Carbon fiber composite material rail traffic part forming process and mold system

Abstract

The invention discloses a carbon fiber composite material track traffic part forming process and a mold system, and belongs to the technical field of track traffic part manufacturing. The process comprises the following steps: laying carbon fiber layers according to an asymmetric quasi-isotropic sequence, and inserting a nano modified release film between adjacent carbon fiber layers to form a prepreg laying layer and carrying out pre-compaction; the pre-compacted prepreg laying layer is put into a mold, and multi-stage vacuum synergistic resin pouring is carried out; heating the mold, and cooling and demolding after the resin is cured; wherein in the heating process, the real-time curing degree is utilized, and the temperature rise rate is dynamically adjusted through an improved fuzzy PID algorithm. The efficiency and quality in the forming process of the rail traffic component can be improved, and the technical bottlenecks of low efficiency and non-uniform performance of a traditional process are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of rail transit component manufacturing, and particularly to a forming process and a mold system for rail transit components made of carbon fiber composite materials. Background Art

[0002] The statements in this section merely mention the background art related to the present invention and do not necessarily constitute prior art.

[0003] When using carbon fiber composite materials to perform the forming process of rail transit components, it is mostly to introduce resin into a closed mold through vacuum negative pressure, impregnate the fiber reinforced material and then cure and form; the core is to form a pressure difference through vacuum pumping to drive the resin to flow and remove air bubbles, including processes such as layup, sealing, perfusion, curing, and demolding.

[0004] However, in the existing forming process, during the perfusion process, the response of the vacuum system has a delay, resulting in resin overflow or dry spots; and during the curing process, the rheological properties of the resin are not considered, and the heating section accounts for 60% of the total cycle, which is too long and affects the curing efficiency. Summary of the Invention

[0005] In order to solve the deficiencies of the existing technology, the present invention provides a forming process and a mold system for rail transit components made of carbon fiber composite materials, which improve the forming efficiency and quality and reduce energy consumption through multi-stage vacuum collaborative ultrasonic activation, gradient temperature adjustment in response to real-time curing degree, and bionic vein structure micro-channel design for resin perfusion.

[0006] In the first aspect, the present invention provides a forming process for rail transit components made of carbon fiber composite materials;

[0007] A forming process for rail transit components made of carbon fiber composite materials includes:

[0008] Laying carbon fiber layers in an asymmetric quasi-isotropic order, and inserting a nano-modified release film between adjacent carbon fiber layers to form a prepreg layup and perform pre-compaction;

[0009] Putting the pre-compacted prepreg layup into a mold and performing multi-stage vacuum collaborative resin perfusion;

[0010] Heating the mold to cure the resin and then cooling and demolding;

[0011] Wherein, during the heating process, the heating rate is dynamically adjusted by an improved fuzzy PID algorithm using the real-time curing degree.

[0012] In some embodiments, the asymmetric quasi-isotropic order is [0° / 45° / 90° / -45°]n, where n = 2 to 4.

[0013] In some embodiments, putting the pre-compacted prepreg ply into a mold and performing multi-stage vacuum-assisted resin infusion includes:

[0014] Putting the pre-compacted prepreg ply into a mold, adjusting the vacuum degree in the mold to a first vacuum threshold, and performing constant-temperature preheating on the mold at a first temperature threshold;

[0015] Adjusting the vacuum degree in the mold to a second vacuum threshold, and starting an ultrasonic generator for improving the resin flow uniformity;

[0016] Adjusting the vacuum degree in the mold to a third vacuum threshold at a preset pressure reduction rate.

[0017] In some embodiments, the first vacuum threshold is -0.093 Mpa to -0.097 Mpa, the second vacuum threshold is -0.098 Mpa to -0.102 Mpa, the third vacuum threshold is -0.078 Mpa to -0.082 Mpa, and the first temperature threshold is 58 °C to 62 °C.

[0018] In some embodiments, using the real-time degree of cure and dynamically adjusting the heating rate through an improved fuzzy PID algorithm includes:

[0019] Calculating the cure degree deviation, the cure degree change rate, and the abnormal fluctuation of the dielectric signal according to the real-time degree of cure and the real-time dielectric loss factor;

[0020] Determining the control parameter adjustment amount for the cure degree deviation, the cure degree change rate, and the abnormal fluctuation of the dielectric signal based on a preset membership function and fuzzy matching rules;

[0021] Based on the control parameter adjustment amount, outputting a control heating power through a PID controller to adjust the heating temperature;

[0022] Wherein, the membership function and the fuzzy matching rules are constructed in combination with the curing reaction kinetic characteristics of the resin.

[0023] In some embodiments, the thickness of the nano-modified release film is 0.03 mm to 0.07 mm.

[0024] In some embodiments, the resin is infused into the mold through a microchannel unit, and the microchannel unit has a biomimetic leaf vein fractal structure.

[0025] In a second aspect, the present invention provides a mold system;

[0026] A mold system, based on the above-mentioned forming process of carbon fiber composite rail transit components, includes:

[0027] A substrate, the substrate is provided with a mold cavity, and the mold cavity has an accommodation space for a prepreg layer and resin; the substrate is provided with a vacuum pressure closed-loop module and a partition heating module;

[0028] An upper cover, the upper cover plate is arranged on the substrate, and the upper cover plate is provided with a valve for pouring resin;

[0029] A microchannel unit, the microchannel unit is communicated with the valve, and the microchannel unit has a bionic leaf vein fractal structure.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. The technical solution provided by the present invention pre-compacts the prepreg layer to eliminate the interlayer gap; divides the multi-stage vacuum degree, and synergistically switches the vacuum degree gradient and ultrasonic activation during the resin infusion process to break through the resin viscosity-flow rate coupling bottleneck; during the curing process, based on the real-time cure degree feedback, the heating rate is dynamically adjusted by an improved fuzzy PID algorithm to reduce the curing energy consumption.

[0032] 2. The technical solution provided by the present invention transports the resin through the microchannel with a bionic leaf vein structure, which can reduce bubble defects and improve the encapsulation uniformity, and avoid dry spot defects.

[0033] 3. The technical solution provided by the present invention improves the fuzzy PID algorithm by combining the real-time cure degree collected by the dielectric sensor and the curing reaction kinetic characteristics of the resin, so that the temperature change better fits the real curing process of the resin, and at the same time, reduces the energy consumption. Description of the Drawings

[0034] The specification drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0035] Figure 1 It is a schematic flow chart of the forming process of the carbon fiber composite rail transit component provided by the embodiment of the present invention. Detailed Embodiments

[0036] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further descriptions of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0037] Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0038] Embodiment 1

[0039] The forming quality and forming efficiency of the existing forming processes for rail transit components need to be improved. Therefore, the present invention provides a forming process for rail transit components made of carbon fiber composite materials.

[0040] Next, in combination with Figure 1 A forming process for rail transit components made of carbon fiber composite materials disclosed in this embodiment will be described in detail. The forming process for rail transit components made of carbon fiber composite materials includes:

[0041] S1. Lay the carbon fiber layers in an asymmetric quasi-isotropic order, and insert a nano-modified release film between adjacent carbon fiber layers to form a prepreg ply and perform pre-compaction.

[0042] Specifically, the asymmetric quasi-isotropic order is [0° / 45° / 90° / -45°]n, where n = 2 to 4; the thickness of the nano-modified release film is 0.05 mm. The nano-modified release film is a release film containing 5 wt% SiO2 nanoparticles, and the particle size of the nanoparticles is 50 nm; the carbon fiber is T800SC carbon fiber.

[0043] Exemplarily, lay the carbon fiber layers in the order of [0° / 45° / 90° / -45°]3, and insert a nano-modified release film between adjacent carbon fiber layers to form a prepreg ply; then perform pre-compaction on the prepreg ply under a pressure of 0.5 MPa for 3 min to eliminate the interlayer gap and ensure that the fiber volume content V f = 60 ± 1%.

[0044] Before that, the carbon fiber layers need to be cut according to the design requirements of the part (such as the size of the rail transit component).

[0045] S2. Put the pre-compacted prepreg ply into a mold and perform multi-stage vacuum collaborative resin infusion. Specifically, it includes:

[0046] Stage 1 (preheating and infiltration): Put the pre-compacted prepreg ply into a mold and seal the mold to form a vacuum cavity. Continuously infuse the resin into the mold through the micro-channel unit, adjust the vacuum degree in the mold to the first vacuum threshold, and perform constant-temperature preheating on the mold at the first temperature threshold.

[0047] Here, preheating is combined to promote the initial fluidity of the resin.

[0048] Stage 2 (dynamic infiltration): Adjust the vacuum degree in the mold to the second vacuum threshold, and start an ultrasonic generator for improving the resin flow uniformity.

[0049] In this stage, the vibration of the ultrasonic generator is used to improve the resin flow uniformity and reduce bubbles. At the same time, the vacuum degree is increased to enhance the resin flow rate and accelerate the resin infiltration of the prepreg ply.

[0050] Stage 3 (gradient pressure application): Adjust the vacuum degree in the mold to the third-stage vacuum threshold value at a preset pressure reduction rate.

[0051] In some embodiments, the first-stage vacuum threshold value is -0.093 Mpa to -0.097 Mpa, the second-stage vacuum threshold value is -0.098 Mpa to -0.102 Mpa, the third-stage vacuum threshold value is -0.078 Mpa to -0.082 Mpa, the first temperature threshold value is 58 °C to 62 °C, and the pressure reduction rate is 0.018 MPa / min to 0.022 MPa / min.

[0052] Exemplarily, in Stage 1, the first-stage vacuum threshold value is -0.095 Mpa, the mold is preheated to 60 °C, after the vacuum degree rises to -0.095 Mpa and is kept at a constant temperature for 10 min, it switches to Stage 2; in Stage 2, the vacuum degree is increased to -0.1 MPa, the ultrasonic generator is started synchronously, the frequency of the ultrasonic generator is 20 kHz ± 5%, and the power density is 2 W / cm² to increase the resin flow uniformity to 1.2 m / min; when the resin fills more than 90% of the mold cavity, it switches to Stage 3; in Stage 3, the vacuum degree is reduced to -0.08 MPa at a pressure reduction rate of 0.02 MPa / min to prevent the residual of microbubbles.

[0053] Here, the vacuum is pumped by controlling the high-speed solenoid valve (response time ≤ 50 ms) installed in the mold, and the vacuum degree data is collected by the piezoelectric ceramic sensor (accuracy ±0.001 MPa). Through the "synergistic mechanism of ultrasonic activation + vacuum gradient switching", the resin viscosity-flow rate coupling bottleneck is broken through, and it is verified by CFD simulation that the flow uniformity > 95%.

[0054] S3. Heat the mold to cure the resin and then cool it to demold; during the heating process, use the real-time degree of cure and dynamically adjust the heating rate through the improved fuzzy PID algorithm.

[0055] In this embodiment, in order to reduce the curing energy consumption, the temperature gradient adjustment is carried out during the resin curing process through the improved fuzzy PID algorithm. As an implementation manner, dynamically adjusting the heating rate through the improved fuzzy PID algorithm includes:

[0056] Step 1. Obtain the real-time degree of cure during the resin heating process.

[0057] In this embodiment, the real-time degree of cure during the resin heating process is collected by the dielectric sensor installed inside the mold. The offset amount of the dielectric loss peak position of the dielectric sensor has an exponential relationship with the degree of cure, which is expressed as:

[0058]

[0059] Wherein, α represents the degree of curing, k represents the curing kinetic constant, D0 represents the initial loss factor, and D peak represents the real-time dielectric loss factor.

[0060] Here, the above relationship is established through experimental calibration, and the curing kinetic constant needs to be calibrated by DSC (Differential Scanning Calorimetry).

[0061] Furthermore, in order to eliminate the influence of high-frequency electromagnetic interference on the feedback of the degree of curing, before obtaining the real-time degree of curing, it also includes: using wavelet transform to denoise the dielectric signal and extracting the effective frequency band (such as 1 - 10 kHz).

[0062] Step 2: Calculate the curing degree deviation, the curing degree change rate, and the abnormal fluctuation of the dielectric signal according to the real-time degree of curing and the real-time dielectric loss factor.

[0063] In this embodiment, the curing degree deviation is expressed as:

[0064] Δα = α set - α t ;

[0065] Wherein, Δα represents the difference in the degree of curing, and α t represents the degree of curing at time t, and α set represents the target degree of curing.

[0066] The curing degree change rate α ’ is expressed as:

[0067]

[0068] The abnormal fluctuation D of the dielectric signal ’ is expressed as:

[0069]

[0070] Wherein, ΔD represents the change amount of the loss factor.

[0071] Step 3: Perform fuzzy matching on the curing degree deviation, the curing degree change rate, and the abnormal fluctuation of the dielectric signal based on a preset membership function and a fuzzy rule base to determine the control parameter adjustment amount.

[0072] The kinetic characteristics of the resin curing reaction include an initial stage, a rapid curing stage, and a post-curing stage. In the initial stage, the resin has a high viscosity and needs to be heated rapidly; in the rapid curing stage, the cross-linking reaction is intense and stable temperature control is required; in the post-curing stage, residual stress is inhibited and deceleration is required. Furthermore, considering the kinetic characteristics of the resin curing reaction, the membership function in this embodiment is designed as follows:

[0073] 1. Definition of input variables and division of the universe of discourse:

[0074] (1) Input variables:

[0075] The curing degree deviation Δα, the universe of discourse can be set as [-0.3, 0.3], corresponding to the actual curing degree deviation range.

[0076] The curing degree change rate α ’ , the universe of discourse can be set as [-10%, 10%], covering the curing rate fluctuation range.

[0077] The dielectric signal fluctuation D ’ , the universe of discourse can be set as [-0.2, 0.2], reflecting the abnormal change of the dielectric loss factor.

[0078] (2) Fuzzy language variables: The curing degree deviation is divided into 7 fuzzy subsets: {Negative Big (NB), Negative Medium (NM), Negative Small (NS), Zero (ZO), Positive Small (PS), Positive Medium (PM), Positive Big (PB)}, the curing degree change rate is divided into 3 fuzzy subsets {Slow, Medium, Fast}, and the dielectric signal fluctuation is divided into three fuzzy subsets {Low, Mid, High}, {Low (NB / NS), Mid (ZO), High (PS / PB)}, to cover the non-linear dynamic characteristics.

[0079] 2. Membership function types and parameters:

[0080] For the curing degree deviation Δα and the curing degree change rate α ’ , a triangular membership function is adopted, because its calculation is simple and suitable for real-time control. For example, the "Zero (ZO)" interval of the curing degree deviation Δα is [-0.05, 0.05], the vertex of the membership function is at 0, and the base width is ±0.05.

[0081] For the dielectric signal fluctuation D ’ , a Gaussian membership function is adopted to enhance the robustness to noise; for example, the "Positive Big (PB)" function center of the dielectric signal fluctuation D ’ is 0.2, and the standard deviation is 0.05, covering the extreme cases of dielectric signal mutation.

[0082] The fuzzy rule base in this embodiment is designed as follows:

[0083] A two-layer rule design is adopted. In the first layer, according to the curing degree deviation Δα and the curing degree change rate α ’ adjust the proportional gain K p and the integral time T i , in the second layer, according to the dielectric signal fluctuation D ’ adjust the differential gain K d , to suppress the abnormal fluctuation of the dielectric signal.

[0084] Exemplarily, the first layer partial rules are expressed as follows:

[0085]

[0086]

[0087] When Δα is large but α ’ Small, that is, the error is large but changes slowly, and the proportional gain (K p =PB) to speed up the response and turn off the integral action (K i =NB) to avoid integral windup.

[0088] When Δα is small but α ’ If the error is close to the target but changes dramatically, the proportional gain (K p =NS) to suppress overshoot and enhance the integral effect (K i =PS) to eliminate steady-state errors.

[0089] The second part of the rules is expressed as follows:

[0090] D′ Low Mid High <![CDATA[K d Adjustment amount]]> <![CDATA[K d = NB]]> <![CDATA[K d = ZO]]> <![CDATA[K d = PB]]>

[0091] When the dielectric signal fluctuates greatly, that is, abnormal resin flow is detected (there may be bubbles or local non-wetting), the differential gain (K d =PB) to enhance system damping and suppress local temperature fluctuations.

[0092] When the dielectric signal fluctuation is low, that is, the signal is stable, reduce the differential gain (K d =NB) Avoid being overly sensitive.

[0093] Here, fuzzy control rules can be added in the fuzzy rule editor of the Fuzzy Control Toolbox in MATLAB.

[0094] As an implementation method, step 2 is specifically as follows: synthesizing the output membership through fuzzy rules, converting the fuzzy output into an accurate PID parameter increment using the center of gravity method, and controlling the heating power of the heating module installed on the mold through the PID controller.

[0095] For example, the proportional gain increment ΔK p It is expressed as:

[0096] In the formula, μ i represents the i-th membership, K p,i represents the i-th proportional gain.

[0097] Integration time increment ΔT i It is expressed as:

[0098]

[0099] In the formula, μ j represents the j-th membership degree, and T i,j represents the j-th integral time

[0100] The differential gain increment ΔK d is expressed as:

[0101]

[0102] In the formula, K d,i represents the i-th differential gain.

[0103] Based on this, through D ’ the differential action is corrected in real time to effectively deal with the local curing defects caused by abnormal resin flow.

[0104] Embodiment 2

[0105] Based on the forming process of the carbon fiber composite rail transit component described in Embodiment 1, this embodiment discloses a mold system, including a base body, an upper cover and a microchannel unit. The base body is provided with a mold cavity, and the mold cavity has an accommodation space for prepreg and resin; the base body is provided with a vacuum pressure closed-loop module and a partition heating module; the upper cover plate is arranged on the base body, and the upper cover plate is provided with a valve for injecting resin; the microchannel unit is communicated with the valve, and the microchannel unit has a biomimetic leaf vein fractal structure.

[0106] Here, the microchannel design with the biomimetic leaf vein fractal structure can ensure uniform resin flow, reduce bubbles and improve material properties.

[0107] Furthermore, the biomimetic leaf vein structure includes a main channel, and a plurality of branch channels are communicated with the circumferential side of the main channel; the fractal dimension of the branch channels is 1.7-1.9, the diameter of the main channel is 1 mm, the diameter of the branch channels is 0.3 mm, and the spacing is 8 mm; the vacuum pressure closed-loop module includes a piezoelectric ceramic sensor and a high-speed solenoid valve, and the high-speed solenoid valve is communicated with the mold cavity, and vacuum is pumped through the high-pressure solenoid valve; the heating module includes a plurality of heaters, which are respectively installed on the mold; the base body is made of a nickel-based superalloy (Inconel 718), and a coating is provided on the surface of the base body, and the coating is a diamond-like carbon film (DLC, thickness 2 μm, friction coefficient <0.1).

[0108] In the biomimetic leaf vein microchannel: the fractal dimension is used to describe the hierarchical distribution, branch angle and density of the leaf vein-like branch network. For example, a high fractal dimension means denser branches and a more efficient mass transfer path, similar to how plant leaf veins achieve uniform distribution of water and nutrients through multi-level bifurcations.

[0109] Furthermore, a secondary branch channel is connected to the circumferential side of each branch channel, and an independent micro-valve is installed in the secondary branch channel; here, the independent micro-valve of the branch channel can be controlled according to the pressure during the transmission process.

[0110] Specifically, when the pressure in a certain secondary branch channel exceeds the set value, the upstream valve is closed and the adjacent branch valve is opened to guide the resin to diffuse to the low-pressure area.

[0111] Example 1: Forming of the side wall panel of a subway vehicle (size 2000×1500×5mm)

[0112] Product specifications

[0113] Dimensions: 2000mm×1500mm×5mm (flat plate structure);

[0114] Material system: T800SC carbon fiber / 5260 epoxy resin prepreg (curing window 80-130°C).

[0115] Details of process implementation:

[0116] Laminate preparation:

[0117] Laminate sequence: [0° / 45° / 90° / -45°]2 (n = 2), total number of layers 8;

[0118] Release film parameters: thickness 0.05mm, containing 5wt% SiO2 nanoparticles (particle size 50nm);

[0119] Pre-compaction: maintained at 0.5MPa for 3min, fiber volume content V f = 61%.

[0120] Multi-stage vacuum infusion:

[0121] Stage 1: Vacuum degree -0.095MPa, the mold is preheated to 60°C and kept at a constant temperature for 10min;

[0122] Stage 2: Increased to -0.1MPa, start 20kHz ultrasonic wave (power density 2W / cm 2 );

[0123] Stage 3: Decreased to -0.08Mpa at a rate of 0.02MPa / min;

[0124] Gradient curing control:

[0125] Temperature curve:

[0126] 60°C×30min (resin viscosity drops to 180cps);

[0127] 80 °C × 20 min (heating rate is triggered after the curing degree reaches 65% monitored by DSC);

[0128] 110 °C × 15 min (terminated after the volatile content reaches 0.08% detected by TGA);

[0129] Control algorithm: Fuzzy PID is used to adjust the heating rate to 2 °C / min (in the stage of 80 → 110 °C).

[0130] Mold system configuration:

[0131] Microchannel: The diameter of the main channel is 1 mm, the diameter of the branch channel is 0.3 mm, and the fractal dimension is 1.8;

[0132] Surface coating: DLC coating (thickness 2 μm, friction coefficient 0.08);

[0133] Verification results:

[0134] Porosity: 0.18% (detected by micro-CT scanning, ASTM D2734).

[0135] In the above embodiments, the descriptions of each embodiment have their own focuses. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0136] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A carbon fiber composite material rail transit component molding process, characterized in that: include: The carbon fiber layers are laid in an asymmetric quasi-isotropic order, and nano-modified release films are inserted between adjacent carbon fiber layers to form a prepreg layup and pre-compact it; The pre-compacted prepreg plies are placed into the mold and multi-stage vacuum coordinated resin infusion is performed; Heat the mold to solidify the resin and then cool it down for demoulding; During the heating process, the real-time curing degree is used to dynamically adjust the heating rate through an improved fuzzy PID algorithm.

2. The fiber composite material rail transit component molding process according to claim 1, characterized in that: The asymmetric quasi-isotropic sequence is [0° / 45° / 90° / -45°]n, where n=2-4.

3. The fiber composite material rail transit component molding process according to claim 1, characterized in that: The step of placing the pre-compacted prepreg layer into a mold and performing multi-stage vacuum coordinated resin infusion comprises: The pre-compacted prepreg layer is placed in a mold, the vacuum degree in the mold is adjusted to a first vacuum threshold, and the mold is preheated at a constant temperature at a first temperature threshold; The vacuum degree in the mold is adjusted to the secondary vacuum threshold, and the ultrasonic generator for improving the uniformity of resin flow is started; The vacuum degree in the mold is adjusted to the third-level vacuum threshold at a preset depressurization rate.

4. The fiber composite material rail transit component molding process according to claim 3, characterized in that: The first-level vacuum threshold is -0.093Mpa to -0.097Mpa, the second-level vacuum threshold is -0.098Mpa to -0.102Mpa, the third-level vacuum threshold is -0.078Mpa to -0.082Mpa, and the first temperature threshold is 58°C to 62°C.

5. The carbon fiber composite material rail transit component molding process according to claim 1, characterized in that: The method of dynamically adjusting the heating rate by using the improved fuzzy PID algorithm using the real-time curing degree includes: According to the real-time curing degree and the real-time dielectric loss factor, the curing degree deviation, the curing degree change rate and the abnormal fluctuation of the dielectric signal are calculated; Determine the control parameter adjustment amount based on the preset membership function and fuzzy matching rules for the curing degree deviation, the curing degree change rate and the abnormal fluctuation of the dielectric signal; Based on the control parameter adjustment amount, the heating power is controlled by the PID controller output to adjust the heating temperature; The membership function and the fuzzy matching rule are constructed in combination with the curing reaction kinetics characteristics of the resin.

6. The carbon fiber composite material rail transit component molding process according to claim 1, characterized in that: The thickness of the nano-modified release film is 0.03 mm to 0.07 mm.

7. The carbon fiber composite material rail transit component molding process according to claim 1, characterized in that: The resin is poured into the mold through a microfluidic unit, and the microfluidic unit is a bionic leaf vein fractal structure.

8. A mold system for the molding process of carbon fiber composite rail transit components according to any one of claims 1 to 7, characterized in that: include: A substrate, wherein the substrate is provided with a mold cavity, wherein the mold cavity has a space for accommodating prepreg layers and resin; the substrate is provided with a vacuum pressure closed-loop module and a zoned heating module; An upper cover, the upper cover plate is arranged on the base body, and the upper cover plate is provided with a valve for injecting resin; A microfluidic channel unit is connected to the valve, and the microfluidic channel unit has a bionic leaf vein fractal structure.

9. The mold system according to claim 8, characterized in that: The bionic leaf vein structure comprises a main channel, a plurality of branch channels are connected to the circumferential side of the main channel, and the fractal dimension of the branch channels is 1.7-1.

9.

10. The mold system according to claim 8, characterized in that The surface of the substrate is provided with a coating.

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