A method for manufacturing a needled tubular fibrous base composite

Abstract

The application discloses a kind of preparation methods of needle-punched tubular fiber-based composite materials, and specific manufacturing steps include the following, step S1, fiber air-laying, fiber is transported to tin forest by air-laying equipment, and fiber is made to fall on the surface of drum from tin forest by air flow and float, the surface of drum has hole, and negative pressure is formed in inside by vacuum pump;Step S2, the needle-punched reinforcement of fiber web, tubular fiber web adsorbed on drum is reinforced using needle-punched equipment, and needle passes through the fiber web through the needle hole of the surface of drum, and repeatedly puncture reinforcement;Step S3, the RTM forming of tubular fiber-based composite material, places tubular fiber web after reinforcement into RTM equipment, injects resin and carries out solidification.The needle-punched reinforcement and RTM forming process of the application can significantly improve the mechanical properties of composite material, such as tensile strength, bending strength and tear strength, so as to make it more solid and durable, suitable for high load and high strength application scenarios.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of new material manufacturing, and in particular to a preparation method of a needled tubular fiber-based composite material. BACKGROUND

[0002] With the development of science and technology and industry, lightweight has become the goal pursued by multiple industries. Fiber-based tubular composite materials, especially carbon fiber composite material pipes, have become the preferred materials for lightweight design due to their high strength and lightweight characteristics. In the fields of automobiles, aerospace, robots and the like, lightweight design not only improves the performance of products, but also reduces energy consumption and cost. Therefore, fiber-based tubular composite materials have broad application prospects in these fields.

[0003] Traditional fiber-based composite materials are usually formed by manual laying and hot pressing, and the process is complex and the production efficiency is low. With the development of technology, needle-punched non-woven fabric has been widely studied as a fiber-reinforced material, which has the advantage of improving the mechanical properties of the material. However, the existing preparation method of needle-punched non-woven fabric still has some problems, such as uneven structure of the fabric, difficulty in forming a tubular structure, and further optimization of the performance and applicability of the composite material after needle reinforcement. Therefore, we propose a preparation method of a needled tubular fiber-based composite material. SUMMARY

[0004] To solve the above technical problems, the application adopts a modified technical solution, a preparation method of a needled tubular fiber-based composite material, and the specific manufacturing steps include the following.

[0005] Step S1, air laying of fibers, the fibers are conveyed to the cylinder through the air laying equipment, and the fibers are detached from the cylinder and fall onto the surface of the roller through the air flow, the surface of the roller has holes, and the inside is formed into negative pressure through a vacuum pump;

[0006] Step S2, needle reinforcement of the fiber web, the tubular fiber web adsorbed on the roller is reinforced by using a needle punching device, the needle passes through the fiber web through the needle holes on the surface of the roller, and repeatedly penetrates and reinforces;

[0007] Step S3, RTM forming of the tubular fiber-based composite material, the reinforced tubular fiber web is placed into an RTM device, resin is injected and cured, and a needled tubular fiber-based composite material is obtained;

[0008] S4, finished product inspection and post-processing.

[0009] As a further preferred mode of the present application, in step S1, the fiber raw material is selected, the fiber raw material is a mixture of polyester fiber, polypropylene fiber and glass fiber, the fiber diameter is 5-20μm, the fiber is guided to the surface of the cylinder through the air flow spinning equipment, the fiber is separated from the cylinder by air flow, the fiber forms a tubular fiber web under the action of gravity and air flow, the fiber web is uniformly distributed on the surface of the drum, the surface of the drum has pores, which can effectively help the fiber web to deposit on it, at the same time, the inside of the drum is connected to a vacuum pump to form a negative pressure, which further promotes the stable accumulation of the fiber web.

[0010] As a further preferred mode of the present application, in step S1, the air flow rate of the air flow forming equipment is 10-30m / s, and the rotating speed of the cylinder is 20-50rpm.

[0011] As a further preferred mode of the present application, in step S2, the fiber web is reinforced by the needle punching equipment, the needle is punched through the pores on the surface of the drum, the needle has a hook structure, which can repeatedly penetrate the fiber web and strengthen the entanglement between the fibers by hooking, the number, frequency, length and density of the needle can be adjusted according to the needs, the density of the needle is 1000-5000 needles / ㎡, the penetration depth is 1-10mm, the frequency is 200-1000 times / min, after the needle punching is completed, a needle-punched non-woven fabric with stable structure is formed.

[0012] As a further preferred mode of the present application, in step S3, the fiber web reinforced by needle punching is placed in a mold, the mold is designed in a tubular shape to wrap the fiber web, resin raw material is injected into the mold, epoxy resin or polyester resin is selected, the resin is uniformly penetrated into the fiber web through a vacuum guide system to ensure that the resin is fully integrated with the fiber web, the resin is cured by RTM process to form a solid tubular composite material, the curing temperature is usually 150-200℃, the curing time is 30-60 minutes, and the pressure is kept between 0.5-2MPa.

[0013] As a further preferred mode of the present application, in step S4, the mechanical properties of the formed tubular composite material are tested, including tensile strength, bending strength and tear strength, to ensure that the material meets the design requirements, then surface spraying, cutting and finally surface modification treatment are carried out to improve the corrosion resistance of the composite material.

[0014] As a further preferred mode of the present application, in step S4, the tensile strength of the tubular composite material is ≥50MPa, the bending strength is ≥80MPa, and the tear strength is ≥30N / mm.

[0015] As a further preferred mode of the present application, in step S4, laser cladding is further included, using a laser beam to locally melt the surface of the composite material, and at the same time introducing alloy powder or ceramic powder to form a wear-resistant or corrosion-resistant composite coating, laser power: 2000-5000W, scanning speed: 0.5-3m / min, scanning interval: 0.5-1mm; then laser hardening, using laser to quickly scan the surface of the composite material, heating it to high temperature, producing a surface hardening layer, hardening depth: 0.5-2mm, laser power: 2000-5000W, scanning speed: 0.5-3m / min.

[0016] Advantages

[0017] The present application provides a preparation method of needle-punched tubular fiber-based composite material. It has the following advantages:

[0018] The present application forms a fiber web into a tubular structure and stably accumulates it on a roller through an air-laid equipment, and then forms a stable non-woven fabric through needle punching reinforcement. This technical detail greatly improves the uniformity and strength of the fiber web. Vacuum suction and roller surface pores are used to help the uniform deposition of the fiber web, ensuring the structural stability of the material. Combination of resin injection and RTM process: the resin is uniformly infiltrated into the fiber web through the RTM process, ensuring the perfect combination of resin and fiber and solidifying into a solid tubular composite material. This method can precisely control the resin infiltration and avoid the uneven infiltration problem that may exist in traditional resin impregnation methods. Post-processing process for enhancing performance: the composite material is surface treated through laser cladding technology to enhance the wear resistance and corrosion resistance of the material. Precise adjustment of laser power and scanning speed can obtain ideal hardening layer and composite coating, further improving the performance of the composite material. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0020] The present application provides a technical solution: a preparation method of needle-punched tubular fiber-based composite material, the specific manufacturing steps include the following,

[0021] Step S1, air-laying of fibers, the fibers are transported to the cylinder through the air-laying equipment, and the fibers are detached from the cylinder and fall to the surface of the roller through air flow, the surface of the roller has holes, and the inside is formed into negative pressure through a vacuum pump;

[0022] Step S2, needle punching reinforcement of the fiber web, using a needle punching device to reinforce the tubular fiber web adsorbed on the drum, the needles pass through the fiber web through the needle holes on the surface of the drum and repeatedly penetrate to reinforce;

[0023] Step S3, RTM molding of the tubular fiber-based composite material, placing the reinforced tubular fiber web into the RTM device, injecting resin and curing to obtain a needle-punched tubular fiber-based composite material;

[0024] S4, finished product inspection and post-processing.

[0025] In step S1, the fiber raw material is selected, which is a mixture of polyester fiber, polypropylene fiber and glass fiber, with a fiber diameter of 5-20 μm. The fibers are guided to the surface of the cylinder by air spinning equipment, and the fibers are made to fall off the cylinder by air flow. The fibers form a tubular fiber web under the action of gravity and air flow. The fiber web is evenly distributed on the surface of the drum, which has pores that can effectively help the fiber web to deposit on it. At the same time, a negative pressure is formed in the drum by a vacuum pump to further promote the stable accumulation of the fiber web.

[0026] In step S1, the air flow rate of the air laying equipment is 10-30 m / s, and the cylinder rotation speed is 20-50 rpm.

[0027] In step S2, the fiber web is reinforced by the needle punching device through the pores on the surface of the drum. The needle has a hooking structure that can repeatedly penetrate the fiber web and strengthen the entanglement between the fibers. The number of needles, frequency, length and density of the needle can be adjusted as needed. The needle density is 1000-5000 needles / ㎡, the penetration depth is 1-10 mm, and the frequency is 200-1000 times / min. After needle punching, a structurally stable needle-punched nonwoven fabric is formed.

[0028] In step S3, the fiber web reinforced by needle punching is placed in a mold designed in a tubular shape to wrap the fiber web. Resin raw material is injected into the mold, and epoxy resin or polyester resin is selected. The resin is uniformly permeated into the fiber web through a vacuum guiding system to ensure complete fusion of the resin and the fiber web. The resin is cured by the RTM process to form a solid tubular composite material. The curing temperature is usually 150-200℃, the curing time is 30-60 minutes, and the pressure is maintained at 0.5-2 MPa.

[0029] In step S4, the mechanical properties of the formed tubular composite material are tested, including tensile strength, bending strength and tear strength, to ensure that the material meets the design requirements. Then surface spraying, cutting and finally surface modification treatment are carried out to improve the corrosion resistance of the composite material.

[0030] In step S4, the tensile strength of the tubular composite material is ≥ 50 MPa, the bending strength is ≥ 80 MPa, and the tear strength is ≥ 30 N / mm.

[0031] In step S4, laser cladding is also included, which locally melts the surface of the composite material using a laser beam and simultaneously introduces alloy powder or ceramic powder to form a wear-resistant or corrosion-resistant composite coating. The laser power is 2000-5000 W, the scanning speed is 0.5-3 m / min, and the scanning interval is 0.5-1 mm. Then, laser hardening is performed, which uses laser to quickly scan the surface of the composite material to heat it to a high temperature to produce a surface hardening layer. The hardening depth is 0.5-2 mm, the laser power is 2000-5000 W, and the scanning speed is 0.5-3 m / min.

[0032] Example One

[0033] A method for preparing a needle-punched tubular fiber-based composite material, raw material preparation:

[0034] Fiber raw material: a mixture of polyester fiber, polypropylene fiber and glass fiber is selected, and the diameter of the fiber is controlled to be 20 μm.

[0035] Resin raw material: epoxy resin is selected as the resin matrix.

[0036] Mold: a tubular mold for RTM molding.

[0037] Manufacturing steps:

[0038] Air-laid fiber

[0039] The mixed fiber material is guided to the cylinder through the air-laid equipment, and the cylinder rotation speed is set to 30 rpm and the air flow rate is 20 m / s.

[0040] Under the action of the air flow, the fibers fall off from the cylinder and are deposited on the surface of the drum to form a web. The surface of the drum has pores, and a negative pressure is formed by a vacuum pump to ensure that the fiber web is uniformly distributed and stably accumulated on the surface of the drum.

[0041] Needle-punched reinforcement of the fiber web

[0042] The needle-punching equipment is used, and the needle density is set to 3000 needles / ㎡, the penetration depth is 5 mm, and the frequency is 500 times / min.

[0043] The needles penetrate the fiber web through the pores on the surface of the drum, and the needle-punching reinforcement is repeated to form a stable non-woven fabric-like fiber web, ensuring that the fibers are well entangled and combined.

[0044] RTM molding of the tubular fiber-based composite material

[0045] The needle-reinforced fiber web is placed into a tubular RTM mold, ensuring that the fiber web is completely wrapped by the mold.

[0046] Epoxy resin is injected into the mold, and the resin uniformly penetrates into the fiber web through the vacuum guiding system.

[0047] At a temperature of 150°C, the pressure is maintained at 1 MPa for 45 minutes to ensure that the resin is completely fused and cured with the fiber web.

[0048] Product inspection and post-processing

[0049] Mechanical property testing is performed on the cured tubular composite material, and the test results are as follows:

[0050] Tensile strength: 55 MPa

[0051] Bending strength: 85 MPa

[0052] Tear strength: 35 N / mm

[0053] Surface spraying is performed on the composite material, and a strong corrosion-resistant coating is used to improve the durability of the material.

[0054] Laser cladding treatment is performed, using a laser power of 3000W, a scanning speed of 1m / min, and a scanning interval of 0.7mm to perform wear-resistant coating treatment on the surface of the composite material.

[0055] After laser hardening, the surface is heated to a high temperature using a laser, producing a surface hardening layer with a hardening depth of 1mm, enhancing the impact resistance and wear resistance of the material.

[0056] Finished product: The final tubular fiber-based composite material has excellent mechanical properties and corrosion resistance, suitable for high-strength structural materials, corrosion-resistant pipes, and other applications requiring enhanced mechanical properties.

[0057] Example Two

[0058] Raw material preparation:

[0059] Fiber raw material: A mixture of glass fiber, polypropylene fiber, and polyester fiber is selected, with a fiber diameter controlled at 5μm.

[0060] Resin raw material: Polyester resin is selected as the resin matrix.

[0061] Mold: A tubular mold for RTM molding, with an inner diameter of 50mm and a length of 300mm.

[0062] Manufacturing steps:

[0063] Step S1: Air laying of fibers

[0064] The mixed fiber material is transported to the cylinder through the air-laid equipment, the cylinder rotation speed is set to 25 rpm, and the air flow speed is set to 25 m / s.

[0065] Under the action of air flow, the fibers fall off and uniformly deposit on the surface of the perforated drum. The inside of the drum generates negative pressure through the vacuum pump, helping the fiber web to accumulate stably and form a uniform fiber web.

[0066] Step S2: Needle punching reinforcement of the fiber web

[0067] Using the needle punching equipment, set the needle density to 2000 needles / ㎡, the penetration depth to 3mm, and the frequency to 400 times / min.

[0068] The needle has a hooking structure, which repeatedly penetrates the fiber web through the pores on the surface of the drum to complete the reinforcement. The hooking action of the needle makes the entanglement between fibers more firm, ensuring the stability of the fiber web structure.

[0069] Step S3: RTM molding of tubular fiber-based composite material

[0070] Place the needle-reinforced fiber web into the tubular RTM mold to ensure that the fiber web completely wraps the mold.

[0071] Inject polyester resin, which uniformly penetrates into the fiber web through the vacuum guiding system, ensuring complete fusion between the resin and the fiber web.

[0072] At a curing temperature of 180℃, the curing time is set to 50 minutes, and the pressure in the mold is maintained at 1.5MPa. After the resin is completely cured, a solid tubular composite material is formed.

[0073] Step S4: finished product inspection and post-processing

[0074] Mechanical property tests are performed on the cured tubular composite material, and the test results are as follows:

[0075] Tensile strength: 60MPa

[0076] Bending strength: 90MPa

[0077] Tear strength: 40N / mm

[0078] The surface of the composite material is sprayed with an epoxy resin coating to improve its surface corrosion resistance.

[0079] Laser cladding treatment is performed with a laser power of 3500W, a scanning speed of 1.2m / min, and a scanning interval of 0.6mm to provide a composite coating on the surface of the composite material that is resistant to corrosion and wear.

[0080] Laser hardening is performed, using a laser to heat the surface to a high temperature, producing a surface hardened layer with a hardening depth of 1.5mm, further improving the material's impact resistance and surface hardness.

[0081] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be regarded as illustrative and non-restrictive in all respects. The scope of the present invention is defined by the appended claims rather than the foregoing description, and it is intended that all changes that come within the meaning and range of equivalents of the claims be included therein.

[0082] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for preparing a needle-punched tubular fiber-based composite material, characterized by: The specific production steps include the following: Step S1, air-laying of fibers, wherein the fibers are transported to a cylinder through an air-laying device, and the fibers are dropped from the cylinder by airflow and fall onto the surface of a drum. The surface of the drum has holes, and a vacuum pump is used to form a negative pressure inside the drum. Step S2, acupuncture reinforcement of the fiber web, using acupuncture equipment to reinforce the tubular fiber web adsorbed on the drum, with needles passing through the fiber web through the needle holes on the drum surface and repeatedly puncturing and reinforcing; Step S3, RTM molding of the tubular fiber-based composite material, placing the reinforced tubular fiber web into the RTM equipment, injecting resin and curing to obtain a needle-punched tubular fiber-based composite material; Step S4: finished product inspection and post-processing.

2. The method for preparing a needle-punched tubular fiber-based composite material according to claim 1, characterized in that: In step S1, a fiber raw material is selected. The fiber raw material is a mixture of polyester fiber, polypropylene fiber, and glass fiber. The fiber diameter is 5-20 μm. The fiber is guided to the surface of the cylinder through an air-jet spinning device. The air flow is used to make the fiber fall off the cylinder. The fibers form a tubular fiber web under the action of gravity and air flow. The fiber web is evenly distributed on the surface of the drum. The surface of the drum has pores, which can effectively help the fiber web to be deposited thereon. At the same time, a negative pressure is formed inside the drum through a vacuum pump to further promote the stable accumulation of the fiber web.

3. The method for preparing a needle-punched tubular fiber-based composite material according to claim 1, characterized in that: In step S1, the air flow rate of the air-laying equipment is 10-30 m / s, and the cylinder rotation speed is 20-50 rpm.

4. The method for preparing a needle-punched tubular fiber-based composite material according to claim 1, characterized in that: In step S2, the fiber web is reinforced by a needle device that pierces the pores on the surface of the drum. The needle has a hook structure that can repeatedly pierce the fiber web and strengthen the entanglement between the fibers through the hooking action. The number of needles, frequency, needle length and needle density of the needle reinforcement can be adjusted as needed. The needle density is 1000-5000 needles / ㎡, the piercing depth is 1-10mm, and the frequency is 200-1000 times / min. After the needling is completed, a needle-punched non-woven fabric with a stable structure is formed.

5. The method for preparing a needle-punched tubular fiber-based composite material according to claim 1, characterized in that: In step S3, the fiber mesh reinforced by needle punching is placed in a mold. The mold is designed to be tubular and can wrap the fiber mesh. Resin raw material is injected into the mold. Epoxy resin or polyester resin is selected. The resin is evenly infiltrated into the fiber mesh through a vacuum guide system to ensure that the resin and the fiber mesh are completely integrated. The resin is cured by the RTM process to form a strong tubular composite material. The curing temperature is usually 150-200°C, the curing time is 30-60 minutes, and the pressure is maintained between 0.5-2MPa.

6. The method for preparing a needle-punched tubular fiber-based composite material according to claim 1, characterized in that: In step S4, the formed tubular composite material is subjected to mechanical property tests, including tensile strength, bending strength, and tear strength, to ensure that the material meets the design requirements. The surface is then sprayed and cut, and finally surface modification treatment is performed to improve the corrosion resistance of the composite material.

7. The method for preparing a needle-punched tubular fiber-based composite material according to claim 1, characterized in that: In step S4, the tubular composite material has a tensile strength of ≥50 MPa, a flexural strength of ≥80 MPa, and a tear strength of ≥30 N / mm.

8. The method for preparing a needle-punched tubular fiber-based composite material according to claim 6, characterized in that: Step S4 also includes laser cladding of the material, using a laser beam to locally melt the surface of the composite material, and simultaneously introducing alloy powder or ceramic powder to form a wear-resistant or corrosion-resistant composite coating, laser power: 2000-5000W, scanning speed: 0.5-3m / min, scanning spacing: 0.5-1mm; then laser hardening is performed, using a laser to quickly scan the surface of the composite material, heating it to a high temperature to produce a surface hardened layer, hardening depth: 0.5-2mm, laser power: 2000-5000W, scanning speed: 0.5-3m / min.