Workpiece machining method and system based on liquid rubber coating integrated forming

Abstract

The invention discloses a workpiece machining method and system based on liquid rubber coating integrated forming, and belongs to the technical field of precision manufacturing. Comprising the following steps: constructing a chemical anchor layer with an active functional group; putting the pretreated material as an insert into a mold system, and injecting liquid silicone rubber; in the vulcanization process, the vulcanization reaction rate of the surface of the material is controlled to be lower than that of the central area of the cavity, so that the vulcanization conversion rate of the surface lags behind the central area, and active functional groups in the liquid silicone rubber are diffused to a chemical anchor point layer and covalent crosslinking occurs in the lagging period to form a cross-interface chemical bonding network; and finally cooling and demolding. The chemical anchor point layer is constructed on the surface of the material, and the interface hysteresis reaction in the vulcanization process is controlled, so that the covalent bonding of the liquid silicone rubber and the heterogeneous material on the molecular level is realized, the interface stress mismatch caused by physical assembly is eliminated, the interface bonding strength and the sealing reliability are remarkably improved, and the production process is simplified.

Description

Technical Field

[0001] This invention belongs to the field of precision manufacturing technology, specifically a workpiece processing method and system based on liquid coating integral molding. Background Technology

[0002] With the continuous evolution of precision manufacturing and the widespread application of high-performance elastomer materials, liquid silicone rubber (LSR) has become an indispensable key material in automotive electronics, medical devices, high-end consumer electronics, and aerospace due to its excellent thermal stability, superior biocompatibility, chemical inertness, and outstanding electrical insulation properties. In existing industrial production practices, the injection molding process for liquid silicone rubber has formed a relatively mature technical system. This system typically encompasses the entire process from the precise metering and static mixing of the A and B two-component raw materials, to their delivery to the injection unit via a pressurization system, injection into the preheated mold cavity under precise temperature control using cold runner technology, and finally, the completion of cross-linking and vulcanization under high temperature and high pressure. Specifically, in order to ensure the physical and chemical properties of the molded products, existing technologies place great emphasis on the accuracy of the formulation. Component A (containing the base rubber and crosslinking agent) and component B (containing the base rubber and platinum catalyst) are usually controlled within a very small error range by a high-precision gear pump or piston pump, and the runner system is used to maintain the runner temperature between 30°C and 50°C to prevent the rubber from prematurely curing before entering the mold cavity, thereby achieving efficient production without runner waste.

[0003] However, despite the high level of technological maturity demonstrated by existing LSR molding technology in manufacturing single-material silicone products, this traditional production model faces severe technological challenges as modern industrial products move towards miniaturization, high integration, and reliability under extreme conditions. Under the current technological paradigm, mold design and manufacturing logic is entirely focused on the geometry of the silicone product itself—"molding first, then assembling." This means that the silicone functional component and the rigid substrate it needs to bond to (such as plastic shells, metal structural parts, etc.) are completely decoupled in the production chain. After the silicone component is vulcanized, it must be fixed to the target material through subsequent secondary assembly processes, adhesive bonding, or mechanical fitting. This decoupled production logic not only significantly lengthens the process flow and increases labor and equipment costs, but more fundamentally, it introduces insurmountable technical contradictions at the principle level.

[0004] At its root, this "split-type" process leads to inherent defects in interfacial bonding and sealing reliability. First, the pre-molded silicone parts inevitably experience shrinkage stress and dimensional variations after demolding, while the rigid substrate also has tolerances during processing. When the two are physically assembled, the contact stress distribution at the microscopic level is extremely uneven, easily forming stress concentration areas or tiny gaps, which can induce sealing failure under pressure fluctuations, thermal cycling, or mechanical vibration. Second, fully vulcanized silicone rubber has extremely low surface energy and high chemical inertness, with its interfacial molecular chains in a relatively stable cross-linked state. If it is then bonded to the substrate with an adhesive, its interfacial wettability is poor, making it difficult to form strong chemical bonds. The connection is often maintained only by intermolecular forces or micromechanical interlocking, leading to a rapid decay of bonding strength under extreme environments (such as high humidity and heat, solvent immersion, or cyclic loading).

[0005] Furthermore, from the perspective of rheology and thermodynamics in precision molding, existing technologies fall short in handling the sealing requirements of complex, irregularly shaped structures. Since silicone parts and the substrate are manufactured separately, perfect adhesion at the interface cannot be guaranteed during assembly, especially when dealing with functional components with complex three-dimensional curved surfaces. Accumulated assembly errors directly impair the product's airtightness and waterproof rating. Moreover, the secondary assembly process itself introduces risks of contamination and deformation. For medical-grade or precision electronic components, excessive operational steps significantly increase the product's failure rate. While there are attempts at insert molding in existing technologies, they generally suffer from the following fundamental defects: First, the substrate is not specifically surface-activated and chemically modified, resulting in only physical interlocking rather than chemical bonding at the interface; second, the mold design does not incorporate the thermophysical properties of the substrate into the temperature control compensation system, leading to thermal stress concentration at the interface; third, the injection and vulcanization processes rely on empirical parameters and lack real-time control based on material constitutive equations and reaction kinetics, failing to guarantee the consistency of the interface reaction.

[0006] Therefore, how to break through the traditional mindset of "forming first and then assembling", and achieve deep integration of silicone elastomer and heterogeneous substrate at the molecular level and perfect fit at the geometric level during the forming stage, eliminate interfacial stress mismatch and simplify the process chain, has become a key challenge and a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to provide a workpiece processing method and system based on liquid overmolding, in order to solve the problems mentioned in the background art, where the liquid silicone rubber parts and the raw materials are decoupled in the production process, resulting in complex assembly process, low interface bonding strength, and sealing performance easily affected by dimensional tolerances.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A workpiece processing method based on liquid overmolding integral molding includes the following steps: Step S1: Pre-treat the surface of the material to be bonded, including surface activation treatment and interfacial chemical modification, to construct a chemical anchor layer with active functional groups on the surface to be bonded. Step S2: The pre-treated material is placed into the mold system as an insert, so that the surface of the material to be bonded and the mold surface together form a closed injection cavity. Step S3: Inject liquid silicone rubber into the injection cavity so that the liquid silicone rubber directly fills the bonding surface of the material. Step S4: During the vulcanization process of the filled liquid silicone rubber, the vulcanization reaction rate at the surface to be bonded is controlled to be lower than the vulcanization reaction rate in the central region of the injection cavity, so that the vulcanization reaction conversion rate at the surface to be bonded lags behind that in the central region. During the lag period, the active functional groups in the liquid silicone rubber diffuse to the chemical anchor layer and covalently cross-link with the chemical anchor layer to form a cross-interface chemical bonding network. Step S5: Cool and demold the vulcanized workpiece.

[0009] According to the above technical solution, the surface activation treatment adopts plasma treatment technology, which introduces polar functional groups on the surface of the material by bombarding it with high-energy particles, so that the surface energy of the material is raised to a level sufficient to form wetting and spreading with the coupling agent subsequently coated; the interface chemical modification is to coat the activated surface with a silane coupling agent. The molecular structure of the silane coupling agent contains a first active group and a second active group. The first active group is used to form a covalent bond with the polar functional groups on the surface of the material, and the second active group serves as a chemical anchor layer, which is used to undergo an addition reaction with the active functional groups of the liquid silicone rubber during the subsequent vulcanization process.

[0010] According to the above technical solution, the thickness of the coupling agent coating is determined based on the interfacial stress transfer theory. It is set to ensure that the coupling agent layer can completely cover the micro-defects on the surface of the material and form a continuous stress buffer layer at the interface, while ensuring that the cohesive strength of the coupling agent layer is not lower than the bonding strength between the liquid silicone rubber and the coupling agent interface.

[0011] According to the above technical solution, when the pre-processed material is placed into the mold system, visual positioning compensation technology is adopted: the coordinates of feature points on the surface of the material are collected, the deviation between the actual pose and the theoretical pose of the material is calculated based on the image processing algorithm, and the placement position of the material is compensated in real time according to the deviation, so that the fit gap between the material and the mold is less than the critical gap value at which liquid silicone rubber leaks under injection pressure.

[0012] According to the above technical solution, the mold system is provided with an elastic sealing compensation structure in the edge area that contacts the material. The elastic sealing compensation structure generates elastic deformation under the action of mold closing pressure, and applies a sealing pressure to the surface of the material. The sealing pressure is set according to Hertz contact theory to be a multiple of the peak value of the injection pressure of liquid silicone rubber, so as to ensure that the sealing interface is always in an elastic contact state within the range of mold closing force fluctuation.

[0013] According to the above technical solution, the injection process of liquid silicone rubber adopts a segmented injection control strategy: the first stage is to fill at high speed with a shear rate higher than the critical value of shear thinning of liquid silicone rubber, and use the shear thinning effect to reduce the viscosity of the rubber to achieve rapid mold filling; the second stage is to decelerate and penetrate at a shear rate lower than the critical value of shear thinning, so that the rubber penetrates into the micropores on the surface of the material at a low shear rate; the third stage is to hold pressure with a preset holding pressure to compensate for the volume shrinkage of the rubber in the subsequent vulcanization process.

[0014] According to the above technical solution, the control of the injection process is based on the rheological constitutive equation of liquid silicone rubber: in, For apparent viscosity, For temperature, Shear rate, It has zero shear viscosity and its relationship with temperature satisfies the WLF equation. This represents the critical shear stress at which the material enters the shear-thinning region. Non-Newtonian exponents; By monitoring the displacement and pressure of the injection screw in real time, the current shear rate and apparent viscosity are inferred, and the injection speed is dynamically adjusted according to the rheological constitutive equation, so that the filling process is always within the preset shear rate window.

[0015] According to the above technical solution, the specific method for controlling the vulcanization reaction rate at the surface to be bonded to be lower than that in the central region is as follows: adopting a zoned independent temperature control technology, applying differentiated heat power to different regions of the injection cavity, so that the temperature at the surface to be bonded is lower than that in the central region, forming a temperature gradient window, and utilizing the influence of temperature on the vulcanization reaction rate, so that the vulcanization reaction conversion rate at the surface to be bonded lags behind that in the central region. The lag time is determined based on the diffusion coefficient of the active functional groups in liquid silicone rubber and the equivalent diffusion distance of the chemical anchor layer, and is set to meet the diffusion-reaction coupling condition.

[0016] According to the above technical solution, the control of the vulcanization process is based on the Kamal-Sourour reaction kinetics model: in, The conversion rate of the sulfidation reaction, , The reaction rate constant is given and obeys the Arrhenius equation. , This is the reaction order parameter; Temperature distribution data is obtained by embedding multiple thermocouples at the mold cavity and the material bonding surface. Based on the reaction kinetic model, the heating power of the partition is dynamically adjusted so that the vulcanization process proceeds according to the preset conversion rate curve, and the concentration of active functional groups of the rubber material at the interface is maintained higher than that in the center area of ​​the cavity during the lag period.

[0017] A workpiece processing system based on liquid overmolding integral molding, the system comprising: The surface treatment and coating subsystem is used to perform plasma activation treatment and coupling agent coating on the surfaces of the materials to be bonded, so as to construct a chemical anchor layer on the surface of the materials. The integrated mold unit includes a fixed mold, a moving mold, a mold temperature control component, and a material positioning mechanism. The material positioning mechanism fixes the material in a preset position, so that the surface of the material to be bonded and the mold surface together form the physical boundary of the closed injection cavity. The mold temperature control component adopts a regional independent temperature control architecture, which can apply differentiated heat power to different areas of the injection cavity. The raw material storage and metering unit is used to store liquid silicone rubber raw materials of components A and B and output them precisely according to a preset ratio. The mixing and injection execution unit, connected to the raw material storage and metering unit, is used to inject the mixed adhesive into the injection cavity; The central control and real-time monitoring system is connected to the surface treatment and coating subsystem, the integrated mold unit, the raw material storage and metering unit, and the mixing and injection execution unit. The central control and real-time monitoring system integrates a rheological control module and a vulcanization control module. The rheological control module has a fixed rheological constitutive equation for liquid silicone rubber, which is used to dynamically correct the injection speed curve based on the real-time feedback injection parameters. The vulcanization control module has a fixed vulcanization reaction kinetic model, which is used to dynamically adjust the zone heating power based on real-time temperature data to achieve differentiated vulcanization control between the surface to be bonded and the central area.

[0018] Compared with the prior art, the present invention has the following beneficial effects: First, by incorporating the raw material as part of the molding system into the molding process, this invention breaks the logical separation between "molding and assembly" in traditional processes, achieving deep integration of silicone elastomers and rigid materials at the thermal, mechanical, and chemical levels. Second, through the synergistic effect of plasma activation and coupling agent pretreatment, cross-interface covalent bonding is induced during the one-piece molding process, resulting in a peel strength between silicone and the raw material that significantly exceeds the tear strength of the silicone material itself, greatly improving the structural stability and environmental durability of the product. Furthermore, the closed-loop control strategy based on rheological and dynamic models employed in this invention effectively solves the problems of uneven filling and thermal stress concentration in complex irregular cavities, ensuring processing accuracy and sealing reliability. In summary, this invention, through systematic process reconstruction and precise control, significantly simplifies the production chain, eliminates secondary assembly errors, and provides an efficient and highly reliable technical solution for the manufacturing of high-performance multi-material composite workpieces. Attached Figure Description

[0019] Figure 1 This is a flowchart of the workpiece processing method of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1 like Figure 1 As shown, the present invention provides a workpiece processing method based on liquid overmolding. Its core concept is to integrate the material to be bonded as a high-precision insert into the mold system, and to construct an active reaction layer on the surface of the material through surface pretreatment, so that the liquid silicone rubber can directly complete the phase change process from liquid rheology to solid crosslinking on the surface of the material, thereby establishing a cross-interface covalent bonding network at the molecular level and eliminating the interfacial stress mismatch caused by physical assembly.

[0022] The workpiece processing method based on liquid coating integral molding provided by this invention first pre-treats the surfaces of the materials to be bonded. This pre-treatment includes two progressive steps: surface activation treatment and interface chemical modification. The surface activation treatment employs atmospheric pressure room temperature plasma jet technology, with the plasma power supply frequency set to 20kHz to 40kHz and the discharge power to 500W to 800W, using compressed air as the working gas. During plasma generation, a high-frequency, high-voltage electric field ionizes gas molecules, generating a plasma beam containing a large number of high-energy electrons, ions, and active free radicals (such as ·O and ·OH). According to plasma sheath theory, under typical operating conditions of 600W discharge power and 30kHz frequency, the plasma density can reach 10¹. 6 The energy distribution is on the order of m⁻³, with peak ion energy distribution ranging from 2 eV to 5 eV. High-energy particles physically bombard and chemically modify the material surface: physical bombardment removes the weak boundary layer through momentum transfer; this weak boundary layer is typically a layer of organic contaminants and oxides with a thickness of 10 nm to 100 nm. Chemical modification introduces polar functional groups such as hydroxyl (-OH) and carboxyl (-COOH) groups through the reaction of active free radicals with molecules on the material surface. After this treatment, the water contact angle of the material surface is reduced to below 30°, and the surface energy is increased from below 30 mN / m initially to above 45 mN / m, providing an excellent wettability foundation for subsequent coating layers.

[0023] After surface activation, a silane coupling agent modified layer is coated onto the surface to be bonded, with the coating thickness controlled to be 5 μm to 15 μm. The silane coupling agent used has the general molecular formula YR-SiX3, where X is a hydrolyzable group (such as methoxy or ethoxy), and Y is an active functional group (such as vinyl or silane-hydrogen group) that can undergo addition reactions with liquid silicone rubber. This coupling agent forms a self-assembled monolayer or multilayer structure on the material surface: the X group is hydrolyzed under the action of air moisture or residual hydroxyl groups on the surface to generate silanol groups (Si-OH), which then condense with hydroxyl groups on the material surface to form covalent bonds (Si-OM, where M represents atoms on the material surface); the Y group is exposed on the surface, serving as a "chemical anchor" for subsequent vulcanization reactions. The selection of coupling agent layer thickness is based on the theory of interfacial stress transfer: when the thickness is less than 5 μm, it is difficult to completely cover surface micro-defects (typical roughness Ra is 0.4 μm to 1.6 μm) and the chemical anchor density is insufficient; when the thickness is greater than 15 μm, the cohesive strength of the coupling agent layer itself becomes the weak link at the interface, and the failure mode will change from interfacial debonding to cohesive failure of the coupling agent layer. Uniform coating is achieved by using an ultrasonic spraying device with atomized particle size controlled between 20 μm and 50 μm and a spraying path scanning interval of 5 mm, ensuring that the coating thickness deviation is controlled within ±2 μm.

[0024] After pretreatment, the mold components are integrated and precisely positioned. The pretreated material is precisely placed into the positioning base of the mold system, which includes a fixed mold, a moving mold, a positioning base, and the interface to be formed from the material. The positioning base adopts a composite structure of vacuum adsorption and mechanical clamping, achieving a positioning accuracy of ±0.01mm. In the mold-closed state, the inner cavity surface of the moving mold and the surface of the material to be bonded together form a closed injection cavity. To prevent liquid silicone rubber from leaking from the bonding surface between the material and the mold under injection pressure (i.e., "flash"), the mold system has an elastic sealing compensation structure in the edge area in contact with the material. This structure uses an O-ring or rectangular sealing strip made of high-temperature resistant fluororubber (operating temperature range -20℃ to 250℃), with its compression deformation controlled between 15% and 25%. Under the action of mold closing pressure, the sealing structure undergoes elastic deformation, applying a uniform sealing pressure to the surface of the material. According to Hertzian contact theory, the sealing specific pressure must meet the following requirements. ≥ 1.5 × ,in To maximize injection pressure, the sealing interface is kept in an elastic contact state rather than a plastic yield state within the range of mold clamping force fluctuations, thus forming a physical barrier to prevent flash from occurring in the liquid silicone rubber during the injection stage.

[0025] In the material preparation stage, precise metering and mixing of liquid silicone rubber raw materials are performed. This process uses a two-component addition-curing liquid silicone rubber, including component A containing vinyl-terminated polydimethylsiloxane and a platinum catalyst, and component B containing a hydrogen-containing silicone oil crosslinking agent. Components A and B are delivered to the static mixer in a 1:1 volume ratio using a high-precision synchronous metering pump. To ensure consistent physical properties after molding, the raw material storage and transportation unit is equipped with a follow-up pressure plate, and a vacuum degassing device reduces the pressure inside the raw material tank to below -0.09 MPa for at least 30 minutes. According to Henry's Law, the solubility of a gas in a liquid is directly proportional to pressure. The vacuum environment brings the equilibrium concentration of dissolved gases and microbubbles close to zero, thereby forcibly removing air bubbles from the rubber compound. The static mixer is equipped with staggered spiral mixing units, forcing the fluid to continuously cut, shift, and overlap during flow, ensuring a mixing uniformity deviation of less than 0.1%. The mixed rubber compound enters the cold runner system, where the temperature is maintained at 35°C to 45°C by the circulating cooling medium inside the cold runner, ensuring good fluidity and preventing premature vulcanization.

[0026] The mixed liquid rubber compound is driven by the injection mechanism into a programmed segmented injection process. The injection control unit executes a three-stage injection control strategy based on real-time feedback from the cavity pressure sensor. This invention's injection control is based on the rheological constitutive equation of liquid silicone rubber, which is a pseudoplastic fluid with an apparent viscosity... With shear rate and temperature The relationship follows a modified Cross-WLF model: in, The zero-shear viscosity, in relation to temperature, satisfies the WLF equation, as shown below: in, The reference temperature (usually the glass transition temperature) ), , For addition-cure liquid silicone rubber, where is a material constant. The typical value is 17.4. It is 51.6K; The critical shear stress for the material to enter the shear-thinning region is obtained by rheometer testing, with a typical range of 1000 Pa to 5000 Pa. It is a non-Newtonian exponent (0 < n < 1), reflecting the degree of shear thinning, with typical values ​​ranging from 0.2 to 0.5.

[0027] Based on the above model, the injection control unit calculates the volumetric flow rate by real-time monitoring of the injection screw displacement. ) and pressure (calculating injection pressure) ), and inversely calculate the current shear rate ( (flow channel radius) and apparent viscosity .

[0028] The rheological basis of the three-stage injection strategy is: The first stage is the high-speed filling period, with a shear rate of... Set to 1000s -1 up to 3000s -1 By utilizing the shear thinning effect, the viscosity of the rubber compound is reduced to 10% to 30% of the zero shear viscosity, enabling rapid filling and preventing surface defects caused by cooling at the fluid front. The second stage is the deceleration penetration period, during which the shear rate decreases to 100 s. -1 up to 300s -1 This allows the adhesive to penetrate the micropores (average pore size 1μm to 10μm) of the material surface at a low shear rate, achieving deep wetting. This stage follows the capillary penetration equation as shown below: in For penetration depth, Where is the pore radius, For the surface tension of the rubber compound, Contact angle, For time; The third stage is the high-pressure holding period, where the holding pressure is set to 70% to 85% of the injection pressure and the holding time is 5 to 15 seconds. This is used to compensate for the volume shrinkage of the rubber compound during the subsequent vulcanization process (the volume shrinkage rate of addition-cured LSR is usually 2% to 3%).

[0029] After injection molding, in-situ thermal vulcanization and interfacial bonding control are performed. The mold heating system raises the cavity wall temperature to 160°C to 180°C, and the heat is transferred to the rubber compound via conduction. The vulcanization reaction is a platinum-catalyzed addition reaction: vinyl-terminated polydimethylsiloxane (Vi-PDMS) and hydrogen-containing silicone oil (Si-H) undergo hydrosilylation under the action of a platinum catalyst to form a cross-linked network. The vulcanization control of this invention is based on the Kamal-Sourour reaction kinetic model, which can accurately describe the conversion rate of the addition vulcanization reaction. Changes over time: in, The conversion rate of the sulfidation reaction (0 to 1) was obtained by online monitoring of the exothermic integral of the reaction using differential scanning calorimetry (DSC). , Let be the reaction rate constant, which obeys the Arrhenius equation: in, Pre-exponential factor, As the activation energy, for a typical addition-type LSR, Approximately 50 kJ / mol to 70 kJ / mol (initial reaction). Approximately 40 kJ / mol to 60 kJ / mol (autocatalytic reaction); , The reaction order parameter reflects the reaction mechanism. It is usually between 2 and 3.

[0030] Based on the above model, the control system acquires temperature distribution data through multiple thermocouples embedded at the mold cavity and the material interface, and dynamically adjusts the zoned heating power. A key technical feature is that the control system actively establishes and maintains a temperature gradient window, ensuring that the vulcanization rate of the rubber at the material interface is slightly lower than that in the center of the cavity. Specifically, by adjusting the heating power, the temperature at the interface is... Temperature at the center of the cavity The difference in vulcanization reaction rate caused by a temperature decrease of 3°C to 8°C affects the conversion rate of the rubber compound at the interface. Lag cavity center conversion rate Approximately 3 to 5 seconds. The chemical mechanism of this delayed vulcanization strategy is as follows: During the hysteresis window, the rubber compound at the interface maintains a low viscosity, allowing sufficient time for its active functional groups (vinyl groups) to diffuse into the silane coupling agent layer; the vinyl groups diffused to the interface covalently crosslink with the exposed Y groups of the coupling agent under the action of a platinum catalyst, forming a Si-CH2-CH2-Si interfacial chemical bond; when the cavity center is completely vulcanized and forms a dense network, the covalent bonding at the interface is also completed simultaneously, thus achieving a molecular stitching effect. Hysteresis time The selection must satisfy the diffusion-reaction coupling condition. ,in The effective thickness of the coupling agent layer (equivalent diffusion distance) is given. The diffusion coefficient of active functional groups in the rubber compound (approximately 10⁻) 9 m² / s up to 10⁻ 8 (on the order of m² / s), calculations yield... The requirement is 1 to 10 seconds, which matches the 3 to 5 seconds set in this invention.

[0031] Once the vulcanization degree reaches 95% or higher (confirmed by DSC signal or preset time), cooling and demolding are performed. Heating is stopped and the circulating cooling circuit is activated, reducing the workpiece temperature to below 50℃ at a cooling rate of 30℃ / min to 50℃ / min. Controlling the cooling rate is to prevent thermal expansion differences between the silicone rubber and the substrate (silicone rubber CTE is approximately 200 × 10⁻⁶). -6 / K to 300×10 -6 / K, the CTE of aluminum alloy is approximately 23×10 -6 The thermal stress generated by / K exceeds the interfacial bonding strength. According to thermoelasticity theory, the interfacial thermal stress is as follows: in For elastic modulus, The coefficient of thermal expansion, subscript and These represent the raw material and silicone rubber, respectively. This represents the temperature change. By controlling the cooling rate, thermal stress is slowly released within the material's yield strength range, preventing the formation of microcracks at the interface. Subsequently, the mold closing mechanism is opened, and the ejection system removes the workpiece, which has been integrally bonded to the material, as a whole.

[0032] This invention also provides a workpiece processing system based on liquid overmolding integral molding. The system includes a raw material storage and metering unit, a mixing and injection execution unit, an integrated mold unit, a surface treatment and coating subsystem, and a central control and real-time monitoring system. The raw material storage and metering unit stores A and B components of liquid silicone rubber raw material and precisely outputs them according to a preset ratio. This unit includes two feeding tanks equipped with follow-up pressure plates and a precision gear pump driven by a servo motor. The single-revolution displacement accuracy of the gear pump reaches 0.01 ml. The mixing and injection execution unit is connected to the raw material storage and metering unit and includes a static mixing pipe, a cold runner manifold, and an injection head. The injection head is equipped with a closed-loop controlled hydraulic or electric motor drive device, capable of providing an injection pressure of up to 20 MPa and supporting multi-stage injection speed switching. The integrated mold unit includes a fixed mold template, a moving mold template, a mold temperature control component, and a material positioning mechanism. The material positioning mechanism uses vacuum adsorption or precision mechanical clamping to fix the material at a preset geometric coordinate position, so that the surface of the material to be bonded and the mold surface together form the physical boundary of the closed injection cavity. The surface treatment and coating subsystem is located at the front end of the mold unit and includes a plasma treatment head, a six-axis industrial robot, and an ultrasonic spraying device. It is used to activate the material surface and coat it with coupling agent before the workpiece enters the mold.

[0033] The mold temperature control system employs a zoned independent temperature control architecture. Three-dimensional conformal heating pipes are arranged inside the fixed and moving molds, and each temperature control zone is equipped with an independent PID control loop and a solid-state relay. The zoned independent temperature control system divides the mold into at least three independent temperature control zones: the cavity center zone, the material contact zone, and the sealing edge zone. Each zone is equipped with an independent thermocouple, PID controller, and a composite temperature control unit consisting of an electric heating rod and cooling pipes. The control system has a built-in database of material thermophysical properties, automatically calling upon the specific heat capacity of the material based on its material composition (metal, plastic, or ceramic). Thermal conductivity Thermal diffusivity ( (for density), and based on the Fourier heat conduction equation and one-dimensional transient heat conduction model It calculates and compensates for local temperature deviations caused by heat absorption or dissipation of the materials in real time, ensuring that the temperature uniformity in the injection cavity is controlled within ±1℃.

[0034] The central control and real-time monitoring system uses an industrial-grade programmable logic controller (PLC) as its core, connecting pressure sensors, thermocouples, displacement sensors, and servo drives via a bus architecture. The system integrates a rheology control module, a vulcanization control module, and a vision positioning compensation module. The rheology control module embeds the aforementioned Cross-WLF model and parameter database, dynamically adjusting the injection speed curve based on real-time feedback of injection pressure, screw displacement, and compound temperature to ensure the filling process remains within a preset shear rate window. The vulcanization control module embeds the Kamal-Sourour kinetic model, calculating the current conversion rate based on real-time temperature data. The system predicts the time required to reach the target conversion rate. When the predicted vulcanization endpoint deviates from the actual monitored value by more than 5%, it automatically adjusts the heating power for the remaining vulcanization time. Before the material is placed into the mold, the visual positioning compensation module captures the coordinates of feature points (at least 3 non-collinear feature points) on the surface of the material using a high-resolution industrial camera (resolution ≥ 5MP). Based on Hough transform or contour matching algorithms, it calculates the deviation between the actual pose and the theoretical pose of the material. , , The system sends compensation instructions to the six-axis industrial robot to achieve a placement accuracy of ±0.02mm, eliminating the risk of flash from the source.

[0035] The injection unit's cold runner system employs a needle valve nozzle structure. The opening and closing of the needle valve is driven by a pneumatic or hydraulic actuator and logically correlated with the injection stroke. During the holding pressure phase after the injection cycle, the needle valve precisely seals the injection port, preventing heat from the high-temperature mold cavity from flowing back to the runner system. This ensures that the rubber compound within the runner remains in an uncured liquid state, enabling continuous, waste-free production. The raw material storage and metering unit also integrates a vacuum degassing device. Before components A and B enter the metering pump, the pressure inside the raw material tank is reduced to below -0.09 MPa by the vacuum pump and maintained for at least 30 minutes. This removes micro-air bubbles entrained during mixing and transport, ensuring that the molded silicone parts have a dense internal structure and excellent dielectric properties.

[0036] Example 2 In the implementation of the workpiece processing method and system based on liquid coating integral molding provided by the present invention, a detailed description is given using 6061 aluminum alloy material (size 50mm×30mm×5mm, surface roughness Ra=0.8μm) and addition-cured liquid silicone rubber with a hardness of Shore A 50 as an example.

[0037] First, the surfaces of the materials to be bonded undergo precise pretreatment, which is fundamental to building a high-performance interface. In the surface activation stage, atmospheric pressure room-temperature plasma jet technology is employed. The plasma treatment head uses 30kHz high-frequency, high-voltage energy generated by a plasma power source to ionize compressed air, forming a low-temperature plasma beam. Driven by a 600W discharge power, the high-energy electrons, ions, and active free radicals such as ·O and ·OH contained in the plasma beam physically bombard and chemically modify the material surface. According to plasma sheath theory, the plasma density at these parameters is approximately 10-1. 16 m -3 The peak ion energy distribution ranges from 2 eV to 5 eV, sufficient to break C-C bonds (bond energy 348 kJ / mol) and CH bonds (bond energy 413 kJ / mol) and introduce oxygen-containing functional groups without causing excessive sputtering to the aluminum substrate. A six-axis industrial robot carrying a plasma treatment head passes uniformly across the material surface at a scanning speed of 100 mm / s, strictly maintaining a vertical distance of 5 mm to 10 mm between the nozzle and the surface. Detection using a contact angle tester shows that the water contact angle on the activated material surface decreased from the initial 65° to 25°, and the surface energy increased from 28 mN / m to 52 mN / m.

[0038] After surface activation, interfacial chemical modification is performed. A silane coupling agent modified layer is uniformly coated onto the activated surfaces to be bonded using an ultrasonic spraying device. This embodiment uses... -Methacryloxypropyltrimethoxysilane (KH-570) has a methoxy group as the first active group and a methacryloxy group as the second active group in its molecular structure. The coating thickness is controlled at 10 μm. This thickness is selected based on Fick's second law: when the adsorption rate and desorption rate of silane molecules on the activated surface are in equilibrium, the self-assembled monolayer thickness is approximately 2 nm to 5 nm. However, in order to compensate for the surface micro-roughness (Ra = 0.8 μm) and form a continuous stress buffer layer, a coating thickness of 10 μm is required. Uniform coverage is achieved by using ultrasonic spraying with atomized particle size (controlled between 20 μm and 50 μm) and a spraying path (scanning spacing of 5 mm). The coating thickness deviation is ±1.8 μm as measured by an ellipsometrometer.

[0039] The pre-processed material is fed into the integrated mold unit. During this process, the central control and real-time monitoring system uses an industrial camera (5MP resolution) to capture the coordinates of three feature points on the surface of the material. The visual processing algorithm calculates the sub-pixel level coordinates of the center of the feature points based on the Hough transform and performs least-squares fitting with the theoretical pose to obtain the actual pose deviation. , , The six-axis industrial robot compensates for this deviation in real time, precisely placing the material into the positioning base inside the fixed mold. The positioning base uses a composite structure of vacuum adsorption (vacuum degree -0.08MPa) and mechanical clamping to achieve a placement accuracy of ±0.008mm. After the moving mold and fixed mold are closed, the surface of the material to be bonded directly serves as a physical wall of the injection cavity. To prevent leakage of liquid silicone rubber under injection pressure, the mold system has an elastic sealing compensation structure at the edge of the material. The rectangular sealing strip is made of high-temperature resistant fluororubber (operating temperature range -20℃ to 250℃, hardness Shore A 70), with an initial thickness of 2mm and compression deformation controlled at 20%. Under the action of the mold closing pressure (150kN), the sealing structure undergoes elastic deformation. The sealing specific pressure applied to the surface of the material is tested to be 18MPa, while the maximum injection pressure is 12MPa. The sealing specific pressure is 1.5 times the injection pressure, meeting the sealing requirements.

[0040] In the material preparation stage, the raw material storage and metering unit precisely mixes the two-component liquid silicone rubber. Component A contains vinyl-terminated polydimethylsiloxane (vinyl content 0.2 mmol / g) and a platinum catalyst (platinum content 2000 ppm), while Component B contains a hydrogen-containing silicone oil crosslinking agent (Si-H content 0.4 mmol / g). Both feeding tanks are equipped with follow-up pressure plates, and a vacuum degassing device continuously degasses the raw materials at a vacuum degree of -0.095 MPa for 30 minutes to eliminate microbubbles. A servo motor-driven precision gear pump presses components A and B into a static mixer at a 1:1 ratio with a step accuracy of 0.01 ml. The static mixer contains 12 staggered spiral mixing units that repeatedly cut and reassemble the rubber compound. Infrared spectroscopy analysis shows that the mixing uniformity deviation between the two components is 0.06%. The mixed rubber compound enters the cold runner system, where the circulating cooling medium (constant temperature water) maintains its temperature at 40°C, ensuring good fluidity and preventing premature vulcanization.

[0041] Entering the programmed segmented injection process stage, the injection control unit executes a rheological compensation control strategy based on the Cross-WLF model. The rheological parameters of the LSR in this embodiment were obtained by testing at 40°C using a rotating rheometer (plate-to-plate mode, 0.5 mm gap): zero shear viscosity. WLF reference temperature (LSR's) ), , Critical shear stress Non-Newtonian exponents Injection control logic: The first injection speed is set to 40 cm³ / s, corresponding to the flow channel radius. The shear rate below At this point, the viscosity drops to The filling time is 1.2s; when the pressure sensor detects that the leading edge of the adhesive has reached the edge of the material, the system enters the second stage, and the injection speed is reduced to 8cm³ / s. The viscosity rises to approximately 1800 Pa·s, with a penetration time of 2 s, ensuring that the rubber compound fully penetrates the micropores on the surface of the material; then it enters the high-pressure holding period, with a holding pressure of 12 MPa (77.4% of the injection pressure of 15.5 MPa) and a holding time of 10 s, to compensate for the curing shrinkage of the rubber compound.

[0042] In-situ thermal vulcanization is a crucial step in achieving intermolecular bonding. The mold temperature control system utilizes three-dimensional conformal heating pipes arranged inside the mold to rapidly raise the cavity wall temperature to 170°C. In this embodiment, the Kamal-Sourour kinetic parameters—activation energy—were obtained through non-isothermal DSC testing (heating rates of 5K / min, 10K / min, and 20K / min) combined with Kissinger's method fitting. , Pre-exponential factor , Reaction order , The control system collects temperature distribution data in real time using three thermocouples embedded at the center of the mold cavity, the material interface, and the sealing edge. During the initial heating phase, the heating rate detected by the thermocouples at the material interface is approximately 2°C / s slower than at the cavity center. When the cavity center reaches 170°C, the material interface is approximately 165°C. Based on this, the control system dynamically adjusts the heating power compensation in the material contact area, ensuring the interface temperature reaches 170°C within 15 seconds, creating a temperature lag window of approximately 5 seconds. During this lag window, the conversion rate of the adhesive at the interface... Lagging cavity center Approximately 4.2 seconds (obtained from online model calculations) are required for the active functional groups to fully diffuse into the coupling agent layer and undergo covalent cross-linking. The total vulcanization time is 90 seconds, with the conversion rate predicted by the model. The time required to reach 0.98 has been determined.

[0043] To verify the interfacial bonding mechanism, elemental analysis of the interfacial layer was performed using X-ray photoelectron spectroscopy (XPS). The results showed that an Al-O-Si bond binding energy signal (approximately 102 eV) was detected at the interface between the silicone rubber and the aluminum alloy, confirming the chemical bonding between the silane coupling agent and the aluminum matrix; simultaneously, a Si-CH2-CH2-Si bond signal (approximately 283.5 eV) was detected, confirming the addition reaction between the silicone rubber and the Y group of the coupling agent. The calculated covalent bond density at the interface was approximately [value missing]. It is far higher than the interfacial interaction energy that can be achieved by physical adsorption.

[0044] Once the vulcanization degree reaches 95% or higher (confirmed by DSC signal monitoring), the system automatically switches to the cooling cycle. The workpiece temperature is reduced from 170℃ to 50℃ at a cooling rate of 40℃ / min, with the cooling process lasting 3 minutes. By controlling the cooling rate, the interfacial thermal stress is slowly released within the range of the aluminum alloy yield strength (approximately 280MPa) and the silicone rubber tear strength (approximately 40N / mm). Thermal stress simulation verification shows that the maximum interfacial thermal stress is approximately 12MPa, which is lower than the interfacial bonding strength.

[0045] Subsequently, the ejection system removes the integrated structure consisting of the material and the silicone rubber overlay from the positioning base. At this point, the overlay and the material have formed a chemically integrated structure.

[0046] To verify the technical effect of the present invention, a comparative test was conducted using a comparative example. The comparative example used the same aluminum alloy material and liquid silicone rubber, but instead of plasma activation and coupling agent pretreatment, it underwent traditional solvent cleaning (acetone wiping) and physical roughening (120-grit sandpaper polishing). After the silicone rubber parts were individually injection molded, they were then manually assembled with commercially available RTV silicone adhesive and cured at room temperature for 24 hours.

[0047] Performance tests were conducted on the workpieces prepared in the examples and comparative examples. The interfacial peel strength was tested according to ISO 813 standard using a universal testing machine at a peel speed of 50 mm / min for a 180° peel test. The peel strength of the example was 12.5 N / mm, with the failure mode being silicone rubber body tearing; the peel strength of the comparative example was 2.8 N / mm, with the failure mode being interfacial debonding. For airtightness testing, compressed air was used as the test medium, with the pressure gradually increased from 0.1 MPa until leakage occurred. The upper limit of the airtightness pressure for the example was 0.85 MPa (reaching the material's own pressure limit), while leakage occurred at the interface in the comparative example at 0.12 MPa. High and low temperature cycling durability testing was conducted for 100 cycles within a temperature range of -40℃ to 150℃ (30 min at each temperature point, with a 5 min temperature transition time). After the test, the peel strength reduction rate for the example was 4.2%, and for the comparative example, it was 45.8%. In terms of the total processing cycle, the example is 125s (automated continuous production), while the comparative example exceeds 86,400s (including 24 hours of curing time).

[0048] The process window for key parameters was validated through Design of Experiments (DOE). With a coupling agent thickness ranging from 5 μm to 15 μm, the peel strength was greater than 10 N / mm; when the thickness decreased to 3 μm, the peel strength dropped to 6.2 N / mm (interfacial debonding); and when the thickness increased to 20 μm, the peel strength dropped to 7.5 N / mm (cohesive failure of the coupling agent layer). With a hysteresis time ranging from 3 s to 5 s, the interfacial covalent bond density was greater than [missing value]. When the hysteresis time is less than 2 seconds, the interfacial bond density decreases to The peel strength decreased to 8.1 N / mm; when the hysteresis time was greater than 7 s, over-vulcanization in the central region led to an increase in residual stress at the interface, and the peel strength decreased to 9.2 N / mm. The first shear rate was 1000 s. -1 up to 3000s -2 Within the specified range, the filling is complete and there are no filling defects; below 800s -1 Short shots occur; above 3500s -1 Jet marks and localized overheating degradation were observed (infrared thermal imaging showed that the local temperature exceeded 180°C).

[0049] This system was also validated on plastic materials (PBT+30%GF) and ceramic materials (alumina). For PBT materials, the plasma treatment power was reduced to 400W to prevent surface overheating and degradation, and the coupling agent was changed to aminosilane (KH-550), whose amino groups can react with the ester groups of PBT. Test results showed that the interfacial peel strength reached 8.6 N / mm, and the failure mode was silicone rubber bulk tearing. For alumina ceramic materials, using the same treatment parameters as aluminum alloys, the interfacial peel strength reached 10.2 N / mm, and the failure mode was also silicone rubber bulk tearing.

[0050] During system operation, the central control and real-time monitoring system communicates at high speed with various sensors and drivers via EtherCAT bus (communication cycle 1ms). Pressure sensors are embedded in the runner near the end of the cavity; the pressure waveforms they capture in real time are used to correct the switching point for the next injection cycle. Displacement sensors precisely monitor the ejection mechanism's stroke (accuracy ±0.01mm), ensuring uniform force on the workpiece during demolding. A machine vision-based positioning compensation module collects material feature points before each cycle; its positioning compensation algorithm calculates pose deviation based on least squares fitting, with a compensation response time of less than 200ms, ensuring consistent placement accuracy. The mold temperature control component uses parameters from the material's thermophysical property database (aluminum alloy: , , PBT: , , Automatically adjusts and compensates for heat flow to ensure that the temperature uniformity of the dispensing cavity is controlled within ±1℃ under different material conditions.

[0051] In summary, this invention successfully solves the long-standing technical challenge of interface reliability in hard-soft composite parts through a systematic innovation in processing methods—from atomic-level surface activation (physicochemical mechanisms and parameter control of plasma treatment), molecular-level interfacial bonding (bifunctional group design and diffusion-reaction coupling mechanism of silane coupling agents), to system-level in-situ forming (high-precision insert positioning, elastic sealing compensation, and regional thermal compensation) and rheology-reaction coupling control (implementable closed-loop control based on Cross-WLF and Kamal-Sourour models). This invention not only achieves a generational leap in physical performance compared to traditional processes (interfacial peel strength increased by more than 4 times, and airtightness and pressure resistance increased by more than 7 times), but also fundamentally improves production efficiency, yield control, and process stability through system integration and model-driven control, demonstrating outstanding substantive features and significant progress.

[0052] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are 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 process, method, article, or apparatus.

[0053] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A workpiece processing method based on liquid coating integral molding, characterized in that: Includes the following steps: Step S1: Pre-treat the surface of the material to be bonded, including surface activation treatment and interfacial chemical modification, to construct a chemical anchor layer with active functional groups on the surface to be bonded. Step S2: The pre-treated material is placed into the mold system as an insert, so that the surface of the material to be bonded and the mold surface together form a closed injection cavity. Step S3: Inject liquid silicone rubber into the injection cavity so that the liquid silicone rubber directly fills the bonding surface of the material. Step S4: During the vulcanization process of the filled liquid silicone rubber, the vulcanization reaction rate at the surface to be bonded is controlled to be lower than the vulcanization reaction rate in the central region of the injection cavity, so that the vulcanization reaction conversion rate at the surface to be bonded lags behind that in the central region. During the lag period, the active functional groups in the liquid silicone rubber diffuse to the chemical anchor layer and covalently cross-link with the chemical anchor layer to form a cross-interface chemical bonding network. Step S5: Cool and demold the vulcanized workpiece.

2. The workpiece processing method based on liquid coating integral molding according to claim 1, characterized in that: The surface activation treatment employs plasma treatment technology, which introduces polar functional groups onto the material surface through high-energy particle bombardment, raising the surface energy to a level sufficient to wet and spread with the subsequently coated coupling agent. The interface chemical modification involves coating the activated surface with a silane coupling agent. The molecular structure of the silane coupling agent contains a first active group and a second active group. The first active group is used to form covalent bonds with the polar functional groups on the material surface, while the second active group serves as a chemical anchor layer, used to undergo an addition reaction with the active functional groups of the liquid silicone rubber during the subsequent vulcanization process.

3. The workpiece processing method based on liquid coating integral molding according to claim 2, characterized in that: The thickness of the coupling agent coating is determined based on the theory of interfacial stress transfer. It is set to ensure that the coupling agent layer can completely cover the micro-defects on the surface of the material and form a continuous stress buffer layer at the interface, while ensuring that the cohesive strength of the coupling agent layer is not lower than the bonding strength between the liquid silicone rubber and the coupling agent interface.

4. The workpiece processing method based on liquid coating integral molding according to claim 1, characterized in that: When the pre-processed material is placed into the mold system, visual positioning compensation technology is used: the coordinates of feature points on the surface of the material are collected, the deviation between the actual pose and the theoretical pose of the material is calculated based on the image processing algorithm, and the placement position of the material is compensated in real time according to the deviation, so that the gap between the material and the mold is less than the critical gap value at which liquid silicone rubber leaks under injection pressure.

5. The workpiece processing method based on liquid coating integral molding according to claim 1, characterized in that: The mold system has an elastic sealing compensation structure in the edge area that contacts the material. The elastic sealing compensation structure generates elastic deformation under the action of mold closing pressure, and applies a sealing pressure to the surface of the material. The sealing pressure is set according to Hertz contact theory to be a multiple of the peak value of the injection pressure of liquid silicone rubber, so as to ensure that the sealing interface is always in an elastic contact state within the range of mold closing force fluctuation.

6. The workpiece processing method based on liquid coating integral molding according to claim 1, characterized in that: The injection process of liquid silicone rubber adopts a segmented injection control strategy: the first stage is to fill at high speed with a shear rate higher than the critical value of shear thinning of liquid silicone rubber, and use the shear thinning effect to reduce the viscosity of the rubber to achieve rapid mold filling; the second stage is to decelerate the penetration with a shear rate lower than the critical value of shear thinning, so that the rubber can penetrate into the micropores on the surface of the material at a low shear rate; the third stage is to hold pressure with a preset holding pressure to compensate for the volume shrinkage of the rubber during the subsequent vulcanization process.

7. The workpiece processing method based on liquid coating integral molding according to claim 1, characterized in that: The injection process is controlled based on the rheological constitutive equations of liquid silicone rubber: in, For apparent viscosity, For temperature, For shear rate, It has zero shear viscosity and its relationship with temperature satisfies the WLF equation. This represents the critical shear stress at which the material enters the shear-thinning region. Non-Newtonian exponents; By monitoring the displacement and pressure of the injection screw in real time, the current shear rate and apparent viscosity are inferred, and the injection speed is dynamically adjusted according to the rheological constitutive equation, so that the filling process is always within the preset shear rate window.

8. The workpiece processing method and system based on liquid coating integral molding according to claim 1, characterized in that: The specific method for controlling the vulcanization reaction rate at the bonding surface to be lower than that in the central region is as follows: adopting zoned independent temperature control technology, applying differentiated heat power to different regions of the injection cavity, so that the temperature at the bonding surface is lower than that in the central region, forming a temperature gradient window. Utilizing the influence of temperature on the vulcanization reaction rate, the vulcanization reaction conversion rate at the bonding surface lags behind that in the central region. The lag time is determined based on the diffusion coefficient of active functional groups in liquid silicone rubber and the equivalent diffusion distance of the chemical anchor layer, and is set to satisfy the diffusion-reaction coupling condition.

9. A workpiece processing method and system based on liquid coating integral molding according to claim 8, characterized in that: The control of the vulcanization process is based on the Kamal-Sourour reaction kinetics model: in, The conversion rate of the sulfidation reaction, , The reaction rate constant is given and obeys the Arrhenius equation. , This is the reaction order parameter; Temperature distribution data is obtained by embedding multiple thermocouples at the mold cavity and the material bonding surface. Based on the reaction kinetic model, the heating power of the partition is dynamically adjusted so that the vulcanization process proceeds according to the preset conversion rate curve, and the concentration of active functional groups of the rubber material at the interface is maintained higher than that in the center area of ​​the cavity during the lag period.

10. A workpiece processing system based on liquid overmolding, used to perform the method according to any one of claims 1 to 9, characterized in that, The system includes: The surface treatment and coating subsystem is used to perform plasma activation treatment and coupling agent coating on the surfaces of the materials to be bonded, so as to construct a chemical anchor layer on the surface of the materials. The integrated mold unit includes a fixed mold, a moving mold, a mold temperature control component, and a material positioning mechanism. The material positioning mechanism fixes the material in a preset position, so that the surface of the material to be bonded and the mold surface together form the physical boundary of the closed injection cavity. The mold temperature control component adopts a regional independent temperature control architecture, which can apply differentiated heat power to different areas of the injection cavity. The raw material storage and metering unit is used to store liquid silicone rubber raw materials of components A and B and output them precisely according to a preset ratio. The mixing and injection execution unit, connected to the raw material storage and metering unit, is used to inject the mixed adhesive into the injection cavity; The central control and real-time monitoring system is connected to the surface treatment and coating subsystem, the integrated mold unit, the raw material storage and metering unit, and the mixing and injection execution unit. The central control and real-time monitoring system integrates a rheological control module and a vulcanization control module. The rheological control module has a fixed rheological constitutive equation for liquid silicone rubber, which is used to dynamically correct the injection speed curve based on the real-time feedback injection parameters. The vulcanization control module has a fixed vulcanization reaction kinetic model, which is used to dynamically adjust the zone heating power based on real-time temperature data to achieve differentiated vulcanization control between the surface to be bonded and the central area.

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