In-situ one-step forming method of carbon fiber reinforced aluminum matrix composite material and titanium material with excellent connecting function

Abstract

The application discloses an in-situ one-step forming method of carbon fiber reinforced aluminum matrix composite material and titanium material with excellent connecting function, and belongs to the field of composite material connection. The purpose is to solve the problems of difficult control of interface reaction, difficult connection of composite material and difficult guarantee of material performance after connection in the existing carbon fiber reinforced aluminum matrix composite material. The application realizes the precise regulation and control of the interface reaction kinetics process through the preparation of the preform, the precise embedding of the titanium material, the preheating of the mold, the smelting of the aluminum liquid and the integrated forming process of pressure infiltration, solves the problem of double interface reaction, effectively inhibits the excessive precipitation of brittle phases such as Al4C3 and TiAl3, is beneficial to the subsequent welding processing of the composite material, avoids the welding thermal damage, guarantees the strength of the joint, simultaneously simplifies the preparation process and reduces the production cost. The prepared component is complete in structure, dense in interface combination, excellent in mechanical properties, good in joint anti-debonding performance and suitable for the high-end lightweight bearing structural component in the field of aviation and aerospace, and has a good engineering application prospect.

Description

Technical Field

[0001] This invention relates to a method for joining aluminum-based composite materials and titanium materials, belonging to the field of composite material joining. Background Technology

[0002] Aluminum-based composites possess significant advantages in lightweight structure manufacturing due to their low density, high thermal conductivity, excellent dimensional stability, and mechanical designability. Compared to traditional single aluminum alloys, carbon fiber reinforced aluminum-based composites further combine the outstanding characteristics of carbon fiber—high specific strength, high specific modulus, and low coefficient of thermal expansion—effectively compensating for the shortcomings of traditional aluminum alloys, such as low modulus, poor high-temperature stiffness, and susceptibility to deformation. These composites combine the toughness and electrical and thermal conductivity of a metal matrix with the high strength and lightweight advantages of carbon fiber. They maintain structural stability under high temperatures, alternating loads, and high-precision operating conditions and are now widely used in core areas such as aerospace structural components, high-end equipment load-bearing components, and precision engineering structures, representing a key development direction for advanced lightweight metal-based composite materials.

[0003] However, existing carbon fiber reinforced aluminum matrix composites still face two major technological bottlenecks in engineering applications, severely restricting their large-scale promotion and application. The first is the poor compatibility and stability of the carbon-aluminum interface. During the high-temperature preparation and service of the composite material, the carbon fiber and aluminum matrix are prone to violent interfacial reactions, generating brittle carbon-aluminum compounds, causing interfacial deterioration. This easily leads to interfacial debonding, microcrack initiation and propagation, significantly reducing the overall mechanical properties and service reliability of the composite material. The second is the challenge of composite material joining. Carbon fiber reinforced aluminum matrix composites are difficult-to-weld special metal matrix composites, and traditional joining processes such as fusion welding, brazing, and diffusion welding all have significant defects. Conventional welding heat input causes the aluminum matrix to melt, carbon fiber to ablate and fracture, and a large amount of brittle phase to precipitate at the interface, completely destroying the original microstructure and mechanical properties of the composite material. Mechanical riveting, bonding, and other auxiliary joining methods suffer from significant stress concentration, low connection strength, poor sealing and fatigue resistance, and cannot meet the high load-bearing, high reliability, and long service life requirements of high-end equipment.

[0004] In addition, existing heterogeneous joining systems of aluminum-based composite materials and titanium alloys also face the technical challenge of uncontrollable aluminum-titanium interface reactions. During high-temperature composite and welding processes, titanium and aluminum readily form high-hardness, low-toughness intermetallic compounds. These brittle phases easily form crack initiation points at the interface, resulting in insufficient interface strength and poor impact resistance. This leads to a significant decrease in the overall reliability of heterogeneous joints, making it difficult to achieve high-strength, high-stability integrated joining.

[0005] In summary, current carbon fiber reinforced aluminum matrix composites generally suffer from severe carbon-aluminum interfacial reactions, poor self-bonding properties, numerous brittle phases at the interface with titanium alloys, and significant deterioration in joint performance. Existing molding and joining processes struggle to balance the material's intrinsic properties with joint strength, and are generally characterized by complexity, high cost, and low yield. Therefore, developing a molding and joining technology that is simple, low-cost, enables in-situ integral molding of composite materials and titanium alloys, effectively suppresses harmful interfacial reactions, and balances both the intrinsic material properties and joint stability, has significant engineering application value and academic research significance. Summary of the Invention

[0006] This invention aims to solve the problems of difficult control of interfacial reaction, difficult bonding of composite materials, and difficulty in guaranteeing the material properties after bonding in existing carbon fiber reinforced aluminum matrix composites, and provides an in-situ one-time molding method for carbon fiber reinforced aluminum matrix composites and titanium materials with excellent bonding function.

[0007] The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function of the present invention is carried out according to the following steps:

[0008] I. Carbon fiber preforming:

[0009] Carbon fibers are processed into the designed shape and their shape is fixed to obtain a carbon fiber preform;

[0010] II. Titanium Material Integration:

[0011] The connecting parts of the titanium material are processed into a shape that can be interlocked with the connecting parts of the carbon fiber preform in step one, and the connecting parts of the titanium material and the connecting parts of the carbon fiber preform are interlocked and connected to obtain a blank. The blank is then placed in an impregnation mold.

[0012] III. Thermal Insulation Treatment:

[0013] The billet and mold obtained in step two are subjected to heat preservation treatment; the temperature of the heat preservation treatment is higher than the solidus line of aluminum material and lower than the liquidus line of aluminum material.

[0014] IV. Preparation of Aluminum Material Melt:

[0015] Aluminum material is smelted to obtain aluminum melt;

[0016] The smelting process is as follows: smelting at 700-950℃ for 2-8 hours;

[0017] V. Pressure Impregnation and Demolding:

[0018] The aluminum material melt is poured into a mold for pressure infiltration, thereby achieving in-situ one-time molding connection between carbon fiber reinforced aluminum matrix composite and titanium alloy;

[0019] The pressure impregnation process is as follows: the pressure applied to the molten aluminum material is 100-290 MPa, and the pressure holding time is 5-20 min.

[0020] The beneficial effects of this invention are:

[0021] 1. The component prepared by the present invention is composed of carbon fiber reinforcing phase, titanium material and titanium material, and is prepared by in-situ one-time molding, which realizes the simultaneous control of aluminum-carbon fiber interface reaction and aluminum-titanium interface reaction, effectively inhibits the excessive growth of brittle intermetallic compounds, thereby significantly improving the bonding strength and toughness of the interface.

[0022] 2. This invention utilizes atmospheric pressure infiltration technology. By controlling the reaction kinetics, a process window was found that simultaneously inhibits two interfacial reactions. The infiltration process is completed at relatively low temperatures and with short pressurization and holding times, solving the problem of brittle intermetallic compounds (Al4C3 and TiAl3) formed by aluminum-carbon fiber and aluminum-titanium interfacial reactions. After infiltration, a metallurgical bond and mechanical interlocking surface structure are formed between the carbon fiber reinforced aluminum matrix composite and the titanium alloy, greatly enhancing the interfacial bonding strength.

[0023] 3. By precisely controlling process parameters, this invention not only simplifies the complexity of traditional multi-step connection processes, but also ensures the structural integrity and reliability of materials under complex stress environments, providing an efficient and stable technical solution for the manufacturing of high-performance lightweight components in aerospace and other fields.

[0024] 4. The integrated molding process of interlocking connection and pressure infiltration adopted in this invention provides a reliable path for connecting complex and stress-sensitive specimens, and the preparation process is simple and low-cost. Existing welding methods result in a molten pool that leads to performance degradation of composite materials, especially since the wettability between aluminum and carbon fiber is poor. After melting and solidification under pressureless conditions, voids and defects are inevitable. This invention allows for free design of the size and structure of Ti alloy connectors, enabling one-time molding of complex components. The titanium material in the component is used for welding during application, and the heat-affected zone of the titanium material is far from the composite material in the component, avoiding damage to the bond between the aluminum matrix and carbon fiber, thus achieving a stable and reliable composite material connection. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of the in-situ one-time forming connection component between carbon fiber reinforced aluminum matrix composite material and titanium material in Example 1;

[0026] Figure 2 The component obtained by welding the titanium materials of the two components in Example 1 together;

[0027] Figure 3This is a microscopic image of the interface between the composite material and the titanium material in the one-piece molded connecting component of Example 1.

[0028] Figure 4 The tensile specimen is a one-piece molded connecting component from Example 1. Detailed Implementation

[0029] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any reasonable combination of the specific embodiments.

[0030] Specific Implementation Method 1: This implementation method, which involves the in-situ one-step molding of carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function, is carried out according to the following steps:

[0031] I. Carbon fiber preforming:

[0032] Carbon fibers are processed into the designed shape and their shape is fixed to obtain a carbon fiber preform;

[0033] II. Titanium Material Integration:

[0034] The connecting parts of the titanium material are processed into a shape that can be interlocked with the connecting parts of the carbon fiber preform in step one, and the connecting parts of the titanium material and the connecting parts of the carbon fiber preform are interlocked and connected to obtain a blank. The blank is then placed in an impregnation mold.

[0035] III. Thermal Insulation Treatment:

[0036] The billet and mold obtained in step two are subjected to heat preservation treatment; the temperature of the heat preservation treatment is higher than the solidus line of aluminum material and lower than the liquidus line of aluminum material.

[0037] IV. Preparation of Aluminum Material Melt:

[0038] Aluminum material is smelted to obtain aluminum melt;

[0039] The smelting process is as follows: smelting at 700-950℃ for 2-8 hours;

[0040] V. Pressure Impregnation and Demolding:

[0041] The aluminum material melt is poured into a mold for pressure infiltration, thereby achieving in-situ one-time molding connection between carbon fiber reinforced aluminum matrix composite and titanium alloy;

[0042] The pressure impregnation process is as follows: the pressure applied to the molten aluminum material is 100-290 MPa, and the pressure holding time is 5-20 min.

[0043] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the carbon fiber mentioned in step one is continuous carbon fiber, and the processing method is winding or weaving.

[0044] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that: the carbon fiber mentioned in step 1 is chopped carbon fiber or a blend of continuous carbon fiber and chopped carbon fiber; the processing method is compression molding.

[0045] Specific Implementation Method Four: This implementation method differs from one of the specific implementation methods one to three in that: the method for fixing the shape described in step one is to use continuous carbon fibers with the same properties for winding and fixing, and the pretension of the continuous carbon fibers during the winding process is 10-20N.

[0046] Specific Implementation Method 5: This implementation method differs from one of the specific implementation methods 1 to 4 in that the elastic modulus of the carbon fiber described in step 1 is higher than 300 GPa.

[0047] Specific Implementation Method Six: This implementation method differs from Specific Implementation Method Three in that the preparation method of the blended fiber is as follows: short-cut carbon fibers are mixed with volatile organic solvents, then ball-milled, and the resulting slurry is then mixed with continuous carbon fibers; the ball-to-material ratio of the ball mill is 10:1, and the ball milling media used is alumina.

[0048] Specific Implementation Method Seven: This implementation method differs from one of the specific implementation methods one to six in that the length of the short-cut carbon fiber in step one is 10-5000μm.

[0049] Specific Implementation Method Eight: This implementation method differs from one of Specific Implementation Methods One to Seven in that: before the carbon fiber described in Step One is processed into the designed shape, it is coated with a silicon carbide sizing agent or an alumina sizing agent.

[0050] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: the titanium material mentioned in step two is pure titanium or a titanium alloy; the titanium alloy is a TA, TB, or TC series titanium alloy.

[0051] Specific Implementation Method 10: This implementation method differs from Specific Implementation Methods 1 to 9 in that: the aluminum material mentioned in step 4 is pure aluminum or aluminum alloy; the aluminum alloy is 1xxx series aluminum alloy, 2xxx series aluminum alloy, 5xxx series aluminum alloy, 6xxx series aluminum alloy or 7xxx series aluminum alloy.

[0052] Specific Implementation Method Eleven: This implementation method differs from Specific Implementation Methods One to Ten in that: the fitting connection is that the connecting part of the titanium material joint is sleeved on the outside of the part to be connected of the carbon fiber preform, the part to be connected of the carbon fiber preform is sleeved on the outside of the connecting part of the titanium material joint, or the titanium material joint and the part to be connected of the carbon fiber preform are connected to each other through a tenon and mortise joint.

[0053] The beneficial effects of the present invention are verified using the following embodiments:

[0054] Example 1:

[0055] The in-situ one-step molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function in this embodiment is carried out according to the following steps:

[0056] I. Carbon fiber preforming:

[0057] Carbon fiber is processed into a round tube with a wall thickness of 2.5 mm and its shape is fixed to obtain a carbon fiber preform.

[0058] The carbon fiber is a continuous carbon fiber, and the processing method is winding; the diameter of the continuous carbon fiber is 3mm, the aspect ratio is 16364, and the model is M40X; the carbon fiber is coated with silicon carbide sizing agent before winding.

[0059] The method for fixing the shape is as follows: continuous carbon fibers with the same properties are wound and fixed, and the pretension of the continuous carbon fibers during the winding process is 20N.

[0060] II. Titanium Material Integration:

[0061] The TC4 titanium alloy is processed into a round tube with an inner diameter of 2.8 mm. The titanium alloy is then fitted onto the end of the carbon fiber preform to obtain a blank. The blank is then placed in an impregnation mold.

[0062] III. Thermal Insulation Treatment:

[0063] The blank and mold obtained in step two are kept at 500℃ for 4 hours.

[0064] IV. Preparation of Aluminum Material Melt:

[0065] The aluminum material melt is obtained by melting 5A06 aluminum alloy; the Mg content in 5A06 aluminum alloy is 6.7%;

[0066] The smelting process is as follows: smelting at 750℃ for 5 hours;

[0067] V. Pressure Impregnation and Demolding:

[0068] The aluminum material melt is poured into a mold for pressure infiltration, thereby achieving in-situ one-time molding connection between carbon fiber reinforced aluminum matrix composite and titanium alloy;

[0069] The pressure impregnation process is as follows: the pressure applied to the molten aluminum material is 150 MPa, and the pressure holding time is 20 min.

[0070] Figure 1 This is a cross-sectional view of the in-situ one-time forming connection component of carbon fiber reinforced aluminum matrix composite material and titanium material in Example 1; in the figure, a is titanium material, which is a thin-walled tube, and b is carbon fiber reinforced aluminum matrix composite material tube, with titanium material sleeved on the carbon fiber reinforced aluminum matrix composite material tube; Figure 2 The component is obtained by welding the two components made of titanium materials together in Example 1; in the figure, a is titanium material and b is carbon fiber reinforced aluminum matrix composite material; Figure 3 This is a microscopic image of the interface between the composite material and the titanium material in the one-piece molded connecting component of Example 1. Figure 3 It can be seen that the interface between Ti and the composite material is clean, and no needle-like or plate-like reactants were found. Figure 4 The tensile specimen is a one-piece molded connecting component in Example 1. After stretching, the carbon fiber reinforced aluminum matrix composite material in the component fractures. The tensile strength of the tensile component reaches 1.1 GPa. At this time, the connection between the titanium material and the composite material at the joint remains intact.

Claims

1. A method for in-situ one-time molding of carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function, characterized in that: The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composites and titanium materials with excellent bonding function is carried out according to the following steps: I. Carbon fiber preforming: Carbon fibers are processed into the designed shape and their shape is fixed to obtain a carbon fiber preform; II. Titanium Material Joint Fitting: The connection part of the titanium material joint is processed into a shape that can be interlocked with the connection part of the carbon fiber preform in step one, and the connection part of the titanium material joint is interlocked with the connection part of the carbon fiber preform to obtain a blank. The blank is placed in an impregnation mold. III. Thermal Insulation Treatment: The blank and mold obtained in step two are subjected to heat preservation treatment; The temperature of the thermal insulation treatment is higher than the solidus line of aluminum and lower than the liquidus line of aluminum. IV. Preparation of Aluminum Material Melt: Aluminum material is smelted to obtain aluminum melt; The smelting process is as follows: smelting at 700-950℃ for 2-8 hours; V. Pressure Impregnation and Demolding: The aluminum material melt is poured into a mold for pressure infiltration, thereby achieving in-situ one-time molding connection between carbon fiber reinforced aluminum matrix composite and titanium alloy; The pressure impregnation process is as follows: the pressure applied to the molten aluminum material is 100-290 MPa, and the pressure holding time is 5-20 min.

2. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The carbon fiber mentioned in step one is continuous carbon fiber, and the processing method is winding or weaving.

3. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The carbon fiber mentioned in step one is chopped carbon fiber or a blend of continuous carbon fiber and chopped carbon fiber; the processing method is compression molding.

4. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The method for fixing the shape described in step one is as follows: continuous carbon fibers with the same properties are wound and fixed, and the pretension of the continuous carbon fibers during the winding process is 10-20N.

5. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The elastic modulus of the carbon fiber described in step one is higher than 300 GPa.

6. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 3, characterized in that: The method for preparing the blended fiber is as follows: short-cut carbon fibers are mixed with a volatile organic solvent, then ball-milled, and the resulting slurry is then mixed with continuous carbon fibers; the ball-to-material ratio of the ball mill is 10:1, and the ball milling media used is alumina.

7. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The length of the short-cut carbon fiber mentioned in step one is 10-5000 μm.

8. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: Before the carbon fiber described in step one is processed into the designed shape, it is coated with silicon carbide sizing agent or alumina sizing agent.

9. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The titanium material mentioned in step two is pure titanium or a titanium alloy; the titanium alloy is a TA, TB, or TC series titanium alloy.

10. The in-situ one-time molding method for carbon fiber reinforced aluminum matrix composite material and titanium material with excellent bonding function according to claim 1, characterized in that: The aluminum material mentioned in step four is pure aluminum or aluminum alloy; the aluminum alloy is a 1xxx series aluminum alloy, a 2xxx series aluminum alloy, a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy.

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