.
[0031] Preferably, in S3, the intermediate sheet is cut to a predetermined size to facilitate subsequent grinding operations before grinding and polishing.
[0032] Furthermore, in the grinding process described in S3, the grinding particles used are one or more combinations of diamond, silicon carbide, alumina, and boron nitride. The particle size of the grinding particles is 500-2000 mesh, which can ensure high material removal efficiency while avoiding the introduction of an excessively deep surface damage layer. A flat polishing machine is used to polish the ground sheet, and the polishing consumable is a polishing wheel containing silicon carbide particles with a mesh size of 500-1500 mesh. This effectively eliminates grinding marks and obtains a uniform and delicate surface effect. The combined grinding and polishing process ensures that the prepared foil not only has precise and uniform thickness but also excellent surface quality, fully meeting the stringent requirements for foil surface condition in fields such as precision electronic devices. The vacuum annealing temperature is 500℃-800℃, the holding time is 0.5h-3.0h, and the vacuum degree is 1.0×10⁻⁶. -2 Pa ~ 1.0 × 10 -3 Pa, cooled with the furnace.
[0033] On the other hand, the present invention also provides a titanium-based composite foil, which is prepared by the method of preparing the titanium-based composite foil, wherein the thickness of the titanium-based composite foil is not greater than 0.2 mm.
[0034] Compared with the prior art, the present invention has at least the following beneficial effects: 1. This invention solves the problem of incomplete densification of titanium-based composite materials due to the high volume fraction (10%~25%) of reinforcing phase in conventional sintering by employing a synergistic process of low-temperature vacuum sintering followed by hot isostatic pressing (HIP). Specifically, the ingot is first initially densified through vacuum sintering, followed by HIP without the need for an external metal sheath. HIP effectively eliminates the porosity remaining inside the composite material after vacuum sintering, achieving complete densification, and further improves material properties through forging and rolling plastic deformation. Furthermore, the HIP process of this invention does not require a sheath, which eliminates the risk of iron-titanium eutectic reaction and the formation of brittle intermetallic compounds at high temperatures caused by the use of stainless steel sheaths in traditional processes. It also eliminates the need for a lengthy vacuum degassing process for the metal sheath, significantly shortening the preparation cycle and reducing costs.
[0035] 2. This invention solves the technical challenge of rolling high-volume-fraction reinforced titanium-based composite materials into ultra-thin foils due to their poor plasticity and susceptibility to oxidation by employing a composite process of mechanical cutting for thinning, hot rolling with coating, grinding, and polishing. First, initial thinning is achieved through mechanical cutting or wire cutting, effectively avoiding the cracking risk of highly brittle materials under traditional large-deformation cold rolling. Then, hot rolling is performed after welding and coating to further thin the material. Grinding and polishing processes precisely control the final dimensions and thoroughly remove surface defects and oxide layers generated in the previous processing, resulting in a uniform and clean surface. Finally, vacuum annealing further eliminates processing stress, improving the flatness and dimensional stability of the foil. Through the synergistic effect of these multiple processes, high-modulus titanium-based composite foils with a thickness of 0.1mm~0.2mm, smooth surface, good flatness, and excellent overall performance are produced.
[0036] 3. The thickness of the titanium-based composite material foil of the present invention is 0.1mm~0.2mm, and the surface roughness Ra is ≤0.20μm. Attached Figure Description
[0037] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a SEM image of the titanium-based composite material in Example 1 of the present invention; Figure 2 This is a SEM image of the titanium-based composite material in Example 2 of the present invention; Figure 3 This is an appearance diagram of the titanium-based composite foil used in Example 1 of the present invention; Figure 4 This is a schematic diagram of the thickness test of titanium-based composite foil, which is an application example of the present invention.
[0038] Figure label: 1-Titanium boride particles; 2-Titanium carbide particles. Detailed Implementation
[0039] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.
[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.
[0041] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0042] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0043] Existing titanium-based composite materials and foils are insufficient to meet the urgent needs of aerospace and other fields for ultrathin, high-strength, and high-modulus foils. As the content of reinforcing phases increases to achieve high modulus, the material's processing plasticity deteriorates sharply, leading to cracking during traditional cold rolling, while hot rolling easily causes surface oxidation and dimensional instability. Current technologies typically focus on optimizing single process parameters, but struggle to achieve stable fabrication of ultrathin foils while maintaining high modulus. This invention firstly utilizes a synergistic process of low-temperature vacuum sintering and uncoated hot isostatic pressing to prepare high-density, high-performance bulk composite materials at low cost. Furthermore, for the prepared brittle material, a composite process of mechanical cutting for thinning—coating hot rolling—grinding—polishing is employed to replace the traditional direct rolling path, solving the problem of preparing high-modulus titanium-based composite ultrathin foils.
[0044] The preparation method of the titanium-based composite material and its foil of the present invention will be described below with reference to specific embodiments.
[0045] Example 1 This embodiment provides a high-modulus titanium-based composite material sheet and its preparation method.
[0046] Raw materials: 97.0 wt% pure titanium powder and 3.0 wt% B4C particles; the titanium powder is pure titanium powder with an average particle size of no more than 30 μm; the purity of the reinforcing phase particles B4C is ≥99.5% and the average particle size is no more than 15 μm.
[0047] The target composition of the composite material plate is (12.7%TiB+3.0%TiC) / TA1, with TA1 titanium powder as the matrix, and TiB and TiC are generated by the in-situ reaction of reinforcing phase particles B4C with titanium as reinforcing phases. The volume fraction of titanium is 84.3%, and the volume fraction of reinforcing phases TiB and TiC is 15.7%.
[0048] The preparation method of titanium-based composite materials is as follows: (1) Pure titanium powder and reinforcing phase particles are ball-milled in an argon atmosphere at a predetermined ratio for 20 hours. The ball milling speed is 150 r / min and the ball-to-material ratio is 2:1.
[0049] (2) The powder mixed in step (1) is subjected to cold isostatic pressing. The pressure of cold isostatic pressing of the powder is 200 MPa and the holding time is 1.5 h to obtain powder blank. (3) The powder ingot obtained in step (2) is vacuum sintered in a vacuum sintering furnace at a temperature of 900~1200℃ for 3.0h, with a vacuum degree of less than 1.0×10⁻⁶. -2 Pa; The material achieves preliminary densification after vacuum sintering; (4) Under the condition of no metal cladding, the blank after vacuum sintering in step (3) is subjected to hot isostatic pressing to eliminate the pores inside the material and achieve complete densification of the powder. The hot isostatic pressing pressure is 150 MPa, the heating temperature is 800~1100℃, the holding time is 3.0 h, and the protective atmosphere is argon. (5) The billet after hot isostatic pressing in step (4) is forged. The heating temperature is 900~1200℃ and the holding time is 2.0h. The forging is carried out on a forging machine. The thickness deformation is 30%. The thickness of the billet after forging is 42mm. Then the next rolling process is carried out. The heating temperature is 900~1200℃ and the holding time is 2.0h. The number of rolling passes is 3. The total thickness deformation is 50%. The thickness of the billet after rolling is 21mm. Titanium-based composite material plate is obtained.
[0050] The density of the composite material sheet prepared by the above method was found to be 4.52 g / cm³. 3 The material has an elastic modulus of 150 GPa, a room temperature tensile strength of 880 MPa, a yield strength of 823 MPa, and an elongation of 6.0%. The SEM morphology of the composite material in this embodiment is shown below. Figure 1 As shown.
[0051] The density test method refers to GB / T 1423, the elastic modulus test method refers to GB / T 22315, and the tensile strength, yield strength and elongation test refers to GB / T 228.1.
[0052] Example 2 This embodiment provides a high-modulus titanium-based composite material sheet and its preparation method.
[0053] Raw materials: 85.5 wt% pure titanium powder, 5.5 wt% TiC particles, and 9.0 wt% TiB2 particles; the titanium powder is pure titanium powder with an average particle size of no more than 30 μm; the purity of the reinforcing phase particles is ≥99.5%, the average particle size of TiC is no more than 15 μm, and the average particle size of TiB2 is 1~15 μm.
[0054] The target composition of the composite material plate is (15%TiB2+5%TiC) / TA1, with TA1 titanium powder as the matrix and TiB2 and TiC as the reinforcing phases, wherein the volume fraction of titanium is 80% and the volume fraction of the reinforcing phases TiB2 and TiC is 20%.
[0055] The preparation method of titanium-based composite materials is as follows: (1) Pure titanium powder and reinforcing phase particles are ball-milled in an argon atmosphere at a predetermined ratio for 15 hours. The ball milling speed is 180 r / min and the ball-to-material ratio is 1.5:1.
[0056] (2) The powder mixed in step (1) is subjected to cold isostatic pressing. The pressure of cold isostatic pressing of the powder is 230 MPa and the holding time is 2 h to obtain the powder blank. (3) The powder ingot obtained in step (2) is vacuum sintered in a vacuum sintering furnace at a temperature of 900~1200℃ for 3.0h, with a vacuum degree of less than 1.0×10⁻⁶. -2 Pa; The material achieves preliminary densification after vacuum sintering; (4) Under the condition of no metal cladding, the blank after vacuum sintering in step (3) is subjected to hot isostatic pressing to eliminate the pores inside the material and achieve complete densification of the powder. The hot isostatic pressing pressure is 150 MPa, the heating temperature is 800~1100℃, the holding time is 3.0 h, and the protective atmosphere is argon. (5) The billet after hot isostatic pressing in step (4) is forged. The heating temperature is 900~1200℃ and the holding time is 2.0h. The forging is carried out on a forging machine. The thickness deformation is 35%. The thickness of the billet after forging is 45.5mm. Then the next rolling process is carried out. The heating temperature is 900~1200℃ and the holding time is 2.0h. The number of rolling passes is 4. The total thickness deformation is 60%. The thickness of the billet after rolling is 18.2mm. Titanium-based composite material plate is obtained.
[0057] The density of the composite material sheet prepared by the above method was found to be 4.53 g / cm³. 3The material has an elastic modulus of 159 GPa, a room temperature tensile strength of 1074 MPa, a yield strength of 1028 MPa, and an elongation of 3.0%. The SEM morphology of the composite material in this embodiment is shown below. Figure 2 As shown.
[0058] The density test method refers to GB / T 1423, the elastic modulus test method refers to GB / T 22315, and the tensile strength, yield strength and elongation test refers to GB / T 228.1.
[0059] Application Example 1 This application example provides a method for preparing foil using the (12.7%TiB+3.0%TiC) / TA1 titanium-based composite material from Example 1 as the raw material.
[0060] The specific preparation process is as follows: S1. The titanium-based composite material sheet is mechanically cut into 1.0mm thick sheets. After precision milling, it is vacuum annealed at a temperature of 500~800℃ for 2.0h, with a vacuum degree ≤1.0×10⁻⁶. -2 Pa, the cooling method is furnace cooling, which fully eliminates the internal stress of the slab; S2. The sheets obtained in S1 are welded in groups of five. After welding, the surface is covered with a steel plate to prepare a lap-rolled ladle. The steel plate thickness in the lap-rolled ladle is 5.0 mm. Lubricant is applied to the surface of the titanium-based composite slab and one side of the steel plate. The rolling heating temperature is 900℃, the holding time is 1.0 h, the number of rolling passes is 3, and the total deformation is 70%. If the material surface temperature is lower than 800℃, it needs to be reheated in the furnace to 800~1000℃ before continuing rolling. The rolled sheets are then subjected to metallographic vacuum annealing at 800℃ for 1.0 h, with a vacuum degree ≤1.0×10⁻⁶. -2 Pa, the cooling method is furnace cooling, and an intermediate thin sheet of 0.25±0.05mm is obtained; S3. The intermediate sheet obtained in S2 is thinned and surface-treated by grinding and polishing, followed by vacuum annealing to obtain a titanium-based composite foil with a thickness not exceeding 0.2 mm. The intermediate sheet is cut into 140*70 mm specifications and placed in a grinding machine for surface grinding. The grinding particles are a combination of diamond and silicon carbide with a particle size of 800 mesh. After grinding, the sheet thickness is 0.16 mm with a thickness tolerance of ±0.015 μm. After grinding, it is polished using a surface polishing machine with a polishing wheel containing silicon carbide particles and a mesh size of 1200. Subsequently, vacuum annealing is performed at a temperature of 800℃ for 1.0 h, with a vacuum degree of ≤1.0×10⁻⁶. -2Pa, cooled in the furnace, finally yielded a product sheet with a surface roughness Ra of 0.5μm and dimensions of 140*70*0.16mm.
[0061] The product appearance in this application example is shown below. Figure 3 The measurement diagram is shown below. Figure 4 .
[0062] Comparative Application Example 1 This comparative application example provides a method for preparing foil using the (12.7%TiB+3.0%TiC) / TA1 titanium-based composite material from Example 1 as the raw material.
[0063] The specific preparation process is as follows: Using a traditional rolling process, the mechanical cutting step in S1 is omitted, and the sheet obtained in Example 1 is directly hot-rolled. The hot rolling process parameters are the same as S2 in Application Example 1 of this invention (heating temperature 900℃, total deformation 70%). However, when the deformation in the first rolling pass reaches approximately 15%, macroscopic cracks appear at the edges of the slab, and these cracks propagate as the rolling continues, eventually leading to the sheet breaking and preventing the acquisition of complete intermediate sheets.
[0064] In summary, this invention solves the problem of long preparation time and high cost of titanium-based composite materials due to high volume fraction (10%~25%) reinforcing phase by adopting a synergistic process of low-temperature vacuum sintering followed by hot isostatic pressing. By employing a composite process of mechanical cutting for thinning, hot rolling with coating, grinding, and polishing, it solves the technical problem of high volume fraction reinforcing phase titanium-based composite materials being difficult to roll into ultra-thin foils due to poor plasticity and easy oxidation. The foil thickness is no more than 0.2 mm, and the surface roughness Ra is ≤0.20 μm.
Claims
1. A method for preparing a titanium-based composite material plate, characterized in that, Includes the following steps: (1) The titanium powder and the reinforcing phase particles were ball-milled and mixed; (2) The powder mixed in step (1) is cold isostatically pressed to obtain a powder blank; (3) Vacuum sintering is performed on the powder ingot obtained in step (2); (4) The blank after vacuum sintering in step (3) is subjected to hot isostatic pressing; (5) The billet after hot isostatic pressing in step (4) is forged and rolled to obtain titanium-based composite material plates.
2. The preparation method according to claim 1, characterized in that, In step (1), the average particle size of the titanium powder is not greater than 30 μm, and the average particle size of the reinforcing phase particles is not greater than 15 μm; And / or, the reinforcing phase particles are one or more combinations of TiC, TiB, TiN, B4C, and TiB2.
3. The preparation method according to claim 1, characterized in that, In step (5), the volume fraction of titanium in the titanium-based composite material plate is 75%~90%, and the volume fraction of the reinforcing phase is 10%~25%.
4. The preparation method according to claim 1, characterized in that, The vacuum sintering temperature in step (3) is 900℃~1200℃, and the vacuum degree is 1.0×10⁻⁶. -2 Pa ~ 1.0 × 10 -3 Pa; And / or, the hot isostatic pressing in step (4) has a temperature of 800℃~1100℃ and a pressure of 120MPa~200MPa.
5. The preparation method according to claim 1, characterized in that, In step (5), the forging process controls the deformation in the thickness direction to be ≥30%; in the rolling process, the number of rolling passes is 2 to 5, and the total deformation is ≥50%.
6. A method for preparing a titanium-based composite foil, characterized in that, Using titanium-based composite material plates with a reinforcing phase volume fraction of 10%~25% as raw materials, the process includes the following steps: S1. The titanium-based composite material plate is processed into a sheet, and the sheet is subjected to surface finishing and vacuum annealing treatment. S2. The sheet obtained in S1 is welded and clad to obtain a stacked roll, which is then hot rolled and vacuum annealed to obtain an intermediate sheet. S3. The intermediate sheet obtained in S2 is thinned and surface-treated by grinding and polishing, and then vacuum annealed to obtain a titanium-based composite foil with a thickness of no more than 0.2 mm.
7. The preparation method according to claim 6, characterized in that, The titanium-based composite material sheet is prepared by the method described in any one of claims 1 to 5.
8. The preparation method according to claim 6, characterized in that, S1 controls the surface roughness of the finished sheet to be ≤3.2μm; And / or, the number of hot rolling passes in S2 is 3 to 5, and the total hot rolling deformation is controlled to be ≥65%.
9. The preparation method according to claim 6, characterized in that, The grinding process described in S3 uses abrasive particles including one or more combinations of diamond, silicon carbide, alumina, and boron nitride, with a particle size of 500-2000 mesh; the polishing process uses a polishing wheel with a mesh size of 500-1500 mesh, and the polishing wheel is made of silicon carbide.
10. A titanium-based composite foil, characterized in that, The titanium-based composite foil is prepared by any one of claims 6 to 9, and the thickness of the foil is not greater than 0.2 mm.