CT Scan-Based In-Situ Loading Tensile Testing Device and Method for Particulate Materials

Abstract

This invention discloses an in-situ loading testing device and method for particulate matter based on industrial CT scanning, relating to the field of thermomechanics. The device includes a drive assembly, a sensor unit, a fixture assembly, a carbon fiber support cylinder, a heat insulation cylinder, a heating module, a gas filling and discharging system, and a sensor cooling and protection unit. The fixture assembly is surrounded by a heat insulation cylinder to form a sealed space, ensuring the sample can be tested in a specific gas atmosphere. Heating is achieved by heating the sample with a heating plate and introducing gas to uniformly heat it. A quick-connect water nozzle is connected to the top of the device, allowing connection to a water chiller for water cooling of the fixture assembly. The loading base is connected to the CT turntable using screw locking. This invention can fully simulate the thermomechanical changes of a particle bed under different thermal stresses and gas atmospheres. While heating and loading the sample, industrial CT scanning can be used to scan the loading process and internal microstructural changes of the sample in situ.

Description

Technical Field

[0001] This invention relates to the field of thermomechanics, and particularly to the field of material mechanical property testing and compatibility with industrial CT for monitoring the internal structure of materials. Specifically, it relates to an in-situ loading tensile testing device and method for particulate matter for CT scanning. Background Technology

[0002] Particulate matter is a system composed of a large number of discrete solid particles. It possesses the fluidity of fluids and the strong compressive strength of solids, thus finding wide application in industry. In the solid-state blanket design of fusion reactors, tritium breeders and neutron multipliers are typically present in particulate form within the blanket. These particles are accommodated using a mixed-filling method to form a pebble bed structure. These particles initially have a uniform size distribution and are randomly packed. This means that the surface of a single particle may be in contact with multiple adjacent particles, resulting in a very complex stress environment. Therefore, the stress distribution in the pebble bed exhibits significant non-uniformity, and particle breakage may occur due to unfavorable local stress conditions, leading to changes in the pebble bed structure.

[0003] Furthermore, in the field of materials mechanics analysis, traditional mechanical testing equipment only applies force to the sample to obtain relevant material data and macroscopic fracture phenomena; or the sample is simply studied under an industrial CT imaging system in its natural state to examine the internal structure of the material. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an in-situ loading testing device and method for particulate materials based on industrial CT scanning. This thermodynamic testing technique applies load and heat to the sample simultaneously under an industrial CT imaging system, allowing observation of internal structural changes and microscopic deformation damage under the combined influence of external force and temperature. It enables simultaneous performance testing and microstructural observation of materials, providing more comprehensive theoretical data for studying the forms of material structural deformation. This invention employs a gas-introducing heating method for the sample, using a circumferential heating approach, ensuring uniform heating and solving the heating problem for materials with low thermal conductivity. It can cover various sample material types. Furthermore, the sample support container is made of carbon fiber, which is X-ray transparent, facilitating clearer images obtained by industrial CT scanning. This invention provides a thermodynamic testing technique for dynamic monitoring of internal structural changes and microscopic deformation damage throughout the entire process under an industrial CT imaging system, offering comprehensive theoretical data for studying material failure modes.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An in-situ loading tensile testing device for particulate matter in CT scanning includes a drive assembly, a clamp assembly, a carbon fiber support cylinder, a heat insulation cylinder, a heating module, and a gas filling and discharging system. The drive assembly is integrated into a loading base. The clamp assembly is functionally divided into a tensile clamp and a loading head. The tensile clamp includes an upper tensile clamp and a lower tensile clamp, and the loading head includes an upper loading head and a lower loading head. The lower tensile clamp or lower loading head is connected to the loading base, and the upper tensile clamp or upper loading head is connected to an upper cover plate. The bottom of the upper cover plate has a guide hole for connecting a guide rod, and the upper part of the loading base has a guide hole for connecting the guide rod. The upper cover plate and the loading base are connected by guide holes to ensure the coaxiality of the upper and lower tensile clamps; the carbon fiber bearing cylinder is placed between the upper and lower pressure heads; a heat insulation cylinder is set outside the upper and lower tensile clamps or the upper and lower pressure heads to form a sealed whole; a gas inlet is welded to the top of the upper cover plate, and the gas inlet is connected to the gas filling and discharging system; both the top of the upper cover plate and the loading base are designed with water inlet and outlet ports, which are respectively connected to the water inlet pipe and water outlet pipe of the water chiller; the heating module heats the gas after it enters the heat insulation cylinder to heat the environment of the tensile or compression specimen.

[0007] Furthermore, the gas in the gas filling and discharging system is supplied by a gas source. The gas enters the gas inlet of the loading tensile testing device through a pressure reducing valve, a one-way valve, and a three-way valve. One end of the three-way valve is connected to a vacuum pump. The gas is heated to a specified temperature by a heating plate and enters the heat insulation cylinder to heat the compression or tensile specimen inside the carbon fiber bearing cylinder.

[0008] Furthermore, the tensile specimen is placed between the upper tensile fixture and the lower tensile fixture and fastened; two cuboid lugs are welded to the sides of the lower tensile fixture, and guide holes are provided in the cuboid lugs to insert guide rods to ensure the coaxiality and connection of the upper and lower tensile fixtures.

[0009] Furthermore, the bottom of the carbon fiber bearing cylinder is provided with a protrusion that is embedded in three recessed holes on the lower pressure head for positioning.

[0010] Furthermore, both the upper and lower tension clamps are provided with an O-ring groove on their sides, and an O-ring is installed in the O-ring groove. The upper tension clamp is nested inside the heat insulation cylinder and connected to form a sealed whole.

[0011] Furthermore, it also includes a sensor unit and a sensor cooling unit. The sensor cooling unit includes a water chiller and quick-connect water nozzles. The top of the upper cover plate is connected to two quick-connect water nozzles, which are the upper tension clamp water inlet and the upper tension clamp water outlet, respectively. The loading base is connected to two quick-connect water nozzles, which are the lower tension clamp water inlet and the lower tension clamp water outlet, respectively. The quick-connect water nozzles are respectively connected to the water outlet and water return of the water chiller.

[0012] Furthermore, the heating module includes a temperature control unit and a quick-connect heating wire connector; the quick-connect heating wire connector is used to connect the cable to power the heating plate; the temperature control unit is used to control the heating power of the heating plate and detect the temperature of the gas.

[0013] Furthermore, the heat insulation cylinder is divided into an upper heat insulation cylinder, a middle heat insulation cylinder, and a lower heat insulation cylinder; the upper heat insulation cylinder is connected to the upper cover plate and is used to install the upper tension clamp and the upper pressure head; the lower heat insulation cylinder is connected to the loading base and is used to install the lower tension clamp and the lower pressure head; the middle mounting cylinder is used to close the space for relative movement of the lower pressure head relative to the upper pressure head and the upper tension clamp relative to the lower tension clamp.

[0014] The present invention also provides a loading tensile testing method using the above-described particulate material in-situ loading tensile testing device for CT scanning, comprising the following steps:

[0015] Step 1: Before the experiment, power on the electrical control cabinet and turn on the control computer.

[0016] Step 2: Select the tension fixture and loading head according to the experimental objective;

[0017] Step 3: Connect the loading tensile testing device to the CT equipment;

[0018] Step 4: Connect the inlet and outlet of the water chiller to the quick-connect water nozzles respectively; connect one end of the heating cable and the signal transmission cable to the electrical control cabinet, and insert the other end of the heating cable into the heating cable quick-connect connector; connect the gas delivery pipe to the gas inlet to complete the preparations before the experiment.

[0019] Step 5: At the beginning of the experiment, the tensile testing device is evacuated; after evacuation is completed, the gas source is turned on and the pressure reducing valve is adjusted until the gas concentration reaches the standard.

[0020] Step 6: Set the required temperature according to the experimental requirements, and wait for the gas temperature to rise to the set temperature;

[0021] Step 7: After the temperature stabilizes, set the pressure required for the experiment;

[0022] Step 8: Clear the current force value to complete the force value reset to zero;

[0023] Step 9: Load the tensile or compression specimens according to the experimental requirements and scan them using CT equipment;

[0024] Step 10: After the scanning and loading or stretching process is completed, control the heating plate to stop heating; after the internal temperature of the loading tensile testing device has cooled down, disconnect the power supply of the control cabinet, disassemble the loading tensile testing device, take out the tensile or compression specimen, and end the experiment.

[0025] The advantages of this invention compared to existing technologies are:

[0026] (1) The present invention uses a method of heating the sample by introducing helium gas to perform a circumferential heating of the sample, which can make the sample heat evenly and solve the heating problem of materials with low thermal conductivity. It can cover a variety of sample material types.

[0027] (2) The sample carrier cylinder in this invention is made of carbon fiber, which can transmit X-rays, which is beneficial for industrial CT to obtain clearer images when scanning the sample.

[0028] (3) The present invention uses water cooling, which can ensure that the temperature of other components inside the host does not get too high while the temperature of the sample increases.

[0029] (4) According to different experimental requirements, the present invention can select appropriate fixture components to complete the tensile and loading test functions of the specimen in a set of loading tensile testing device.

[0030] In summary, this invention can be used to simulate the thermal stress environment of particles in a pellet bed. After applying a certain pressure and temperature to the pellets, the structure of the pellet bed and the distribution of broken particles after particle breakage are measured, revealing the thermomechanical properties of the pellet bed after particle breakage, and providing data support for the design and research of pellet beds.

[0031] Meanwhile, this invention can be integrated into an industrial CT turntable, and a certain load force and gas heating can be applied to the sample through this invention. At this time, the CT turntable can be rotated to scan and photograph the sample 360°, which helps to study the structural changes and micro-deformation damage principles of materials under stress and heating conditions, and reveal the thermodynamic behavior, fracture mechanism and thermomechanical properties of various samples and their relationship with load and material properties. Attached Figure Description

[0032] Figure 1 is a three-dimensional cross-sectional view of an in-situ loading tensile testing device for particulate matter used in CT scanning according to the present invention;

[0033] Figure 2 is a schematic diagram of the tensioning fixture structure;

[0034] Figure 3 is a schematic diagram of the system for the loading test experiment;

[0035] Figure 4a is a bottom view of the carbon fiber support cylinder;

[0036] Figure 4b is Figure 4a AA cross-section view;

[0037] Figure 5 is a front view of the stretched sample.

[0038] In the attached figures, the reference numerals are as follows: 1 is the drive assembly; 2 is the sensor unit; 3 is the loading base; 4 is the carbon fiber bearing cylinder; 5 is the upper pressure head; 6 is the lower pressure head; 7 is the heat insulation cylinder; 8 is the upper cover plate; 9 is the quick-connect water nozzle; 10 is the gas inlet; 11 is the quick-connect connector for the heating wire; 12 is the heating plate; 13 is the quick-release fixing base plate; 14 is the tensile specimen; 15 is the guide rod; 16 is the upper tensile clamp; 17 is the lower tensile clamp; 18 is the O-ring; 19 is the gas source; 20 is the pressure reducing valve; 21 is the one-way valve; 22 is the three-way valve; 23 is the vacuum pump; 24 is the water chiller; 25 is the gas control unit; 26 is the temperature control unit; 27 is the electrical control unit; 28 is the control computer host; 29 is the control computer monitor; 30 is the electrical control cabinet; 31 is the CT equipment; 32 is the locking screw; and 33 is the loading tensile testing device. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0040] like Figure 1 As shown, an in-situ loading tensile testing device for particulate matter in CT scanning according to the present invention includes a drive assembly 1, a sensor unit 2, a loading base 3, a clamp assembly, a carbon fiber bearing cylinder 4, a heat insulation cylinder 7, a heating plate 12, a gas filling and discharging system, a heating module, and a sensor cooling and protection unit.

[0041] The drive assembly 1 and sensor unit 2 are integrated into the loading base 3. The clamp assembly can be divided into a tension clamp and a loading head according to its function. The tension clamp can be divided into an upper tension clamp 16 and a lower tension clamp 17 according to its installation position, and the loading head can be divided into an upper pressure head 5 and a lower pressure head 6 according to its installation position. By changing the tension clamp and the loading head, the corresponding tension test and loading test can be performed. The sensor unit 2 is used to monitor the parameters of the cooling water.

[0042] During the loading experiment, particulate material was filled into the carbon fiber support cylinder 4, such as... Figure 4a , Figure 4bAs shown, the base of the carbon fiber bearing cylinder 4 has a boss, and the upper surface of the lower pressure head 6 has three round holes for positioning. Furthermore, the outer diameter of the upper pressure head 5 and the inner diameter of the carbon fiber bearing cylinder 4 can be replaced according to experimental needs. The uppermost part of the loading tensile testing device consists of a quick-connect water nozzle 9, a gas inlet 10, and a heating wire quick-connect connector 11. These three components are welded to the upper surface of the upper cover plate 8. The quick-connect water nozzle 9 is connected to the water chiller 24 inside the electrical control cabinet 30 via a rubber pipe. After the experiment begins, the water chiller 24 operates, controlling the coolant to circulate within the loading tensile testing device to cool the upper pressure head 5 and the lower pressure head 6, thus protecting the pressure heads in high-temperature environments. The gas inlet 10 is connected to the gas control unit 25 via a pipe. After the experiment begins, the gas control unit 25 controls the gas to enter the heating plate 12 through the gas inlet 10 for heating. The heating wire quick-connect connector 11 integrates the functions of power supply heating and signal transmission. The heating wire quick-connect connector 11 is connected to the temperature control unit 26 via wires and cables to power the heating plate 12. In addition, the signal line of the heat probe integrated in the loading tensile testing device is also connected to the temperature control unit 26 via the heating wire quick connector 11 for real-time monitoring of the internal temperature of the loading tensile testing device. The heating plate 12 is integrated inside the upper cover plate 8. The upper pressure head 5 is connected to the lower surface of the upper cover plate 8 via hexagonal screws. The lower pressure head 6 is quickly connected to the upper surface of the loading base 3 via hexagonal screws. The carbon fiber support cylinder 4 is placed on the upper part of the lower pressure head 6. In addition, both the upper pressure head 5 and the lower pressure head 6 have an O-ring groove designed on their sides for installing an O-ring rubber ring 18. The heat insulation cylinder 7 is located below the upper cover plate 8, which can surround the upper pressure head 5, the lower pressure head 6, and the carbon fiber support cylinder 4 in the middle, and form a sealed space with the O-ring rubber ring 18. The drive assembly 1 and the sensor unit 2 are both integrated inside the loading base 3. The quick-release mounting plate 13 is fixed to the CT equipment 31 with hexagonal screws. When scanning with the CT equipment 31, the loading tensile test device 33 can be placed on the quick-release mounting plate 13 and the position can be quickly fixed and installed by tightening the screws 32.

[0043] like Figure 2 As shown, the upper tensile clamp 16 is connected to the lower surface of the upper cover plate 8 by hexagonal screws, and the lower tensile clamp is installed on the upper part of the loading base by hexagonal screws. The guide rod 15 and the tensile specimen 14 are located in the middle of the upper tensile clamp 16 and the lower tensile clamp 17. In addition, both the upper tensile clamp 16 and the lower tensile clamp 17 are designed with an O-ring groove on their sides to install an O-ring rubber ring 18. A heat insulation cylinder 7 is provided to surround the upper tensile clamp 16, the lower tensile clamp 17, the tensile specimen 14 in the middle, and the guide rod 15, and to form a sealed space with the O-ring rubber ring 18. The sealed space can ensure that the specimen is loaded or stretched in a specific gas atmosphere, and different gas atmospheres can be achieved by changing different gas sources.

[0044] During the tensile test, the tensile specimen 14 needs to be installed between the upper tensile clamp 16 and the lower tensile clamp 17. Furthermore, both the upper and lower tensile clamps 16 and 17 have guide holes on their sides for inserting guide rods 15 to ensure coaxiality during the tensile process. The uppermost part of the loaded tensile testing device consists of a quick-connect water nozzle 9, a gas inlet 10, and a quick-connect heating wire connector 11. These three components are welded to the upper surface of the upper cover plate 8. The quick-connect water nozzle 9 is connected to the water chiller 24 inside the electrical control cabinet 30 via a rubber pipe. After the experiment begins, the water chiller operates, controlling the coolant to circulate within the loaded tensile testing device to cool the upper and lower tensile clamps 16 and 17, thus providing protection in high-temperature environments. The gas inlet 10 is connected to the gas control unit 25 via a pipe. After the experiment begins, the gas control unit 25 controls the gas to enter the heating plate through the gas inlet 10 for heating. The quick-connect heating wire connector 11 integrates the functions of power supply heating and signal transmission. It connects to the temperature control unit 26 via a wire or cable to power the heating plate 12. Furthermore, the signal line of the heat probe integrated within the tensile testing device is also connected to the temperature control unit 26 via the quick-connect heating wire connector 11 to monitor the internal temperature of the tensile testing device in real time. The heating plate 12 is integrated inside the upper cover plate 8.

[0045] like Figure 3 As shown, the gas filling and discharging system includes a gas source 19, a pressure reducing valve 20, a one-way valve 21, and a three-way valve 22. The heating method uses a heating plate 12 to heat the gas introduced to heat the sample. The advantage of this heating method is that it can make the internal sample temperature rise uniformly and can more accurately control the gas temperature. The gas enters the heating plate 12 through the gas inlet 10, and after being heated, it enters the heat insulation cylinder to uniformly heat the sample.

[0046] A pressure reducing valve 20 is installed at the outlet of gas source 19. The pressure reducing valve 20 controls the opening and closing of gas source 19 and regulates the outlet pressure. A one-way valve 21 is connected after the pressure reducing valve 20 to prevent gas backflow. A three-way valve 22 is connected after the one-way valve 21. One end of the three-way valve 22 is connected to the gas control unit 25, and the other end is connected to the vacuum pump 23. The vacuum pump is used to create a vacuum before the experimental preparation stage, ensuring a certain degree of vacuum inside the apparatus. The gas control unit 25 is used to control the gas flow rate and its circulation within the apparatus.

[0047] The temperature control unit 26 integrates the functions of controlling electric heating and heat signal processing, and is connected to the heating wire quick-connect connector 11 via wires and cables. The water chiller 24 controls the circulation of coolant within the tensile testing device, and is connected to the quick-connect water nozzle 9 via a rubber hose. Furthermore, the vacuum pump 23, water chiller 24, gas control unit 25, temperature control unit 26, electrical control unit 27, and control computer host 28 are all integrated within the electrical control cabinet 30 in a bottom-to-top installation order. The electrical control unit 27 is responsible for providing power to the other equipment within the cabinet. The control computer host 28 is connected to the control computer monitor 29, and controls the tensile testing device via control software.

[0048] Furthermore, the loading base 3 can be connected to the industrial CT turntable, that is, the loading tensile testing device 33 can be quickly connected to the CT equipment 31 by means of the quick-release fixed base plate 13.

[0049] Furthermore, the heat insulation cylinder 7 can be divided into three sections: an upper heat insulation cylinder for installing the upper tension clamp 16 and the upper pressure head 5; a lower heat insulation cylinder for installing the lower tension clamp 17 and the lower pressure head 6, which is connected to the loading base 3; and a middle mounting cylinder for sealing the space for relative movement of the lower pressure head 6 relative to the upper pressure head 5 and the upper tension clamp 16 relative to the lower tension clamp 17. During installation, the cylinders are fixedly connected from top to bottom.

[0050] Furthermore, such as Figure 5 As shown, the tensile specimen 4 is a symmetrical sector shape with a neck in the middle. The opening angle of the neck is 90 degrees, and the angle of the sector is 45 degrees ± 0.5 degrees. The tensile clamp for the tensile specimen 14 has a groove corresponding to the shape of the tensile specimen 14. After the tensile specimen 14 is placed in the groove, it can be tightened with screws. The loading head used in the loading experiment needs to be used with a specially made carbon fiber support cylinder 4. The diameter of the upper pressure head 5 is the same as the inner diameter of the carbon fiber support cylinder 4. The upper surface of the lower pressure head 6 has three round holes, which cooperate with the boss at the bottom of the carbon fiber support cylinder 4 for positioning. During the loading experiment, the particulate material fills the carbon fiber support cylinder 4 to form a particle bed. The lower pressure head 6 is driven upward by the drive component 1 to load the particle bed inside the carbon fiber support cylinder 4 by the upper pressure head 5 and the lower pressure head 6.

[0051] Furthermore, such as Figure 3 As shown, before the experiment begins, the entire system is evacuated using vacuum pump 23. Once the required vacuum level is reached, the gas source 19 is turned on, and the gas enters the gas inlet 10 of the loading tensile testing device through pressure reducing valve 20, one-way valve 21, and three-way valve 22. The gas is heated to the specified temperature in heating plate 12 and then enters the heat insulation cylinder 7 to uniformly heat the sample.

[0052] Furthermore, the heating module includes a temperature control unit 26, a heating wire quick-connect connector 11, and a heating plate 12. The top of the upper cover plate 8 is provided with a heating wire quick-connect connector 11 for connecting cables to provide power for heating; the temperature control unit 26 is used to control the temperature, control the heating power of the heating plate 12, and detect the gas temperature.

[0053] Furthermore, the sensor cooling protection unit includes a sensor unit 2, quick-connect water nozzles 9, and a water chiller 24. The upper end of the upper cover plate 8 has two quick-connect water nozzles 9, which are a cooling water inlet and a cooling water outlet, respectively connected to the water outlet and return water of the water chiller 24.

[0054] This invention also provides a loading tensile testing method for particulate matter in-situ loading testing device based on industrial CT scanning, which can observe the internal structure and microstructure of the sample under the combined influence of loading and heating using industrial CT, including the following steps:

[0055] Step 1: Before the experiment, power on the electrical control cabinet 30, turn on the power to the control computer 27, and open the loading system operation software and gas heating system software.

[0056] Step 2: Select the required tension fixture and loading head according to the experimental purpose.

[0057] Before installing the tensile specimen during the tensile test, the lower tensile clamp 17 must be moved upwards using the loading system operating software to provide sufficient space for subsequent installation of the clamps and specimen. An O-ring 18 is installed in the O-ring grooves of both the upper and lower tensile clamps 16 and 17. A heat insulation cylinder 7 is installed, and the screws of the lower tensile clamp 17 are mounted onto the loading base 3. One end of the tensile specimen 14 is bolted into the upper tensile clamp 16. Then, two guide rods 15 are inserted into the guide holes of the upper tensile clamp 16, and then the entire specimen is inserted into the guide holes of the lower tensile clamp 17. The lower end of the tensile specimen 14 is mounted to the lower tensile clamp 17 and secured with screws. The loading tensile testing device operating software is used to control the drive assembly 1 to move the lower tensile clamp 17 downwards, ensuring the bottom of the guide rods 15 fits against the loading base 3 and a seal is maintained.

[0058] During the loading experiment, before installing the compression specimen, the lower indenter 6 must be moved downwards using the operating software of the loading tensile testing device to leave sufficient space for the subsequent installation of the upper indenter 5 and the carbon fiber support cylinder 4. According to the test requirements, a suitable upper indenter 5 is selected, installed into the upper cover plate 8, and secured with screws. An O-ring 18 is installed in the O-ring groove of the upper indenter 5, and a heat insulation cylinder 7 is installed. The compression specimen is loaded into the carbon fiber support cylinder 4, and the carbon fiber support cylinder 4 is placed on the lower indenter 6. The heat insulation cylinder 7 and the upper indenter 5 are then installed as a whole onto the loading base 3. The operating software of the loading tensile testing device is operated to control the drive component 1 to move the lower indenter 6 upwards until the upper surface of the specimen inside the carbon fiber support cylinder 4 contacts the surface of the upper indenter 5.

[0059] Step 3: Connect the loading tensile testing device to the CT equipment 31. The bottom of the loading tensile testing device 33 has three locking screws 32 and a quick-release fixing base plate 13, which can facilitate the installation and removal of the loading tensile testing device and the CT equipment 31.

[0060] Step 4: Connect the inlet and outlet of the water chiller 24 to the quick-connect water nozzles 9, respectively. Connect one end of the heating cable and the signal transmission cable to the electrical control cabinet 30, and insert the other end of the cable into the heating cable quick-connect connector 11. Connect the gas delivery pipe to the gas inlet 10 to complete the preparations before the experiment.

[0061] Step 5: At the start of the experiment, evacuate the loading system. After evacuation, turn on the gas source 19 and adjust the pressure reducing valve 20 until the gas concentration reaches the standard.

[0062] Step 6: According to the test requirements, set the required temperature in the gas heating system software and wait for the gas temperature to rise to the set temperature.

[0063] Step 7: After the temperature stabilizes, set the required pressure for the experiment. If the required pressure is lower than the current system pressure, directly set the pressure value in the pressure setting section of the gas heating system software by clicking "Set". If the required pressure is higher than the current system pressure, manually adjust the system pressure at the pressure reducing valve 20 of the gas source 19.

[0064] Step 8: Clear the current force value in the gas heating system software to complete the force value reset to zero.

[0065] Step 9: Load the sample according to the experimental requirements and scan it using CT equipment 31.

[0066] Step 10: After the scanning and loading process is completed, control the heating plate 12 to stop heating. After the system cools down, disconnect the power supply to the electrical control cabinet 30, disassemble the loading tensile testing device, remove the tensile or compression specimen, and end the experiment.

[0067] The parts of this invention not described in detail are well-known in the art.

[0068] While the foregoing has described illustrative specific embodiments of the present invention to enable those skilled in the art to understand the invention, it should be understood that the invention is not limited to the scope of the specific embodiments. Various modifications that are obvious to those skilled in the art, provided they fall within the spirit and scope defined by the appended claims and the present invention, are all within the scope of protection of the present invention.

Claims

1. A particulate matter in-situ loading tensile testing device for CT scanning, characterized by: The device comprises a driving assembly, a clamp assembly, a carbon fiber bearing cylinder, a heat insulation cylinder, a heating module, and a gas charging and discharging system; when loading an experiment, particulate matter is filled in the carbon fiber bearing cylinder; the driving assembly is integrated in a loading base; the clamp assembly is divided into a tensile clamp and a loading pressure head according to functions; the tensile clamp comprises an upper tensile clamp and a lower tensile clamp, and the loading pressure head comprises an upper pressure head and a lower pressure head; the lower tensile clamp or the lower pressure head is connected with the loading base, and the upper tensile clamp or the upper pressure head is connected with an upper cover plate; the bottom of the upper cover plate is provided with a guide hole for connecting a guide rod, and the upper part of the loading base is provided with a guide hole, and the guide rod is connected with the upper cover plate and the loading base through the guide holes to ensure the coaxiality of the upper tensile clamp and the lower tensile clamp; the carbon fiber bearing cylinder is arranged between the upper pressure head and the lower pressure head; a heat insulation cylinder is arranged outside the upper tensile clamp and the lower tensile clamp or the upper pressure head and the lower pressure head to form a sealed whole; the top of the upper cover plate is welded with a gas inlet, and the gas inlet is connected with the gas charging and discharging system; the top of the upper cover plate and the loading base are both designed with water inlets and outlets, and the water inlets and outlets are respectively connected with water inlets and outlets of a water cooling machine; the heating module heats the gas after entering the heat insulation cylinder to heat the environment of the tensile sample or the compression sample. The heating module comprises a temperature control unit and a heating wire quick plug connector; the heating wire quick plug connector is used for connecting a cable to heat a disc; the temperature control unit is used for controlling the heating power of the disc and detecting the temperature of the gas; The gas in the gas charging and discharging system is provided by a gas source, and the gas enters the gas inlet of the loading tensile testing device through a pressure reducing valve, a one-way valve and a three-way valve, and one end of the three-way valve is connected with a vacuum pump; the gas is heated to a specified temperature by the disc, enters the heat insulation cylinder and heats the compression sample or the tensile sample in the carbon fiber bearing cylinder.

2. The particulate matter in-situ loading tensile test device for CT scanning of claim 1, wherein: The tensile sample is arranged between the upper tensile clamp and the lower tensile clamp and is fastened; the side surface of the lower tensile clamp is welded with two cuboid hanging ears, and the cuboid hanging ears are provided with guide holes for inserting the guide rod to ensure the coaxiality of the upper tensile clamp and the lower tensile clamp.

3. The particulate matter in-situ loading tensile test device for CT scanning of claim 1, wherein: The bottom of the carbon fiber bearing cylinder is provided with a protrusion embedded in three recesses on the lower pressure head for positioning.

4. The particulate matter in-situ loading tensile test device for CT scanning of claim 1, wherein: The side surface of the upper tensile clamp and the lower tensile clamp is provided with an O-ring groove, and an O-ring is installed in the O-ring groove; the upper tensile clamp and the lower tensile clamp are nested in the heat insulation cylinder to form a sealed whole.

5. The particulate matter in-situ loading tensile test device for CT scanning of claim 1, wherein: The device further comprises a sensor unit and a sensor cooling unit; the sensor cooling unit comprises a water cooling machine and quick plug water nozzles; the top of the upper cover plate is connected with two quick plug water nozzles, which are respectively the water inlet of the upper tensile clamp and the water outlet of the upper tensile clamp; the loading base is connected with two quick plug water nozzles, which are respectively the water inlet of the lower tensile clamp and the water outlet of the lower tensile clamp; the quick plug water nozzles are respectively connected with the water outlet and the return water of the water cooling machine.

6. The particulate matter in-situ loading tensile test device for CT scanning of claim 1, wherein: The heat insulation cylinder is divided into an upper heat insulation cylinder, a middle heat insulation cylinder and a lower heat insulation cylinder; the upper heat insulation cylinder is connected with the upper cover plate and is used for mounting the upper stretching clamp and the upper pressure head; the lower heat insulation cylinder is connected with the loading base and is used for mounting the lower stretching clamp and the lower pressure head; the middle heat insulation cylinder is used for closing the space of the relative movement of the lower pressure head relative to the upper pressure head and the upper stretching clamp relative to the lower stretching clamp.

7. A method for load stretch testing of particulate matter in-situ for CT scanning using the load stretch testing apparatus for particulate matter in-situ for CT scanning as claimed in any one of claims 1 to 6, wherein, The method comprises the following steps: Step 1: before the experiment, turn on the power of the electric control cabinet and open the power of the control computer; Step 2: select the stretching clamp and the loading pressure head according to the experimental purpose; Step 3: connect the loading stretching test device with the CT equipment; Step 4: connect the water inlet and outlet of the water cooler with the quick-insert water nozzle respectively; connect one end of the heating cable and the signal transmission cable with the electric control cabinet, insert the other end of the heating cable into the heating cable quick-insert connector; connect the gas delivery pipeline to the gas inlet, and complete the preparation before the experiment; Step 5: when the experiment starts, perform vacuumizing treatment on the loading stretching test device; after the vacuumizing is completed, open the gas source, adjust the pressure reducing valve until the gas concentration reaches the standard; Step 6: set the required temperature according to the test requirement, and wait for the gas temperature to rise to the set temperature; Step 7: after the temperature is stable, set the required pressure for the experiment; Step 8: clear the current force value and complete the zeroing of the force value; Step 9: load the stretching sample or the compression sample according to the experimental requirement and use the CT equipment to scan; Step 10: after the scanning and loading or stretching process is completed, stop heating the heating disc; after the inside of the loading stretching test device is cooled, disconnect the power of the electric control cabinet, disassemble the loading stretching test device, take out the stretching sample or the compression sample, and end the experiment.

8. The method of claim 7, wherein the load tensile test method is characterized by, The step 2 comprises: When performing the stretching experiment, before installing the stretching sample, control the upper stretching clamp to move upward; install an O-shaped rubber ring in the O-shaped ring groove of the upper stretching clamp and the lower stretching clamp, set the heat insulation cylinder, and install the lower stretching clamp on the loading base; install one end of the stretching sample in the upper stretching clamp; then insert the two guide rods into the guide holes of the upper stretching clamp and then integrally insert them into the guide holes of the lower stretching clamp; install and fix the lower end of the stretching sample with the lower stretching clamp; set the lower stretching clamp to run downward, so that the bottom of the guide rod is attached to the loading base and the sealing is ensured; When performing the loading experiment, before installing the compression sample, control the lower pressure head to move downward; according to the test requirement, select the upper pressure head to be installed in the upper cover plate and fastened; install an O-shaped rubber ring in the O-shaped ring groove of the upper pressure head, and set the heat insulation cylinder; load the compression sample in the carbon fiber bearing cylinder, and place the carbon fiber bearing cylinder on the lower pressure head; then integrally install the heat insulation cylinder and the upper pressure head on the loading base; set the lower pressure head to run upward until the upper surface of the sample in the carbon fiber bearing cylinder is in contact with the surface of the upper pressure head.

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