Impact-resistant carbon fiber composite material and method of making the same
By employing aramid braided reinforced chopped carbon fiber prepreg and compression molding technology, the problems of impregnation effect and cost of carbon fiber composite materials have been solved, achieving efficient and low-cost improvement in impact resistance and damping effect, which is suitable for lightweighting of rail passenger cars and automobiles.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- THE QUARTERMASTER RES INST OF THE GENERAL LOGISTICS DEPT OF THE CPLA
- Filing Date
- 2026-04-02
- Publication Date
- 2026-06-05
AI Technical Summary
Existing carbon fiber composites have shortcomings in terms of impregnation effect and cost. In particular, continuous fiber prepregs are not impregnated sufficiently and are expensive, while chopped fiber prepregs have poor mechanical properties, making it difficult to simultaneously improve the impact resistance of the material and reduce the preparation cost.
Impact-resistant carbon fiber composites were prepared by wet blending short-cut carbon fiber and UHMWPE fiber using aramid braided surface-reinforced ultra-high molecular weight polyethylene (SCF/UHMWPE) prepreg. Combining compression molding technology, different layup structures were designed to enhance interfacial bonding.
It significantly improves the material's impact resistance and damping effect, reduces manufacturing costs, and has a simple process that is easy to scale up for production, resulting in good product performance consistency and stability.
Smart Images
Figure CN122143428A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of polymer materials technology, and in particular to an impact-resistant carbon fiber composite material and its preparation method. Background Technology
[0002] Carbon fiber prepreg, as an important component of composite materials, has attracted widespread attention due to its excellent performance, particularly high specific strength and specific stiffness. Aramid fibers, with their superior properties such as high strength, high modulus, high temperature resistance, and chemical corrosion resistance, are widely used in wear-resistant materials. Carbon fiber composites are favored by various industries due to their excellent comprehensive performance, especially in automotive lightweighting and rail transportation, where much research has been conducted. With the increasing global demand for carbon fiber prepreg and the national goals of carbon peaking and carbon neutrality, the efficient, low-cost, and industrialized preparation of carbon fiber prepreg and its composites will be a key focus of future research.
[0003] Carbon fiber thermoplastic composites (CFRTPs) can be categorized based on carbon fiber morphology into continuous fiber prepregs and chopped fiber prepregs. Continuous fiber prepregs exhibit high flexural and tensile strength, but their impregnation effect is difficult to guarantee, often resulting in insufficient impregnation in certain areas. Chopped fiber prepregs provide more thorough and uniform impregnation, but their mechanical properties are inferior to those of continuous fiber prepregs. The main forms of thermoplastic resins include resin powder, resin film, resin granules, and resin fiber. Resin powder offers better impregnation but is more expensive; resin film cannot precisely control the resin content while ensuring uniform impregnation; resin granules and resin fibers allow for accurate control of resin content and reduce costs, but their impregnation effect is generally less effective.
[0004] To address the challenges of poor impregnation of carbon fibers and high preparation costs due to the high viscosity of the molten state, it is urgent to develop a carbon fiber composite material that can improve the impact resistance of the material while reducing preparation costs and being energy-saving and environmentally friendly. Summary of the Invention
[0005] Based on the technical problems to be solved by the present invention, the present invention proposes an impact-resistant carbon fiber composite material and its preparation method. The impact-resistant carbon fiber composite material is prepared by using aramid braided surface-reinforced short-cut carbon fiber ultra-high molecular weight polyethylene (SCF / UHMWPE) prepreg. The SCF / UHMWPE prepreg is prepared by wet blending of short-cut carbon fiber and UHMWPE fiber. The material has advantages such as good damping effect and good impact resistance.
[0006] One objective of this invention is to provide an impact-resistant carbon fiber composite material, wherein the layup structure of the impact-resistant carbon fiber composite material is composed of aramid woven fabric and SCF / UHMWPE prepreg; the aramid woven fabric is composed of single-layer aramid woven fabric, double-layer aramid woven fabric, or multi-layer aramid woven fabric; the SCF / UHMWPE prepreg is a single-layer SCF / UHMWPE prepreg; the layup structure of the impact-resistant carbon fiber composite material includes double-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg-double-layer aramid woven fabric, single-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg-single-layer aramid woven fabric, single-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg, and double-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg.
[0007] Furthermore, the impact strength of the impact-resistant carbon fiber composite material is not less than 42.5. The tan value of the impact-resistant carbon fiber composite material is not less than 0.08.
[0008] A second objective of this invention is to provide a method for preparing impact-resistant carbon fiber composite materials, comprising: S1. Prepare a suspension system by placing short-cut carbon fibers in the suspension system and adding UHMWPE fibers into the suspension system uniformly mixed with the short-cut carbon fibers. Collect the mixed fibers to prepare carbon fiber felt, and then mold it to obtain SCF / UHMWPE prepreg. S2. Based on the SCF / UHMWPE prepreg, the impact-resistant carbon fiber composite material is prepared by compression molding.
[0009] Further, in the preparation of the suspension system, chopped carbon fibers are placed in the suspension system, UHMWPE fibers are added to the suspension system uniformly mixed with the chopped carbon fibers, the mixed fibers are collected, carbon fiber felt is prepared, and then molded to obtain SCF / UHMWPE prepreg, comprising: S11. Prepare a polyacrylamide dispersant with a concentration of 0.05~0.2 wt%; prepare a polyethylene glycol suspending agent with a concentration of 0.05~0.2 wt% to obtain a suspension; S12. Place the surface-treated short-cut carbon fibers into the suspension and, through ultrasound and / or stirring for 5-20 minutes, obtain a uniformly dispersed short-cut carbon fiber suspension. S13. Place the UHMWPE fibers that have been pre-dispersed in water into the uniformly dispersed short-cut carbon fiber suspension and stir continuously for 5 to 20 minutes to obtain mixed fibers. S14. Collect the mixed fibers using a filter screen and dry them at a constant temperature of 50~70℃ to obtain carbon fiber felt. S15. The carbon fiber felt is molded to obtain SCF / UHMWPE prepreg.
[0010] Further, the preparation of the impact-resistant carbon fiber composite material based on the SCF / UHMWPE prepreg by compression molding includes: S21. The SCF / UHMWPE prepreg is reinforced with the aramid woven fabric and then molded to obtain an impact-resistant carbon fiber composite material. S22. Prepare the impact-resistant carbon fiber composite material with different layup structures, and obtain carbon fiber composite materials with impact resistance that meet different requirements through performance analysis.
[0011] Furthermore, the chopped carbon fiber is modified chopped carbon fiber; the modified chopped carbon fiber is 3~7wt%KH550 modified chopped carbon fiber; the modification time is 2~6h.
[0012] Furthermore, the ultrasound and / or stirring time is 10 min.
[0013] Furthermore, the carbon fiber felt is molded at a temperature of 150~250℃, a pressure of 3~7MPa, and a time of 5~20min.
[0014] Furthermore, the SCF / UHMWPE prepreg is molded at a temperature of 150~250℃, a molding pressure of 0.5~2MPa, and a molding time of 5~20min.
[0015] The impact-resistant carbon fiber composite material described in this invention is suitable for the preparation of rail passenger car walls and automotive lightweighting.
[0016] Compared with the prior art, the present invention proposes an impact-resistant carbon fiber composite material and its preparation method, which has the following beneficial effects: The impact-resistant carbon fiber composite material proposed in this invention exhibits high impact performance. Through different layup structures, the interfacial bonding ability of the impact-resistant carbon fiber composite material is enhanced, with the optimal structure achieving an impact strength of 102.8. The material of this invention has a significantly improved impact resistance.
[0017] Furthermore, the impact-resistant carbon fiber composite material proposed in this invention has excellent damping effect, and the interface bonding performance of the gradient structure fiber composite material is excellent, which effectively enhances the damping effect of the material. Its tan value can reach 0.08, effectively reducing the energy consumption caused by material vibration.
[0018] Furthermore, the impact-resistant carbon fiber composite material proposed in this invention has a simple process, low cost, and is easy to mass-produce. It is prepared by compression molding technology, and all process parameters (such as modifier concentration, suspending agent concentration, molding temperature, molding pressure, molding time, etc.) are easy to control, ensuring the consistency and stability of product performance, while reducing production complexity and cost, making it suitable for mass production. Attached Figure Description
[0019] Figure 1 A schematic diagram of an impact-resistant carbon fiber composite material with different layup structures according to an embodiment of the present invention is shown.
[0020] Figure 2 A schematic diagram of an impact-resistant carbon fiber composite material with different layup structures, as shown in the comparative example of the present invention, is illustrated. Detailed Implementation
[0021] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.
[0022] Unless otherwise specified, the technical means used in the following embodiments are conventional means well known to those skilled in the art, and the reagents and materials in this invention are obtained from the market or other public channels.
[0023] The experimental materials and equipment involved in this invention mainly include, but are not limited to: Reagents and raw materials (see Table 1): Table 1 Main experimental reagents and raw materials Instruments (see Table 2): Table 2 Main Experimental Instruments The impact-resistant carbon fiber composite material and its preparation method described in this invention mainly include the following technical principles: Impact-resistant carbon fiber composites are prepared using aramid braided surface-reinforced chopped carbon fiber and ultra-high molecular weight polyethylene (SCF / UHMWPE) prepreg. The SCF / UHMWPE prepreg is prepared by wet blending of chopped carbon fiber and UHMWPE fiber, which significantly improves the impact resistance of the material while reducing the preparation cost. This invention enhances the interfacial bonding ability of the impact-resistant carbon fiber composite through different layup structure designs. The gradient structure fiber composite exhibits excellent interfacial bonding performance, effectively enhancing the damping effect of the material. The molding technology is used for preparation, and all process parameters (such as modifier concentration, suspending agent concentration, molding temperature, molding pressure, molding time, etc.) are easy to control, ensuring the consistency and stability of product performance, while reducing production complexity and cost, making it suitable for large-scale production.
[0024] Based on the above principles, this invention proposes an impact-resistant carbon fiber composite material and its preparation method, which includes the following steps: S1. Prepare a suspension system with a dispersant (polyacrylamide) concentration of 0.10 wt% and a suspending agent (polyethylene glycol) concentration of 0.01 wt%. Place surface-treated chopped carbon fibers into the suspension, start the ultrasonic equipment, and manually stir to achieve uniform dispersion of the chopped carbon fibers. Under the action of ultrasonic cavitation, the chopped carbon fibers float to the surface of the liquid. Check whether there are undispersed chopped carbon fibers at the bottom of the suspension. If there are still undispersed chopped carbon fibers, continue stirring until uniform dispersion. Then, add UHMWPE fibers pre-dispersed in water into the suspension and continue stirring until the fibers are uniformly dispersed. Finally, collect the mixed fibers using a filter screen, dry at a constant temperature of 60°C to obtain carbon fiber felt. Moldulate the carbon fiber felt according to appropriate molding parameters to obtain SCF / UHMWPE prepreg. S2. Impact-resistant carbon fiber composites were prepared by surface-reinforced SCF / UHMWPE prepregs with aramid braided fabrics; impact-resistant carbon fiber composites with different layup structures were prepared to obtain impact-resistant carbon fiber composites with impact resistance.
[0025] Schematic diagrams of impact-resistant carbon fiber composites with different layup structures are shown below. Figure 1 As shown, A represents a single-layer aramid woven fabric, AA represents a double-layer aramid woven fabric, and S represents a single-layer SCF / UHMWPE prepreg. Based on this, ASAAA represents a double-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg-double-layer aramid woven fabric structure; ASA represents a single-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg-single-layer aramid woven fabric structure; AS represents a single-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg structure; and AAS represents a double-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg structure.
[0026] Example 1 This invention proposes a method for preparing impact-resistant carbon fiber composite materials.
[0027] Mainly includes: (I) Preparation of SCF / UHMWPE prepreg This embodiment uses wet blending of chopped carbon fiber and UHMWPE fiber. The specific steps are as follows: 1.1 Prepare a deionized water-acetone mixed desizing solution at a mass ratio of 1:1; place a filter screen at the bottom of the mixed solution, and then immerse the carbon fiber in it. Wait 2 hours, then remove the carbon fiber and allow it to air dry naturally.
[0028] 1.2 Preparation of gradient concentration KH550 solutions: Weigh 26 ml of KH550 reagent and add it uniformly to the previously prepared anhydrous ethanol. Stir continuously during the addition process (stirring temperature: 25℃, stirring time: 1 min) to ensure thorough mixing of the reagents, ultimately preparing a 5 wt% KH550 solution. Cut the carbon fibers into fiber bundles 250 mm long and 50 mm wide, then immerse them in KH550 solutions of different concentrations for 4 h to obtain modified short-cut carbon fibers.
[0029] 1.3 A suspension system was prepared with a novel dispersant (polyacrylamide) concentration of 0.10 wt%, a suspending agent (polyethylene glycol) concentration of 0.01 wt%, and deionized water as the solute.
[0030] 1.4 Place the surface-treated chopped carbon fibers into the suspension, start the ultrasonic equipment, and manually stir to achieve uniform dispersion of the chopped carbon fibers. Continue ultrasonication and stirring for 10 minutes, and the chopped carbon fibers will float to the surface under the action of ultrasonic cavitation. Check the bottom of the suspension for any chopped carbon fibers that are stuck together. If there are still chopped carbon fibers stuck together, continue stirring until the chopped carbon fibers are clearly separated. Then, add the UHMWPE fibers that have been pre-dispersed in water into the suspension and continue stirring until the overall carbon fiber blend felt changes from black to gray.
[0031] 1.5 Using a 100mm×200mm×50mm filter frame, the entire suspension was poured into the filter frame. The remaining gray blended felt was placed in a constant temperature forced-air drying oven at 60℃ for 10 hours to obtain carbon fiber felt. The carbon fiber felt was then molded according to appropriate molding parameters: molding temperature 200℃, molding pressure 1MPa, and molding time 10min, ultimately yielding SCF / UHMWPE prepreg.
[0032] (II) Preparation of impact-resistant carbon fiber composite materials 2.1 Impact-resistant carbon fiber composites with different layup structures were classified according to... Figure 1Arrangement method. The specific arrangement method is as follows (taking the ASA structure as an example): First, place a layer of aramid woven fabric on the upper surface of the SCF / UHMWPE prepreg, and then place a layer of aramid woven fabric on the lower surface of the SCF / UHMWPE prepreg.
[0033] 2.2 The molding process parameters are set as follows: temperature 200℃, pressure 1MPa, time 5min. After molding is completed and the hot pressing program of the molding machine is finished, the mixture is cooled to room temperature to finally obtain impact-resistant carbon fiber composite material.
[0034] result: The impact resistance of the prepared impact-resistant carbon fiber composite material was tested: The impact resistance of carbon fiber composites with different layup structures was tested. The AASAA and ASA structures showed higher impact strength, while the AS and AAS structures showed poorer impact resistance. Because aramid braided fabric has higher impact resistance than chopped carbon fiber, the AAS structure exhibits superior impact resistance compared to the AS structure. The AASAA structure has higher impact strength than the ASA structure because the AASAA structure has more aramid braided fabric layers, which have higher impact resistance than chopped carbon fiber. However, it was observed that simply adding one A layer to the top and bottom of the ASA structure to create the AASAA structure only increased the impact strength from 102.8. Increased to 104.9 This indicates that the interfacial bonding between the AA layers is poor, resulting in little improvement in impact performance while significantly increasing cost. In contrast, the ASA structure exhibits a tighter interfacial bond and superior interfacial bonding performance. Therefore, the ASA structure represents the optimal layup structure that combines low cost and high performance. Table 3 provides the impact resistance properties of impact-resistant carbon fiber composites with different layup structures.
[0035] Table 3. Impact resistance properties of carbon fiber composites with different ply structures Example 2 This invention proposes another method for preparing impact-resistant carbon fiber composite materials.
[0036] Mainly includes: (I) Preparation of SCF / UHMWPE prepreg This embodiment uses wet blending of chopped carbon fiber and UHMWPE fiber. The specific steps are as follows: 1.1 Prepare a deionized water-acetone mixed desizing solution at a mass ratio of 1:1; place a filter screen at the bottom of the mixed solution, and then immerse the carbon fiber in it. Wait 2 hours, then remove the carbon fiber and allow it to air dry naturally.
[0037] 1.2 Preparation of KH550 solution: Weigh 44 ml of KH550 reagent and add it uniformly to 500 ml of previously prepared anhydrous ethanol. Stir continuously during the addition process (stirring temperature: 25℃, stirring time: 1 min) to ensure thorough mixing, ultimately preparing a 5 wt% KH550 solution. Cut the carbon fibers into fiber bundles 250 mm long and 50 mm wide, then immerse them in KH550 solutions of different concentrations for 4 h to obtain modified short-cut carbon fibers.
[0038] 1.3 A suspension system was prepared with a novel dispersant (polyacrylamide) concentration of 0.20 wt% and a suspending agent (polyethylene glycol) concentration of 0.005 wt%, and the solute was deionized water.
[0039] 1.4 Place the surface-treated chopped carbon fibers into the suspension, start the ultrasonic equipment, and manually stir to achieve uniform dispersion of the chopped carbon fibers. Continue ultrasonication and stirring for 10 minutes, and the chopped carbon fibers will float to the surface under the action of ultrasonic cavitation. Check the bottom of the suspension for any chopped carbon fibers that are stuck together. If there are still chopped carbon fibers stuck together, continue stirring until the chopped carbon fibers are clearly separated. Then, add the UHMWPE fibers that have been pre-dispersed in water into the suspension and continue stirring until the overall carbon fiber blend felt changes from black to gray.
[0040] 1.5 Using a 100mm×200mm×50mm filter frame, the entire suspension was poured into the filter frame. The remaining gray blended felt was placed in a constant temperature forced-air drying oven at 60℃ for 10 hours to obtain carbon fiber felt. The carbon fiber felt was then molded according to appropriate molding parameters: molding temperature 200℃, molding pressure 1MPa, and molding time 10min, ultimately yielding SCF / UHMWPE prepreg.
[0041] (II) Preparation of impact-resistant carbon fiber composite materials 2.1 Impact-resistant carbon fiber composites with different layup structures were classified according to... Figure 1 Arrangement method. The specific arrangement method is as follows (taking the ASA structure as an example): First, place a layer of aramid woven fabric on the upper surface of the SCF / UHMWPE prepreg, and then place a layer of aramid woven fabric on the lower surface of the SCF / UHMWPE prepreg.
[0042] 2.2 The molding process parameters are set as follows: temperature 200℃, pressure 1MPa, time 5min. After the hot pressing program of the molding machine is completed, it is cooled to room temperature to finally obtain impact-resistant carbon fiber composite material.
[0043] result: The impact resistance of the prepared impact-resistant carbon fiber composite material was tested: The impact resistance of carbon fiber composites with different layup structures was tested. The AASAA and ASA structures showed higher impact strength, while the AS and AAS structures showed poorer impact resistance. Because aramid braided fabric has higher impact resistance than chopped carbon fiber, the AAS structure exhibits superior impact resistance compared to the AS structure. The AASAA structure has higher impact strength than the ASA structure because the AASAA structure has more aramid braided fabric layers, which have higher impact resistance than chopped carbon fiber. However, it was observed that simply adding one A layer to the top and bottom of the ASA structure to create the AASAA structure only increased the impact strength from 96.8. Increased to 99.7 This indicates that the interfacial bonding between the AA layers is poor, resulting in little improvement in impact performance while significantly increasing cost. In contrast, the ASA structure exhibits a tighter interfacial bond and superior interfacial bonding performance. Therefore, the ASA structure represents the optimal layup structure, combining low cost and high performance. Table 4 provides the impact resistance properties of impact-resistant carbon fiber composites with different layup structures.
[0044] Table 4. Impact Resistance Properties of Carbon Fiber Composites with Different Ply Structures Example 3 This invention proposes another method for preparing impact-resistant carbon fiber composite materials.
[0045] Mainly includes: (I) Preparation of SCF / UHMWPE prepreg This embodiment uses wet blending of chopped carbon fiber and UHMWPE fiber. The specific steps are as follows: 1.1 Prepare a deionized water-acetone mixed desizing solution at a mass ratio of 1:1; place a filter screen at the bottom of the mixed solution, and then immerse the carbon fiber in it. Wait 2 hours, then remove the carbon fiber and allow it to air dry naturally.
[0046] 1.2 Preparation of KH550 solution: Weigh 10 ml of KH550 reagent and add it evenly to 500 ml of previously prepared anhydrous ethanol. Stir continuously during the addition process (stirring temperature: 25℃, stirring time: 1 min) to ensure thorough mixing of the reagent, ultimately preparing a 2 wt% KH550 solution. Cut the carbon fibers into fiber bundles 250 mm long and 50 mm wide, then immerse them in KH550 solutions of different concentrations for 4 h to obtain modified short-cut carbon fibers.
[0047] 1.3 A suspension system was prepared with a novel dispersant (polyacrylamide) concentration of 0.05 wt% and a suspending agent (polyethylene glycol) concentration of 0.02 wt%, with deionized water as the solute.
[0048] 1.4 Place the surface-treated chopped carbon fibers into the suspension, start the ultrasonic equipment, and manually stir to achieve uniform dispersion of the chopped carbon fibers. Continue ultrasonication and stirring for 10 minutes, and the chopped carbon fibers will float to the surface under the action of ultrasonic cavitation. Check the bottom of the suspension for any chopped carbon fibers that are stuck together. If there are still chopped carbon fibers stuck together, continue stirring until the chopped carbon fibers are clearly separated. Then, add the UHMWPE fibers that have been pre-dispersed in water into the suspension and continue stirring until the overall carbon fiber blend felt changes from black to gray.
[0049] 1.5 Using a 100mm×200mm×50mm filter frame, the entire suspension was poured into the filter frame. The remaining gray blended felt was placed in a constant temperature forced-air drying oven at 60℃ for 10 hours to obtain carbon fiber felt. The carbon fiber felt was then molded according to appropriate molding parameters: molding temperature 200℃, molding pressure 1MPa, and molding time 10min, ultimately yielding SCF / UHMWPE prepreg.
[0050] (II) Preparation of impact-resistant carbon fiber composite materials 2.1 Impact-resistant carbon fiber composites with different layup structures were classified according to... Figure 1 Arrangement method. The specific arrangement method is as follows (taking the ASA structure as an example): First, place a layer of aramid woven fabric on the upper surface of the SCF / UHMWPE prepreg, and then place a layer of aramid woven fabric on the lower surface of the SCF / UHMWPE prepreg.
[0051] 2.2 The molding process parameters are set as follows: temperature 200℃, pressure 1MPa, time 5min. After the hot pressing program of the molding machine is completed, it is cooled to room temperature to finally obtain impact-resistant carbon fiber composite material.
[0052] result: The impact resistance of the prepared impact-resistant carbon fiber composite material was tested: The impact resistance of carbon fiber composites with different layup structures was tested. The AASAA and ASA structures showed higher impact strength, while the AS and AAS structures showed poorer impact resistance. Because aramid braided fabric has higher impact resistance than chopped carbon fiber, the AAS structure exhibits superior impact resistance compared to the AS structure. The AASAA structure has higher impact strength than the ASA structure because the AASAA structure has more aramid braided fabric layers, which have higher impact resistance than chopped carbon fiber. However, it was observed that simply adding one A layer to the top and bottom of the ASA structure to create the AASAA structure only increased the impact strength from 93.1. Increased to 96.5 This indicates that the interfacial bonding between the AA layers is poor, resulting in little improvement in impact performance while significantly increasing cost. In contrast, the ASA structure exhibits a tighter interfacial bond and superior interfacial bonding performance. Therefore, the ASA structure represents the optimal layup structure for both low cost and high performance. Table 5 provides the impact resistance properties of impact-resistant carbon fiber composites with different layup structures.
[0053] Table 5. Impact resistance properties of carbon fiber composites with different ply structures Comparative Example This invention presents a comparative test of an impact-resistant carbon fiber composite material.
[0054] Mainly includes: (I) Preparation of SCF / PP prepreg This embodiment uses a wet blending process to combine short-cut carbon fiber and PP fiber. The specific steps are as follows: 1.1 Prepare a deionized water-acetone mixed desizing solution at a mass ratio of 1:1; place a filter screen at the bottom of the mixed solution, and then immerse the carbon fiber in it. Wait 2 hours, then remove the carbon fiber and allow it to air dry naturally.
[0055] 1.2 Preparation of KH550 solution: Weigh 26 ml of KH550 reagent and add it uniformly to 500 ml of previously prepared anhydrous ethanol. Stir continuously during the addition process (stirring temperature: 25℃, stirring time: 1 min) to ensure thorough mixing of the reagents, ultimately preparing a 5 wt% KH550 solution. Cut the carbon fibers into fiber bundles 250 mm long and 50 mm wide, then immerse them in KH550 solutions of different concentrations for 4 h to obtain modified short-cut carbon fibers.
[0056] 1.3 A suspension system was prepared with a novel dispersant (polyacrylamide) concentration of 0.10 wt% and a suspending agent (polyethylene glycol) concentration of 0.01 wt%, with deionized water as the solute.
[0057] 1.4 Place the surface-treated chopped carbon fibers into the suspension, start the ultrasonic equipment, and manually stir to achieve uniform dispersion of the chopped carbon fibers. Continue ultrasonication and stirring for 10 minutes, and the chopped carbon fibers will float to the surface under the action of ultrasonic cavitation. Check the bottom of the suspension for any chopped carbon fibers that are stuck together. If there are still chopped carbon fibers stuck together, continue stirring until the chopped carbon fibers are clearly separated. Then, add the PP fibers that have been pre-dispersed in water into the suspension and continue stirring until the overall carbon fiber blend felt changes from black to gray.
[0058] 1.5 Using a 100mm×200mm×50mm filter frame, the entire suspension was poured into the filter frame. The remaining gray blended felt was placed in a constant temperature forced-air drying oven, set at 60℃, and dried for 10 hours to obtain carbon fiber felt. The carbon fiber felt was then molded according to appropriate molding parameters: molding temperature 200℃, molding pressure 1MPa, and molding time 10min, ultimately yielding SCF / PP prepreg.
[0059] (II) Preparation of impact-resistant carbon fiber composite materials 2.1 Impact-resistant carbon fiber composites with different layup structures were classified according to... Figure 2 Arrangement method. The specific arrangement method is as follows (taking the ASA structure as an example): first, place a layer of aramid woven fabric on the upper surface of the SCF / PP prepreg, and then place a layer of aramid woven fabric on the lower surface of the SCF / PP prepreg.
[0060] 2.2 The molding process parameters are set as follows: temperature 200℃, pressure 1MPa, time 5min. After the hot pressing program of the molding machine is completed, it is cooled to room temperature to finally obtain impact-resistant carbon fiber composite material.
[0061] result: The impact resistance of the prepared impact-resistant carbon fiber composite material was tested: The impact resistance of carbon fiber composites with different layup structures was tested. The AASAA and ASA structures showed higher impact strength, while the AS and AAS structures showed poorer impact resistance. Because aramid braided fabric has higher impact resistance than chopped carbon fiber, the AAS structure exhibits superior impact resistance compared to the AS structure. The AASAA structure has higher impact strength than the ASA structure because the AASAA structure has more aramid braided fabric layers, which have higher impact resistance than chopped carbon fiber. However, it was observed that simply adding one A layer to the top and bottom of the ASA structure to create the AASAA structure only increased the impact strength from 70.3. Increased to 75.6 This indicates that the interfacial bonding between the AA layers is poor, resulting in little improvement in impact performance while significantly increasing cost. In contrast, the ASA structure exhibits a tighter interfacial bond and superior interfacial bonding performance. Therefore, the ASA structure represents the optimal layup structure that combines low cost and high performance. Table 6 provides the impact resistance properties of impact-resistant carbon fiber composites with different layup structures.
[0062] Table 6. Impact Resistance Properties of Carbon Fiber Composites with Different Ply Structures It should be noted that the term "comprising," or any other variation thereof, is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0063] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.
Claims
1. An impact-resistant carbon fiber composite material, characterized in that, The impact-resistant carbon fiber composite material has a layup structure consisting of aramid woven fabric and SCF / UHMWPE prepreg; The aramid woven fabric is composed of a single-layer aramid woven fabric, a double-layer aramid woven fabric, or a multi-layer aramid woven fabric. The SCF / UHMWPE prepreg is a single-layer SCF / UHMWPE prepreg. The impact-resistant carbon fiber composite material has a layup structure including double-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg-double-layer aramid woven fabric, single-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg-single-layer aramid woven fabric, single-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg, and double-layer aramid woven fabric-single-layer SCF / UHMWPE prepreg.
2. The impact-resistant carbon fiber composite material according to claim 1, characterized in that, The impact strength of the impact-resistant carbon fiber composite material is not less than 42.
5. The tan value of the impact-resistant carbon fiber composite material is not less than 0.
08.
3. A method for preparing the impact-resistant carbon fiber composite material according to claim 1 or 2, characterized in that, include: S1. Prepare a suspension system by placing short-cut carbon fibers in the suspension system and adding UHMWPE fibers into the suspension system uniformly mixed with the short-cut carbon fibers. Collect the mixed fibers to prepare carbon fiber felt, and then mold it to obtain SCF / UHMWPE prepreg. S2. Based on the SCF / UHMWPE prepreg, the impact-resistant carbon fiber composite material is prepared by compression molding.
4. The method for preparing the impact-resistant carbon fiber composite material according to claim 3, characterized in that, The preparation of the suspension system involves placing chopped carbon fibers in the suspension system, adding UHMWPE fibers to the suspension system uniformly mixed with the chopped carbon fibers, collecting the mixed fibers, preparing carbon fiber felt, and molding it to obtain SCF / UHMWPE prepreg, comprising: S11. Prepare a polyacrylamide dispersant with a concentration of 0.05~0.2 wt%; prepare a polyethylene glycol suspending agent with a concentration of 0.05~0.2 wt% to obtain a suspension; S12. Place the surface-treated short-cut carbon fibers into the suspension and, through ultrasound and / or stirring for 5-20 minutes, obtain a uniformly dispersed short-cut carbon fiber suspension. S13. Place the UHMWPE fibers that have been pre-dispersed in water into the uniformly dispersed short-cut carbon fiber suspension and stir continuously for 5 to 20 minutes to obtain mixed fibers. S14. Collect the mixed fibers using a filter screen and dry them at a constant temperature of 50~70℃ to obtain carbon fiber felt. S15. The carbon fiber felt is molded to obtain SCF / UHMWPE prepreg.
5. The method for preparing the impact-resistant carbon fiber composite material according to claim 3, characterized in that, The preparation of the impact-resistant carbon fiber composite material based on the SCF / UHMWPE prepreg through compression molding includes: S21. The SCF / UHMWPE prepreg is reinforced with the aramid woven fabric and then molded to obtain an impact-resistant carbon fiber composite material. S22. Prepare the impact-resistant carbon fiber composite material with different layup structures to obtain a carbon fiber composite material whose impact resistance meets different requirements.
6. The method for preparing the impact-resistant carbon fiber composite material according to claim 3, characterized in that, The chopped carbon fiber is a modified chopped carbon fiber; The modified short-cut carbon fiber is 3~7Wt%KH550 modified short-cut carbon fiber; the modification time is 2~6h.
7. The method for preparing the impact-resistant carbon fiber composite material according to claim 3, characterized in that, The ultrasound and / or stirring time is 5-15 min.
8. The method for preparing the impact-resistant carbon fiber composite material according to claim 3, characterized in that, The carbon fiber felt is molded at a temperature of 150~250℃.
9. The method for preparing the impact-resistant carbon fiber composite material according to claim 8, characterized in that, The molding pressure is 3~7MPa; the molding time is 5~20min.
10. The method for preparing the impact-resistant carbon fiber composite material according to claim 3, characterized in that, The SCF / UHMWPE prepreg is molded at a temperature of 150~250℃, a pressure of 0.5~2MPa, and a time of 5~20min.