Preparation method of SiC fiber reinforced Ti-based composite ultrathin laminated plate

Abstract

The invention relates to the field of composite material ultrathin laminated plates, in particular to a preparation method of a SiC fiber reinforced Ti-based composite material ultrathin laminated plate. The method comprises the following steps: plating Ti alloy on the surface of SiC fiber by using a physical vapor deposition method; the titanium alloy foil is subjected to acid pickling to remove a surface oxide layer and impurities; the plated fibers are tightly arranged to form a SiCf / Ti alloy plate, the upper surface and the lower surface of the SiCf / Ti alloy plate are bonded to a titanium alloy foil through an adhesive, and a foil-plate-foil prefabricated body is manufactured; sealing the periphery of the prefabricated body, covering gaskets on the upper surface and the lower surface of the prefabricated body, removing the adhesive from the prefabricated body, and placing the prefabricated body in a vacuum hot-pressing mold; and a hot-pressing process is adopted to realize densification composite molding of the laminated plate. According to the method, uniform distribution of SiC fibers is achieved, the mechanical property of the material is effectively improved, the surface flatness is good after the laminated plate is prepared, and the method is suitable for weight reduction application of aerospace structural parts such as skins and reinforcing ribs.

Description

Technical Field

[0001] The invention relates to the field of ultra-thin composite laminates, in particular to a method for preparing an ultra-thin SiC fiber reinforced Ti-based composite laminate. Background Art

[0002] With the development of aerospace technology, the surface temperature of aircraft is getting higher and higher, which puts higher and higher requirements on the skin structural materials of ultra-high-speed aircraft. SiC fiber reinforced Ti-based composite materials with high specific strength, high specific modulus and high operating temperature are expected to be used as new skin materials for ultra-high-speed aircraft, that is, ultra-thin large surface area structural parts. Unlike traditional ultra-thin alloy plates, the thickness of SiC fiber itself reaches 0.1mm. The ultra-thin laminates mentioned here refer to SiC fiber reinforced Ti-based composite materials with a thickness of less than 0.5mm. Traditional SiC fiber reinforced Ti-based composites are generally used as structural materials with a larger thickness such as blade rings, disks and rods. At present, the preparation of ultra-thin laminates of SiC fiber reinforced Ti-based composites is a key issue that needs to be solved.

[0003] SiC fiber reinforced Ti-based composite materials are usually prepared by hot isostatic pressing or hot pressing. The advantages of hot isostatic pressing are uniform pressure, dense structure and good formability during the preparation process. However, it is not suitable for ultra-thin laminates of SiC fiber reinforced Ti-based composite materials because the fibers are difficult to fix. And because the thickness of the laminate is too low, its sheath preparation is difficult and the flatness is difficult to ensure. Compared with the hot isostatic pressing process, the hot pressing process is suitable for the preparation of laminates. The traditional hot pressing method is to prepare laminates by stacking foil-fiber-foil. The laminates have better flatness, but there are also problems such as difficulty in fixing the fibers and the hot pressing process easily causing uneven fiber distribution, which limits the practical application of composite laminates.

[0004] Patent publication number CN102277544A proposes a strength-designable and weldable SiCf / Ti-based composite 0 / 90° laminate and its preparation method. This primarily addresses the strength designability of SiC / Ti-based composite 0 / 90° laminates, achieved through adjustment of the layup pattern and fiber volume fraction. However, it fails to address the issues of fiber displacement suppression and low warpage control in ultra-thin laminates (thickness ≤ 0.5 mm). Patent publication number CN108048762A proposes a method for preparing SiC fiber-reinforced titanium-based composite sheets. This method utilizes physical vapor deposition (PVD) to prepare precursor filaments and spark plasma sintering (SPS). This method results in a rapid heating rate, which can easily lead to thermal stress concentration and warping in ultra-thin sheets. Patent publication number CN1532301A proposes a method for preparing continuous SiC fiber-reinforced Ti alloy-based composite materials. The prefabricated tape is prepared using Ti alloy powder and polystyrene binder. The powder metallurgy method is used. The matrix density is low and cannot meet the structural strength requirements of ultra-thin laminates (≤0.5mm). When preparing ultra-thin laminates, it is difficult to ensure the precise fixation of the fibers and the flatness of the laminates.

[0005] For ultra-thin composite laminates, designing a preparation process to obtain high-performance ultra-thin composite laminates and realizing the application of ultra-thin composite laminates are issues that need to be solved urgently. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for preparing an ultra-thin SiC fiber reinforced Ti-based composite laminate, so as to solve the problem of uneven fiber distribution and tissue defects in the preparation process of the ultra-thin composite laminate, which leads to reduced performance of the composite material.

[0007] The technical solution of the present invention is:

[0008] A method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite materials comprises the following steps:

[0009] (1) Ti alloy was plated onto the surface of SiC fiber by physical vapor deposition method, and the volume fraction of SiC fiber was controlled between 20% and 70%;

[0010] (2) removing the surface oxide layer and impurities from the titanium alloy foil by pickling;

[0011] (3) Arrange the plated fibers tightly into SiC f / Ti alloy plate, and SiC f The upper and lower surfaces of the Ti alloy plate are bonded to the titanium alloy foil respectively. The surrounding area of ​​the titanium alloy foil is thicker than that of the SiC f / Ti alloy plates with a width of 4 to 6 mm are made into foil-plate-foil preforms;

[0012] (4) Seal the preform around the periphery and cover the upper and lower surfaces of the preform with gaskets, remove the adhesive from the preform and place it in a vacuum hot pressing mold;

[0013] (5) Using hot pressing process to achieve densification and composite molding of laminates;

[0014] (6) Remove the reaction layer on the surface of the preform and the surrounding excess parts.

[0015] The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate comprises a single-layer arrangement of SiC fibers, a Ti alloy matrix between the SiC fibers, an overall laminate thickness of less than 0.3 mm, and a laminate warpage of less than 1%.

[0016] The method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite materials comprises the following steps: in step (1), the power of the physical vapor deposition equipment is 500 to 5000 W, the time is 6 to 24 hours, and the coating thickness is 10 to 60 μm.

[0017] The method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite materials comprises the following steps: in step (2), the thickness of the Ti alloy foil is less than 100 μm, the pickling solution comprises the following components: 420 to 500 mL / L of nitric acid, 40 to 90 mL / L of hydrofluoric acid, 1 g / L of sodium lauryl sulfate, and the balance water; the pickling time is 10 to 20 minutes, and the surface is rinsed with high-purity alcohol after pickling.

[0018] The method for preparing a SiC fiber reinforced Ti-based composite material ultra-thin laminate, in step (3), the plated fibers are tightly arranged into SiC by a CNC winding machine. f / Ti alloy plate, fixed by adhesive tape; polymethyl methacrylate and acetone are uniformly mixed at 70-90°C as an adhesive, the content of polymethyl methacrylate in the adhesive is 40-60g / L, the adhesive is sprayed on the surface of the titanium alloy foil, and the SiC f / Ti alloy plate is bonded to titanium alloy foil.

[0019] The method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite materials, in step (4), the preform is fixed around by spot welding, 5 points are punched on each side, the spacing between each point is 1 to 2 cm, and the gasket thickness is 1 to 3 mm.

[0020] The method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite material comprises the following steps: in step (4), placing the preform into a vacuum heat treatment furnace to remove the adhesive at a temperature of 300-400°C for 1-3 hours; and installing a graphite plate on the hot pressing head and the bottom of the vacuum hot pressing mold, wherein the graphite plate has a thickness of 100-200 mm to ensure that the laminate is evenly stressed.

[0021] In step (5) of the preparation method of the SiC fiber reinforced Ti-based composite ultra-thin laminated plate, the vacuum is extracted to -0.1 MPa before hot pressing, then argon is introduced to open the mechanical pump for furnace washing, the time is 10-15 s, and then the molecular pump is used to extract the pressure in the vacuum hot pressing mold to 1*10 -3 MPa.

[0022] In step (5) of the preparation method of the SiC fiber reinforced Ti-based composite ultra-thin laminated plate, the hot pressing process parameters are as follows: the preform is heated in a radiation heating mode, the holding temperature is 950-1000 DEG C, the heating speed is 2-30 DEG C / min, the pressure is applied after reaching the holding temperature, the pressure is 30-40 MPa, the pressure speed is 0.5-5 MPa / min, the holding time is 2-5 h after reaching the specified pressure, and the laminated plate is cooled to room temperature with the furnace after the composite forming holding is finished.

[0023] In step (6) of the preparation method of the SiC fiber reinforced Ti-based composite ultra-thin laminated plate, the excess part around is removed by diamond wire cutting, the reaction layer between the gasket and the laminated plate is removed by electric grinding machine and diamond abrasive, the diamond abrasive is selected from W10 to W60, and the plate is polished from high to low step by step to avoid warping.

[0024] The design idea of the application is:

[0025] In the prior art, the preparation of the SiC fiber reinforced Ti-based composite ultra-thin laminated plate has problems of uneven fiber distribution, serious warping and difficult to guarantee flatness, which limits its application in the field of aerospace. The application effectively solves the problems of fiber fixation, laminated plate flatness and warping control through Ti alloy layer plating on the surface of SiC fiber, using polymethyl methacrylate (PMMA) as an adhesive, spot welding fixation and graphite pad, and realizes high-performance preparation of the ultra-thin laminated plate.

[0026] The application realizes precise preparation of the ultra-thin laminated plate through the synergistic process of SiC fiber surface coating modification, preform constraint fixation and hot pressing densification:

[0027] (1) SiC fiber surface coating modification: 10-60 mu m Ti alloy layer is plated on the surface of SiC fiber by PVD, the coating thickness of 10-60 mu m can ensure that the Ti alloy uniformly covers the surface of SiC fiber, forms good interface bonding, controls the interface bonding strength and avoids the generation of brittle phase; in addition, the volume fraction of SiC fiber is controlled between 20% and 70%, and by adjusting the fiber volume fraction between 20% and 70%, the performance of the composite material can be optimized according to different application requirements.

[0028] (2) Preform constraint and fixation: The CNC winding machine precisely arranges the fibers, combined with tape bonding, spot welding fixation and pickling Ti foil activation to prevent fiber slippage.

[0029] (3) Hot pressing densification: Stepwise pressurization is performed at 0.5-5 MPa / min to 30-40 MPa to achieve uniform pressurization and avoid fiber damage, thereby ensuring the uniformity, densification, and optimization of mechanical properties of the SiC fiber reinforced Ti-based composite ultra-thin laminate during the preparation process. In combination with the graphite plate and vacuum environment, both densification and flatness are taken into account.

[0030] The present invention has the following advantages and beneficial effects:

[0031] 1. The present invention realizes the preparation of ultra-thin SiC fiber reinforced Ti-based composite laminates for the first time. The minimum thickness of the laminate can reach 0.28 mm, and the warping degree of the fiber reinforced composite laminate is relatively small.

[0032] 2. The ultra-thin composite laminate prepared by the present invention has a good matrix and fiber filling effect and the fibers are evenly dispersed, which overcomes the problem of uneven fiber distribution in the hot pressing process leading to reduced mechanical properties of the material.

[0033] 3. The composite laminate prepared by the present invention has excellent mechanical properties, which broadens the application range of the original SiC fiber reinforced Ti-based composite material.

[0034] 4. The present invention is applicable to most Ti alloy substrates, such as high-temperature titanium alloys (i.e., Ti60 / Ti65), intermetallic compounds (Ti2AlNb, TiAl), and common Ti alloys (TC4, TC17, etc.). Different substrate alloys can be replaced according to different environmental requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 (a) A macroscopic image and (b) a cross-sectional scanning electron microscope image of the laminate prepared in Example 1 of the present invention.

[0036] Figure 2 This is the deflection-strength curve of the laminate prepared in Example 1 of the present invention.

[0037] Figure 3 (a) A macroscopic image and (b) a scanning electron microscope image of a cross section of the laminate prepared in Example 2 of the present invention. DETAILED DESCRIPTION

[0038] In the specific implementation process, the present invention proposes a method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite materials, the preparation method includes plating a Ti alloy matrix on the surface of SiC fiber, designing the arrangement and bonding method to impose external constraints on the fiber, so that the plated fiber is initially connected to the titanium alloy foil, and designing a hot pressing process to remove the adhesive and densification process. First, the Ti alloy is plated on the surface of the SiC fiber by physical vapor deposition, and the volume fraction of the SiC fiber is controlled between 20% and 70%, which can regulate the volume fraction of the matrix and fiber in the laminate; secondly, the oxide layer and impurities on the surface of the titanium alloy foil are removed by pickling to prepare for obtaining a laminate with dense structure and no defects; then the plated fibers are tightly arranged to form a SiC f / Ti alloy plate, and SiC f The upper and lower surfaces of the SiC / Ti alloy plate are respectively bonded to the titanium alloy foil to form a foil-plate-foil preform. Then, the preform is sealed on all sides to ensure that the relative position of the fibers remains unchanged during the subsequent preparation process. Gaskets are covered on the upper and lower surfaces of the preform to prevent the laminate from reacting with the mold. After removing the adhesive from the preform, it is placed in a vacuum hot pressing mold. Finally, a hot pressing process is used to achieve densification and composite molding of the laminate, and the reaction layer on the surface of the preform and the surrounding excess parts are removed to obtain an ultra-thin SiC fiber-reinforced Ti-based composite laminate with dense structure and high flatness.

[0039] Below, the present invention is further described in detail by examples.

[0040] Example 1

[0041] In this embodiment, a method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite material is provided, and the specific steps are as follows:

[0042] Step 1: Select Ti2AlNb as the matrix and plate Ti2AlNb onto the surface of SiC fiber by physical vapor deposition to form SiC / Ti2AlNb wire. The equipment power is 3500W, the time is 9h, the coating thickness is 20μm, and the volume ratio of fiber to matrix is ​​controlled to be 1:1.

[0043] Step 2: A 100 μm thick Ti65 alloy foil was pickled with a solution consisting of 460 mL / L nitric acid (69 wt%), 50 mL / L hydrofluoric acid (40 wt%), 1 g / L sodium lauryl sulfate, and the balance water. The pickling process lasted 15 minutes, with a thickness of less than 0.3 μm. The oxide layer and impurities on the surface of the Ti65 alloy foil were removed. The foil was then rinsed with high-purity alcohol (99% by volume) to remove the acid.

[0044] Step 3: The obtained SiC / Ti2AlNb wire is tightly arranged into a 100 mm wide and 100 mm long SiC / Ti2AlNb plate using a CNC winding machine and fixed with tape. Polymethyl methacrylate (50 g / L) and acetone are evenly mixed at 80°C as an adhesive, and the upper and lower surfaces of the SiC / Ti2AlNb plate are adhered to the pickled Ti65 alloy foil. The Ti65 alloy foil is 5 mm wider than the SiC / Ti2AlNb plate on all sides to form a foil-plate-foil preform.

[0045] Step 4: Fix the preform around by spot welding, with 5 points on each side and a spacing of 1 to 2 cm between each point, and cover the upper and lower surfaces of the preform with 3 mm thick gaskets; place the preform in a vacuum heat treatment furnace to remove the adhesive, at a temperature of 350 ° C and a time of 2 hours.

[0046] Step 5: Install a graphite plate with a thickness of 100 mm on the hot pressing head and the bottom of the vacuum hot pressing mold. Place the fixed preform into the vacuum hot pressing mold. Evacuate the vacuum hot pressing mold to -0.1 MPa (gauge pressure), then introduce argon gas and turn on the mechanical pump to clean the furnace for 15 seconds. Then use a molecular pump to pump the pressure in the vacuum hot pressing mold to 1×10 -3 MPa.

[0047] Step 6: Heat the preform to 960°C by radiation heating at a heating rate of 5°C / min. After the temperature reaches the set value, pressurize the sample surface to 40MPa at a pressurization rate of 0.5MPa / min. After reaching the specified pressure, keep warm for 2h. After the insulation is completed, cool to room temperature with the furnace to complete the preparation of the composite laminate. The thickness of the SiC fiber reinforced Ti-based composite ultra-thin laminate is 0.28mm.

[0048] Step 7. Remove the excess parts around by diamond wire cutting, and use an electric grinder and diamond abrasives to grind the surface of the laminate to remove the reaction layer between the gasket and the laminate. Select W60, W40 and W20 diamond abrasives, and grind step by step from high to low until the metallic luster is polished to avoid warping of the plate.

[0049] like Figure 1 As shown, the macroscopic image and cross-sectional scanning electron microscope image of the laminate prepared in Example 1 of the present invention. Figure 1 (a) shows that SiC f The warpage of the laminated plate of / Ti2AlNb composite material is small. Figure 1 (b) The scanning electron microscope image shows that the alloy has a dense structure and the SiC fibers are evenly distributed. The dark gray part in the image is the SiC fiber, the white area in the fiber is the W core in the SiC fiber, and the fiber is surrounded by the Ti2AlNb matrix. The light gray part in the image is the Ti65 foil.

[0050] like Figure 2 As shown in the deflection-strength curve of the laminate prepared in Example 1 of the present invention, SiC f The flexural strength of the SiC / Ti2AlNb composite laminate was 2423 MPa, and the deflection corresponding to the flexural strength, which is the deformation of the laminate when the flexural strength is reached, was approximately 1.12 mm. This flexural strength is significantly higher than that of conventional SiC fiber-reinforced Ti-based composite laminates, demonstrating that the SiC fiber-reinforced Ti-based composite ultra-thin laminates prepared by this invention maintain excellent load-bearing capacity despite their ultra-thin structure. This solves the problem of reduced thickness affecting the mechanical properties of ultra-thin laminates, and can meet the demand for high-strength, lightweight structural components in fields such as aerospace.

[0051] Example 2

[0052] In this embodiment, a method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite material is provided, and the specific steps are as follows:

[0053] Step 1: Select TC25G alloy as the matrix, and plate TC25G alloy onto the surface of SiC fiber by physical vapor deposition to form SiC / TC25G precursor wire. The equipment power is 3500W, the time is 9h, the coating thickness is 20μm, and the volume ratio of fiber to matrix is ​​controlled to be 1:1.

[0054] Step 2: A 100 μm thick Ti65 alloy foil was pickled with a solution consisting of 460 mL / L nitric acid (69 wt%), 50 mL / L hydrofluoric acid (40 wt%), 1 g / L sodium lauryl sulfate, and the balance water. The pickling process lasted 15 minutes, with a thickness of less than 0.3 μm. The oxide layer and impurities on the surface of the Ti65 alloy foil were removed. The foil was then rinsed with high-purity alcohol (99% by volume) to remove the acid.

[0055] Step 3: The obtained SiC / TC25G wire is tightly arranged into a 100 mm wide and 100 mm long SiC / TC25G plate using a CNC winding machine and fixed with tape. Polymethyl methacrylate (50 g / L) and acetone are evenly mixed at 80°C as an adhesive, and the upper and lower surfaces of the SiC / TC25G plate are adhered to the pickled Ti65 alloy foil. The Ti65 alloy foil is 5 mm wider than the SiC / TC25G plate on all sides to form a foil-plate-foil preform.

[0056] Step 4: Fix the preform around by spot welding, with 5 points on each side and a spacing of 1 to 2 cm between each point, and cover the upper and lower surfaces of the preform with 3 mm thick gaskets; place the preform in a vacuum heat treatment furnace to remove the adhesive, at a temperature of 350 ° C and a time of 2 hours.

[0057] Step 5: Install a graphite plate with a thickness of 100 mm on the hot pressing head and the bottom of the vacuum hot pressing mold. Place the fixed preform into the vacuum hot pressing mold. Evacuate the vacuum hot pressing mold to -0.1 MPa (gauge pressure), then introduce argon gas and turn on the mechanical pump to clean the furnace for 15 seconds. Then use a molecular pump to pump the pressure in the vacuum hot pressing mold to 1×10 -3 MPa.

[0058] Step 6: Heat the preform to 960°C by radiation heating at a heating rate of 5°C / min. After the temperature reaches the set value, pressurize the sample surface to 40MPa at a pressurization rate of 0.5MPa / min. After reaching the specified pressure, keep warm for 2h. After the insulation is completed, cool to room temperature with the furnace to complete the preparation of the composite laminate. The thickness of the SiC fiber reinforced Ti-based composite ultra-thin laminate is 0.28mm.

[0059] Step 7. Remove the excess parts around by diamond wire cutting, and use an electric grinder and diamond abrasives to grind the surface of the laminate to remove the reaction layer between the gasket and the laminate. Select W60, W40 and W20 diamond abrasives, and grind step by step from high to low until the metallic luster is polished to avoid warping of the plate.

[0060] like Figure 3 As shown, the macroscopic image and cross-sectional scanning electron microscope image of the laminate prepared in Example 2 of the present invention. Figure 1 (a) shows that SiC f / TC25G composite material laminates have less warpage, Figure 1 (b) The scanning electron microscope image shows that the alloy has a dense structure and the SiC fibers are evenly distributed. The dark gray part is the SiC fiber, the white area in the fiber is the W core in the SiC fiber, the light gray part is the Ti65 foil, and the space between Ti65 and the fiber is the TC25G matrix.

[0061] The implementation results show that the composite material of the present invention achieves uniform distribution of SiC fibers, effectively improving the mechanical properties of the material. The surface flatness of the laminated plate is good after preparation, and it is suitable for weight reduction applications in aerospace structural parts such as skins and reinforcements.

Claims

1. A method for preparing an ultra-thin laminate of SiC fiber reinforced Ti-based composite materials, characterized in that: The following steps are involved: (1) Ti alloy was plated onto the surface of SiC fiber by physical vapor deposition method, and the volume fraction of SiC fiber was controlled between 20% and 70%; (2) removing the surface oxide layer and impurities from the titanium alloy foil by pickling; (3) Arrange the plated fibers tightly into SiC f / Ti alloy plate, and SiC f The upper and lower surfaces of the Ti alloy plate are bonded to the titanium alloy foil respectively. The surrounding area of ​​the titanium alloy foil is thicker than that of the SiC f / Ti alloy plates with a width of 4 to 6 mm are made into foil-plate-foil preforms; (4) Seal the preform around the periphery and cover the upper and lower surfaces of the preform with gaskets, remove the adhesive from the preform and place it in a vacuum hot pressing mold; (5) Using hot pressing process to achieve densification and composite molding of laminates; (6) Remove the reaction layer on the surface of the preform and the surrounding excess parts.

2. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: SiC fibers are arranged in a single layer, with a Ti alloy matrix between the SiC fibers. The overall thickness of the laminate is less than 0.3 mm, and the warpage of the laminate is less than 1%.

3. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (1), the power of the physical vapor deposition equipment is 500 to 5000 W, the time is 6 to 24 hours, and the coating thickness is 10 to 60 μm.

4. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (2), the thickness of the Ti alloy foil is less than 100 μm, and the pickling solution composition is: 420-500 mL / L nitric acid, 40-90 mL / L hydrofluoric acid, 1 g / L sodium lauryl sulfate, and the balance water; the pickling time is 10-20 minutes, and the surface is rinsed with high-purity alcohol after pickling.

5. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (3), the plated fibers are tightly arranged into SiC f / Ti alloy plate, fixed by adhesive tape; polymethyl methacrylate and acetone are uniformly mixed at 70-90°C as an adhesive, the content of polymethyl methacrylate in the adhesive is 40-60g / L, the adhesive is sprayed on the surface of the titanium alloy foil, and the SiC f / Ti alloy plate is bonded to titanium alloy foil.

6. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (4), the preform is fixed around by spot welding, with 5 points on each side, the spacing between each point is 1 to 2 cm, and the gasket thickness is 1 to 3 mm.

7. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (4), the preform is placed in a vacuum heat treatment furnace to remove the adhesive at a temperature of 300-400°C for 1-3 hours; a graphite plate with a thickness of 100-200 mm is installed on the hot pressing head and the bottom of the vacuum hot pressing mold to ensure that the laminate is evenly stressed.

8. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (5), the vacuum is pumped to -0.1 MPa before hot pressing, and then argon is introduced and the mechanical pump is turned on to clean the furnace for 10 to 15 seconds. Then the molecular pump is used to pump the pressure in the vacuum hot pressing mold to 1×10 -3 MPa.

9. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (5), the hot pressing process parameters are as follows: the preform is heated by radiation heating, the insulation temperature is 950-1000°C, the heating rate is 2-30°C / min, pressurization is performed after the insulation temperature is reached, the pressure is 30-40 MPa, the pressurization rate is 0.5-5 MPa / min, and insulation is performed for 2-5 hours after the specified pressure is reached. After the composite molding and insulation are completed, the laminate is cooled to room temperature with the furnace.

10. The method for preparing an ultra-thin SiC fiber reinforced Ti-based composite material laminate according to claim 1, characterized in that: In step (6), the excess parts around are removed by diamond wire cutting, and the reaction layer between the gasket and the laminate is removed by grinding the surface of the laminate with an electric grinder and diamond abrasives. The diamond abrasives are selected from W10 to W60 and ground step by step from high to low to avoid warping of the plate.

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