Rapid prototyping process for automotive interior part molds

Abstract

The present invention discloses a rapid prototyping process for automotive interior trim molds, which relates to the field of molds and includes a rapidly curing composite resin material, an injection mold, and a composite coating. The rapidly curing composite resin material flows through the injection mold and undergoes high-pressure injection, and the injection mold has channels for preheating in the early stage, rapid temperature increase in the middle stage, and rapid temperature decrease in the later stage. The composite coating is coated on the inner wall of the injection mold to cooperate with high pressure to accelerate the flow rate of the rapidly curing composite resin material. The present invention improves the mold forming speed from three aspects: improving the cooling and curing speed of the resin material in terms of raw materials, equipping the injection mold with preheating, rapid heating, and rapid cooling channels, and coating the mold with a coating that accelerates the movement of the molten material and does not stick, so as to accelerate the mold forming speed, shorten the injection time of a single mold during the injection of automotive interior trim parts, reduce energy consumption, and thus increase the output.

Description

Technical Field

[0001] The present invention relates to the field of molds, and specifically to a rapid prototyping process for automotive interior part molds. Background Art

[0002] Molds are used in industrial production to Injection molding , Blow molding , Extrusion , Die casting or Forging form, Smelting , Stamping and other methods to obtain various molds and tools for the required products. In short, a mold is a tool used to make formed articles, and this tool consists of various parts Constitute . Different molds are composed of different parts. It mainly realizes the processing of the outer shape of the article by changing the physical state of the formed material. Molds are increasingly an indispensable part of people's production and life. For example, in automobile manufacturing, they can be used to produce steering wheels, automotive instrument panels, seat cushions, headrests, spoilers, automotive interior roofs, etc., and general plastic parts are obtained through the injection molding process of molds.

[0003] In the existing forming process of automotive interior part molds, generally, PVC materials or granular resin materials are melted in an injection mold, then transported, and transported and extruded into the mold to form and then removed. Such a forming process takes a long time, especially when the volume of automotive interior parts is large, such as seats and other parts, this production process is more time-consuming. Therefore, a rapid prototyping process for automotive interior part molds is urgently needed. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide a rapid prototyping process for automotive interior part molds to solve the technical problem that in the existing forming process of automotive interior part molds, generally, PVC materials or granular resin materials are melted in an injection mold, then transported, and transported and extruded into the mold to form and then removed, such a forming process takes a long time, especially when the volume of automotive interior parts is large, such as seats and other parts, this production process is more time-consuming.

[0005] To achieve the above object, the present invention provides the following technical solutions: A rapid prototyping process for automotive interior parts molds, including a rapidly curing composite resin material, an injection mold, and a composite coating. The rapidly curing composite resin material flows through the injection mold and undergoes high-pressure injection, and the injection mold has channels for preheating in the early stage, rapid temperature rise in the middle stage, and rapid temperature drop in the later stage. The composite coating is coated on the inner wall of the injection mold to cooperate with high pressure to accelerate the flow rate of the rapidly curing composite resin material. The rapidly curing composite resin material includes the following mass parts: 60 - 70 mass parts of epoxy resin; 5 - 15 mass parts of silicone sealant; 5 - 15 mass parts of low-temperature curing coupling agent; 3 - 8 mass parts of anti-aging agent; 2 - 8 mass parts of flame retardant.

[0006] Preferably, the silicone sealant includes the following raw materials: 20 - 33 mass parts of polydimethylsiloxane, 20 - 30 mass parts of vinyl silicone oil, 15 - 30 mass parts of hydrogen-containing silicone white carbon black, 10 - 15 mass parts of cross-linking agent, 10 - 20 mass parts of filler, 10 - 22 mass parts of auxiliary agent; wherein the cross-linking agent is one or a mixture of polyisocyanate, silicone, and acrylic acid, wherein the filler is one or a mixture of two or three of calcium carbonate, active calcium, carbon fiber, and glass fiber, and wherein the auxiliary agent is a water repellent. The silicone sealant includes the following forming steps:

[0007] S1: First, use a grinder to grind the filler raw materials. After grinding to a certain extent, then mix two or three of the filler raw materials, and then set aside.

[0008] S2: Use a mixer to mix the polydimethylsiloxane, vinyl silicone oil, and hydrogen-containing silicone white carbon black in the raw materials evenly, and then add the cross-linking agent and filler to it under a heating state, and continue to mix and stir.

[0009] S3: After stirring to a certain extent, add the auxiliary agent to the mixture, and then turn off the mixing equipment and mix evenly under a vacuum state.

[0010] S4: After mixing, take out the mixture, let it dissipate heat and cool down at room temperature, and then let it stand.

[0011] Preferably, the low-temperature curing coupling agent is a phenolic modified amine curing agent, wherein the modified amine includes one of aliphatic amine and aromatic amine, the aldehyde material is salicylaldehyde, the phenolic material includes one or a mixture of hydroquinone and cresol, and the proportion of the modified amine, aldehyde material, and phenolic material is 2:1:1.

[0012] Preferably, the anti-aging agent in the rapidly curing composite resin material is phosphite, the flame retardant is a mixture of red phosphorus and magnesium hydroxide, and the proportion of red phosphorus and magnesium hydroxide is 1:1.5. The rapidly curing composite resin material includes the following forming steps:

[0013] S1: Put a certain proportion of epoxy resin and silicone sealant into a heating kettle for mixing and stirring. Heat up the temperature in the heating kettle to 60 - 85 °C, and then put a certain proportion of low-temperature curing coupling agent into it for mixing together.

[0014] S2: After mixing for a period of time, add anti-aging agent and flame retardant to the mixture for mixing. The mixing temperature is maintained at 80 - 90 °C, and the stirring speed is 60 revolutions per minute.

[0015] S3: After stirring for 4 - 5 hours, lower the stirring speed in the heating kettle to keep it at 30 - 35 revolutions per minute, and keep the temperature unchanged.

[0016] S4: Then transport the molten material into an injection molding machine to prepare for pressure injection molding.

[0017] Preferably, the injection mold includes the following structures: a transportation device, a pressurization device, a transportation preheating housing, a preheating nozzle, an upper mold, a lower mold, a moving component, an ejection component, a heating channel, a cooling channel, and a liquid cooling group. The pressurization device is installed on one side of the transportation device and is responsible for pressurizing the transported material to make it move quickly in the transportation device. The transportation preheating housing is installed outside the transportation device and is responsible for preheating the transportation device to prevent the material from condensing inside and also heating the material moving channel to facilitate accelerating the material moving speed. The preheating nozzle is installed at the end of the transportation device and is responsible for ejecting the material into the mold. The upper mold is installed at the receiving end of the preheating nozzle, and the heating channel is arranged outside the upper mold and the preheating nozzle, aiming to preheat the upper mold and make the material rise in temperature for a short time. The lower mold is installed on the moving component to facilitate moving and closing with the upper mold. The ejection component is installed behind the lower mold to facilitate ejecting the mold after molding. The cooling channel is arranged in the upper mold and the lower mold, and multiple coolant inlets facilitate cooling the mold in a short time. The liquid cooling group is installed outside the cooling channel and is responsible for circulating, pumping in, and pumping out the coolant.

[0018] Preferably, the preheating temperature of the injection mold in the early stage is 90 - 110 °C, the rapid temperature rise in the middle stage is 130 - 140 °C, and the rapid temperature drop in the later stage is 0 - 7 °C.

[0019] Preferably, the composite coating includes the following parts by mass: 40 - 60 parts by mass of silicone, 20 - 35 parts by mass of polytetrafluoroethylene, 15 - 30 parts by mass of sodium lignosulfonate solution, and 10 - 15 parts by mass of boron carbide.

[0020] Preferably, the composite coating includes the following forming steps:

[0021] S1: First, disperse boron carbide through a nano ultrasonic machine, and then put a certain proportion of boron carbide into a high-temperature furnace for heating. At the same time, put the sodium lignosulfonate solution into the furnace and stir to mix them.

[0022] S2: Raise the temperature of the high-temperature furnace and continue to put a certain proportion of silicone and polytetrafluoroethylene into it, and mix and stir them.

[0023] S3: After stirring in the high-temperature furnace for 2 - 2.5 hours, take out the mixture, and then place it in a vacuum mixing device to continue mixing for 1 - 2 hours.

[0024] S4: Take out the mixture and coat it in the injection mold by spraying or immersion.

[0025] Preferably, the method includes the following steps:

[0026] Step 1: First, put the fast-curing composite resin material into the transportation device in the injection mold, and use a pressurizing device to pressurize the fast-curing composite resin material so that it moves forward rapidly in the cavity coated with the composite coating. Since the cavity has been preheated to 90 - 110 °C through the transportation preheating housing in advance, the fast-curing composite resin material moves fast in the cavity and will not solidify.

[0027] Step 2: When the fast-curing composite resin material in the cavity is about to reach the preheating nozzle, the heating cavity will transport the heating oil to the preheating nozzle and the upper mold, and raise the temperature of the preheating nozzle and the upper mold to 130 - 140 °C, so that the fast-curing composite resin material in the molten state is heated again in a short time.

[0028] Step 3: At the same time, the lower mold on one side of the upper mold moves to one side of the upper mold through the moving component. The molds are combined to receive the ejected fast-curing composite resin material. At the same time, the hot oil withdraws, and the coolant is transported into the upper mold and the lower mold through the liquid cooling group and the cooling cavity to rapidly cool the temperature of the molds, so that the materials in the molds are rapidly cooled under the condition of a sudden drop in temperature. Then the moving component drives the lower mold to separate from the upper mold.

[0029] Step 4: The demolding component ejects from the rear side of the lower mold to eject the material for blanking. With the cooperation of the composite coating, the formed mold will not stick, and the blanking is fast, so that the subsequent injection work can be carried out.

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

[0031] 1. The present invention improves the molding speed of the mold by improving the cooling and solidification speed of the resin material on the raw material, equipping the injection mold with preheating, rapid heating, and rapid cooling cavities, and coating the mold with a coating that accelerates the movement of the molten material and does not stick, so that the molding speed of the mold is accelerated, the injection time of a single mold is shortened during the injection molding of automotive interior parts, and energy consumption is reduced, thereby increasing production;

[0032] 2. The present invention improves the cooling and curing speed of the resin material by setting it up, and strengthens the curing speed of the epoxy resin as the base material by adding silicone sealant and low-temperature curing coupling agent to the resin material, so that the fast-curing composite resin material can be quickly cured during the later pre-cooling molding, and cooperates with the accelerated liquid cooling speed of the mold to improve the overall molding efficiency;

[0033] 3. The present invention adds preheating structures to the outside of the injection mold, the nozzle and the upper mold so that the molten material entering the mold cavity is not easy to condense, and the appropriate temperature and pressure can increase the moving speed of the material in the cavity, thereby shortening the overall molding time. The hotter cavity added to the nozzle and the upper mold can make the material entering the nozzle and the upper mold rapidly heated in a short time, and the subsequent rapid cooling of the mold will make the later mold have good pressure resistance, and the rapid cooling process can make the mold quickly molded, and the combined use can shorten the mold molding time;

[0034] 4. The present invention applies a composite coating on the outside of the injection molding module. The silicone in the composite coating can not only enhance the non-stickiness of the mold in the later stage, but also make it easier to speed up the movement of materials when coated in the mold transport cavity. The non-stick coating prevents the material from adhering to the cavity and the inner wall of the mold, thereby increasing the movement speed and shortening the time required for the material to move in the cavity, thereby shortening the time required for the mold to form. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0036] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0037] The following describes an embodiment of the present invention based on its overall structure.

[0038] Example 1

[0039] The rapid prototyping process for automotive interior trim molds includes a fast-curing composite resin material, an injection mold, and a composite coating. The fast-curing composite resin material flows through the injection mold and undergoes high-pressure injection. The injection mold has channels for preheating in the early stage, rapid temperature increase in the middle stage, and rapid temperature decrease in the later stage. The composite coating is applied to the inner wall of the injection mold to cooperate with high pressure to accelerate the flow rate of the fast-curing composite resin material. The fast-curing composite resin material includes the following mass parts: 60 mass parts of epoxy resin; 15 mass parts of silicone sealant; 15 mass parts of low-temperature curing coupling agent; 5 mass parts of anti-aging agent; 5 mass parts of flame retardant.

[0040] Among them, the silicone sealant includes the following raw materials: 30 mass parts of polydimethylsiloxane, 20 mass parts of vinyl silicone oil, 20 mass parts of hydrogen-containing silicone white carbon black, 10 mass parts of cross-linking agent, 10 mass parts of filler, 10 mass parts of auxiliary agent; among them, the cross-linking agent is a mixture of polyisocyanate and silicone, among which the filler is a mixture of calcium carbonate and carbon fiber, and among which the auxiliary agent is a water repellent.

[0041] Among them, the low-temperature curing coupling agent is a phenolic modified amine curing agent, among which the modified amine is a fatty amine, the aldehyde material is salicylaldehyde, and the phenolic material includes a mixture of hydroquinone and cresol. The proportion of the modified amine, aldehyde material, and phenolic material is 2:1:1.

[0042] Among them, the anti-aging agent in the fast-curing composite resin material is phosphite ester, and the flame retardant is a mixture of red phosphorus and magnesium hydroxide, and the proportion of red phosphorus and magnesium hydroxide is 1:1.5.

[0043] Among them, the composite coating includes the following mass parts: 50 mass parts of silicone, 20 mass parts of polytetrafluoroethylene, 20 mass parts of sodium lignosulfonate solution, 10 mass parts of boron carbide.

[0044] It includes the following steps:

[0045] Step 1: First, put the fast-curing composite resin material into the transportation equipment in the injection mold, and use a pressurizing device to pressurize the fast-curing composite resin material so that it moves forward rapidly in the channel coated with the composite coating. Since the channel has been heated to 90 - 110 °C through the transportation preheating shell in advance, the fast-curing composite resin material moves fast in the channel and will not solidify.

[0046] Step 2: When the fast-curing composite resin material in the channel is about to reach the preheating nozzle, the heating channel will transport the heating oil to the preheating nozzle and the upper mold, and raise the temperature of the preheating nozzle and the upper mold to 130 - 140 °C, so that the fast-curing composite resin material in the molten state is heated up again in a short time.

[0047] Step 3: At the same time, the lower mold on one side of the upper mold moves to the side of the upper mold through the moving component. The molds are combined to receive the ejected fast-curing composite resin material. At the same time, the hot oil exits, and the coolant is transported into the upper mold and the lower mold through the liquid cooling group and the cooling channels, rapidly cooling the temperature in the molds, so that the materials in the molds are rapidly cooled under the condition of a sudden drop in temperature. Then, the moving component drives the lower mold to separate from the upper mold;

[0048] Step 4: The demolding component ejects from the rear side of the lower mold to eject the materials for blanking. With the cooperation of the composite coating, the formed mold will not stick, and blanking can be carried out quickly, and then the subsequent injection molding work can be carried out.

[0049] In this embodiment, the fast-curing composite resin material uses a relatively large amount of silicone sealant and low-temperature curing coupling agent, and the cooling speed is fast after being cooled. And a relatively large amount of silicone is used in the composite coating, which can not only enhance the flow rate in the injection mold, but also improve the non-sticking degree with the mold to a certain extent.

[0050] Embodiment 2

[0051] The rapid prototyping process for automotive interior parts molds includes a fast-curing composite resin material, an injection mold, and a composite coating. The fast-curing composite resin material circulates in the injection mold and undergoes high-pressure injection molding. And there are channels for preheating in the early stage, rapid heating in the middle stage, and rapid cooling in the later stage in the injection mold. The composite coating is coated on the inner wall of the injection mold to cooperate with high pressure to accelerate the flow rate of the fast-curing composite resin material. The fast-curing composite resin material includes the following mass parts: 70 mass parts of epoxy resin; 10 mass parts of silicone sealant; 10 mass parts of low-temperature curing coupling agent; 5 mass parts of anti-aging agent; 5 mass parts of flame retardant.

[0052] Among them, the silicone sealant includes the following raw materials: 25 mass parts of polydimethylsiloxane, 30 mass parts of vinyl silicone oil, 15 mass parts of hydrogen-containing silicone white carbon black, 10 mass parts of cross-linking agent, 10 mass parts of filler, 10 mass parts of auxiliary agent; among them, the cross-linking agent is a mixture of polyisocyanate and silicone, among which the filler is a mixture of calcium carbonate and carbon fiber, and among which the auxiliary agent is a water repellent.

[0053] Among them, the low-temperature curing coupling agent is a phenolic modified amine curing agent, among which the modified amine is a fatty amine, the aldehyde material is salicylaldehyde, and the phenolic materials include a mixture of hydroquinone and cresol. The proportion of the modified amine, aldehyde material, and phenolic materials is 2:1:1.

[0054] Among them, the anti-aging agent in the fast-curing composite resin material is phosphite, and the flame retardant is a mixture of red phosphorus and magnesium hydroxide, and the proportion of red phosphorus and magnesium hydroxide is 1:1.5.

[0055] Among them, the composite coating includes 40 parts by mass of silicone, 35 parts by mass of polytetrafluoroethylene, 15 parts by mass of sodium lignosulfonate solution, and 10 parts by mass of boron carbide.

[0056] It includes the following steps:

[0057] Step 1: First, put the fast-curing composite resin material into the transportation device in the injection mold, and use the pressurizing device to pressurize the fast-curing composite resin material so that it moves forward rapidly in the cavity coated with the composite coating. Since the cavity has been preheated to 90 - 110 °C through the transportation preheating shell in advance, the fast-curing composite resin material moves fast in the cavity and will not solidify.

[0058] Step 2: When the fast-curing composite resin material in the cavity is about to reach the preheating nozzle, the heating cavity will transport the heating oil to the preheating nozzle and the upper mold, and raise the temperature in the preheating nozzle and the upper mold to 130 - 140 °C, so that the fast-curing composite resin material in the molten state is heated up again in a short time.

[0059] Step 3: At the same time, the lower mold on one side of the upper mold moves to one side of the upper mold through the moving component. The mold is combined to receive the ejected fast-curing composite resin material. At the same time, the hot oil withdraws, and the coolant is transported into the upper mold and the lower mold through the liquid cooling group and the cooling cavity to rapidly cool the temperature in the mold, so that the material in the mold is rapidly cooled under the condition of a sudden drop in temperature, and then the moving component drives the lower mold to separate from the upper mold.

[0060] Step 4: The demolding component ejects from the rear side of the lower mold to eject the material for blanking. With the cooperation of the composite coating, the forming mold will not stick, and the blanking is fast, so that the subsequent injection work can be carried out.

[0061] In this embodiment, the fast-curing composite resin material uses more epoxy resin, making the properties of the later mold more stable, having a certain cold-curing speed, and the silicone and polytetrafluoroethylene in the composite coating have similar parts by mass, focusing on improving the non-sticking degree with the mold, making the mold blanking speed fast and reducing the breakage rate of the ejecting mold.

[0062] The content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0063] The orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention with a simplified description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the protection content of the present invention.

[0064] 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 perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. The rapid prototyping process for automotive interior trim molds, including rapid-curing composite resin materials, injection molds, and composite coatings, is characterized in that: The fast-curing composite resin material flows in an injection mold and undergoes high-pressure injection. The injection mold has channels for preheating in the early stage, rapid temperature rise in the middle stage, and rapid temperature drop in the later stage. The composite coating is coated on the inner wall of the injection mold to cooperate with high pressure to accelerate the flow rate of the fast-curing composite resin material. The fast-curing composite resin material comprises the following parts by mass: 60-70 parts by mass of epoxy resin; 5-15 parts by mass of silicone sealant; 5-15 parts by mass of low-temperature curing coupling agent; 3-8 parts by mass of anti-aging agent; 2-8 parts by mass of flame retardant; The composite coating comprises the following parts by mass: 40-60 parts by mass of silicone, 20-35 parts by mass of polytetrafluoroethylene, 15-30 parts by mass of sodium lignosulfonate solution, 10-15 parts by mass of boron carbide; The rapid prototyping process for automotive interior part molds comprises the following steps: Step 1: First, the fast-curing composite resin material is put into the transportation equipment in the injection mold, and the fast-curing composite resin material is pressurized by a pressurizing device, so that it rapidly moves forward in the channel coated with the composite coating. Since the channel has been heated to 90-110 °C by a transportation preheating shell in advance, the fast-curing composite resin material moves fast in the channel and will not solidify; Step 2: When the fast-curing composite resin material in the channel is about to reach the preheating nozzle, the heating channel transports heating oil to the preheating nozzle and the upper mold, and raises the temperature of the preheating nozzle and the upper mold to 130-140 °C, so that the fast-curing composite resin material in a molten state is heated up again in a short time; Step 3: At the same time, the lower mold on one side of the upper mold moves to one side of the upper mold through a moving component, the mold is combined to receive the ejected fast-curing composite resin material, and at the same time the hot oil withdraws, and the coolant is transported into the upper mold and the lower mold through a liquid cooling group and a cooling channel to rapidly cool the temperature of the mold, so that the material in the mold is rapidly cooled under the condition of a sudden temperature drop, and then the moving component drives the lower mold to separate from the upper mold; Step 4: The demolding component ejects from the rear side of the lower mold to eject the material for blanking. With the cooperation of the composite coating, the molding mold will not adhere, and blanking is rapid, and subsequent injection work can be carried out.

2. The rapid prototyping process of the automotive interior part mold according to claim 1, characterized in that: The silicone sealant comprises the following raw materials: 20-33 parts by mass of polydimethylsiloxane, 20-30 parts by mass of vinyl silicone oil, 15-30 parts by mass of hydrogen-containing silicone white carbon black, 10-15 parts by mass of cross-linking agent, 10-20 parts by mass of filler, 10-22 parts by mass of auxiliary agent; wherein the cross-linking agent is one or more mixtures of polyisocyanate, silicone, and acrylic acid, wherein the filler is one or a mixture of two or three of calcium carbonate, active calcium, carbon fiber, and glass fiber, and wherein the auxiliary agent is a water repellent. The silicone sealant comprises the following molding steps: S1: First, the filler raw materials are ground by a grinding machine. After grinding to a certain extent, two or three of the filler raw materials are mixed, and then reserved; S2: Use a mixer to mix polydimethylsiloxane, vinyl silicone oil, hydrogen-containing silicone oil, and silica in the raw materials evenly, and then add a cross-linking agent and a filler to it under heating, and continue to mix and stir. S3: After stirring to a certain extent, add an auxiliary agent to the mixture, then turn off the mixing equipment, and mix evenly under a vacuum state. S4: After mixing, take out the mixture, let it dissipate heat and cool down at room temperature, and then let it stand.

3. The rapid prototyping process of the automotive interior part mold according to claim 1, characterized in that: The low-temperature curing coupling agent is a phenolic modified amine curing agent, where the modified amine includes one of aliphatic amine and aromatic amine, the aldehyde material is salicylaldehyde, the phenolic material includes one or both of hydroquinone and cresol, and the proportion of the modified amine, aldehyde material and phenolic material is 2:1:

1.

4. The rapid prototyping process of the automotive interior part mold according to claim 1, characterized in that: The anti-aging agent in the fast-curing composite resin material is phosphite, the flame retardant is a mixture of red phosphorus and magnesium hydroxide, and the proportion of red phosphorus and magnesium hydroxide is 1:1.

5. The fast-curing composite resin material includes the following molding steps: S1: Put a certain proportion of epoxy resin and silicone sealant into a heating kettle and mix and stir, raise the temperature in the heating kettle to 60 - 85 °C, and then put a certain proportion of low-temperature curing coupling agent into it and mix together. S2: After mixing for a period of time, add the anti-aging agent and the flame retardant to the mixture for mixing, keep the mixing temperature at 80 - 90 °C, and the stirring speed is 60 revolutions per minute. S3: After stirring for 4 - 5 hours, lower the stirring speed in the heating kettle to keep it at 30 - 35 revolutions per minute, and keep the temperature unchanged. S4: Then transport the molten material into an injection molding machine to prepare for pressure injection molding.

5. The rapid prototyping process for automotive interior part molds according to claim 1, characterized in that: The injection mold includes the following structures: a transportation device, a pressurization device, a transportation preheating housing, a preheating nozzle, an upper mold, a lower mold, a moving component, a mold ejection component, a heating channel, a cooling channel, and a liquid cooling group. The pressurization device is installed on one side of the transportation device and is responsible for pressurizing the transported material to make it move quickly in the transportation device. The transportation preheating housing is installed on the outside of the transportation device and is responsible for preheating the transportation device to prevent the material from condensing inside and also heating the material moving channel to facilitate accelerating the material movement speed. The preheating nozzle is installed at the end of the transportation device and is responsible for spraying the material into the mold. The upper mold is installed at the receiving end of the preheating nozzle, and the heating channel is arranged outside the upper mold and the preheating nozzle, aiming to preheat the upper mold and make the material heat up for a short time. The lower mold is installed on the moving component to facilitate moving and closing with the upper mold. The mold ejection component is installed behind the lower mold to facilitate ejecting the mold after molding. The cooling channel is arranged in the upper mold and the lower mold, and multiple coolant inlets facilitate cooling the mold in a short time. The liquid cooling group is installed outside the cooling channel and is responsible for circulating, pumping in, and pumping out the coolant.

6. The rapid prototyping process of the automotive interior part mold according to claim 1, characterized in that: The preheating temperature of the injection mold in the early stage is 90 - 110 °C, the rapid heating temperature in the middle stage is 130 - 140 °C, and the rapid cooling temperature in the later stage is 0 - 7 °C.

7. The rapid prototyping process for automotive interior trim part molds according to claim 1, characterized in that: The composite coating includes the following molding steps: S1: First, disperse boron carbide in a nano ultrasonic machine, then put a certain proportion of boron carbide into a high-temperature furnace for heating, and put the sodium lignosulfonate solution together and stir and mix them; S2: Raise the temperature of the high-temperature furnace, continue to put a certain proportion of silicone and polytetrafluoroethylene into it, and mix and stir them; S3: After stirring in the high-temperature furnace for 2 - 2.5 hours, take out the mixture, and then place it in a vacuum mixing device and continue to mix for 1 - 2 hours; S4: Take out the mixture and coat it on the injection mold by spraying or immersion.

Images