Epoxy resin mold based on three-dimensional photocuring molding technology and preparation method

Abstract

The invention discloses an epoxy resin mold based on a three-dimensional light curing molding technology and a preparation method, and particularly relates to the technical field of mold core molds for casting. The invention relates to an epoxy resin mold based on a three-dimensional photocuring molding technology. The epoxy resin mold is formed by compounding a three-dimensional photocuring molding piece and an epoxy resin-based filler. The invention discloses a preparation method of an epoxy resin mold based on a three-dimensional photocuring molding technology. The preparation method comprises the following steps: (1) preparing a photosensitive resin model with a cavity structure through the three-dimensional photocuring molding technology; and (2) preparing the epoxy resin-based filler. And (3) carrying out vacuum defoaming treatment on the epoxy resin-based filler, and then pouring the epoxy resin-based filler into a cavity of the photosensitive resin model. By means of the innovative process, the mold performance is improved, the service life of the prepared aggregate-containing epoxy resin mold can be remarkably prolonged, the mold replacement frequency can be reduced, the production efficiency can be improved, and considerable economic benefits can be brought to enterprises by means of the excellent strength and wear resistance of the aggregate-containing epoxy resin mold.

Description

Technical Field

[0001] The invention belongs to the technical field of core molds for casting, and particularly relates to an epoxy resin mold based on stereolithography molding technology and a preparation method thereof. Background Art

[0002] In the field of casting production, molds are the core elements that determine product molding accuracy and production efficiency, and their technological evolution has always been the focus of attention in the manufacturing industry. The traditional metal mold manufacturing system is based on metal materials such as steel and aluminum, and relies on processes such as CNC machining, casting and electric spark machining to build a molding system. With its high hardness, high temperature resistance and long service life, it has become a pillar technology for the production of large-scale, high-precision products such as automotive parts and aerospace structural parts. However, as the manufacturing industry transforms towards personalized customization and rapid iteration, the technical bottlenecks of traditional metal molds are becoming increasingly prominent: 1. Lengthy process chains lead to delayed response: Complex structure molds require multiple processes including rough machining, precision milling, heat treatment, and surface polishing. The typical production cycle for automotive panel molds can take 2-3 months, making it difficult to meet the demand for rapid mold testing in sectors such as consumer electronics and medical devices. 2. Cost thresholds restrict small-batch production: Metal raw material costs account for 20%-30%, and coupled with the investment in high-end equipment such as five-axis machining centers (a single unit costs over 10 million yuan), the manufacturing cost of a single mold remains high. In small-batch production, the mold cost per unit can be 5-8 times that of large-scale production. 3. Structural processing limits are difficult to break: For features such as the complex cooling cavities inside aircraft engine blades and the micro-flow channels of microelectronic devices, traditional cutting processing is limited by tool accessibility, and the efficiency of EDM decreases exponentially with structural complexity, resulting in severe constraints on design freedom.

[0003] The rise of 3D printing technology has provided a new dimension for paradigm shifts in mold manufacturing. Stereolithography (SLA), based on the principle of layer-by-layer photopolymerization, uses ultraviolet light to trigger the rapid cross-linking of liquid photosensitive resins, demonstrating significant advantages: Extremely fast molding capabilities: Complex parts that traditionally take weeks can be completed in a matter of hours. Full-dimensional molding freedom: Leveraging upgraded technologies like digital light processing (DLP), microstructure molding with 50μm resolution is possible, breaking through traditional machining restrictions on features like undercuts and interconnected holes. Green manufacturing attributes: Material utilization rates can exceed 95%, reducing material waste by over 70% compared to traditional cutting processes, in line with the needs of a circular economy.

[0004] However, the current engineering application of stereolithography in the mold field is limited by the bottleneck of the material system: mainstream acrylic resins have three major performance shortcomings: ① Uncontrolled chemical shrinkage: The free radical polymerization mechanism causes an 8%-15% volume shrinkage during the curing process, leading to mold dimensional deviation (typical error of 0.3-0.8mm) and internal stress concentration; ② Shortcomings in mechanical properties: The tensile strength is generally lower than 50MPa, and the flexural modulus is less than 2GPa. Plastic deformation is prone to occur during pressure molding. In a trial case of an injection mold, the service life is only 1 / 20 of that of a metal mold. ③ Thermal stability defects: The glass transition temperature (Tg) is mostly lower than 80°C, and softening failure occurs in medium-temperature process scenarios such as casting and hot pressing.

[0005] In recent years, researchers have explored the modification of resin-based composites. By introducing epoxy-acrylate hybrid systems, shrinkage has been reduced to 3%-5%, and the addition of nano-ceramic fillers (such as SiO2 and Al2O3) has increased the modulus to 3-4 GPa. However, new challenges remain, such as poor filler dispersion and loss of molding precision. The key scientific challenge in achieving breakthroughs in SLA mold engineering applications is to develop a new photocuring system with high strength, low shrinkage, and high temperature resistance while maintaining print fluidity. Summary of the Invention

[0006] The purpose of the present invention is to provide an epoxy resin mold based on stereolithography technology and a preparation method thereof.

[0007] In order to achieve the above object, the present invention provides the following technical solutions: An epoxy resin mold based on stereolithography technology, the epoxy resin mold comprising a stereolithography molded part and an epoxy resin-based filler; the stereolithography molded part is a photosensitive resin model prepared by stereolithography technology, and the photosensitive resin model has a preset cavity structure; The epoxy resin-based filler comprises the following components: epoxy resin, epoxy resin curing agent, aggregate, diluent, defoaming agent and silane coupling agent, wherein the diluent is 16-hexanediol diglycidyl ether, and its addition amount is 1-10% of the mass of the epoxy resin.

[0008] A method for preparing an epoxy resin mold based on stereolithography technology comprises the following steps: (1) Prepare a photosensitive resin model with a cavity structure by stereolithography technology. The thickness of the molding layer is 0.05mm-0.15mm and the UV light power is 80mW / cm 2 -120mW / cm 2 ; (2) Preparation of epoxy resin-based filler: Add epoxy resin, diluent, and defoamer to the container in sequence at 25-35°C, and stir at 200-500 rpm for 10-30 minutes; then add aggregate, silane coupling agent, and epoxy resin curing agent in batches while continuing to stir, controlling the stirring temperature to not exceed 40°C, to form a uniformly mixed epoxy resin-based filler; (3) After vacuum degassing, the epoxy resin-based filler is poured into the cavity of the photosensitive resin model at a pouring pressure of 0.2 MPa-0.8 MPa; the filler is allowed to stand and cure at 20°C-25°C for 24 hours-72 hours, or at 40°C-60°C for 2 hours to obtain a composite structure epoxy resin mold based on stereolithography technology.

[0009] Furthermore, the cavity structure of the photosensitive resin model in step (1) includes an injection channel and an exhaust channel that are interconnected, the injection channel has a diameter of 2-5 mm, and the exhaust channel has a diameter of 1 / 3-1 / 2 of the injection channel diameter.

[0010] Furthermore, the defoaming agent is a silicone defoaming agent, and its addition amount is 0.1%-2% of the mass of the epoxy resin; the aggregate is selected from one or more of corundum powder, glass fiber, silica powder, and titanium dioxide with a particle size of 200 mesh to 800 mesh, and its addition amount is 20%-80% of the mass of the epoxy resin; the silane coupling agent is a KH-550 or KH-602 type coupling agent, and its addition amount is 0.1%-2% of the mass of the epoxy resin.

[0011] Furthermore, the epoxy resin curing agent is an amine curing agent or an acid anhydride curing agent, and its addition amount is 30%-60% of the mass of the epoxy resin; the vacuum degassing treatment conditions in the step (3) are: vacuum degree -0.08MPa~-0.1MPa, and degassing time is 5 minutes to 15 minutes.

[0012] Furthermore, the epoxy resin mold based on the stereolithography molding technology can withstand a temperature of 80° C.-120° C. when used for wax injection molding, and can withstand a pressure of 0.5 MPa-2 MPa when used for the sand casting process.

[0013] Beneficial effects of the present invention: 1. Innovative Process Improves Mold Performance. This invention utilizes stereolithography 3D printing technology and innovatively infuses epoxy resin-based fillers into the molded part cavity, successfully producing epoxy resin molds with superior performance. This unique preparation method overcomes the limitations of traditional mold manufacturing processes, effectively combining the flexibility of 3D printing with the excellent properties of epoxy resin. Compared to traditional metal mold manufacturing processes, it avoids multiple complex steps and significantly shortens the mold manufacturing cycle.

[0014] 2. Diluents optimize processability. Adding 1,6-hexanediol diglycidyl ether as a diluent to epoxy resin-based fillers has a positive impact on the entire preparation process. 1,6-hexanediol diglycidyl ether can effectively reduce the viscosity of epoxy resin, giving it better fluidity during the infusion process. This not only helps the epoxy resin-based filler to be evenly filled into the cavity of the molded part, ensuring the integrity and consistency of the internal structure of the mold, but also greatly improves the convenience of process operations. For example, in the preparation of some molds with complex internal cavity structures, low-viscosity epoxy resin-based fillers can flow more smoothly into every corner, avoiding the problem of insufficient filling or gaps due to high viscosity, thereby improving the yield of the mold and reducing production costs.

[0015] 3. Defoamers improve surface quality. The defoamers used in this invention play a key role in improving mold surface quality. During the epoxy resin curing process, bubbles are easily generated due to various factors. If these bubbles are not promptly addressed, they will remain on the mold surface or inside, seriously affecting the overall quality of the mold. Defoamers can reduce the surface tension of the epoxy resin, causing bubbles to rupture quickly or accelerating their escape, significantly improving mold quality and yield rate.

[0016] 4. Aggregates enhance mold durability. By adding aggregates to epoxy resin-based fillers, the strength and wear resistance of the epoxy resin after curing are significantly improved. Aggregates, as a reinforcing material, are evenly distributed in the epoxy resin matrix, playing the role of skeleton support, and effectively enhancing the overall structural strength of the mold. In actual production applications, the mold needs to withstand various external forces and friction. The epoxy resin mold with the addition of aggregates can better resist these external forces and reduce the occurrence of wear and damage. The aggregate-containing epoxy resin mold prepared by the present invention can significantly extend the service life of the mold, reduce the frequency of mold replacement, improve production efficiency, and bring considerable economic benefits to the enterprise by virtue of its excellent strength and wear resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an epoxy resin wax injection mold a based on stereolithography technology.

[0018] Figure 2 It is an epoxy resin wax injection mold b based on stereolithography technology.

[0019] Figure 3 It is an epoxy resin wax injection mold c based on stereolithography technology.

[0020] Figure 4 This is a three-dimensional design drawing of an epoxy resin mold based on stereolithography technology.

[0021] Figure 5 This is a three-dimensional design drawing b of an epoxy resin mold based on stereolithography technology.

[0022] Figure 6 This is a three-dimensional design diagram of an epoxy resin mold based on stereolithography technology c. DETAILED DESCRIPTION

[0023] The preparation method of the present invention will be described in detail below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0024] Example 1 1. Preparation of photosensitive resin model This example uses stereolithography (SLA) technology to print the model. During the printing process, the layer thickness is controlled to 0.05mm to ensure that the model has a fine structure in the vertical direction. At the same time, the UV light power is set to 120mW / cm 2 This power can effectively trigger the curing reaction of photosensitive resin, ensuring that each layer of resin can be cured and formed evenly and quickly.

[0025] In terms of model design, a cavity structure with specific dimensions was constructed. The injection channel diameter was set at 20mm, and the exhaust channel diameter was 10mm, with the exhaust channel diameter being half the injection channel diameter. This cavity structure facilitates the subsequent injection of epoxy resin-based filler and the exhaust of gas during the infusion process, preventing defects such as bubbles from forming inside the mold, thereby ensuring mold quality.

[0026] 2. Preparation of epoxy resin-based fillers Epoxy resin is used as the base material in an amount of 1000g, which provides basic mechanical properties and bonding effects for the entire filler system.

[0027] 16-Hexanediol diglycidyl ether was used as the diluent, at a dosage of 10g, representing 1% of the epoxy resin mass. The diluent effectively reduces the viscosity of the epoxy resin and improves the fluidity of the filler, allowing it to evenly fill every corner of the model cavity during the infusion process.

[0028] Adding 1g (0.1%) of silicone defoamer can reduce the surface tension of epoxy resin, promote bubble bursting or accelerate bubble escape, reduce the generation of bubbles inside the mold, and improve the surface quality of the mold after curing.

[0029] The aggregate used is 100g of corundum powder (200 mesh) and 100g of glass fiber, accounting for 20% of the total. Corundum powder has high hardness and wear resistance, while glass fiber enhances the toughness of the material. The synergistic effect of the two improves the strength and wear resistance of the epoxy resin after curing.

[0030] Adding 10g (1%) of silane coupling agent (KH-550) can form a chemical bond between the aggregate and the epoxy resin, enhance the interfacial bonding between the aggregate and the matrix, and further improve the overall performance of the mold.

[0031] The amount of epoxy resin curing agent (amine) is 500g, accounting for 50%, which undergoes a cross-linking reaction with the epoxy resin, causing the filler to change from liquid to solid, forming a mold with certain strength and stability.

[0032] Preparation process: First, add epoxy resin, diluent, and defoamer to a container in sequence at 25°C, then stir at 300 rpm for 20 minutes. This process allows the diluent and defoamer to fully mix with the epoxy resin and evenly disperse in the system, exerting their viscosity-reducing and defoaming effects.

[0033] Next, add the aggregate, coupling agent, and curing agent in batches. During this addition process, strictly control the temperature to ≤40°C. Excessively high temperatures may cause the curing agent to react prematurely, affecting the filler's performance. Continue stirring until the entire system is homogeneous, ensuring that all components are thoroughly mixed, providing a good foundation for the subsequent molding and curing processes.

[0034] 3. Vacuum degassing and infusion The prepared mixture is placed in a vacuum of -0.09 MPa for degassing for 10 minutes. In a vacuum environment, the pressure on the bubbles in the mixture is reduced, and their volume expands and gradually escapes, effectively reducing the bubble content and further improving the quality of the filling material.

[0035] After degassing, the filler is poured into the mold cavity at a pressure of 0.5MPa. Appropriate pouring pressure can ensure that the filler is quickly and evenly filled in the mold cavity, ensuring the molding quality of the mold.

[0036] Curing Conditions: After infusion, the mold is left at 25°C for 48 hours to allow the epoxy resin to fully cure. Under these temperature and time conditions, the epoxy resin and curing agent can fully cross-link, forming a stable three-dimensional network structure, which gives the mold excellent mechanical properties.

[0037] 4. Performance Testing Wax Injection Molding Temperature Resistance: Tests have shown that the mold can withstand temperatures of 120°C without deformation during the wax injection molding process. This demonstrates that the mold has good dimensional stability in high-temperature environments and can meet the high-temperature resistance requirements of the wax injection molding process.

[0038] Pressure resistance during the foundry process: During the foundry process, the mold can withstand a pressure of 2MPa without cracking. This indicates that the mold has high compressive strength and can withstand the pressure of the sand mold during the foundry process, ensuring the smooth progress of the foundry process.

[0039] Tensile strength: The tensile strength of the mold measured by professional testing equipment is 137MPa, indicating that the mold has good ability to resist damage under tensile load.

[0040] Dimensional accuracy: The dimensional accuracy of the mold reaches IT7 level, which reflects the precise control of the mold size throughout the entire preparation process and can meet the use requirements of high-precision molds.

[0041] Example 2 1. Photosensitive resin model In this embodiment, the SLA printing parameters were adjusted appropriately. The layer thickness was set to 0.075 mm, which was slightly increased compared to Example 1. This improved the printing efficiency to a certain extent, while also having little effect on the overall structural accuracy of the model. The UV light power was adjusted to 100 mW / cm 2 , which can not only ensure the curing effect of photosensitive resin, but also adapt to the changes in energy demand caused by changes in layer thickness.

[0042] In the cavity structure design of the model, the diameter of the injection channel is increased to 50mm, and the diameter of the exhaust channel is 20mm, with a ratio of 1:2.5. This adjustment is based on the different characteristics of the filler and the requirements of the infusion process, ensuring smoother injection of the filler and smooth exhaust of the gas.

[0043] 2. Filler formula Epoxy resin is still used as the base material, and the dosage remains unchanged at 1000g.

[0044] The amount of diluent (16-hexanediol diglycidyl ether) was increased to 50g, accounting for 5% of the epoxy resin mass. This appropriate increase in diluent further improved the fluidity of the filler to accommodate changes in injection channel diameter and higher infusion requirements.

[0045] The dosage of the silicone defoamer is 10g, accounting for 1%, which continues to play its role in reducing surface tension and eliminating bubbles to ensure the surface quality of the mold.

[0046] 500g of silica micropowder (800 mesh) is used as aggregate, accounting for 50%. Silica micropowder has good filling properties and chemical stability, which can improve the density and stability of the mold.

[0047] The silane coupling agent used was KH-602, with a dosage of 20g, accounting for 2%. Different types of silane coupling agents may have better compatibility with silica powder, further enhancing the bonding strength between the aggregate and the epoxy resin matrix.

[0048] The anhydride curing agent dosage is 400g, accounting for 40%. The reaction characteristics of anhydride curing agents with epoxy resin are different from those of amine curing agents. By adjusting the type and dosage of curing agent, the curing process and final performance of the mold can be optimized.

[0049] 3. Process Stir at an ambient temperature of 35°C to fully mix the components. A higher temperature helps the diluent to work better, reduces the viscosity of the filler, and also speeds up the mixing speed between the components.

[0050] During vacuum degassing, increase the vacuum degree to -0.1MPa and extend the degassing time to 15 minutes. Adjustments to the filler formula may result in changes in the amount of bubbles generated. A higher vacuum degree and longer degassing time can more effectively remove bubbles and ensure the quality of the filler.

[0051] The injection pressure is increased to 0.8 MPa to ensure that the filling material can be quickly and evenly filled into the model cavity when the diameter of the injection channel is increased.

[0052] Curing: The curing process is to heat at 60°C for 4 hours. Properly increasing the curing temperature and shortening the curing time can accelerate the reaction speed of the epoxy resin and the acid anhydride curing agent, thereby improving production efficiency while ensuring mold performance.

[0053] 4. Performance Temperature tolerance: In the wax injection process, the mold can withstand a temperature of 110°C, which is slightly lower than that in Example 1, but can still meet the temperature requirements of general wax injection processes.

[0054] Pressure resistance: Under the sand casting process, the mold can withstand a pressure of 1.8MPa, which reflects the good pressure resistance of the mold.

[0055] Tensile strength: After testing, the tensile strength of the mold reached 155 MPa, which was higher than that of Example 1, indicating that the adjusted formula and process had a positive effect on the tensile properties of the mold.

[0056] Dimensional accuracy: The mold dimensional accuracy remains at IT7 level, indicating that the mold dimensional accuracy can still be effectively controlled when the process and formula are adjusted.

[0057] Example 3 1. Model parameters This example further adjusts the SLA printing parameters and increases the layer thickness to 0.1mm to further improve the printing efficiency. At the same time, the UV light power is reduced to 80mW / cm 2 , in order to adapt to the changes in energy demand caused by changes in layer thickness and ensure the curing effect of photosensitive resin.

[0058] The model's injection channel diameter is set at 30mm, and the exhaust channel diameter is 12mm, with a ratio of 1 / 2.5. This size design, combined with the characteristics of the filler, can meet the requirements of injection and exhaust.

[0059] 2. Filler formula The amount of epoxy resin used remained unchanged at 1000 g.

[0060] The upper limit of diluent (16-hexanediol diglycidyl ether) is 100g, which accounts for 10% of the epoxy resin mass. A higher diluent dosage can minimize the viscosity of the filler, accommodating finer injection channels and more complex model structures.

[0061] The amount of defoaming agent is increased to 20g, accounting for 2%, to address the problem of increased bubbles caused by the increase in diluent dosage and ensure the surface quality of the mold.

[0062] The aggregate is a composite of 200g titanium dioxide and 600g corundum (400 mesh), accounting for 80% of the total. Titanium dioxide improves the mold's whiteness and hiding power, while corundum provides high hardness and wear resistance. The combination of the two further optimizes the mold's performance.

[0063] The dosage of silane coupling agent (KH-550) is 15g, accounting for 1.5%, which enhances the interfacial bonding strength between composite aggregate and epoxy resin.

[0064] The dosage of amine curing agent is 600g, accounting for 60%, to ensure that the epoxy resin is fully cured and forms a stable structure.

[0065] 3. Process During vacuum degassing, the vacuum degree is set to -0.08MPa and the time is 5 minutes. According to the characteristics of the filling material and the bubble generation situation, the appropriate vacuum degree and degassing time are selected to effectively remove bubbles and improve production efficiency.

[0066] The infusion pressure was adjusted to 0.2 MPa. The lower infusion pressure combined with the high-fluidity filler can avoid damage to the model due to excessive pressure during the infusion process.

[0067] Curing: The curing process is heated at 40℃ for 6 hours. Curing at a lower temperature for a longer time helps control the rate of the curing reaction, making the curing process more uniform and improving the quality of the mold.

[0068] 4. Performance Temperature tolerance: The mold's temperature tolerance is 100°C, which is relatively low, but can still meet the needs in some specific application scenarios.

[0069] Pressure resistance: It can withstand a pressure of 1.5MPa, which can meet the pressure requirements of general foundry processes.

[0070] Tensile strength: The tensile strength of the mold reaches 162 MPa, which is the highest among the three examples, indicating that the composite aggregate and the adjusted process have a significant effect on improving the tensile properties of the mold.

[0071] Dimensional accuracy: The dimensional accuracy is maintained at IT7 level, which means that the high precision requirements of the mold can still be guaranteed when various parameters are adjusted.

[0072] Epoxy resin wax injection mold based on stereolithography technology is shown in the figure Figure 1-3 . The 3D design of epoxy resin mold based on stereolithography technology is shown in Figure 4-6 .

[0073] Comparative Example 1 Formula: In this comparative example, 16-hexanediol diglycidyl ether was omitted, and the remaining ingredients and amounts were the same as those in Example 1.

[0074] The process is the same as that of Example 1.

[0075] Results: Due to the lack of diluent, the filler viscosity increased significantly. During the infusion process, the mold cavity was not completely filled, with a fill coverage of ≤85%. This was because the high-viscosity filler had difficulty flowing within the mold cavity, unable to reach some small corners. Furthermore, the mold surface porosity increased by 30% after curing, due to the increased viscosity making it difficult for bubbles to escape. The tensile strength dropped to 95 MPa, demonstrating that the diluent plays a crucial role in improving filler fluidity, ensuring the uniformity of the mold's internal structure, and enhancing the mold's mechanical properties.

[0076] Comparative Example 2 Formula: The diluent is replaced with an equal amount of phenyl glycidyl ether, and the other ingredients and amounts remain unchanged from those in Example 1.

[0077] The process is the same as that of Example 1.

[0078] Results: The use of phenyl glycidyl ether accelerated aggregate settling and caused stratification in the mixture. This was attributed to the poor compatibility of phenyl glycidyl ether with the other components, which prevented the aggregate from being effectively dispersed in the epoxy resin. After curing, the mold became locally brittle and cracked when pressurized to 0.8 MPa during casting. This suggests that the type of diluent significantly influences filler stability and mold mechanical properties, with 16-hexanediol diglycidyl ether offering unique advantages.

[0079] Comparative Example 3 The recipe is the same as that of Example 1.

[0080] Process: Increase the curing temperature to 70°C and shorten the curing time to 2 hours. Other steps are the same as in Example 1.

[0081] Results: Excessively high curing temperatures caused thermal decomposition of the epoxy resin, resulting in blistering and deformation on the mold surface. Furthermore, dimensional accuracy dropped to IT10, severely impacting mold quality and performance. This demonstrates that strict control of curing process parameters is crucial for ensuring mold quality and dimensional accuracy; exceeding curing conditions specified in this application can have a significant negative impact on mold performance.

[0082] Comparative Example 4 The recipe is the same as that of Example 1.

[0083] Process: Omit the vacuum degassing step and directly proceed to pouring. Other steps are the same as in Example 1.

[0084] Results: Without vacuum degassing, the mold's internal porosity exceeded 15%. During the wax injection process, when the temperature reached 100°C, the pores expanded due to the heat, causing the mold to crack. This clearly demonstrates the indispensable role of vacuum degassing in removing bubbles from the filler, ensuring internal mold quality, and improving mold stability at high temperatures.

[0085] Matters not covered by the present invention are known technologies.

[0086] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. An epoxy resin mold based on stereolithography technology, characterized by: The epoxy resin mold is composed of a composite of a stereolithography molded part and an epoxy resin-based filler; the stereolithography molded part is a photosensitive resin model prepared by stereolithography, and the photosensitive resin model has a preset cavity structure; The epoxy resin-based filler comprises the following components: epoxy resin, epoxy resin curing agent, aggregate, diluent, defoaming agent and silane coupling agent, wherein the diluent is 16-hexanediol diglycidyl ether, and its addition amount is 1-10% of the mass of the epoxy resin.

2. The method for preparing an epoxy resin mold based on stereolithography technology according to claim 1, characterized in that: The following steps are involved: (1) Prepare a photosensitive resin model with a cavity structure by stereolithography technology. The thickness of the molding layer is 0.05mm-0.15mm and the UV light power is 80mW / cm 2 -120mW / cm 2 ; (2) Preparation of epoxy resin-based filler: Add epoxy resin, diluent, and defoamer to the container in sequence at 25-35°C, and stir at 200-500 rpm for 10-30 minutes; then add aggregate, silane coupling agent, and epoxy resin curing agent in batches while continuing to stir, controlling the stirring temperature to not exceed 40°C, to form a uniformly mixed epoxy resin-based filler; (3) After vacuum degassing, the epoxy resin-based filler is poured into the cavity of the photosensitive resin model at a pouring pressure of 0.2 MPa-0.8 MPa; the filler is allowed to stand and cure at 20°C-25°C for 24 hours-72 hours, or at 40°C-60°C for 2 hours to obtain a composite structure epoxy resin mold based on stereolithography technology.

3. The method for preparing an epoxy resin mold based on stereolithography technology according to claim 2, characterized in that: The cavity structure of the photosensitive resin model in step (1) comprises an injection channel and an exhaust channel that are interconnected. The diameter of the injection channel is 2-5 mm, and the diameter of the exhaust channel is 1 / 3-1 / 2 of the diameter of the injection channel.

4. The method for preparing an epoxy resin mold based on stereolithography technology according to claim 2, characterized in that: The defoamer is a silicone defoamer, and its addition amount is 0.1%-2% of the mass of the epoxy resin; the aggregate is selected from one or more of corundum powder, glass fiber, silica powder, and titanium dioxide with a particle size of 200 mesh to 800 mesh, and its addition amount is 20%-80% of the mass of the epoxy resin; the silane coupling agent is KH-550 or KH-602 coupling agent, and its addition amount is 0.1%-2% of the mass of the epoxy resin.

5. The method for preparing an epoxy resin mold based on stereolithography technology according to claim 2, characterized in that: The epoxy resin curing agent is an amine curing agent or an acid anhydride curing agent, and its addition amount is 30%-60% of the mass of the epoxy resin; the vacuum degassing treatment conditions in step (3) are: vacuum degree -0.08MPa~-0.1MPa, and degassing time is 5 minutes to 15 minutes.

6. The application of the epoxy resin mold based on stereolithography technology according to claim 1, characterized in that: The epoxy resin mold based on the stereolithography molding technology can withstand a temperature of 80° C. to 120° C. when used for wax injection molding, and can withstand a pressure of 0.5 MPa to 2 MPa when used for the sand casting process.

Images