Vacuum preparation device for artificial rock sample

Abstract

Belonging to the field of composite material preparation, the invention provides an artificial rock sample vacuum preparation device, which comprises a sample tank, a control valve, a vacuum integration tank, a sample preparation mold, a stirring controller, a temperature sensor, a filter device, a vacuum pump and a temperature controller. A sealing connector is arranged on a top cover of the sample tank, the inside of the sample tank is communicated with one side of the vacuum integration tank through a first pipeline, a control valve is arranged on the first pipeline, the other side of the vacuum integration tank is communicated with the vacuum pump through a second pipeline, a filtering device is arranged in the second pipeline, and the sample preparation mold is arranged in the vacuum integration tank. The stirring controller is connected with the top of the vacuum integrated tank, the temperature sensor is arranged in the vacuum integrated tank, and the temperature controller is connected with the temperature sensor. The problems that in a traditional epoxy resin and solid particle mixing experiment, operation is tedious, bubbles are difficult to remove, and temperature control is inconvenient are solved; the structure is compact and the operation is convenient.

Description

Technical Field

[0001] The present invention relates to the field of composite material preparation, and in particular to a vacuum preparation device for artificial rock samples. Background Art

[0002] Artificial rock samples are often used in nanoindentation research of composite materials. For example, samples are prepared by mixing a polymer matrix such as epoxy resin with fillers such as sand. Traditionally, the solid particles are manually poured into liquid epoxy resin and stirred under normal pressure, and the mixture is then exposed to air to cure. This method not only makes it difficult to ensure sample consistency, but also easily introduces air during the manual addition and stirring process. Furthermore, due to the high viscosity of epoxy resin, bubbles are difficult to expel after mixing with particles such as sand, resulting in a large number of bubbles remaining in the final material, seriously affecting the sample quality.

[0003] Currently, specialized vacuum mixing equipment is commercially available, such as vacuum degassing machines or planetary vacuum mixers. These devices evacuate the container during mixing to reduce bubble formation. However, most existing equipment still requires manual pre-addition of solid fillers to the resin before placing the mixing container into the equipment. Alternatively, these devices are complex and bulky, with independent vacuum chambers and mixing systems, resulting in high costs and unsuitable for small-batch testing of tiny rock samples in typical laboratories. Furthermore, while some devices have heating capabilities, they typically utilize external heating jackets or simple insulation, resulting in limited temperature control accuracy and efficiency.

[0004] Existing technical solutions for preparing epoxy resin-sand two-phase artificial rock samples for nanoindentation testing have the following shortcomings: First, the feeding process relies on manual labor and is separated from the vacuum process, making automatic feeding impossible in a vacuum environment. Second, the degassing process is often performed separately after stirring, which is inefficient and cannot ensure mixing uniformity while completely removing bubbles. Third, temperature control requires the use of an external constant temperature box or heating plate, making the process discontinuous and difficult to adjust in real time. Therefore, there is an urgent need for an integrated micro-artificial rock sample preparation device that can complete the entire process of feeding, stirring, degassing, temperature control, and curing under vacuum conditions, accelerating the sample preparation process and improving product quality. Summary of the Invention

[0005] The purpose of the present invention is to provide a vacuum preparation device for artificial rock samples, which solves the problems existing in traditional epoxy resin and solid particle mixing experiments, such as cumbersome operation, difficult bubble removal, and inconvenient temperature control. At the same time, it has a compact structure and is easy to operate. Researchers can efficiently complete the preparation experiment of epoxy resin-based composite materials on a single device and obtain a bubble-free, homogeneous resin-particle mixture.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An artificial rock sample vacuum preparation device is characterized by comprising a sample tank, a control valve, a vacuum integrated tank, a sample preparation mold, a stirring controller, a temperature sensor, a filtering device, a vacuum pump and a temperature controller.

[0008] A sealing interface is provided on the top cover of the sample tank, the interior of the sample tank is connected to one side of the vacuum integrated tank through a first pipeline, a control valve is provided on the first pipeline, the other side of the vacuum integrated tank is connected to the vacuum pump through a second pipeline, a filtering device is provided inside the second pipeline, the sample preparation mold is arranged inside the vacuum integrated tank, the stirring controller is connected to the top of the vacuum integrated tank, the temperature sensor is arranged inside the vacuum integrated tank, and the temperature controller is connected to the temperature sensor.

[0009] Furthermore, the vacuum integrated tank includes a sealed connection interface, a motor, a stirring paddle and a heating layer.

[0010] A sealed connection interface is provided on the top cover of the vacuum integrated tank, the motor is arranged above the top cover of the vacuum integrated tank, the bottom paddle of the stirring paddle extends into the interior of the sample preparation mold, the top of the stirring paddle is connected to the motor through the sealed connection interface, the motor is connected to the stirring controller, a sealed bearing is provided at the connection between the stirring paddle and the sealed connection interface, and the heating layer is arranged at the bottom of the vacuum integrated tank.

[0011] Furthermore, the heating layer includes a metal heat-conducting layer and a heating wire. The bottom of the metal heat-conducting layer is in close contact with the bottom of the vacuum integrated tank, and the top of the metal heat-conducting layer is in close contact with the bottom of the sample preparation mold. The heating wire surrounds or is embedded in the metal heat-conducting layer. The heating wire is powered and temperature-controlled by a temperature controller.

[0012] Furthermore, the diameter of the sample making mold is smaller than the diameter of the tank mouth of the vacuum integrated tank, the size of the sample making mold matches the required size of the artificial rock sample, and the sample making mold is made of flexible silicone material.

[0013] Furthermore, the temperature sensor is arranged on the inner tank wall of the vacuum integrated tank, and the temperature sensor is a PT100 platinum resistance temperature sensor.

[0014] Furthermore, the outer shell of the filter device is made of high-strength transparent polycarbonate, and the filter element of the filter device is composed of a coarse filter mesh and a hydrophilic / hydrophobic composite membrane layer made of polytetrafluoroethylene.

[0015] Furthermore, the vacuum pump is equipped with a vacuum gauge, and the vacuum pump is an oil vane vacuum pump or a dry vacuum pump.

[0016] A method for using an artificial rock sample vacuum preparation device, characterized by comprising the following steps:

[0017] S1. Vacuum pretreatment: Pour a predetermined amount of sand particles into the sample preparation mold, open the top cover of the vacuum integrated tank, place the sample preparation mold into the tank of the vacuum integrated tank, close the top cover of the vacuum integrated tank and ensure that it is well sealed, and close the control valve connected to the sample tank. At this time, the epoxy resin liquid is still placed in the sample tank at normal pressure. Start the vacuum pump, evacuate the vacuum integrated tank to the set vacuum degree and maintain it for a period of time. No stirring is performed at this stage. Let the sand particles fully discharge the gas inside the pores and the air mixed in during the early pouring in a static vacuum environment.

[0018] S2. Vacuum feeding: After pre-degassing is completed and the vacuum integrated tank is kept in a near-vacuum state, open the control valve connected to the sample tank. Since the vacuum integrated tank is at low pressure and the sample tank is still at atmospheric pressure, the resulting pressure difference will quickly push and suck the epoxy resin in the sample tank into the sample preparation mold in the vacuum integrated tank, and then contact and mix with the sand particles. The entire feeding process is carried out in the first pipeline without manual intervention. The injection of epoxy resin can be completed within seconds. After the feeding is completed, the control valve can be closed again to prevent external air from continuing to enter.

[0019] S3. Vacuum stirring and continuous degassing: After the liquid epoxy resin is injected into the sample preparation mold, the motor connected to the stirring paddle is immediately started to stir the resin-particle mixture. The vacuum pump continues to work during the stirring process to maintain a high vacuum in the vacuum integrated tank and continuously extract the bubbles generated by stirring out of the vacuum integrated tank to achieve degassing while stirring. The speed and stirring time of the stirring paddle are controlled by the stirring controller according to the preset program. It can be pre-mixed at a low speed and then fully stirred at a high speed to ensure that the particles are evenly dispersed in the resin matrix. Since it is always in a vacuum state, the newly generated bubbles during stirring will escape in time and be taken away by the vacuum pump, thereby avoiding bubbles being trapped in the mixture.

[0020] S4. Heating, temperature control and curing: During or after stirring, start the heating layer at the bottom of the vacuum integrated tank. The temperature controller adjusts the heating power according to the temperature sensor reading to heat the mixture to the required temperature and maintain it for a certain period of time. The vacuum environment is still maintained during the heating process to prevent residual bubbles from expanding and being unable to escape due to temperature rise. The temperature control adopts closed-loop adjustment to ensure that the heating rate and equilibrium temperature meet the experimental requirements and avoid damage to the resin performance due to overheating. After reaching the predetermined curing time or temperature, stop heating and turn off the vacuum pump to restore the vacuum integrated tank to normal pressure. Finally, open the top cover of the vacuum integrated tank and take out the resin particle mixture that has been mixed evenly and degassed thoroughly in the sample preparation mold to complete the experimental preparation process.

[0021] Advantages of the present invention:

[0022] 1. Overcome the damage to the vacuum environment caused by manual feeding and realize the method of automatically mixing particles with resin by using the pressure difference between vacuum and atmospheric pressure, so as to ensure that the feeding process is fast and efficient and avoid the introduction of new air.

[0023] 2. Integrated stirring and continuous vacuuming functions instantly remove bubbles during mixing, improving resin-particle mixing uniformity while minimizing residual bubbles. The resulting resin-particle slurry is dense and uniform, which is particularly important for the preparation of artificial rock samples requiring high performance and reliability.

[0024] 3. Integrating heating and temperature sensor components in the mixing container can heat and control the temperature of the mixture in real time, reduce the viscosity of the resin to facilitate stirring and degassing, and accelerate the thermal curing process of the epoxy system (when necessary), thereby shortening the experimental cycle.

[0025] 4. By organically combining functional modules such as vacuuming, feeding, stirring, heating and curing into one device, the human intervention steps and errors are reduced, the experimental repeatability and efficiency are improved, and it is suitable for small-batch tests of tiny artificial rock samples in the laboratory. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the present invention;

[0027] Figure 2 This is a schematic structural diagram of the vacuum integrated tank in the present invention;

[0028] Figure 3 Schematic diagram of the structure of the heating layer in the present invention;

[0029] In the figure: 1. Sample tank, 2. Control valve, 3. Vacuum integrated tank, 3-1. Sealing connection interface, 3-2. Motor, 3-3. Stirring paddle, 3-4. Heating layer, 3-4-1. Metal heat conductive layer, 3-4-2. Heating wire, 4. Sample preparation mold, 5. Stirring controller, 6. Temperature sensor, 7. Filter device, 8. Vacuum pump, 9. Temperature controller. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0031] like Figure 1 As shown, an artificial rock sample vacuum preparation device includes a sample tank 1, a control valve 2, a vacuum integrated tank 3, a sample preparation mold 4, a stirring controller 5, a temperature sensor 6, a filtering device 7, a vacuum pump 8 and a temperature controller 9.

[0032] A sealing interface is provided on the top cover of the sample tank 1. The interior of the sample tank 1 is connected to one side of the vacuum integrated tank 3 through a first pipeline. A control valve 2 is provided on the first pipeline. The other side of the vacuum integrated tank 3 is connected to the vacuum pump 8 through a second pipeline. A filtering device 7 is provided inside the second pipeline. The sample preparation mold 4 is arranged inside the vacuum integrated tank 3. The stirring controller 5 is connected to the top of the vacuum integrated tank 3. The temperature sensor 6 is arranged inside the vacuum integrated tank 3, and the temperature controller 9 is connected to the temperature sensor 6.

[0033] Sample tank 1 is used to temporarily store the epoxy resin needed to prepare the artificial rock sample. Experimenters add more epoxy resin based on specific sample preparation requirements. Sample tank 1 is at atmospheric pressure during initial addition. When control valve 2 is opened, atmospheric pressure pushes the epoxy resin into sample preparation mold 4 within vacuum integrated tank 3. The volume and sealing design of sample tank 1 can be selected based on experimental requirements to ensure sufficient space and prevent moisture and contamination.

[0034] Control valve 2 is used to control the opening and closing of the first pipeline. During the initial vacuuming phase, control valve 2 is closed to isolate vacuum integrated tank 3 from sample tank 1. After degassing is complete within vacuum integrated tank 3, control valve 2 is opened to draw the epoxy resin into vacuum integrated tank 3 using the pressure differential.

[0035] The first pipeline is used to transport the epoxy resin in the sample tank 1 to the sample preparation mold 4, and the second pipeline is used to extract the gas in the vacuum integrated tank 3.

[0036] As a preferred embodiment of the present invention, Figure 2 As shown, the vacuum integrated tank 3 includes a sealed connection interface 3-1, a motor 3-2, a stirring paddle 3-3 and a heating layer 3-4.

[0037] A sealed connection interface 3-1 is provided on the top cover of the vacuum integrated tank 3, the motor 3-2 is provided above the top cover of the vacuum integrated tank 3, the bottom paddle of the stirring paddle 3-3 extends into the interior of the sample preparation mold 4, the top of the stirring paddle 3-3 passes through the sealed connection interface 3-1 and is connected to the motor 3-2, the motor 3-2 is connected to the stirring controller 5, and a sealed bearing is provided at the connection between the stirring paddle 3-3 and the sealed connection interface 3-1, and the heating layer 3-4 is provided at the bottom of the vacuum integrated tank 3.

[0038] The vacuum integrated tank 3 can withstand a vacuum environment and accommodate solid particulate materials (such as sand particles) and absorbed liquid materials (such as epoxy resin). The vacuum integrated tank has good sealing performance and is made of corrosion-resistant and easy-to-clean materials such as thick-walled glass and organic glass. The top cover of the vacuum integrated tank 3 is designed to be removable to facilitate cleaning and removal of the mixed sample preparation mold 4.

[0039] A stirring paddle 3-3 is used to mechanically stir and mix the epoxy resin and sand mixture. It is driven by a motor 3-2. The stirring paddle 3-3 can be a propeller or blade type. Its size and shape are optimized based on the size of the sample preparation mold 4 and the viscosity of the epoxy resin and sand mixture to ensure uniform mixing. The stirring blades are strong enough to handle high-viscosity resins and cover the bottom of the cup as much as possible to avoid dead corners. The stirring controller 5 can adjust the speed of the motor 3-2 to achieve different levels of stirring intensity.

[0040] As a preferred embodiment of the present invention, Figure 3 As shown, the heating layer 3-4 is used to heat the resin-particle mixture in the sample making mold 4. The heating layer 3-4 includes a metal heat-conducting layer 3-4-1 and a heating wire 3-4-2. The bottom of the metal heat-conducting layer 3-4-1 is in close contact with the bottom of the vacuum integrated tank 3 to ensure uniform heat transfer. The top of the metal heat-conducting layer 3-4-1 is in close contact with the bottom of the sample making mold 4 to facilitate heat conduction. The heating wire 3-4-2 surrounds or is embedded in the metal heat-conducting layer 3-4-1. The heating wire 3-4-2 is powered and temperature-controlled by a temperature controller 9. The heating layer 3-4 is compactly designed and does not directly contact the resin-particle mixture, ensuring that the heated surface is uniform and the temperature rise and fall are easy to control.

[0041] As a preferred embodiment of the present invention, the diameter of the sample preparation mold 4 is smaller than the diameter of the opening of the vacuum integrated tank 3, facilitating placement and removal. The size of the sample preparation mold 4 matches the required size of the artificial rock sample. The sample preparation mold 4 is made of a flexible silicone material with good demolding properties and temperature resistance.

[0042] The sample preparation mold 4 is used to hold sand particles, which are then injected and cured to form an artificial rock sample. This improves sample forming efficiency and prevents material contamination of the vacuum integrated tank 3. After the sand particles and epoxy resin are mixed within the sample preparation mold 4, all stirring, heating, degassing, and curing processes are carried out within it, effectively improving sample preparation efficiency and sample integrity. The sample preparation mold 4 is reusable and easy to clean and replace.

[0043] In a preferred embodiment of the present invention, temperature sensor 6 is disposed on the inner wall of vacuum integrated tank 3 to accurately reflect the temperature of the resin-particle mixture while avoiding affecting the movement of stirring paddle 3-3. Temperature sensor 6 is a PT100 platinum resistance temperature sensor, which is chemically resistant and suitable for epoxy resin systems.

[0044] The temperature sensor 6 is used to monitor the temperature of the mixture in real time and feeds back the temperature signal to the temperature controller 9 to achieve closed-loop temperature control.

[0045] In a preferred embodiment of the present invention, the housing of the filter device 7 is made of high-strength transparent polycarbonate, and the filter element of the filter device 7 is composed of a coarse filter mesh and a hydrophilic / hydrophobic composite membrane layer composed of polytetrafluoroethylene. The filter device 7 is used to prevent the resin-particle mixture from being drawn into the vacuum pump 8 during vacuuming and causing contamination, while also facilitating the recovery of deposited liquid.

[0046] In a preferred embodiment of the present invention, the vacuum pump 8 is equipped with a vacuum gauge for monitoring real-time pressure. The vacuum pump 8 is an oil-operated rotary vacuum pump or a dry vacuum pump. The vacuum pump 8 is used to evacuate the interior of the vacuum manifold 3 to create a low-pressure environment. The vacuum pump 8 should be able to reduce the air pressure within the vacuum manifold 3 to the target vacuum level in a relatively short period of time.

[0047] The device presented in this invention is the first laboratory mixing device to utilize vacuum pressure differentials for epoxy resin feeding. Through the unique connection between the sample tank 1 and the vacuum manifold 3, and the control valve 2, the epoxy resin liquid is automatically drawn into the vacuum manifold 3 under vacuum conditions. This eliminates the need to manually open the lid for feeding, thus preventing damage to the vacuum environment and operator error. This simple and reliable automatic feeding method is suitable for feeding high-viscosity liquid systems such as epoxy resin, and represents an innovative design for small-scale vacuum mixing equipment.

[0048] The device of the present invention integrates a heating layer 3-4 consisting of an efficient metal heat-conducting layer 3-4-1 and heating wires 3-4-2 at the bottom of the vacuum integrated tank 3, and is equipped with a precise temperature sensor 6 and temperature controller 9 to achieve real-time temperature control of the mixing process. Compared with traditional external heating or simple insulation, the heating layer 3-4 of the present invention is integrated with the vacuum integrated tank 3, which transfers heat directly and rapidly, and has high temperature control accuracy. The mixture can be heated as needed to reduce viscosity or accelerate curing. This bottom heating and temperature sensing design is unique among laboratory mixing devices.

[0049] The present invention integrates a stirring paddle 3-3 and a vacuum pump 8 within a single container system, forming a synchronous vacuum stirring and degassing device. This device continuously evacuates and exhausts the material while stirring the mixture, achieving dynamic degassing. Unlike existing solutions that require separate stirring and vacuum degassing steps, the present invention achieves integrated, continuous operation, significantly improving experimental efficiency and mixing quality. It is particularly suitable for preparing artificial rock samples in the laboratory.

[0050] A method for using an artificial rock sample vacuum preparation device comprises the following steps:

[0051] S1. Vacuum pretreatment: Pour a predetermined amount of sand particles into the sample preparation mold 4, open the top cover of the vacuum integrated tank 3, place the sample preparation mold 4 into the tank of the vacuum integrated tank 3, close the top cover of the vacuum integrated tank 3 and ensure that it is well sealed, and close the control valve 2 connected to the sample tank 1. At this time, the epoxy resin liquid is still placed in the sample tank 1 at normal pressure. Start the vacuum pump 8, evacuate the vacuum integrated tank 3 to the set vacuum degree and maintain it for a period of time. No stirring is performed at this stage, so that the sand particles can fully discharge the gas inside the pores and the air mixed in during the early pouring under a static vacuum environment.

[0052] S2. Vacuum feeding: After pre-degassing is completed and the vacuum integrated tank 3 is kept in a state close to vacuum, open the control valve 2 connected to the sample tank 1. Since the vacuum integrated tank 3 is at low pressure and the sample tank 1 is still at atmospheric pressure, the resulting pressure difference will quickly push and suck the epoxy resin in the sample tank 1 into the sample preparation mold 4 in the vacuum integrated tank 3, and then contact and mix with the sand particles. The entire feeding process is carried out in the first pipeline without manual intervention. The injection of epoxy resin can be completed within seconds. After the feeding is completed, the control valve 2 can be closed again to prevent the outside air from continuing to enter. This step utilizes the vacuum-atmospheric pressure linkage principle to automate the feeding process and avoid destroying the vacuum environment or introducing additional bubbles.

[0053] S3. Vacuum stirring and continuous degassing: After the liquid epoxy resin is injected into the sample preparation mold 4, the motor 3-2 connected to the stirring paddle 3-3 is immediately started to stir the resin-particle mixture. The vacuum pump 8 continues to work during the stirring process to maintain a high vacuum in the vacuum integrated tank 3 and continuously extract the bubbles generated by stirring out of the vacuum integrated tank 3, so as to achieve degassing while stirring. The speed and stirring time of the stirring paddle 3-3 are controlled by the stirring controller 5 according to the preset program. It can be pre-mixed at a low speed and then fully stirred at a high speed to ensure that the particles are evenly dispersed in the resin matrix. Since it is always in a vacuum state, the newly generated bubbles during stirring will escape in time and be taken away by the vacuum pump 8, thereby avoiding bubbles being trapped in the mixture. This simultaneous stirring and vacuum degassing method significantly improves the degassing efficiency. It is more efficient than the traditional method of stirring first and then standing for vacuum degassing, and also ensures that the mixing process continues in an environment without bubble interference. The stirring process can last for several minutes as needed until the mixture reaches the target uniformity.

[0054] S4. Heating, temperature control, and curing: During or after stirring, the heating layer 3-4 at the bottom of the vacuum integrated tank 3 is activated. The temperature controller 9 adjusts the heating power according to the reading of the temperature sensor 6, heating the mixture to the desired temperature and maintaining it for a certain period of time. Heating has a dual effect: first, moderate heating can reduce the viscosity of the epoxy resin, further facilitating the infiltration of particles and the escape of bubbles; second, it can trigger or accelerate the curing reaction of the resin, allowing the mixture to be partially cured and formed directly in the mold inside the tank. During the heating process, the vacuum environment is maintained to prevent residual bubbles from expanding and escaping due to the increase in temperature. The temperature control adopts closed-loop regulation to ensure that the heating rate and equilibrium temperature meet the experimental requirements and avoid damage to the resin performance caused by overheating. After reaching the predetermined curing time or temperature, the heating is stopped and the vacuum pump 8 is turned off to restore the pressure inside the vacuum integrated tank 3. Finally, the top cover of the vacuum integrated tank 3 is opened to remove the resin particle mixture that has been mixed evenly and thoroughly degassed in the sample preparation mold 4, completing the experimental preparation process.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art may adjust the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Therefore, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is intended to include such modifications and variations.

Claims

1. An artificial rock sample vacuum preparation device, characterized by: It comprises a sample tank (1), a control valve (2), a vacuum integrated tank (3), a sample preparation mold (4), a stirring controller (5), a temperature sensor (6), a filtering device (7), a vacuum pump (8) and a temperature controller (9); A sealing interface is provided on the top cover of the sample tank (1); the interior of the sample tank (1) is connected to one side of the vacuum integrated tank (3) through a first pipeline; a control valve (2) is provided on the first pipeline; the other side of the vacuum integrated tank (3) is connected to a vacuum pump (8) through a second pipeline; a filtering device (7) is provided inside the second pipeline; the sample preparation mold (4) is provided inside the vacuum integrated tank (3); the stirring controller (5) is connected to the top of the vacuum integrated tank (3); the temperature sensor (6) is provided inside the vacuum integrated tank (3); and the temperature controller (9) is connected to the temperature sensor (6).

2. The artificial rock sample vacuum preparation device according to claim 1, characterized in that: The vacuum integrated tank (3) comprises a sealed connection interface (3-1), a motor (3-2), a stirring paddle (3-3) and a heating layer (3-4); A sealed connection interface (3-1) is provided on the top cover of the vacuum integrated tank (3); the motor (3-2) is provided above the top cover of the vacuum integrated tank (3); the bottom blade of the stirring paddle (3-3) extends into the interior of the sample preparation mold (4); the top of the stirring paddle (3-3) passes through the sealed connection interface (3-1) and is connected to the motor (3-2); the motor (3-2) is connected to the stirring controller (5); a sealed bearing is provided at the connection between the stirring paddle (3-3) and the sealed connection interface (3-1); and the heating layer (3-4) is provided at the bottom of the vacuum integrated tank (3).

3. The artificial rock sample vacuum preparation device according to claim 2, characterized in that: The heating layer (3-4) comprises a metal heat-conducting layer (3-4-1) and a heating wire (3-4-2). The bottom of the metal heat-conducting layer (3-4-1) is in close contact with the bottom of the vacuum integrated tank (3), and the top of the metal heat-conducting layer (3-4-1) is in close contact with the bottom of the sample preparation mold (4). The heating wire (3-4-2) surrounds or is embedded in the metal heat-conducting layer (3-4-1). The heating wire (3-4-2) is powered and temperature-controlled by a temperature controller (9).

4. The artificial rock sample vacuum preparation device according to claim 3, characterized in that: The diameter of the sample preparation mold (4) is smaller than the diameter of the tank mouth of the vacuum integrated tank (3), the size of the sample preparation mold (4) matches the required size of the artificial rock sample, and the sample preparation mold (4) is made of a flexible silicone material.

5. The artificial rock sample vacuum preparation device according to claim 4, characterized in that: The temperature sensor (6) is arranged on the inner tank wall of the vacuum integrated tank (3), and the temperature sensor (6) is a PT100 platinum resistance temperature sensor.

6. The artificial rock sample vacuum preparation device according to claim 5, characterized in that: The outer shell of the filter device (7) is composed of high-strength transparent polycarbonate, and the filter element of the filter device (7) is composed of a coarse filter screen and a hydrophilic / hydrophobic composite membrane layer composed of polytetrafluoroethylene.

7. The artificial rock sample vacuum preparation device according to claim 6, characterized in that: The vacuum pump (8) is equipped with a vacuum gauge, and the vacuum pump (8) is an oil rotary vacuum pump or a dry vacuum pump.

8. A method for using the artificial rock sample vacuum preparation device according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Vacuum pretreatment: Pour a predetermined amount of sand particles into the sample preparation mold (4), open the top cover of the vacuum integrated tank (3), place the sample preparation mold (4) into the tank of the vacuum integrated tank (3), close the top cover of the vacuum integrated tank (3) and ensure that it is well sealed, close the control valve (2) connected to the sample tank (1), at this time the epoxy resin liquid is still placed in the sample tank (1) at normal pressure, start the vacuum pump (8), evacuate the vacuum integrated tank (3) to the set vacuum degree and maintain it for a period of time, do not stir at this stage, and let the sand particles fully discharge the gas inside the pores and the air mixed in when pouring in the early stage under a static vacuum environment; S2. Vacuum feeding: After the pre-degassing is completed and the vacuum integrated tank (3) is kept in a state close to vacuum, the control valve (2) connected to the sample tank (1) is opened. Since the vacuum integrated tank (3) is at low pressure while the sample tank (1) is still at atmospheric pressure, the pressure difference generated will quickly push and suck the epoxy resin in the sample tank (1) into the sample preparation mold (4) in the vacuum integrated tank (3), and then contact and mix with the sand particles. The entire feeding process is carried out in the first pipeline without manual intervention. The injection of epoxy resin can be completed within a few seconds. After the feeding is completed, the control valve (2) can be closed again to prevent the outside air from continuing to enter; S3. Vacuum stirring and continuous degassing: After the liquid epoxy resin is injected into the sample preparation mold (4), the motor (3-2) connected to the stirring paddle (3-3) is immediately started to stir the resin-particle mixture. The vacuum pump (8) continues to work during the stirring process to maintain a high vacuum in the vacuum integrated tank (3) and continuously extract the bubbles generated by stirring out of the vacuum integrated tank (3) to achieve degassing while stirring. The speed and stirring time of the stirring paddle (3-3) are controlled by the stirring controller (5) according to a preset program. The mixture can be pre-mixed at a low speed and then fully stirred at a high speed to ensure that the particles are evenly dispersed in the resin matrix. Since the mixture is always in a vacuum state, the newly generated bubbles will escape in time during stirring and be taken away by the vacuum pump (8), thereby preventing the bubbles from being trapped in the mixture. S4. Heating, temperature control and curing: During or after the stirring process, the heating layer (3-4) at the bottom of the vacuum integrated tank (3) is started, and the temperature controller (9) adjusts the heating power according to the reading of the temperature sensor (6), and the mixture is heated to the required temperature and maintained for a certain time. During the heating process, the vacuum environment is still maintained to prevent the residual bubbles from expanding and being unable to escape due to the temperature increase. The temperature control adopts closed-loop regulation to ensure that the heating rate and the equilibrium temperature meet the experimental requirements and avoid damage to the resin performance due to overheating. After the predetermined curing time or temperature is reached, the heating is stopped and the vacuum pump (8) is turned off to restore the vacuum integrated tank (3) to normal pressure. Finally, the top cover of the vacuum integrated tank (3) is opened to take out the resin particle mixture that has been mixed evenly and degassed thoroughly in the sample preparation mold (4), and the experimental preparation process is completed.

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