New energy FPC bending and attaching auxiliary material replacement method and FPC product

Abstract

The application belongs to the technical field of FPC manufacturing, and discloses a new energy FPC bending and attaching auxiliary material replacement method and an FPC product. The method comprises the following steps: attaching high-adhesion bubble cotton according to FPC bending and limiting etching lines; bending FPC according to the FPC bending and limiting etching lines to make the FPC adhere to the bubble cotton; using a semi-automatic pressing tool to press and hold the bending area; testing the product after bending according to the standard; after the operation is completed, picking up the product and putting it into a turnover box, and waiting for the next process. After the auxiliary material is replaced, the application is verified by gradient (500.1000.1500pcs), and the yield is 100%. No bubble cotton rebound and FPC pressing marks and other defects are found.

Description

Technical Field

[0001] This invention belongs to the field of FPC manufacturing technology, and particularly relates to a method for replacing auxiliary materials for bending and bonding of new energy FPCs and FPC products. Background Technology

[0002] Currently, the industry uses reinforcement, foam, and screw-fixing to fix the bending effect after bending FPC; including: reinforcement bonding of 2 pieces, reinforcement pressing, reinforcement curing, glue-free foam bonding, manual bending of FPC, fixing with 2 screws, and visual inspection; the existing technical process is long.

[0003] Based on the above analysis, the problems and defects of the existing technology are as follows: due to the characteristics of the product substrate FPC, the strong rebound force after bending exceeds the customer's acceptable standard; the demand for auxiliary materials is large, the efficiency is slow, and the time and manpower are consumed, resulting in a long delivery cycle. Summary of the Invention

[0004] To overcome the problems existing in related technologies, the present invention discloses an embodiment of a method for replacing auxiliary materials in the bending and bonding of new energy FPC and an FPC product, which is applied to FPC bending at 180°; it relates to a process for replacing auxiliary materials in the bending and bonding of new energy FPC.

[0005] The technical solution is as follows: a method for replacing auxiliary materials used in the bending and bonding of new energy FPCs, including the following steps: S1, high-viscosity foam is bonded according to the FPC bending limit etching line; S2, bend the FPC according to the FPC bending limit etching line to bond the FPC to the foam; S3 uses a semi-automatic pressing fixture to press and maintain pressure in the bending area; S4, Inspect the bent product according to the standard; S5. After the work is completed, put it into the turnover box for the next process.

[0006] In step S1, the bonding gap tolerance in the bonding high-viscosity foam is ≤ ±0.05mm, and the adhesive layer thickness is 25±5μm.

[0007] In step S3, the semi-automatic pressing fixture is used to press and hold pressure in the bending area. The hot pressing composite parameters include: Temperature gradient: 80℃ in the pre-compression stage, 150℃ in the main pressure stage, and 110℃ in the pressure holding stage, with segmented temperature control; Pressure curve: 0.5MPa in the pre-pressure stage, 1.2MPa in the main pressure stage, and 0.8MPa in the pressure holding stage; Time control: 30s for pre-pressure stage, 90s for main pressure stage, and 60s for cooling and shaping during pressure holding stage; The bending structure parameters include: dynamic bending radius ≥ 3T; Environmental adaptability parameters include: temperature cycling range: -40℃~125℃; humidity tolerance: 85%RH / 168h.

[0008] Furthermore, the control methods for semi-automatic pressing tooling include: S301, dynamic pressure adjustment; S302, geometry adaptation optimization; S303, Real-time stress monitoring.

[0009] In step S301, dynamic pressure adjustment includes: (i) Elasticity threshold locking mechanism: when , ; when , ; In the formula, The applied dynamic elastic force value, The rated elasticity threshold, Apply a spring force value to the locked state. Apply elasticity to the unlocked state. The elastic coefficient, For displacement, To unlock the coefficient of friction; (ii) Gradient magnetic field coordinated control: Non-uniform field strength model: ; In the formula, The gradient magnetic field is the coordinated value. Based on the fundamental magnetic field strength, These are the gradient coefficients. This represents the radial distance.

[0010] In step S302, the geometry adaptation optimization includes: (1) Multi-point support deflection algorithm: In the formula, The deflection angle of the tooling unit. The distance between the support rod and the curved surface. Let the length of the support rod be on the horizontal axis. Let the length of the support rod be on the vertical axis. Let the length of the support rod in space be denoted as . The x-coordinate of the reference point on the surface. The position of the ordinate of the reference point on the surface. The position of the reference point in space on the surface; (2) Adsorption and positioning through the air intake hole; Air pump negative pressure model: ; In the formula, This is the adsorption pressure value. For airflow rate, This represents the total area of ​​the air intake vents. Adsorption time; In step S303, real-time stress monitoring includes: (1) Linear feedback control model: In the formula, This is the predicted value of residual stress. For material constants, The critical strain. For strain amplitude, The number of bends; (2) Pulse energy modulation: In the formula, This represents the plasma pulse energy value. For power density, The pulse width. The repetition frequency.

[0011] In step S3, after pressing and holding the bending area using a semi-automatic pressing fixture, the pressed and bent area is further subjected to: plasma grafting treatment and magnetic field-assisted directional glue removal. The plasma grafting treatment includes: Step 1, Surface pretreatment; Gas composition: 70-80% argon, 20-30% nitrogen / oxygen; Power density: 0.5-5 W / cm³ 2 RF power supply 13.56MHz or microwave 2.45GHz; processing time: 30-180 seconds; vacuum degree: 10-100Pa, low-pressure environment ensures uniformity; Step 2, monomer grafting; Grafting monomers: AAc acrylate, MMA methyl methacrylate; Atomization parameters: nozzle spacing 0.5-3cm, atomization pressure 0.2-0.5MPa; Reaction temperature: room temperature to 80℃; Residence time: 20-60 minutes; Step 3, plasma-induced grafting; discharge mode: dielectric barrier discharge (DBD) or radio frequency plasma; energy input: pulse modulation, 60A / 5min, 75A / 12min, 85A / 10min; grafting layer thickness: 25±5μm; The magnetic field-assisted directional glue removal includes: Step (a), magnetic field generation and colloid preparation; magnetic field strength: 100-500mT; colloid composition: nano-ceramic / ferrite filler, particle size 3-5μm; filler ratio: 5-9wt%, magnetic filler coating non-magnetic substrate; Step (b): Directional adhesive removal and curing; Magnetic field direction: parallel / perpendicular to the substrate surface; Shear flow field: rate 10-50s. -1 Curing conditions: UV curing or heat curing; Step (c), performance verification.

[0012] In step S4, the bent product is inspected according to the standard. The predicted bending fatigue life is: In the formula, This is the predicted value for bending fatigue life. For material constants, For critical dependent variable, For the actual dependent variable, This represents the number of bends in a cycle; The interface peel strength check is as follows: In the formula, 90° peel strength The force applied for peeling, The width of the sample. This refers to the peeling length.

[0013] Furthermore, during the inspection of the bent product according to the standard, the thermal stress matching equation is: In the formula, This represents the difference in CTE between the FPC and auxiliary materials. The reaction time of thermal stress, The coefficient of thermal stress, This represents the yield strength of the adhesive layer.

[0014] Another objective of this invention is to provide a new energy FPC product, which is manufactured using the new energy FPC bending and bonding auxiliary material replacement method.

[0015] Combining all the above technical solutions, the beneficial effects of this invention are as follows: This invention, after optimizing and replacing auxiliary materials, achieved a 100% yield rate in tiered verification (500, 1000, 1500 pieces), with no defects such as foam rebound or FPC creases observed. It eliminates the cumbersome processes of applying reinforcements, pressing reinforcements, applying foam, and securing with screws, saving auxiliary materials (e.g., reinforcement 2, foam, screw 2) and improving product turnover (eliminating approximately 5 minutes for reinforcement application, 10 minutes for reinforcement pressing, 60 minutes for reinforcement curing, and 5 minutes for foam application and screw securing, totaling 80 minutes of savings), thus shortening delivery time. It also saves labor costs, calculated based on a requirement of one person per process. In existing technology, one person is needed per shift for bonding reinforcement, one person for pressing and curing reinforcement, and one person for applying foam, bending, and tightening screws, totaling 3 people per day. With the improvement of this invention, only one person is needed for applying foam and bending FPC, saving 2 people per shift. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the disclosure of the invention and, together with the description, serve to explain the principles of the disclosure. Figure 1 This is a flowchart of the method for replacing auxiliary materials for bending and bonding new energy FPCs provided in this embodiment of the invention; Figure 2 This is a prior art FPC diagram provided in the embodiments of the present invention before improvement; Figure 3 This is an improved FPC pattern manufactured according to the present invention, provided by an embodiment of the present invention. Detailed Implementation

[0017] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] Example 1: This invention uses high-adhesion foam (material code: 97120BJ*1.2mm, requires special customization) to replace the original process. One piece of high-adhesion foam can optimize and replace the cumbersome processes in the early stage, such as attaching reinforcement, pressing reinforcement, attaching foam, and fixing with screws, thereby saving auxiliary material costs and manpower input, and greatly shortening the delivery cycle.

[0019] like Figure 1 As shown, the replacement methods for bending and bonding auxiliary materials in new energy FPCs include: S1, high-viscosity foam is bonded according to the FPC bending limit etching line; S2, bend the FPC according to the FPC bending limit etching line to bond the FPC to the foam; S3 uses a semi-automatic pressing fixture to press and maintain pressure in the bending area; S4, Inspect the bent product according to the standard; S5. After the work is completed, put it into the turnover box for the next process.

[0020] For example, in step S1, when bonding high-viscosity foam, the bonding gap tolerance is ≤ ±0.05mm (laser positioning assistance); the adhesive layer thickness is 25±5μm (UV adhesive replaces traditional epoxy adhesive). In step S3, the hot-pressing composite parameters for pressing the bending area using a semi-automatic pressing fixture include: Temperature gradient: 80℃ in the pre-compression stage, 150℃ in the main pressure stage, and 110℃ in the pressure holding stage. Segmented temperature control is used to avoid thermal shock. Pressure curve: 0.5MPa in the pre-pressure stage, 1.2MPa in the main pressure stage, and 0.8MPa in the pressure holding stage; Time control: 30s for pre-pressure stage, 90s for main pressure stage, and 60s for cooling and shaping during pressure holding stage; Step S3 uses a semi-automatic pressing fixture to press the bending area. The bending structure parameters include: Dynamic bending radius: ≥3T (T is the total thickness of FPC, and ≥5T is required for new energy scenarios).

[0021] For example, in steps S1-S3, the environmental adaptability parameters include: Temperature cycling range: -40℃~125℃ (simulating extreme battery pack conditions); Humidity tolerance: 85%RH / 168h (designed to prevent electrolyte penetration).

[0022] For example, in step S3, a semi-automatic pressing fixture is used to press the bending area. The control method for pressing with the semi-automatic pressing fixture includes: S301, dynamic pressure adjustment; (i) Elasticity threshold locking mechanism: when , ; when , ; In the formula, The applied dynamic elastic force value, The rated elasticity threshold, Apply a spring force value to the locked state. Apply elasticity to the unlocked state. The elastic coefficient, For displacement, To unlock the friction coefficient; as shown by the above formula, by setting a preset elasticity threshold (e.g., 500N), the roller pressing mechanism is automatically locked when the pressure is not reached, ensuring uniform force distribution in the initial stage of pressing; it is automatically unlocked after reaching the threshold, avoiding overload damage to the material, and increasing the pressing pass rate to 95%; (ii) Gradient magnetic field coordinated control: Non-uniform field strength model: ; In the formula, The gradient magnetic field cooperative value, Based on the fundamental magnetic field strength, These are the gradient coefficients. The radial distance is given. The above formula shows that inducing magnetic fillers (such as nano-ferrites) to form a biomimetic brick-and-mortar structure improves fracture toughness to 2.8 times that of traditional processes and reduces internal stress by 40%.

[0023] S302, geometry adaptation optimization; (1) Multi-point support deflection algorithm: In the formula, The deflection angle of the tooling unit. The distance between the support rod and the curved surface. Let the length of the support rod be on the horizontal axis. Let the length of the support rod be on the vertical axis. Let the length of the support rod in spatial coordinates be denoted as . The x-coordinate of the reference point on the surface. The position of the ordinate of the reference point on the surface. The position of the reference point in space is given by the curvature. It can be seen that for thin-walled curvature parts, the bending area and the curved surface are adaptively fitted by calculating the deflection angle of the tooling module in segments, thereby reducing the pressing deformation deviation to within ±5%.

[0024] (2) Adsorption and positioning through the air intake hole; Air pump negative pressure model: ; In the formula, This is the adsorption pressure value. For airflow rate, This represents the total area of ​​the air intake vents. The adsorption time; in the FPC bending fixture, the flexible circuit board is fixed by negative pressure to avoid displacement during pressing and improve the interface bonding force by 30%.

[0025] In step S303, real-time stress monitoring includes: (1) Linear feedback control model: In the formula, This is the predicted value of residual stress. For material constants, The critical strain. For strain amplitude, The number of bends; based on the bending fatigue life formula, the pressure holding parameters are dynamically adjusted to increase the interface bonding strength from 8N / mm to 12N / mm (new energy standard).

[0026] (2) Pulse energy modulation: In the formula, This represents the plasma pulse energy value. For power density, The pulse width. The repetition frequency is set at [specific value]. Combined with online infrared monitoring, the plasma grafting depth is controlled to nanometer-level precision (25±5μm), reducing energy consumption to 27% of traditional processes. Application verification: FPC flexible circuits: Bending fixtures combined with pneumatic adsorption improve the yield rate to 98.5%.

[0027] For example, after pressing and holding the bending area using a semi-automatic pressing fixture in step S3, the pressed bending area is further subjected to: plasma grafting treatment (increasing the interface bonding force by 30%); and magnetic field-assisted directional glue removal (reducing internal stress by 40%). Specifically, plasma grafting treatment includes: Step 1, Surface pretreatment (activation stage); Gas composition: 70-80% argon, 20-30% nitrogen / oxygen; Power density: 0.5-5 W / cm³ 2 (RF power supply 13.56MHz or microwave 2.45GHz); Processing time: 30-180 seconds, preferably ≤60 seconds for ultra-thin materials; Vacuum degree: 10-100Pa, low-pressure environment ensures uniformity; This invention innovatively employs a segmented gas strategy (such as cleaning with argon first, followed by activation with nitrogen) to increase the surface energy to over 72 mN / m and reduce the contact angle to below 20°.

[0028] Step 2, Monomer Grafting (Functionalization Stage); Grafting Monomers: Acrylic acid (AAc), methyl methacrylate (MMA), etc.; Atomization Parameters: Dual nozzle spacing 0.5-3cm, atomization pressure 0.2-0.5MPa; Reaction Temperature: Room temperature to 80℃ (avoid heat damage); Residence Time: 20-60 minutes (preliminary polymerization is completed in the pre-reaction chamber); This invention innovatively proposes that atmospheric pressure atomization technology replaces the soaking method, increasing monomer utilization by 90% and reducing waste liquid.

[0029] Step 3, plasma-induced grafting; discharge mode: dielectric barrier discharge (DBD) or radio frequency plasma; energy input: pulse modulation (e.g., 60A / 5min→75A / 12min→85A / 10min); grafting layer thickness: 25±5μm; this invention innovatively proposes that pulse discharge controls the grafting depth, combined with online infrared monitoring, to achieve nanometer-level precision.

[0030] For example, magnetic field-assisted directional glue removal includes: Step (a), magnetic field generation and colloid preparation; magnetic field strength: 100-500mT (N35 grade neodymium magnet); colloid composition: nano-ceramic / ferrite filler (particle size 3-5μm); filler ratio: 5-9wt% (magnetic filler coating non-magnetic substrate); this invention innovatively proposes a gradient magnetic field design (such as non-uniform field strength) to induce the filler to form a biomimetic brick-mud structure, which improves the fracture toughness by 2.8 times.

[0031] Step (b): Directional adhesive removal and curing; Magnetic field direction: parallel / perpendicular to the substrate surface (adjusted according to stress requirements); Shear flow field: rate 10-50s. -1 (Collaborative magnetic field orientation); Curing conditions: UV curing (wavelength 365nm) or thermosetting (≤110℃); This invention innovatively proposes that magnetic field-shear flow field coupling enables the filler orientation to reach 95% and reduces internal stress by 40%.

[0032] Step (c), performance verification; test parameters: interfacial bonding energy: ≥120J / m 2 (After plasma grafting); Internal stress reduction: 40% (compared to non-magnetic field process); Wear resistance: Coating hardness reaches 2000 HV (e.g., TiN / Al2O3 composite layer). The effects of the above technical characteristics are shown in Table 1. Table 1 Comparison of Technical Features In step S4, the bent product is inspected according to the standard. The predicted bending fatigue life is: In the formula, This is the predicted value for bending fatigue life. For material constants, For critical dependent variable, For the actual dependent variable, This represents the number of bends in a cycle; The interface peel strength check is as follows: In the formula, 90° peel strength The force applied for peeling, The width of the sample. This refers to the peeling length.

[0033] During the inspection of the bent product according to the standard, the thermal stress matching equation is: In the formula, This represents the difference in CTE between the FPC and auxiliary materials. The reaction time of thermal stress, The coefficient of thermal stress, This represents the yield strength of the adhesive layer.

[0034] Test experiment: 1. Mechanical performance tests are shown in Table 2; Table 2 Mechanical Performance Test Table 2. Environmental reliability verification.

[0035] (1) Temperature and humidity cycling experiment. Conditions: -40℃ (30min), 85℃ / 85%RH (8h), 125℃ (30min); Cycle: Resistance change rate ≤5% after 500 cycles; (2) Chemical corrosion test; Immersion solution: simulated electrolyte (EC:DMC=1:1+1M LiPF6); Requirements: no stratification or bubbling after 168h; 3. Specific electrical performance testing; Insulation resistance: ≥10 Ω under DC 500V 12 Ω (GB / T 13555); Arc resistance: ≥180s (UL 746A); Impedance stability: ΔZ≤±10% at 10GHz high frequency; 4. Microstructure analysis; SEM / EDS interface observation: confirmed the absence of microcracks and element migration; DSC-TG thermal analysis: glass transition temperature (Tg) of the auxiliary material ≥ 130℃; X-ray tomography: 3D reconstructed adhesive layer porosity ≤ 0.5%. In summary, the advantages of this invention compared to existing technologies are shown in Table 3. Table 3 Comparison of the present invention with the prior art As can be seen from the above embodiments, the FPC of the present invention will not cause abnormalities such as whitening of the packaging, excessive creases, or bending rebound after bending, which is within the acceptable range for customers.

[0036] It shortens the process and delivery cycle, and reduces the input of auxiliary materials, manpower and production costs.

[0037] Example 2: The present invention provides a new energy FPC product, which is manufactured by a new energy FPC bending and bonding auxiliary material replacement method.

[0038] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention and within the spirit and principles of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for replacing auxiliary materials used in the bending and bonding of new energy FPCs, characterized in that, The method includes the following steps: S1, high-viscosity foam is bonded according to the FPC bending limit etching line; S2, bend the FPC according to the FPC bending limit etching line to bond the FPC to the foam; S3 uses a semi-automatic pressing fixture to press and maintain pressure in the bending area; S4, Inspect the bent product according to the standard; S5. After the work is completed, put it into the turnover box for the next process.

2. The method for replacing auxiliary materials for bending and bonding new energy FPCs according to claim 1, characterized in that, In step S1, the bonding gap tolerance in the bonding high-viscosity foam is ≤ ±0.05mm, and the adhesive layer thickness is 25±5μm.

3. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 1, characterized in that, In step S3, the semi-automatic pressing fixture is used to press and hold pressure in the bending area. The hot pressing composite parameters include: Temperature gradient: 80℃ in the pre-compression stage, 150℃ in the main pressure stage, and 110℃ in the pressure holding stage, with segmented temperature control; Pressure curve: 0.5MPa in the pre-pressure stage, 1.2MPa in the main pressure stage, and 0.8MPa in the pressure holding stage; Time control: 30s for pre-pressure stage, 90s for main pressure stage, and 60s for cooling and shaping during pressure holding stage; The bending structure parameters include: dynamic bending radius ≥ 3T; Environmental adaptability parameters include: temperature cycling range: -40℃~125℃; humidity tolerance: 85%RH / 168h.

4. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 3, characterized in that, The control methods for semi-automatic pressing fixtures include: S301, dynamic pressure adjustment; S302, geometry adaptation optimization; S303, Real-time stress monitoring.

5. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 4, characterized in that, In step S301, dynamic pressure adjustment includes: (i) Elasticity threshold locking mechanism: when , ; when , ; In the formula, The applied dynamic elastic force value, The rated elasticity threshold, Apply a spring force value to the locked state. Apply elasticity to the unlocked state. The elastic coefficient, For displacement, To unlock the coefficient of friction; (ii) Gradient magnetic field coordinated control: Non-uniform field strength model: ; In the formula, The gradient magnetic field cooperative value, Based on the fundamental magnetic field strength, These are the gradient coefficients. This represents the radial distance.

6. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 4, characterized in that, In step S302, the geometry adaptation optimization includes: (1) Multi-point support deflection algorithm: In the formula, The deflection angle of the tooling unit. The distance between the support rod and the curved surface. Let the length of the support rod be on the horizontal axis. Let the length of the support rod be on the vertical axis. Let the length of the support rod in spatial coordinates be denoted as . The x-coordinate of the reference point on the surface. The position of the ordinate of the reference point on the surface. The position of the reference point in space; (2) Adsorption and positioning through the air intake hole; Air pump negative pressure model: ; In the formula, This is the adsorption pressure value. For airflow rate, This represents the total area of ​​the air intake vents. Adsorption time; In step S303, real-time stress monitoring includes: (1) Linear feedback control model: In the formula, This is the predicted value of residual stress. For material constants, The critical strain. For strain amplitude, The number of bends; (2) Pulse energy modulation: In the formula, This represents the plasma pulse energy value. For power density, The pulse width. The repetition frequency.

7. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 1, characterized in that, In step S3, after pressing and holding the bending area using a semi-automatic pressing fixture, the pressed and bent area is further subjected to: plasma grafting treatment and magnetic field-assisted directional glue removal. The plasma grafting treatment includes: Step 1, Surface pretreatment; Gas composition: 70-80% argon, 20-30% nitrogen / oxygen; Power density: 0.5-5 W / cm³ 2 RF power supply 13.56MHz or microwave 2.45GHz; processing time: 30-180 seconds; vacuum degree: 10-100Pa, low-pressure environment ensures uniformity; Step 2, monomer grafting; Grafting monomers: AAc acrylate, MMA methyl methacrylate; Atomization parameters: nozzle spacing 0.5-3cm, atomization pressure 0.2-0.5MPa; Reaction temperature: room temperature to 80℃; Residence time: 20-60 minutes; Step 3, plasma-induced grafting; discharge mode: dielectric barrier discharge (DBD) or radio frequency plasma; energy input: pulse modulation, 60A / 5min, 75A / 12min, 85A / 10min; grafting layer thickness: 25±5μm; The magnetic field-assisted directional glue removal includes: Step (a), magnetic field generation and colloid preparation; magnetic field strength: 100-500mT; colloid composition: nano-ceramic / ferrite filler, particle size 3-5μm; filler ratio: 5-9wt%, magnetic filler coating non-magnetic substrate; Step (b): Directional adhesive removal and curing; Magnetic field direction: parallel / perpendicular to the substrate surface; Shear flow field: rate 10-50s. -1 Curing conditions: UV curing or heat curing; Step (c), performance verification.

8. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 1, characterized in that, In step S4, the bent product is inspected according to the standard. The predicted bending fatigue life is: In the formula, This is the predicted value for bending fatigue life. For material constants, For critical dependent variable, For the actual dependent variable, This represents the number of bends in a cycle; The interface peel strength check is as follows: In the formula, 90° peel strength The force applied for peeling, The width of the sample. This refers to the peeling length.

9. The method for replacing the bending and bonding auxiliary materials of new energy FPC according to claim 8, characterized in that, During the inspection of the bent product according to the standard, the thermal stress matching equation is: In the formula, This represents the difference in CTE between the FPC and auxiliary materials. The reaction time of thermal stress, The coefficient of thermal stress, This represents the yield strength of the adhesive layer.

10. A new energy FPC product, characterized in that, It is manufactured using the new energy FPC bending and bonding auxiliary material replacement method according to any one of claims 1-9.

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