A temperature calibration method for centrifuge in-situ heating under high speed and high temperature

Abstract

The application discloses a kind of high-speed centrifuge in-situ heating under high temperature of high speed effect temperature calibration test method.Determine the parameters of centrifuge and test sample, install a temperature calibration sample and multiple test samples in sample chuck and insert thermocouple;In the case of not starting centrifuge, keep still, vacuum control temperature system controls inductive heating system, circulating water cooling system work to test sample and temperature calibration sample to apply temperature load, after temperature reaches predetermined temperature and keeps temperature;Analysis and processing obtain the parameters of upper and lower induction coils when formal test measurement;Remove temperature calibration sample, replace test sample, start the main shaft rotation of centrifuge again and reach speed, control according to the parameters obtained in the fifth step until test sample is pulled off and broken.The application solves the deficiency that current high-speed radiation heating can only check ambient temperature but cannot accurately check sample temperature under high speed, and can directly check sample temperature under high speed, so that the temperature of test component is more accurate.

Description

Technical Field

[0001] This invention relates to a centrifuge heating temperature calibration control method in the field of in-situ heating of metallic materials, and more particularly to a temperature calibration test method for in-situ centrifuge heating of metallic materials under high speed and high temperature. Background Technology

[0002] National standards GB / T 38822-2020 "Metallic Materials Creep-Fatigue Test Methods" and GB / T 6825.1-2008 "Inspection of Static Uniaxial Testing Machines - Part 1: Inspection and Calibration of Force Measuring Systems for Tensile and / or Compressive Testing Machines" both specify test methods for the mechanical properties of metallic materials. However, the test environment specified in these standards is 1G (G=9.8m / s²). 2 This can satisfy the research on the mechanical properties of metallic materials themselves. However, in turbine propulsion systems, such as aero-engines, space engines, industrial and marine gas turbines, and turbochargers for automobiles and trains, key components of the power system, such as compressor blades, fan blades, and turbine blades, are all in a high-speed rotating state during normal operation, that is, the service environment is usually a centrifugal hypergravity environment.

[0003] A turbine propulsion system is typically a turbine power unit that converts the thermal energy from fuel combustion into mechanical energy by using guide vanes to drive a turbine through thermal expansion. A turbocharger, for example, utilizes the exhaust gases from a diesel (gasoline) engine to convert engine waste heat into mechanical energy through thermal expansion on a turbine. During service, the turbine blades of these power units rotate at high speed around the engine axis. Their function is to convert the potential and thermal energy of the combustion gases into mechanical work for the rotor through combustion gas expansion. Therefore, the turbine blades bear loads including aerodynamic forces, centrifugal forces, and thermal loads during service. Centrifugal force, generated by high-speed rotation, is a volume force that primarily causes radial tensile stress on the blades. For blades with torsional structures, it also generates torsional stress. If the blade's overlap line does not perfectly coincide with the radial line, the centrifugal force also causes bending stress. The thermal stress generated by the thermal load is closely related to the blade's temperature gradient and geometric constraints; the greater the temperature gradient, the greater the thermal stress. However, the key material mechanical property data currently used for designing turbine blades in turbine propulsion systems all come from testing standard specimens under static, uniaxial stress states using 1G-based endurance, creep, and fatigue testing machines. While the mechanical property data from standard specimens can provide a design basis for the strength design of turbine blades in turbine propulsion systems to some extent, the complex geometry of the blades and their complex stress states differ from those of standard specimens. The material mechanical property data obtained from standard specimens do not consider the impact of high speeds and blade geometry on structural reliability and cannot be directly used to assess the lifespan of turbine blades. Summary of the Invention

[0004] To address the shortcomings of current static mechanical property testing of metallic materials at 1G speeds, and the lack of suitable in-situ heating and temperature calibration methods for testing the mechanical properties of metallic materials under high rotational speed and high temperature conditions, this invention provides an in-situ heating and temperature calibration method for metallic materials under high-speed rotational conditions. This solves the key challenges of in-situ heating, temperature verification, and intelligent temperature control in the mechanical property testing process of metallic materials under high rotational speed and high temperature conditions.

[0005] The in-situ heating of metal materials under high rotation speed environment described in this invention refers to the process in which the test material or component rotating at high speed is always in an in-situ heating state until the test is completed.

[0006] The temperature verification of the in-situ heating system for metal materials under high-speed rotation described in this invention refers to the in-situ temperature measurement and calibration of the temperature distribution of the test material or component in a high-speed rotating or stationary state during the mechanical property testing of metal materials or components.

[0007] The high temperature mentioned in this invention refers to a heating temperature of not less than 500°C applied to a designated area of ​​the sample during the experiment, and the duration of in-situ heating is not less than the test time.

[0008] The high speed mentioned in this invention refers to a centrifuge speed of not less than 5000 rpm during the experiment.

[0009] The technical solution adopted in this invention is as follows:

[0010] Step 1: Determine the spindle speed and impeller radius of the centrifuge based on the experimental conditions;

[0011] Step 2: Determine the size and weight of the mass block, the size of the gauge length, and the geometric center of the test specimen;

[0012] Step 3: Determine the test temperature and the centrifugal stress applied to the geometric center of the gauge length, and then determine the rotational speed corresponding to the centrifugal stress at the geometric center of the gauge length, and determine the distance between the geometric center of the gauge length and the center of the centrifuge spindle;

[0013] Step 4: Install a temperature calibration sample in one slot of the sample chuck and test samples in the remaining slots. Install the temperature calibration sample next to the test sample. Insert thermocouples into each thermocouple hole of the temperature calibration sample and fix temperature control thermocouples at the geometric center of the gauge length of both the test sample and the temperature calibration sample.

[0014] Step 5: Without starting the centrifuge, keep the sample chuck and the test sample and temperature calibration sample on it stationary, evacuate the environment, and then start the induction heating system, circulating water cooling system and temperature control system. The temperature control system controls the operation of the induction heating system and circulating water cooling system to apply temperature load to the test sample and temperature calibration sample. After the temperature reaches the predetermined temperature, keep it at that temperature for a period of time.

[0015] The temperature data obtained by measuring the temperature of the temperature control thermocouples of the test sample and the temperature calibration sample, as well as the thermocouples in each thermocouple hole of the temperature calibration sample, are analyzed and processed to obtain the parameters of the current flowing through the upper and lower induction coils, the current alternation frequency, and the distance between the upper and lower induction coils during the formal test measurement.

[0016] Step 6: Remove the temperature calibration sample from the sample chuck slot, replace it with the test sample, and then start the centrifuge. Rotate the centrifuge spindle to the speed corresponding to the centrifugal stress to conduct the formal test. Control the distance between the upper and lower induction coils, the current and the alternating frequency of the current according to the parameters obtained in Step 5, and keep the parameters unchanged until the test sample is pulled apart and breaks.

[0017] The method employs a temperature calibration testing device, which includes a sample chuck, an induction heating system, a circulating water cooling system, and a temperature control system. The sample chuck is coaxially mounted on the main shaft of a centrifuge and rotates synchronously with the main shaft. The test sample and the temperature calibration sample are mounted on the sample chuck. The induction heating system is coaxially mounted on the centrifuge and does not rotate with the main shaft. The induction heating system and the circulating water cooling system are connected. The temperature control system is connected to both the circulating water cooling system and the test sample.

[0018] The sample chuck includes a chuck body, slots, and flanges. Flanges are coaxially mounted at both ends of the center of the chuck body. The chuck body is coaxially fixedly connected to the main shaft of the centrifuge through the flanges. Multiple slots are circumferentially arranged around the chuck body, and each slot is used to install a test sample.

[0019] The test specimen is strip-shaped and includes a mass block, a gauge section, a load-bearing section, and an assembly tenon connected in sequence. The mass block, gauge section, load-bearing section, and assembly tenon are arranged sequentially along the strip shape of the test specimen, and the assembly tenon is fitted into the slot of the sample chuck.

[0020] The calibration sample and the test sample have the same structure, shape and size. The difference is that the calibration sample has multiple thermocouple holes of different depths inside. Each thermocouple hole is arranged radially along the sample chuck body and each thermocouple hole is equipped with a thermocouple.

[0021] The induction heating system includes an upper induction coil, an upper fixing plate, a lower induction coil, and a lower fixing plate; the upper fixing plate and the lower fixing plate are fixedly arranged parallel to each other at intervals, and a sample chuck is arranged in the interval between the upper fixing plate and the lower fixing plate; the annular upper induction coil and the lower induction coil are fixed to the bottom surface of the upper fixing plate and the top surface of the lower fixing plate through the upper induction coil insulation layer and the lower induction coil insulation layer, respectively.

[0022] The upper induction coil and the lower induction coil are respectively encased in the inner cavity of the upper induction coil insulation layer and the lower induction coil insulation layer. The inner cavities of the upper induction coil insulation layer and the lower induction coil insulation layer are connected by a pipe. The upper induction coil insulation layer and the lower induction coil insulation layer are respectively fixed to the bottom surface of the upper fixing plate and the top surface of the lower fixing plate by the upper fixing screw and the lower fixing screw.

[0023] The circulating water cooling system includes a piping assembly installed in the induction heating system, as well as a flow inlet pipe, a flow outlet pipe, a positive electrode, an inner insulating sleeve, a metal sleeve, a negative electrode, a copper pipe, a first insulating sleeve, a fixed flange, a second insulating sleeve, a clamping nut, a seal, an electrode insulating sleeve, an external outlet pipe, an external positive electrode plate, an external inlet pipe, and an external negative electrode plate. A first insulating sleeve for insulation from the metal sleeve is fitted over the copper pipe, and a metal sleeve is fitted over the first insulating sleeve. The middle part of the metal sleeve is sealed in the center hole of the fixed flange by the second insulating sleeve and a shaft sealing ring. The fixed flange is fixed to the experimental chamber cover of the centrifuge. The two ends of the copper pipe, the first insulating sleeve, and the metal sleeve are fixed and sealed by the inner insulating sleeve and the seal, respectively. One end of the copper pipe passes through the inner insulating sleeve and is coaxially connected to the flow outlet pipe, and passes through... A positive electrode is installed at the end after the inner insulating sleeve; the external positive electrode plate is electrically connected to the copper tube through the electrode insulating sleeve, so that the positive electrode is directly connected to the external positive electrode plate after passing through the copper tube; the other end of the copper tube is connected to the external water outlet pipe, so that the water outlet pipe flows directly through the copper tube and the external water outlet pipe; there is an annular pipe gap between the first insulating sleeve and the metal sleeve to serve as a water inlet channel, one end of the water inlet channel is connected to the water inlet pipe through the metal pipe, and a negative electrode is installed near the end of the water inlet pipe; the external negative electrode plate is electrically connected to the metal sleeve through the tightening round nut, so that the negative electrode is connected to the external negative electrode plate after passing through the metal pipe and the metal sleeve in sequence; a through groove is opened on the pipe wall at one end of the metal sleeve that connects to the sealing element, and the through groove is connected to the external water inlet pipe in sequence, so that the water inlet pipe flows through the metal pipe, the water inlet channel, and the through groove in sequence before flowing through the external water inlet pipe.

[0024] The pipeline assembly includes a heating inlet pipe, an inlet pipe sealing sleeve, a heating outlet pipe, and an outlet pipe sealing sleeve. One end of the heating inlet pipe and the heating outlet pipe are connected to the inlet pipe sealing sleeve and the outlet pipe sealing sleeve, respectively, and to the flow inlet pipe and the flow outlet pipe. The other end of the heating inlet pipe and the heating outlet pipe are respectively connected to the inner cavity environment where the upper induction coil and the lower induction coil are located in the induction heating system. The inner cavity environments where the upper induction coil and the lower induction coil are located are interconnected.

[0025] The external water outlet pipe and the external water inlet pipe are respectively connected to the water inlet and water outlet of the circulating water machine.

[0026] The positive and negative electrodes are electrically connected to the upper and lower induction coils, respectively, and the external positive and negative electrode plates are connected to the positive and negative terminals of an external power supply, respectively.

[0027] The temperature control system includes thermocouples, thermocouple extension lines, high-speed slip rings, a data acquisition module, a data conversion and transmission module, and a high-frequency AC power supply cabinet. Thermocouples are fixed on the test sample surfaces corresponding to the upper and lower induction coils of the induction heating system. Thermocouples are connected via thermocouple extension lines, high-speed slip rings, and the data acquisition module. The data acquisition module is communicatively connected to the high-frequency AC power supply cabinet via the data conversion and transmission module. The high-frequency AC power supply cabinet is electrically connected to the external positive electrode plate and external negative electrode plate of the circulating water cooling system.

[0028] Because the heating system heats the specimen through induction, the outer surface temperature of the specimen will be higher than the internal temperature, resulting in a yielding effect. The temperature inside the specimen is low and the temperature outside is high. This uneven temperature distribution throughout the specimen greatly reduces the effectiveness of the specimen test and increases the test error.

[0029] To avoid such problems, the present invention designs a temperature calibration device and a temperature calibration process. The temperature calibration device and the temperature calibration process ensure that the test sample can be heated evenly during the formal test, and the temperature at each part reaches the preset temperature with an error of no more than five degrees Celsius.

[0030] The temperature calibration of this invention can ensure that the temperature of the specimen is uniform and without gradient along the direction perpendicular to the centrifugal force, while the temperature along the direction of the centrifugal force can be non-uniform and have a gradient.

[0031] The beneficial effects of this invention are:

[0032] (1) The present invention solves the problem that radiation heating at high speed can only verify the ambient temperature but cannot accurately verify the sample temperature. The temperature calibration test method provided by the present invention can directly verify the sample temperature at high speed, making the temperature of the test component more accurate.

[0033] (2) By changing the shape of the test sample and the spacing and depth of the temperature calibration thermocouples, the temperature of any position of the test sample can be checked as needed. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the sample chuck 1.

[0035] Figure 2 This is a schematic diagram of the structure of test sample 1.1;

[0036] Figure 3 This is a schematic diagram of the structure of induction heating system 2;

[0037] Figure 4 This is a schematic diagram of the circulating water cooling system 3;

[0038] Figure 5 This is a schematic diagram of temperature control system 4;

[0039] Figure 6 This is a schematic diagram of the structure of test sample 1.1;

[0040] Figure 7 This is a schematic diagram of the structure of test sample 1.1;

[0041] Figure 8 This is a schematic diagram of the structure of test sample 1.1;

[0042] Figure 9 This is a schematic diagram of the installation of sample chuck 1 and induction heating system 2 on a centrifuge;

[0043] Figure 10 This is a process route diagram for the specific implementation of heating;

[0044] Figure 11 This is the process route diagram for heating implementation two;

[0045] Figure 12 This is the process route diagram for the third specific implementation of heating;

[0046] Figure 13 This is a schematic diagram of the structure of temperature calibration sample 5;

[0047] Figure 14 This is a layout diagram of the test sample 1.1, temperature calibration sample 5, sample chuck 1, and induction heating system 2 after they are installed together.

[0048] In the picture:

[0049] Sample chuck 1: Test specimen 1.1, chuck slot 1.2, flange 1.3;

[0050] Mass block 1.1.1, gauge section 1.1.2, load-bearing section 1.1.3, assembly tenon 1.1.4;

[0051] Induction heating system 2: 2.1 Upper induction coil, 2.2 Upper induction coil insulation layer, 2.3 Upper fixing plate, 2.4 Upper fixing screw, 2.5 Lower induction coil, 2.6 Lower induction coil insulation layer, 2.7 Lower fixing plate, 2.8 Lower fixing screw, 2.9 Connecting rod, 2.10 Nut, 2.11 Heating water inlet pipe, 2.12 Water inlet pipe sealing sleeve, 2.13 Heating water outlet pipe, 2.14 Water outlet pipe sealing sleeve;

[0052] Circulating water cooling system 3: Flow inlet pipe 3.1, first connecting nut 3.2, flow outlet pipe 3.3, second connecting nut 3.4, positive electrode 3.5, inner insulating sleeve 3.6, negative electrode 3.8, copper pipe 3.9, first insulating sleeve 3.10, fixing flange 3.11, fixing screw 3.12, shaft sealing ring 3.13, second insulating sleeve 3.14, clamping round nut 3.15, tightening nut 3.16, insulating component 3.17, sealing component 3.18, electrode insulating sleeve 3.19, sealing nut 3.20, external outlet pipe 3.21, external positive electrode plate 3.22, external inlet pipe 3.23, and external negative electrode plate 3.24;

[0053] Temperature control system 4: thermocouple 4.1, thermocouple extension cable 4.2, high-speed slip ring 4.3, data acquisition module 4.4, control software 4.5, data conversion and transmission module 4.6, high-frequency AC power supply cabinet 4.7;

[0054] Temperature calibration sample 5: thermocouple hole 5-1, thermocouple hole 5-2, thermocouple hole 5-3, thermocouple hole 5-4, thermocouple hole 5-5, thermocouple hole 5-6, thermocouple hole 5-7. Detailed Implementation

[0055] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0056] like Figure 9 As shown, a temperature calibration test device was designed in the specific implementation. The device includes a sample chuck 1, an induction heating system 2, a circulating water cooling system 3, and a temperature control system 4. The sample chuck 1 is coaxially mounted on the main shaft of the centrifuge and rotates synchronously with the main shaft of the centrifuge. The test sample 1.1 and the temperature calibration sample 5 are mounted on the sample chuck 1. The induction heating system 2 is coaxially mounted on the centrifuge and remains fixed without rotating with the main shaft of the centrifuge. The induction heating system 2 is connected to the circulating water cooling system 3. The temperature control system 4 is connected to the circulating water cooling system 3 and the test sample 1.1 respectively.

[0057] The centrifuge is a supergravity centrifuge.

[0058] like Figure 1As shown, the sample chuck 1 is used to install test samples and is connected to the centrifuge via the main shaft. It includes a chuck body, slots 1.2 and flanges 1.3. The flanges 1.3 are coaxially fixed at both ends of the center of the chuck body. The chuck body is coaxially fixedly connected to the main shaft of the centrifuge via the flanges 1.3. Multiple slots 1.2 are circumferentially arranged around the chuck body. The multiple slots 1.2 are spaced apart circumferentially. Each slot 1.2 is used to install one test sample 1.1.

[0059] Flange 1.3 is used to connect sample chuck 1 to centrifuge spindle. During the experiment, the high-speed rotation of centrifuge spindle drives sample chuck 1 to rotate, thereby applying centrifugal load to test sample 1.1.

[0060] The slot 1.2 is mainly used to fix the high-speed rotating test specimen 1.1. The mounting tenon 1.1.4 of the test specimen 1.1 is installed in the slot 1.2, so that the sample chuck 1 drives the test specimen 1.1 to rotate together when it rotates.

[0061] like Figure 2 As shown, the test specimen 1.1 is made of a metal material used for testing performance and is strip-shaped. It includes a mass block 1.1.1, a reference segment 1.1.2, a load-bearing segment 1.1.3, and an assembly tenon 1.1.4 connected in sequence. The mass block 1.1.1, reference segment 1.1.2, load-bearing segment 1.1.3, and assembly tenon 1.1.4 are all arranged sequentially along the strip shape of the test specimen 1.1. Specifically, the mass block 1.1.1, reference segment 1.1.2, load-bearing segment 1.1.3, and assembly tenon 1.1.4 are arranged radially outward from the slot 1.2 of the sample chuck 1, and the assembly tenon 1.1.4 is fitted into the slot 1.2 of the sample chuck 1.

[0062] In the specific implementation, the width of the tenon 1.1.4 and the groove width of the chuck 1.2 of the sample chuck 1 are both greater than the width of the mass block 1.1.1, the gauge section 1.1.2 and the load-bearing section 1.1.3, so that the test specimen 1.1 can be stably embedded and positioned when it is driven to rotate at high speed by the sample chuck 1.

[0063] Mass block 1.1.1 is used to apply a centrifugal stress to the standard moment section 1.1.3 through the centrifugal force generated by its own weight at high speeds. The mass of mass block 1.1.1 is m, its effective radius is r, and its rotational speed is ω. Therefore, the centrifugal force F generated by mass block 1.1.1 is F = mrω. 2 The weight m of mass block 1.1.1 depends on the fracture strength of the material under experimental conditions.

[0064] Gauge segment 1.1.2 is connected to mass block 1.1.1 and is used to bear the centrifugal stress and thermal stress loads applied by mass block 1.1.1 under high-speed rotation and high temperature. The shape of gauge segment 1.1.2 can be changed according to actual needs.

[0065] The load-bearing section 1.1.3 is used to connect the gauge section 1.1.2 and the assembly tenon 1.1.4.

[0066] According to experimental requirements, test sample 1.1 can be designed as follows: Figure 2 , Figures 6-8 The structure.

[0067] like Figure 13 As shown, the temperature calibration sample 5 and the test sample 1.1 have the same structure, shape and size. The difference is that the temperature calibration sample 5 has multiple thermocouple holes of different depths inside. Each thermocouple hole is arranged radially along the sample chuck 1, and each thermocouple hole is equipped with a thermocouple.

[0068] In practice, the temperature calibration sample 5 has thermocouple holes 5-1, 5-2, 5-3, 5-4, 5-5, 5-6, and 5-7 of different depths on the outer end face of the sample chuck 1 along the radial direction of the sample body. Each thermocouple hole is fitted with a thermocouple, which is inserted into the bottom of the thermocouple hole.

[0069] To verify the temperatures at sections A, B, C, D, E, F, and G on the calibration sample 5, thermocouple holes 5-1, 5-2, 5-3, 5-4, 5-5, 5-6, and 5-7 are drilled on the sample 5, corresponding to sections A, B, C, D, E, F, and G, respectively. During verification, thermocouples are inserted into thermocouple holes 5-1, 5-2, 5-3, 5-4, 5-5, 5-6, and 5-7, respectively, and then the thermocouples are connected to the temperature control system 4. The number and depth of the thermocouple holes can be adjusted during the actual experiment.

[0070] The center of the gauge length 1.1.2 of test specimen 1.1 and temperature calibration specimen 5 is provided with one or both of a thermocouple and a strain gauge.

[0071] like Figure 3As shown, the induction heating system 2 is used to heat the high-speed rotating sample in situ, applying a temperature load to a designated area of ​​the test sample 1.1. It includes an upper induction coil 2.1, an upper fixing plate 2.3, a lower induction coil 2.5, and a lower fixing plate 2.7. The upper fixing plate 2.3 and the lower fixing plate 2.7 are fixedly arranged parallel to each other at intervals. In practice, the centrifuge spindle rotatably passes through the upper fixing plate 2.3. A sample chuck 1 is arranged in the gap between the upper fixing plate 2.3 and the lower fixing plate 2.7. The upper fixing plate 2.3 and the lower fixing plate 2.7 are supported and fixed by a connecting rod 2.9, with a nut 2.10 installed at the outer end of the connecting rod 2.9. The annular upper induction coil 2.1 and lower induction coil 2.5 are fixed to the bottom surface of the upper fixing plate 2.3 and the top surface of the lower fixing plate 2.7 by the upper induction coil insulation layer 2.2 and the lower induction coil insulation layer 2.6, respectively.

[0072] Both the upper fixing plate 2.3 and the lower fixing plate 2.7 are annular plates, and both the upper induction coil 2.1 and the lower induction coil 2.5 are integral annular coils.

[0073] Specifically, the upper induction coil 2.1 and the lower induction coil 2.5 are respectively encased in the inner cavities of the upper induction coil insulation layer 2.2 and the lower induction coil insulation layer 2.6. The inner cavities of the upper induction coil insulation layer 2.2 and the lower induction coil insulation layer 2.6 are connected by a pipe. The upper induction coil insulation layer 2.2 and the lower induction coil insulation layer 2.6 are respectively fixed to the bottom surface of the upper fixing plate 2.3 and the top surface of the lower fixing plate 2.7 by the upper fixing screw 2.4 and the lower fixing screw 2.8.

[0074] The upper induction coil 2.1 is wrapped inside the upper induction coil insulation layer 2.2 to prevent conductivity and for insulation purposes. Then, the upper induction coil 2.1 with the insulation layer is fixed to the upper fixing plate 2.3 by the upper fixing screw 2.4 to form the upper induction coil. The lower induction coil 2.5 is wrapped inside the lower induction coil insulation layer 2.6 and is also fixed to the lower fixing plate 2.7 by the lower fixing screw 2.8 to form the lower induction coil. Subsequently, the upper fixing plate 2.3 and the lower fixing plate 2.7 are assembled together by the connecting rod 2.9 and the nut 2.10.

[0075] When an alternating current is applied, the metal material placed between the upper induction coil 2.1 and the lower induction coil 2.5 generates an induced current I or eddy current under the action of the alternating magnetic field. The eddy current generates heat through a resistive conductor, and then heats the metal material through thermal conduction. The Joule heat Q generated by the induced current I is I. 2 RtR is the resistance of the metallic material, and t is time. During induction heating, the heating temperature is controlled by adjusting the AC frequency f, the distance between the sample and the upper induction coil 2.1 and the lower induction coil 2.5, and the heating power.

[0076] like Figure 4 As shown, the function of the circulating water cooling system 3 is to cool the copper tubes in the upper induction coil 2.1 and the lower induction coil 2.5 in the induction heating system 2. It includes a piping assembly installed in the induction heating system 2, as well as a flow inlet pipe 3.1, a flow outlet pipe 3.3, a positive electrode 3.5, an inner insulating sleeve 3.6, a metal sleeve 3.7, a negative electrode 3.8, a copper tube 3.9, a first insulating sleeve 3.10, a fixed flange 3.11, a second insulating sleeve 3.14, a clamping nut 3.15, a seal 3.18, an electrode insulating sleeve 3.19, an external outlet pipe 3.21, an external positive electrode plate 3.22, an external inlet pipe 3.23, and an external negative electrode plate 3.24.

[0077] A first insulating sleeve 3.10 and a metal sleeve 3.7 are coaxially fitted outward from the outer radial direction of the copper tube 3.9. The first insulating sleeve 3.10, which is used to insulate against the metal sleeve 3.7, is fixedly and coaxially fitted outside the copper tube 3.9. The metal sleeve 3.7 is coaxially fitted outside the first insulating sleeve 3.10, thus maintaining insulation between the copper tube 3.9 and the metal sleeve 3.7. The middle part of the metal sleeve 3.7 is sealed in the center hole of the fixed flange 3.11 through the second insulating sleeve 3.14 and the shaft sealing ring 3.13. The fixed flange 3.11 is fixed to the experimental chamber cover of the centrifuge by the fixing screw 3.12. The two ends of the copper tube 3.9, the first insulating sleeve 3.10 and the metal sleeve 3.7 are fixed and sealed by the inner insulating sleeve 3.6 and the sealing element 3.18, respectively, which provide insulation and prevent water leakage.

[0078] One end of the copper pipe 3.9 passes through the inner insulating sleeve 3.6 and is coaxially connected to the water outlet pipe 3.3. A positive electrode 3.5 is installed at the end of the copper pipe 3.9 after passing through the inner insulating sleeve 3.6. An external positive electrode plate 3.22 is electrically connected to the copper pipe 3.9 through multiple electrode insulating sleeves 3.19. Specifically, at least two electrode insulating sleeves 3.19 are threaded onto the external threads of the copper pipe 3.9. An external positive electrode plate 3.22 is pressed between two adjacent electrode insulating sleeves 3.19. The external positive electrode plate 3.22 passes through the gap between two adjacent electrode insulating sleeves 3.19 and is electrically connected to the external positive electrode plate 3.22. This allows the positive electrode 3.5 to be directly electrically connected to the external positive electrode plate 3.22 via the copper pipe 3.9.

[0079] The other end of the copper pipe 3.9 is connected to the external water outlet pipe 3.21 via the sealing nut 3.20, so that the water outlet pipe 3.3 can flow directly through the copper pipe 3.9 and the external water outlet pipe 3.21;

[0080] An annular pipe gap exists between the first insulating sleeve 3.10 and the metal sleeve 3.7 to serve as a water inlet channel. The water inlet channel is connected to a flow-through water inlet pipe 3.1 at one end near the inner insulating sleeve 3.6 via a metal pipe. A negative electrode 3.8 is positioned near the end of the flow-through water inlet pipe 3.1. An external negative electrode plate 3.24 is electrically connected to the metal sleeve 3.7 via multiple clamping round nuts 3.15. Specifically, at least two clamping round nuts 3.15 are threaded onto the external threads of the metal sleeve 3.7. An external negative electrode plate 3.24 is clamped between adjacent clamping round nuts 3.15, and the external negative electrode plate 3.24 passes through the gap between adjacent clamping round nuts 3.15 to maintain electrical connection. This allows the negative electrode 3.8 to be electrically connected to the external negative electrode plate 3.24 after sequentially passing through the metal pipe and the metal sleeve 3.7.

[0081] The metal sleeve 3.7 has a through groove on the end wall between the external positive electrode plate 3.22 and the external negative electrode plate 3.24 connected to the sealing element 3.18. The through groove is connected to the external water inlet pipe 3.23. Specifically, an insulating element 3.17 is fitted on the metal sleeve 3.7 around the through groove by a tightening nut 3.16. The external water inlet pipe 3.23 passes through the through hole and the through groove on the insulating element 3.17. This allows the water inlet pipe 3.1 to flow through the metal pipe, the water inlet channel, the through groove, and then to the external water inlet pipe 3.23.

[0082] More specifically, copper tube 3.9 is a hollow long copper tube with a first insulating sleeve 3.10 installed on its outer circumference for insulation, and a sealing ring installed to prevent air leakage from the experimental chamber.

[0083] The inlet pipe 3.1 is connected to the heating inlet pipe 2.11 of the induction heating system 2 via the first connecting nut 3.2; the outlet pipe 3.3 is connected to the heating outlet pipe 2.13 of the induction heating system 2 via the second connecting nut 3.4; the positive electrode 3.5 is installed on the outer periphery of the outlet pipe 3.3 to ensure that the cooling water can cool the positive electrode 3.5; the negative electrode 3.8 is installed on the outer periphery of the inlet pipe 3.1 to ensure that the cooling water can cool the negative electrode 3.8.

[0084] The metal sleeve 3.7 is installed on the chamber cover of the experimental chamber via a flange 3.11 using six fixing screws 3.12. A axial sealing ring 3.13 prevents air leakage, and a second insulating sleeve 3.14 provides insulation to prevent electrical leakage. An external negative electrode plate 3.24 is fixedly installed on the second insulating sleeve 3.14 using three clamping round nuts 3.15. A tightening nut 3.16 and an insulating component 3.17 connect the external water inlet pipe 3.23 to the through groove of the copper pipe 3.9, facilitating replacement or maintenance of the external water inlet pipe 3.23. The insulating component 3.17 prevents motor leakage. An external positive electrode plate 3.22 is fixed on the sealing component 3.18 via an electrode insulating sleeve 3.19. A sealing nut 3.20 connects the external water outlet pipe 3.21 to the copper pipe of the flowing water outlet pipe 3.3 on the electrode insulating sleeve 3.19.

[0085] The piping assembly includes a heating inlet pipe 2.11, an inlet pipe sealing sleeve 2.12, a heating outlet pipe 2.13, and an outlet pipe sealing sleeve 2.14. One end of the heating inlet pipe 2.11 and the heating outlet pipe 2.13 are connected to the inlet pipe sealing sleeve 2.12 and the outlet pipe sealing sleeve 2.14, and the flow inlet pipe 3.1 and the flow outlet pipe 3.3, respectively. The other end of the heating inlet pipe 2.11 and the heating outlet pipe 2.13 are connected to the inner cavity environment where the upper induction coil 2.1 and the lower induction coil 2.5 are located in the induction heating system 2, respectively. The inner cavity environments where the upper induction coil 2.1 and the lower induction coil 2.5 are located are interconnected.

[0086] Specifically, the other end of the heating water inlet pipe 2.11 is connected via the water inlet pipe sealing sleeve 2.12, the first connecting nut 3.2 and the flow water inlet pipe 3.1, respectively, and the other end of the heating water outlet pipe 2.13 is connected via the water outlet pipe sealing sleeve 2.14, the second connecting nut 3.4 and the flow water outlet pipe 3.3, respectively.

[0087] External outlet pipe 3.21 and external inlet pipe 3.23 are connected to the inlet and outlet of the circulating water machine, respectively. In practice, external outlet pipe 3.21 is connected to the inlet pipe of the circulating water machine, and external inlet pipe 3.23 is connected to the outlet pipe of the circulating water machine, forming a closed circulating water cooling system to cool the induction heating system 2.

[0088] Positive electrode 3.5 and negative electrode 3.8 are electrically connected to the upper induction coil 2.1 and the lower induction coil 2.5, respectively. External positive electrode plate 3.22 and external negative electrode plate 3.24 are connected to the positive and negative terminals of an external power supply, respectively. In a specific implementation, external positive electrode plate 3.22 is connected to the positive terminal of the high-frequency AC power supply cabinet 4.7, which serves as the AC power supply, and external negative electrode plate 3.24 is connected to the negative terminal of the high-frequency AC power supply cabinet 4.7, forming a closed-loop circuit to provide power to the induction heating system 2.

[0089] The inner cavity containing the upper induction coil 2.1 is connected to the heating water inlet pipe 2.11, which is connected to the circulating water inlet pipe 3.1 of the circulating water cooling system 3 via the water inlet pipe sealing sleeve 2.12. The inner cavity containing the lower induction coil 2.5 is connected to the heating water outlet pipe 2.13, which is connected to the circulating water outlet pipe 3.3 of the circulating water cooling system 3 via the water outlet pipe sealing sleeve 2.14. The cooling water provided by the circulating water cooling system 3 cools the copper pipe.

[0090] like Figure 5 As shown, the function of the temperature control system 4 is to ensure that the test sample 1.1 is heated to a predetermined temperature and maintained at that temperature until the end of the experiment by controlling the heating power of the induction power supply. The system includes thermocouples 4.1, thermocouple extension lines 4.2, high-speed slip rings 4.3, data acquisition modules 4.4, data conversion and transmission modules 4.6, and a high-frequency AC power supply cabinet 4.7. Thermocouples 4.1 are fixedly mounted on the surface of the test sample 1.1 corresponding to the upper induction coil 2.1 and lower induction coil 2.5 of the induction heating system 2. Thermocouples 4.1 are connected via thermocouple extension lines 4.2, high-speed slip rings 4.3, and data acquisition modules 4.4. Thermocouple extension lines 4.2 pass through the sample chuck 1 and the centrifuge spindle before being electrically connected to the high-speed slip ring 4.3, which is positioned on the centrifuge spindle. The data acquisition module 4.4 is communicatively connected to the high-frequency AC power supply cabinet 4.7 via the data conversion and transmission modules 4.6. The high-frequency AC power supply cabinet 4.7 is electrically connected to the circulating water machine, the external positive electrode plate 3.22, and the external negative electrode plate 3.24 of the circulating water cooling system 3.

[0091] In the specific implementation, control software 4.5 is also set up, which is connected to data acquisition module 4.4 and data conversion and transmission module 4.6 respectively.

[0092] During the experiment, thermocouple 4.1 was welded to the center of the upper induction coil 2.1 and the lower induction coil 2.5 corresponding to the test sample 1.1. Then, thermocouple 4.1 was connected to the high-speed slip ring 4.3 through the hollow spindle of the centrifuge via thermocouple extension wire 4.2. It was then connected to the data acquisition module 4.4, control software 4.5, and data conversion and transmission module 4.6 via wires. Finally, the control signal line was connected to the high-frequency AC power supply cabinet 4.7 to form a temperature control system.

[0093] The present invention also designs different specimens to better test the mechanical properties of the metal materials in the specimens.

[0094] The structure of the first test specimen 1.1 is shown below. Figure 2 , for grooved specimens and related similar structures;

[0095] The structure of the second type of test specimen 1.1 is shown below. Figure 6, for flat plate specimens and related similar structures;

[0096] The structure of the third type of test specimen 1.1 is shown below. Figure 7 , for round bar specimens and related similar structures;

[0097] The structure of the fourth test specimen 1.1 is shown below. Figure 8 , structural gradient specimens and related similar structures.

[0098] The temperature calibration device also provides various in-situ heating modes for high-speed environments, offering new experimental conditions for material performance testing under different temperatures and speeds. The heating modes of this invention include, but are not limited to, the following:

[0099] Heating Mode 1: A uniform temperature heating mode is applied to the standard section 1.1.2 of the test sample 1.1 at high speed. Figure 10 .

[0100] The experimental materials are of the same type. During the experiment, the distance h between the standard segment 1.1.2 and the upper induction coil 2.1 and the lower induction coil 2.5 remains the same, and the heating power and heating frequency remain unchanged within time t. A constant and uniform temperature field is applied to the standard segment 1.1.2.

[0101] Heating Mode Two: A periodic alternating temperature heating mode is applied to the standard section 1.1.2 of the test sample 1.1 at high speed. Figure 11 .

[0102] The experimental materials are of the same type. During the experiment, the distance h between the standard segment 1.1.2 and the upper induction coil 2.1 and the lower induction coil 2.5 remains the same. The heating frequency remains unchanged, but the heating power is periodically changed within time t. An alternating temperature field of T1 is applied to the standard segment 1.1.2 within time t1 and T2 within time t2.

[0103] Heating Mode 3: A temperature gradient heating mode that applies constant temperature to the standard section 1.1.2 of the test sample 1.1 at high speed. Figure 12 .

[0104] Using the same type of experimental materials, the standard segment 1.1.2 of test specimen 1.1 was machined into an arc with radius R. During the experiment, the distance h between the lowest point of the arc of standard segment 1.1.2 and the upper induction coil 2.1 and the lower induction coil 2.5 remained constant, and the heating power and heating frequency remained constant within time t. Since the distance from the arc-shaped standard segment 1.1.2 to the induction coils 2.1 and 2.5 changes continuously, according to the principle of induction heating, under the same power and frequency conditions, the sample heating temperature is inversely proportional to its distance from the induction coil. Therefore, a constant temperature gradient was applied to the standard segment 1.1.2 of test specimen 1.1.

[0105] The specific implementation process of this invention is as follows:

[0106] The experimental temperature and centrifuge speed were determined based on the experimental conditions.

[0107] The following is based on Figure 10 For example, this illustrates the high-throughput testing of material mechanical properties under high rotational speed and high temperature conditions:

[0108] Step 1: Determine the spindle speed and impeller radius of the centrifuge based on the experimental conditions;

[0109] Step 2: Determine the dimensions and weight of the mass block 1.1.1 in test specimen 1.1, and the dimensions and geometric center of the gauge length segment 1.1.2;

[0110] Step 3: Determine the test temperature and the centrifugal stress applied to the geometric center of gauge length 1.1.2, and then determine the rotational speed corresponding to the centrifugal stress at the geometric center of gauge length 1.1.2 through finite element calculation, and determine the distance between the geometric center of gauge length 1.1.2 and the center of the centrifuge spindle;

[0111] Step 4: Install a temperature calibration sample 5 in one slot 1.2 of the sample chuck 1 according to the distance in Step 3, and install test samples 1.1 in the remaining slots 1.2. Install the temperature calibration sample 5 next to the test sample 1.1. Insert thermocouples into each thermocouple hole of the temperature calibration sample 5, and weld and fix the respective temperature control thermocouples 4.1 at the geometric center of the gauge length section 1.1.2 of the test sample 1.1 and the temperature calibration sample 5. The temperature control thermocouples 4.1 are connected to the temperature control system 4 via temperature extension wires 4.2.

[0112] Since temperature calibration sample 5 and test sample 1.1 are in the same environment, it is assumed that the temperature distribution obtained by temperature calibration sample 5 is the same as that of test sample 1.1.

[0113] Step 5: Without starting the centrifuge, keep the sample chuck 1 and the test sample 1.1 and the calibration sample 5 on it stationary, evacuate the environment inside the centrifuge, and then start the induction heating system 2, the circulating water cooling system 3 and the temperature control system 4. The temperature control system 4 controls the operation of the induction heating system 2 and the circulating water cooling system 3 to apply a temperature load to the test sample 1.1 and the calibration sample 5. After the temperature reaches the predetermined temperature, keep it at that temperature for a period of 30 minutes.

[0114] Temperature data on temperature changes over time were obtained by measuring the temperature control thermocouple 4.1 of test sample 1.1 and temperature calibration sample 5, as well as the thermocouples in each thermocouple hole of temperature calibration sample 5. The data were then analyzed to obtain parameters such as the current, current alternation frequency and power of the upper induction coil 2.1 and the lower induction coil 2.5, and the distance between the upper induction coil 2.1 and the lower induction coil 2.5 during the formal test measurement.

[0115] Step 6: Remove the temperature calibration sample 5 from the slot 1.2 of the sample chuck 1 and replace it with the test sample 1.1, so that the test sample 1.1 is installed in each slot 1.2 of the sample chuck 1. Then start the centrifuge and make the main shaft of the centrifuge rotate at the speed corresponding to the centrifugal stress to carry out the formal test. Control the distance between the upper induction coil 2.1 and the lower induction coil 2.5, the current, the alternating frequency of the current and the power according to the parameters obtained in Step 5, and keep the parameters unchanged until the test sample 1.1 is pulled off and breaks.

[0116] From the moment the centrifuge spindle begins to rotate until the test specimen 1.1 breaks, data on temperature and stress changes are collected in real time using temperature-controlled thermocouples 4.1 and strain gauges, and the specimen is measured as test data.

[0117] This method uses a temperature calibration device to detect the temperature at each point, and also uses the temperature calibration process to set parameters and adjust the conditions applied in subsequent tests, so that the temperature gradient of the specimen during the test is smaller.

Claims

1. A method for calibrating and testing in-situ heating of a centrifuge under high speed and high temperature, characterized in that: Step 1: Determine the spindle speed and impeller radius of the centrifuge based on the experimental conditions; Step 2: Determine the dimensions and weight of the mass block (1.1.1) in the test specimen (1.1), and the dimensions and geometric center of the gauge length segment (1.1.2); Step 3: Determine the test temperature and the centrifugal stress applied to the geometric center of the gauge length section (1.1.2), and then determine the rotational speed corresponding to the centrifugal stress at the geometric center of the gauge length section (1.1.2), and determine the distance between the geometric center of the gauge length section (1.1.2) and the center of the centrifuge spindle; Step 4: Install a temperature calibration sample (5) in one slot (1.2) of the sample chuck (1) and install test samples (1.1) in the remaining slots (1.2). Install the temperature calibration sample (5) next to the test sample (1.1). Insert thermocouples into each thermocouple hole of the temperature calibration sample (5), and fix the upper temperature control thermocouple (4.1) at the geometric center of the gauge length (1.1.2) of both the test sample (1.1) and the temperature calibration sample (5). Step 5: Without starting the centrifuge, the sample chuck (1) and the test sample (1.1) and the temperature calibration sample (5) on it are kept still. The environment is evacuated. Then, the induction heating system (2), the circulating water cooling system (3) and the temperature control system (4) are started. The temperature control system (4) controls the operation of the induction heating system (2) and the circulating water cooling system (3) to apply a temperature load to the test sample (1.1) and the temperature calibration sample (5). After the temperature reaches the predetermined temperature, it is kept at that temperature for a period of time. The temperature data obtained by measuring the temperature of the temperature control thermocouple (4.1) of the test sample (1.1) and the temperature calibration sample (5) and the thermocouples in each thermocouple hole of the temperature calibration sample (5) are analyzed and processed to obtain the parameters of the current, current alternation frequency and distance between the upper induction coil (2.1) and the lower induction coil (2.5) during the formal test measurement. Step 6: Remove the temperature calibration sample (5) from the slot (1.2) of the sample chuck (1), replace it with the test sample (1.1), and start the centrifuge again. Rotate the main shaft of the centrifuge to the speed corresponding to the centrifugal stress for formal test. Control the distance between the upper induction coil (2.1) and the lower induction coil (2.5) and the current and current alternation frequency according to the parameters obtained in Step 5. Keep the parameters unchanged until the test sample (1.1) is pulled off and breaks. The method employs a temperature calibration test device, which includes a sample chuck (1), an induction heating system (2), a circulating water cooling system (3), and a temperature control system (4). The sample chuck (1) is coaxially mounted on the main shaft of the centrifuge and rotates synchronously with the main shaft of the centrifuge. The test sample (1.1) and the temperature calibration sample (5) are mounted on the sample chuck (1). The induction heating system (2) is coaxially mounted on the centrifuge and does not rotate with the main shaft of the centrifuge. The induction heating system (2) is connected to the circulating water cooling system (3). The temperature control system (4) is connected to the circulating water cooling system (3) and the test sample (1.1) respectively. The circulating water cooling system (3) includes a pipe assembly installed in the induction heating system (2), a flow inlet pipe (3.1), a flow outlet pipe (3.3), a positive electrode (3.5), an inner insulating sleeve (3.6), a metal sleeve (3.7), a negative electrode (3.8), a copper pipe (3.9), a first insulating sleeve (3.10), a fixed flange (3.11), a second insulating sleeve (3.14), a clamping round nut (3.15), a seal (3.18), an electrode insulating sleeve (3.19), an external outlet pipe (3.21), an external positive electrode plate (3.22), an external inlet pipe (3.23), and an external negative electrode plate (3.24); the copper pipe (3.5) is also included. .9) An outer insulating sleeve (3.10) is fitted with a first insulating sleeve (3.10) for insulation against the metal sleeve (3.7). The metal sleeve (3.7) is sealed in the center hole of a fixed flange (3.11) by a second insulating sleeve (3.14) and a shaft sealing ring (3.13). The fixed flange (3.11) is fixed to the experimental chamber cover of the centrifuge. The two ends of the copper tube (3.9), the first insulating sleeve (3.10), and the metal sleeve (3.7) are fixed and sealed by an inner insulating sleeve (3.6) and a sealing element (3.18), respectively. One end of the copper tube (3.9) passes through the inner insulating sleeve (3.6) and flows out. The water pipe (3.3) is coaxially connected, and a positive electrode (3.5) is set at the end of the copper pipe (3.9) after passing through the inner insulating sleeve (3.6); the external positive electrode plate (3.22) is electrically connected to the copper pipe (3.9) through the electrode insulating sleeve (3.19), so that the positive electrode (3.5) is directly connected to the external positive electrode plate (3.22) through the copper pipe (3.9); the other end of the copper pipe (3.9) is connected to the external water outlet pipe (3.21), so that the water outlet pipe (3.3) flows directly through the copper pipe (3.9) and the external water outlet pipe (3.21); there is an annular pipe gap between the first insulating sleeve (3.10) and the metal sleeve (3.7) to serve as an inlet channel. One end of the water channel is connected to a metal pipe and a flow inlet pipe (3.1). A negative electrode (3.8) is set near the end of the flow inlet pipe (3.1). An external negative electrode plate (3.24) is electrically connected to a metal sleeve (3.7) through a tightening round nut (3.15), so that the negative electrode (3.8) is electrically connected to the external negative electrode plate (3.24) after passing through the metal pipe and the metal sleeve (3.7) in sequence. A through groove is opened on the pipe wall at one end of the metal sleeve (3.18), and the through groove is connected to the external inlet pipe (3.23) in flow, so that the flow inlet pipe (3.1) is connected to the external inlet pipe (3.23) after passing through the metal pipe, the water inlet channel, and the through groove in sequence. The pipeline assembly includes a heating inlet pipe (2.11), an inlet pipe sealing sleeve (2.12), a heating outlet pipe (2.13), and an outlet pipe sealing sleeve (2.14). One end of the heating inlet pipe (2.11) and the heating outlet pipe (2.13) are connected to the inlet pipe sealing sleeve (2.12), the outlet pipe sealing sleeve (2.14), the flow inlet pipe (3.1), and the flow outlet pipe (3.3), respectively. The other end of the heating inlet pipe (2.11) and the heating outlet pipe (2.13) are connected to the inner cavity environment where the upper induction coil (2.1) and the lower induction coil (2.5) are located in the induction heating system (2). The inner cavity environments where the upper induction coil (2.1) and the lower induction coil (2.5) are located are interconnected.

2. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 1, characterized in that: The sample chuck (1) includes a chuck body, a chuck groove (1.2) and a flange (1.3). The flange (1.3) is coaxially installed at both ends of the center of the chuck body. The chuck body is coaxially fixedly connected to the main shaft of the centrifuge through the flange (1.3). Multiple chuck grooves (1.2) are opened around the circumference of the chuck body. The multiple chuck grooves (1.2) are arranged at intervals along the circumference. Each chuck groove (1.2) is used to install a test sample (1.1).

3. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 1, characterized in that: The test specimen (1.1) is strip-shaped and includes a mass block (1.1.1), a standard section (1.1.2), a load-bearing section (1.1.3), and an assembly tenon (1.1.4) connected in sequence. The mass block (1.1.1), the standard section (1.1.2), the load-bearing section (1.1.3), and the assembly tenon (1.1.4) are all arranged in sequence along the strip shape of the test specimen (1.1). The assembly tenon (1.1.4) is fitted into the slot (1.2) of the sample chuck (1).

4. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 2, characterized in that: The temperature calibration sample (5) and the test sample (1.1) have the same structure, shape and size. The difference is that the temperature calibration sample (5) has multiple thermocouple holes of different depths inside. Each thermocouple hole is arranged radially along the sample chuck (1) and each thermocouple hole is equipped with a thermocouple.

5. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 1, characterized in that: The induction heating system (2) includes an upper induction coil (2.1), an upper fixing plate (2.3), a lower induction coil (2.5), and a lower fixing plate (2.7). The upper fixing plate (2.3) and the lower fixing plate (2.7) are fixedly arranged parallel to each other at intervals. A sample chuck (1) is arranged in the interval between the upper fixing plate (2.3) and the lower fixing plate (2.7). The annular upper induction coil (2.1) and the lower induction coil (2.5) are fixed to the bottom surface of the upper fixing plate (2.3) and the top surface of the lower fixing plate (2.7) through the upper induction coil insulation layer (2.2) and the lower induction coil insulation layer (2.6), respectively.

6. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 5, characterized in that: The upper induction coil (2.1) and the lower induction coil (2.5) are respectively wrapped in the inner cavity of the upper induction coil insulation layer (2.2) and the lower induction coil insulation layer (2.6). The inner cavities of the upper induction coil insulation layer (2.2) and the lower induction coil insulation layer (2.6) are connected by a pipe. The upper induction coil insulation layer (2.2) and the lower induction coil insulation layer (2.6) are respectively fixed to the bottom surface of the upper fixing plate (2.3) and the bottom fixing plate (2.7) and the top surface by the upper fixing screw (2.4) and the lower fixing screw (2.8).

7. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 6, characterized in that: The positive electrode (3.5) and negative electrode (3.8) are electrically connected to the upper induction coil (2.1) and the lower induction coil (2.5) respectively, and the external positive electrode plate (3.22) and the external negative electrode plate (3.24) are connected to the positive and negative terminals of the external power supply respectively.

8. The temperature calibration test method for in-situ heating of a centrifuge under high speed and high temperature as described in claim 1, characterized in that: The temperature control system (4) includes a thermocouple (4.1), a thermocouple extension line (4.2), a high-speed slip ring (4.3), a data acquisition module (4.4), a data conversion and transmission module (4.6), and a high-frequency AC power supply cabinet (4.7). Thermocouples (4.1) are fixed on the test sample (1.1) corresponding to the upper induction coil (2.1) and the lower induction coil (2.5) of the induction heating system (2). Thermocouples (4.1) are connected via thermocouple extension line (4.2), high-speed slip ring (4.3), and data acquisition module (4.4). Data acquisition module (4.4) is connected to high-frequency AC power supply cabinet (4.7) via data conversion and transmission module (4.6). High-frequency AC power supply cabinet (4.7) is electrically connected to external positive electrode plate (3.22) and external negative electrode plate (3.24) of circulating water cooling system (3).

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