Temperature calibration device for in-situ heating of centrifuge under high speed and high temperature

Abstract

The present invention discloses a temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature. The device 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 the centrifuge and rotates synchronously with the main shaft of the centrifuge, a test specimen and a temperature calibration specimen are mounted on the sample chuck, the induction heating system is coaxially mounted on the centrifuge and does not rotate with the main shaft of the centrifuge, the induction heating system is connected to the circulating water cooling system, and the temperature control system is respectively connected to the circulating water cooling system and the test specimen. The present invention solves the problem that the induction heating temperature can only be set at high speed and the temperature cannot be accurately calibrated. The local heating temperature of the test component can be set at high speed and then the temperature can be accurately calibrated to provide the temperature distribution of the test component along the direction of centrifugal force; and it can be adjusted as needed to meet the temperature calibration needs of different structural components.

Description

Technical Field

[0001] The invention relates to a centrifuge heating temperature calibration device in the field of in-situ heating of metal materials, and in particular to a centrifuge in-situ heating temperature calibration device for metal materials under high speed and high temperature. Background Art

[0002] The national standards GB / T 38822-2020 "Metallic materials creep-fatigue test methods" and GB / T6825.1-2008 "Testing of static uniaxial testing machines Part 1: Test and calibration of force measuring systems of tension and (or) compression testing machines" both specify the test methods for the mechanical properties of metallic materials, but the test environment specified in these standards is 1G (G=9.8m / s 2 ), which can satisfy the research on the mechanical properties of metal materials themselves. However, in turbine propulsion systems, such as aircraft engines, aerospace engines, industrial and ship gas turbines, automotive and train turbochargers, and other power system key components such as compressor blades, fan blades, and turbine blades are in a high-speed rotation state during normal operation, that is, the service environment is usually a centrifugal high-gravity environment.

[0003] A turbine propulsion system is typically a turbine power unit that converts the heat energy from fuel combustion into mechanical energy through the guide vanes, where the thermal expansion of the blades creates work, driving the turbine. A turbocharger, on the other hand, utilizes the thermal expansion of diesel (or gasoline) engine exhaust gases on the turbine to convert waste heat into mechanical energy. During operation, the turbine blades of these power units rotate at high speeds around the engine axis, generating work by the expansion of the combustion gases, converting their potential and thermal energy into mechanical work for the rotor. Therefore, the loads on the turbine blades during operation include aerodynamic forces, centrifugal forces, and thermal loads. The centrifugal force generated by high-speed rotation is a body force, primarily producing radial tensile stresses in the blades. For torsionally configured blades, this also creates torsional stresses. If the stacking line of the blades does not completely coincide with the radial line, centrifugal forces can also cause bending stresses in the blades. The thermal stresses generated by thermal loads are closely related to the blade's temperature gradient and geometric constraints. A greater temperature gradient increases the thermal stresses. However, the key material mechanical property data currently used to design turbine blades for turbine propulsion systems comes from static, uniaxial stress state data obtained by testing standard specimens under 1G conditions, such as endurance, creep, and fatigue. While standard specimen mechanical property data can provide a design basis for turbine blade strength design, due to the complex geometry of the blades and their complex stress state, which differs from that of the standard specimens, the material mechanical property data obtained from standard specimens does not consider the impact of high speed, blade geometry, and other factors on their structural reliability, and cannot be directly used to evaluate turbine blade life. Summary of the Invention

[0004] In view of the shortcomings of the current static mechanical properties testing of metal materials under 1G and the lack of in-situ heating and temperature calibration devices suitable for the mechanical properties testing of metal materials under high speed and high temperature, the present invention provides an in-situ heating and temperature calibration device that can apply in-situ heating to metal materials under high-speed rotation environment, solving the key problems of in-situ heating, temperature calibration and intelligent temperature control in the mechanical properties testing of metal materials under high speed and high temperature.

[0005] The in-situ heating of metal materials under high-speed rotation environment described in the present invention means that during the mechanical property test of metal materials or components, the high-speed rotating test materials or components are always in an in-situ heating state until the test is completed.

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

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

[0008] The high speed mentioned in the present invention means that the maximum speed of the centrifuge during the experiment is not less than 5000 rpm.

[0009] The technical solution adopted in the present invention is:

[0010] The device includes a sample chuck, an induction heating system, a circulating water cooling system and a temperature control system; the sample chuck is coaxially installed on the main shaft of the centrifuge and rotates synchronously with the main shaft of the centrifuge, the test sample and the temperature calibration sample are installed on the sample chuck, the induction heating system is coaxially installed on the centrifuge and does not rotate with the main shaft of the centrifuge, the induction heating system is connected to the circulating water cooling system, and the temperature control system is respectively connected to the circulating water cooling system and the test sample.

[0011] The sample chuck includes a disc body, a slot and a flange. Flanges are coaxially installed at both ends of the center of the disc body. The disc body is coaxially fixedly connected to the main shaft of the centrifuge through the flange. Multiple slots are opened around the disc body along the circumference. The multiple slots are arranged at intervals along the circumference, and each slot is used to install a test sample.

[0012] The test specimen is in the shape of a strip, and includes a mass block, a rectangular section, a load-bearing section and an assembly tenon connected in sequence. The mass block, the rectangular section, the load-bearing section and the assembly tenon are arranged in sequence along the strip of the test specimen, and the assembly tenon is embedded in the slot of the sample chuck.

[0013] The temperature calibration sample and the test sample have the same structure, shape and size. The difference is that a plurality of thermocouple holes of different depths are opened inside the temperature calibration sample. Each thermocouple hole is arranged along the radial direction of the sample chuck, and each thermocouple hole is installed with a thermocouple.

[0014] The induction heating system includes an upper induction coil, an upper fixed plate, a lower induction coil and a lower fixed plate; the upper fixed plate and the lower fixed plate are fixedly arranged in parallel with an upper and lower interval, and a sample chuck is arranged in the interval between the upper and lower fixed plates; the annular upper induction coil and the lower induction coil are fixed to the bottom surface of the upper fixed plate and the top surface of the lower fixed plate respectively through the upper induction coil insulation layer and the lower induction coil insulation layer.

[0015] The upper induction coil and the lower induction coil are respectively wrapped in the inner cavities 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 pipeline. The upper induction coil insulation layer and the lower induction coil insulation layer are respectively fixed to the bottom surface of the upper fixed plate and the top surface of the lower fixed plate by an upper fixing screw and a lower fixing screw.

[0016] The circulating water cooling system includes a pipeline assembly arranged in the induction heating system, as well as a circulating water inlet pipe, a circulating water outlet pipe, a positive electrode, an inner insulating sleeve, a metal sleeve, a negative electrode, a copper tube, an insulating sleeve, a fixed flange, an insulating sleeve, a tightening round nut, a seal, an electrode insulating sleeve, an external water outlet pipe, an external positive electrode plate, an external water inlet pipe and an external negative electrode plate; the outer sleeve of the copper tube is provided with an insulating sleeve for insulating from the metal sleeve, and the outer sleeve of the insulating sleeve is provided with a metal sleeve; the middle part of the metal sleeve is sealed in the center hole of the fixed flange through the insulating sleeve and the shaft sealing ring, the fixed flange is fixed on the experimental chamber cover of the centrifuge, and the two ends of the copper tube, the insulating sleeve and the metal sleeve are respectively fixed and sealed by the inner insulating sleeve and the seal; one end of the copper tube passes through the inner insulating sleeve and is coaxially connected to the circulating water outlet pipe, and passes through the inner insulating sleeve at one end of the copper tube A positive electrode is set at the end of the back; the external positive electrode plate is electrically connected to the copper tube through the electrode insulating sleeve, so that the positive electrode is directly electrically 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 circulating water outlet pipe directly passes through the copper tube and the external water outlet pipe; there is an annular pipe gap between the insulating sleeve and the metal sleeve for use as a water inlet channel, one end of the water inlet channel is connected to the circulating water inlet pipe through the metal pipe, and a negative electrode is set near the end of the circulating 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 electrically connected to the external negative electrode plate after passing through the metal pipe, the metal sleeve in turn; a through groove is opened on the pipe wall of the metal sleeve at one end of the connecting seal, and the through groove is connected to the external water inlet pipe, so that the circulating water inlet pipe passes through the metal pipe, the water inlet channel, the through groove and the external water inlet pipe in turn.

[0017] The pipeline assembly includes a heating water inlet pipe, a water inlet pipe sealing sleeve, a heating water outlet pipe and a water outlet pipe sealing sleeve; one end of the heating water inlet pipe and the heating water outlet pipe are respectively connected to the circulating water inlet pipe and the circulating water outlet pipe through the water inlet pipe sealing sleeve and the water outlet pipe sealing sleeve, and the other end of the heating water 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, and the inner cavity environment where the upper induction coil and the lower induction coil are located is connected to each other.

[0018] The external water outlet pipe and the external water inlet pipe are respectively connected to the water inlet and the water outlet of the circulating water machine; the positive electrode and the negative electrode are respectively electrically connected to the upper induction coil and the lower induction coil, and the external positive electrode plate and the external negative electrode plate are respectively connected to the positive and negative poles of the external power supply.

[0019] The temperature control system includes a thermocouple, a thermocouple extension line, a high-speed slip ring, a data acquisition module, a data conversion and transmission module, and a high-frequency AC power supply cabinet; thermocouples are fixedly provided on the surface of the test sample corresponding to the upper induction coil and the lower induction coil of the induction heating system, the thermocouples are connected to the data acquisition module via the thermocouple extension line and the high-speed slip ring, the data acquisition module is communicatively connected to the high-frequency AC power supply cabinet via the data conversion and transmission module, and the high-frequency AC power supply cabinet is electrically connected to the external positive electrode plate and the external negative electrode plate of the circulating water cooling system.

[0020] Since the heating system uses induction heating outside the specimen, the temperature of the outer surface of the specimen will be higher than the internal temperature, resulting in a yield effect. The temperature inside the specimen is low and the temperature outside is high. In this way, the temperature of each part of the specimen is not uniform, which greatly reduces the effectiveness of the specimen test and experiment, and increases the test error.

[0021] In order to avoid such problems, the present invention has designed a temperature calibration device, which can ensure that the temperature of the test sample in the formal test is evenly distributed when heated, and the temperature at all locations reaches the preset temperature with an error of no more than five degrees Celsius.

[0022] The temperature calibration device of the present invention can ensure that the temperature of the test piece along the direction perpendicular to the centrifugal force is uniform and has no gradient, while the temperature along the direction of the centrifugal force can be non-uniform and has a gradient.

[0023] The beneficial effects of the present invention are:

[0024] (1) The problem that the induction heating temperature can only be set at high speed and the temperature cannot be accurately calibrated is solved. The present invention can set the local heating temperature of the test component at high speed, then accurately calibrate the temperature, and provide the temperature distribution of the test component along the direction of centrifugal force;

[0025] (2) The shape of the calibration specimen and the spacing and depth of the installed temperature-calibration thermocouples can be adjusted as needed to meet the temperature calibration requirements of different structural components. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 1 is a schematic structural diagram of a sample chuck 1;

[0027] Figure 2 is a schematic diagram of the structure of test specimen 1.1;

[0028] Figure 3 is a schematic structural diagram of the induction heating system 2;

[0029] Figure 4 It is a structural diagram of the circulating water cooling system 3;

[0030] Figure 5 is a schematic diagram of the temperature control system 4;

[0031] Figure 6 is a schematic diagram of the structure of a test sample 1.1;

[0032] Figure 7 is a schematic diagram of the structure of a test sample 1.1;

[0033] Figure 8 is a schematic diagram of the structure of a test sample 1.1;

[0034] Figure 9 Schematic diagram of the installation of the sample chuck 1 and the induction heating system 2 on the centrifuge;

[0035] Figure 10 1 is a schematic structural diagram of the temperature calibration sample 5;

[0036] Figure 11 This is a layout diagram after the test specimen 1.1, the temperature calibration specimen 5, the sample chuck 1 and the induction heating system 2 are installed together.

[0037] In the picture:

[0038] Sample chuck 1: test specimen 1.1, chuck slot 1.2, flange 1.3;

[0039] Mass block 1.1.1, standard section 1.1.2, load-bearing section 1.1.3, assembly tenon 1.1.4;

[0040] Induction heating system 2: upper induction coil 2.1, upper induction coil insulation layer 2.2, upper fixing plate 2.3, upper fixing screw 2.4, lower induction coil 2.5, lower induction coil insulation layer 2.6, lower fixing plate 2.7, lower fixing screw 2.8, connecting rod 2.9, nut 2.10, heating water inlet pipe 2.11, water inlet pipe sealing sleeve 2.12, heating water outlet pipe 2.13, water outlet pipe sealing sleeve 2.14;

[0041] Circulating water cooling system 3: water inlet pipe 3.1, connecting nut 3.2, water outlet pipe 3.3, connecting nut 3.4, positive electrode 3.5, inner insulating sleeve 3.6, negative electrode 3.8, copper tube 3.9, insulating gland 3.10, fixing flange 3.11, fixing screw 3.12, shaft sealing ring 3.13, insulating gland 3.14, tightening round nut 3.15, tightening nut 3.16, insulating element 3.17, sealing element 3.18, electrode insulating gland 3.19, sealing nut 3.20, external water outlet pipe 3.21, external positive electrode plate 3.22, external water inlet pipe 3.23, and external negative electrode plate 3.24;

[0042] Temperature control system 4: thermocouple 4.1, thermocouple extension wire 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;

[0043] 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 DESCRIPTION

[0044] The present invention will be further described below with reference to the accompanying drawings and specific implementations.

[0045] like Figure 9 As shown, 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, a test specimen 1.1 and a temperature calibration specimen 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 but remains fixed, the induction heating system 2 is connected to the circulating water cooling system 3, and the temperature control system 4 is respectively connected to the circulating water cooling system 3 and the test specimen 1.1.

[0046] The centrifuge is an ultra-gravity centrifuge.

[0047] like Figure 1 As shown, the sample chuck 1 is used to mount a test specimen and is connected to the centrifuge via a spindle. It comprises a disc body, a slot 1.2, and a flange 1.3. Flanges 1.3 are coaxially fixedly mounted at both ends of the center of the disc body. The disc body is coaxially fixedly connected to the spindle of the centrifuge via the flange 1.3. A plurality of slots 1.2 are circumferentially arranged around the disc body. The plurality of slots 1.2 are spaced apart circumferentially, and each slot 1.2 is used to mount a test specimen 1.1.

[0048] The flange 1.3 is used to connect the sample chuck 1 to the centrifuge main shaft. During the experiment, the high-speed rotation of the centrifuge main shaft drives the sample chuck 1 to rotate, thereby applying a centrifugal load to the test sample 1.1.

[0049] The card slot 1.2 is mainly used to fix the test sample 1.1 that rotates at high speed. The assembly tenon 1.1.4 of the test sample 1.1 is installed in the card slot 1.2, so that the sample chuck 1 drives the test sample 1.1 to rotate together when it rotates.

[0050] like Figure 2 As shown, the test specimen 1.1 is made of metal material for testing performance and is in the shape of a strip, including a mass block 1.1.1, a gauge 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 gauge 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 of the test specimen 1.1. Specifically, the mass block 1.1.1, the gauge section 1.1.2, the load-bearing section 1.1.3 and the assembly tenon 1.1.4 are arranged in sequence from the slot 1.2 of the sample chuck 1 radially outward, and the assembly tenon 1.1.4 is embedded in the slot 1.2 of the sample chuck 1.

[0051] In the specific implementation, the width of the assembly tenon 1.1.4 and the width of the slot 1.2 of the sample chuck 1 are both larger than the width of the mass block 1.1.1, the standard section 1.1.2 and the load-bearing section 1.1.3, so that the test sample 1.1 can be stably embedded and positioned when driven by the sample chuck 1 to rotate at high speed.

[0052] The mass block 1.1.1 is used to exert a centrifugal stress on the standard moment section 1.1.3 by the centrifugal force generated by its own weight at high speed. The mass block 1.1.1 has a mass m, an effective radius r, and a speed ω. Then the centrifugal force F generated by the mass block 1.1.1 is F = mrω 2 The weight m of the mass 1.1.1 depends on the fracture strength of the material under the experimental conditions.

[0053] Gauge section 1.1.2 is connected to mass block 1.1.1 and is used to bear the centrifugal and thermal stresses exerted by mass block 1.1.1 under high-speed rotation and high temperature. The shape of gauge section 1.1.2 can be changed according to actual needs.

[0054] The load-bearing section 1.1.3 is used to connect the gauge section 1.1.2 and the assembly tenon 1.1.4.

[0055] According to the experimental requirements, the test specimen 1.1 can be designed as follows Figure 2 、 Figure 6-Figure 8 structure.

[0056] One or both of a thermocouple and a strain gauge are arranged at the center of the gauge section 1.1.2 of the test specimen 1.1.

[0057] like Figure 10As shown, the temperature calibration sample 5 and the test sample 1.1 have the same structure, shape and size. The difference is that a plurality of thermocouple holes of different depths are opened inside the temperature calibration sample 5. Each thermocouple hole is opened and arranged along the radial direction of the disc body of the sample chuck 1, and each thermocouple hole is installed with a thermocouple.

[0058] In a specific implementation, 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 opened on the radial outer end surface of the sample chuck 1. A thermocouple is installed in each thermocouple hole, and the thermocouple is installed in the bottom of the thermocouple hole.

[0059] To calibrate the temperatures of sections A, B, C, D, E, F, and G on temperature calibration specimen 5, thermocouple holes 5-1, 5-2, 5-3, 5-4, 5-5, 5-6, and 5-7 are drilled on specimen 5, corresponding to sections A, B, C, D, E, F, and G, respectively. During calibration, thermocouples are inserted into holes 5-1, 5-2, 5-3, 5-4, 5-5, 5-6, and 5-7, respectively, and then connected to temperature control system 4. The number and depth of the thermocouple holes can be adjusted for specific experiments.

[0060] like Figure 3 As shown, the induction heating system 2 is used to heat a high-speed rotating specimen in situ, applying a temperature load to a designated area of ​​the test specimen 1.1. It comprises 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 and lower fixing plates 2.3 and 2.7 are fixedly arranged parallel to each other with a spacing therebetween. In a specific embodiment, the centrifuge's main shaft rotatably passes through the upper fixing plate 2.3. The sample chuck 1 is positioned in the gap between the upper and lower fixing plates 2.3 and 2.7. The upper and lower fixing plates 2.3 and 2.7 are supported and fixed by a connecting rod 2.9, with a nut 2.10 mounted on the outer end of the connecting rod 2.9. The annular upper and lower induction coils 2.1 and 2.5 are fixed to the bottom and top surfaces of the upper and lower fixing plates 2.3 and 2.7, respectively, via an upper and lower induction coil insulation layer 2.2 and 2.6, respectively.

[0061] The upper fixing plate 2.3 and the lower fixing plate 2.7 are both annular plates, and the upper induction coil 2.1 and the lower induction coil 2.5 are both integrally annular coils.

[0062] Specifically, the upper induction coil 2.1 and the lower induction coil 2.5 are respectively wrapped 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 fixed to the bottom surface of the upper fixing plate 2.3 and the top surface of the lower fixing plate 2.7 by upper fixing screws 2.4 and lower fixing screws 2.8, respectively.

[0063] Among them, the upper induction coil 2.1 is wrapped inside the upper induction coil insulation layer 2.2 to prevent conductivity and serve as insulation; 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 the lower induction coil 2.5 with the insulation layer is also fixed to the lower fixing plate 2.7 by the lower fixing screw 2.8 to form the lower induction coil; then, 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.

[0064] When 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 the conductor with resistance, and heats the metal material through heat conduction. The Joule heat Q generated by the induced current I is equal to I 2 Rt (R is the resistance of the metal material, t is time). During the induction heating process, 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.

[0065] like Figure 4 As shown, the circulating water cooling system 3 is used 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 provided in the induction heating system 2, as well as a circulating water inlet pipe 3.1, a circulating water 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, an insulating gland 3.10, a fixing flange 3.11, an insulating gland 3.14, a compression nut 3.15, a seal 3.18, an electrode insulating gland 3.19, an external outlet pipe 3.21, an external positive electrode plate 3.22, an external water inlet pipe 3.23, and an external negative electrode plate 3.24.

[0066] An insulating sleeve 3.10 and a metal sleeve 3.7 are coaxially mounted on the copper tube 3.9 in sequence radially outward. An insulating sleeve 3.10 is fixedly mounted coaxially on the outside of the copper tube 3.9 for insulation from the metal sleeve 3.7. The metal sleeve 3.7 is coaxially mounted on the outside of the insulating sleeve 3.10, thereby maintaining insulation between the copper tube 3.9 and the metal sleeve 3.7. The middle portion of the metal sleeve 3.7 is sealedly mounted in the center hole of a fixed flange 3.11 via an insulating sleeve 3.14 and a shaft sealing ring 3.13. The fixed flange 3.11 is secured to the experimental chamber cover of the centrifuge via a fixing screw 3.12. The ends of the copper tube 3.9, the insulating sleeve 3.10, and the metal sleeve 3.7 are respectively fixed and sealed by an inner insulating sleeve 3.6 and a sealing member 3.18, which provide insulation and prevent water leakage.

[0067] One end of the copper tube 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 provided at the end of the copper tube 3.9 after passing through the inner insulating sleeve 3.6. The external positive electrode plate 3.22 is electrically connected to the copper tube 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 tube 3.9, with the external positive electrode plate 3.22 being compressed and installed between two adjacent electrode insulating sleeves 3.19. The external positive electrode plate 3.22 passes through the gap between the two adjacent electrode insulating sleeves 3.19 and maintains electrical connection with 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 after passing through the copper tube 3.9.

[0068] The other end of the copper tube 3.9 is connected to the external water outlet pipe 3.21 through the sealing nut 3.20, so that the water outlet pipe 3.3 flows directly through the copper tube 3.9 and the external water outlet pipe 3.21;

[0069] There is an annular pipe gap between the insulating sleeve 3.10 and the metal sleeve 3.7, which serves as a water inlet channel. The water inlet channel is connected to the circulating water inlet pipe 3.1 through a metal pipe at one end near the inner insulating sleeve 3.6. The circulating water inlet pipe 3.1 is provided with a negative electrode 3.8 near the end. The external negative electrode plate 3.24 is electrically connected to the metal sleeve 3.7 through a plurality of 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, wherein the external negative electrode plate 3.24 is clamped and installed between two adjacent clamping round nuts 3.15. The external negative electrode plate 3.24 passes through the gap between the two adjacent clamping round nuts 3.15 and maintains an electrical connection with the external negative electrode plate 3.24. In this way, 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.

[0070] A through slot is formed in the wall of the metal sleeve 3.7 at one end of the tube, which is connected to the sealing member 3.18 and is disposed between the external positive electrode plate 3.22 and the external negative electrode plate 3.24. The through slot is fluidically connected to the external water inlet pipe 3.23. Specifically, an insulating member 3.17 is mounted on the metal sleeve 3.7 around the through slot via a tightening nut 3.16. The external water inlet pipe 3.23 passes through a through hole in the insulating member 3.17 and is connected to the through slot. In this way, the water inlet pipe 3.1 flows through the metal pipe, the water inlet channel, the through slot, and finally to the external water inlet pipe 3.23.

[0071] More specifically, the copper tube 3.9 is a long hollow copper tube, with an insulating sleeve 3.10 installed on the outer periphery for insulation, and a sealing ring installed to prevent air leakage in the experimental cavity.

[0072] The circulating water inlet pipe 3.1 is connected to the heating water inlet pipe 2.11 of the induction heating system 2 via a connecting nut 3.2; the circulating water outlet pipe 3.3 is connected to the heating water outlet pipe 2.13 of the induction heating system 2 via a connecting nut 3.4; the positive electrode 3.5 is installed on the periphery of the circulating water 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 periphery of the circulating water inlet pipe 3.1 to ensure that the cooling water can cool the negative electrode 3.8.

[0073] The metal sleeve 3.7 is mounted on the chamber cover of the experimental chamber via a flange 3.11 using six fixing screws 3.12. A sealing ring 3.13 is then used to prevent air leakage through the shaft, and an insulating sleeve 3.14 is used for insulation to prevent electrical leakage. An external negative electrode plate 3.24 is fixed to the insulating sleeve 3.14 using three tightening round nuts 3.15. An external water inlet pipe 3.23 is connected to the through-slot of the copper tube 3.9 via a tightening nut 3.16 and an insulating member 3.17. The tightening nut 3.16 facilitates replacement or maintenance of the external water inlet pipe 3.23, and the insulating member 3.17 prevents electrical leakage from the motor. An external positive electrode plate 3.22 is secured to the sealing member 3.18 via an electrode insulating sleeve 3.19. An external water outlet pipe 3.21 is connected to the copper tube of the water outlet pipe 3.3 via a sealing nut 3.20 on the electrode insulating sleeve 3.19.

[0074] The pipeline assembly includes a heating water inlet pipe 2.11, a water inlet pipe sealing sleeve 2.12, a heating water outlet pipe 2.13 and a water outlet pipe sealing sleeve 2.14; one end of the heating water inlet pipe 2.11 and the heating water outlet pipe 2.13 are respectively connected to the circulation water inlet pipe 3.1 and the circulation water outlet pipe 3.3 through the water inlet pipe sealing sleeve 2.12 and the water outlet pipe sealing sleeve 2.14, and the other ends of the heating water inlet pipe 2.11 and the heating water outlet pipe 2.13 are respectively connected to the inner cavity environment of the upper induction coil 2.1 and the lower induction coil 2.5 in the induction heating system 2, and the inner cavity environment of the upper induction coil 2.1 and the lower induction coil 2.5 are connected to each other.

[0075] Specifically, the other end of the heating water inlet pipe 2.11 is connected to the circulating water inlet pipe 3.1 via the water inlet pipe sealing sleeve 2.12, the connecting nut 3.2, and the other end of the heating water outlet pipe 2.13 is connected to the circulating water outlet pipe 3.3 via the water outlet pipe sealing sleeve 2.14, the connecting nut 3.4.

[0076] The external water outlet pipe 3.21 and the external water inlet pipe 3.23 are connected to the water inlet and water outlet of the circulating water machine respectively; in specific implementation, the external water outlet pipe 3.21 is connected to the water inlet pipe of the circulating water machine, and the external water inlet pipe 3.23 is connected to the water outlet pipe of the circulating water machine, forming a closed circulating water cooling system to cool the induction heating system 2.

[0077] Positive electrode 3.5 and negative electrode 3.8 are electrically connected to upper induction coil 2.1 and 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 poles of an external power source, respectively. Specifically, external positive electrode plate 3.22 is connected to the positive pole of a high-frequency AC power supply cabinet 4.7, while external negative electrode plate 3.24 is connected to the negative pole of the high-frequency AC power supply cabinet 4.7, forming a closed-loop circuit that provides power to induction heating system 2.

[0078] The inner cavity where the upper induction coil 2.1 is located 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 through the water inlet pipe sealing sleeve 2.12; the inner cavity where the lower induction coil 2.5 is located 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 through the water outlet pipe sealing sleeve 2.14. The copper tube is cooled by the cooling water provided by the cooling system 3.

[0079] like Figure 5 As shown, the temperature control system 4 is used to ensure that the test sample 1.1 is heated to a predetermined temperature and maintained at this temperature until the end of the experiment by controlling the heating power of the induction power supply. The induction heating system 2 includes a thermocouple 4.1, a thermocouple extension cable 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 fixedly mounted on the surface of 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. The thermocouples 4.1 are connected to the data acquisition module 4.4 via the thermocouple extension cable 4.2 and the high-speed slip ring 4.3. The thermocouple extension cable 4.2 passes through the disc body of the sample chuck 1 and the main shaft of the centrifuge and is electrically connected to the high-speed slip ring 4.3. The high-speed slip ring 4.3 is arranged on the main shaft of the centrifuge. 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 module 4.6. The high-frequency AC power supply cabinet 4.7 is electrically connected to the circulating water machine and the external positive electrode plate 3.22 and external negative electrode plate 3.24 of the circulating water cooling system 3.

[0080] In the specific implementation, a control software 4.5 is further provided, and the control software 4.5 is connected to the data acquisition module 4.4 and the data conversion and transmission module 4.6 respectively.

[0081] 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 specimen 1.1. Thermocouple 4.1 was then connected to a high-speed slip ring 4.3 through a thermocouple extension wire 4.2 and the hollow spindle of the centrifuge. Conductive wires then connected the thermocouple 4.1 to a data acquisition module 4.4, control software 4.5, and data conversion and transmission module 4.6. Finally, the control signal line was connected to a high-frequency AC power cabinet 4.7, forming a temperature control system.

[0082] The present invention also designs different specimens to better test the mechanical properties of the metal material of the specimen.

[0083] The structure of the first test specimen 1.1 is shown in Figure 2 , for groove specimens and related similar structures;

[0084] The structure of the second test specimen 1.1 is shown in Figure 6 , for flat specimens and related similar structures;

[0085] The structure of the third test specimen 1.1 is shown in Figure 7 , for round bar specimens and related similar structures;

[0086] The structure of the fourth test specimen 1.1 is shown in Figure 8 , structural gradient specimens and their related similar structures.

[0087] The specific implementation process of the present invention is as follows:

[0088] Step 1: Determine the spindle speed and wheel radius of the centrifuge according to experimental conditions;

[0089] Step 2: Determine the size and weight of mass 1.1.1, and the size and geometric center of gauge section 1.1.2 in test specimen 1.1;

[0090] Step 3: Determine the test temperature and the centrifugal stress applied at the geometric center of the gauge section 1.1.2. Then, determine the speed corresponding to the centrifugal stress at the geometric center of the gauge section 1.1.2 through finite element calculation, and determine the distance from the geometric center of the gauge section 1.1.2 to the center of the centrifuge spindle.

[0091] Step 4: Install a test specimen 1.1 in one of the slots 1.2 of the sample chuck 1 and install test specimens 1.1 in the remaining slots 1.2 according to the distance in step 3, as shown in FIG. Figure 11As shown, a temperature calibration specimen 5 is installed next to the test specimen 1.1; a thermocouple is inserted into each thermocouple hole of the temperature calibration specimen 5, and a temperature control thermocouple 4.1 is welded and fixed to the geometric center of the gauge section 1.1.2 of the test specimen 1.1 and the temperature calibration specimen 5. The temperature control thermocouple 4.1 is connected to the temperature control system 4 via a temperature extension wire 4.2;

[0092] The temperature calibration sample 5 and the test sample 1.1 are in the same environment, and it is believed that the temperature distribution obtained in the calibration sample 5 is the same as the temperature distribution of the test sample 1.1.

[0093] Step 5: Without starting the centrifuge, the sample chuck 1 and the test sample 1.1 and the temperature calibration sample 5 thereon remain stationary. The environment inside the centrifuge 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 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, the temperature is maintained for 30 minutes.

[0094] Temperature data of temperature variation over time are obtained by measuring the temperature-controlling thermocouple 4.1 of the test sample 1.1 and the temperature-calibration sample 5, as well as the thermocouples in the various thermocouple holes of the temperature-calibration sample 5. The data are analyzed and processed to obtain the current, alternating current frequency and power of the upper induction coil 2.1 and the lower induction coil 2.5, and the spacing between the upper induction coil 2.1 and the lower induction coil 2.5 during the formal test measurement.

[0095] 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 rotate the main shaft of the centrifuge to a speed corresponding to the centrifugal stress. According to the parameters obtained in Step 5, control the spacing between the upper induction coil 2.1 and the lower induction coil 2.5, the current, the current alternating frequency, and the power. Keep these parameters unchanged until the test sample 1.1 is broken.

Claims

1. A temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature, characterized by: The device comprises 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, a test sample (1.1) and a 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), and the temperature control system (4) is respectively connected to the circulating water cooling system (3) and the test sample (1.1); The circulating water cooling system (3) includes a pipe assembly arranged in the induction heating system (2) and a circulating water inlet pipe (3.1), a circulating water 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 fixing flange (3.11), a second insulating sleeve (3.14), a tightening round nut (3.15), a sealing member (3.18), an electrode insulating sleeve (3.19), an external water outlet pipe (3.21), an external positive electrode plate (3.22), an external water inlet pipe (3.23) and an external negative electrode plate (3.24); the copper tube (3 .9) is provided with a first insulating sleeve (3.10) for insulation from the metal sleeve (3.7), and the first insulating sleeve (3.10) is provided with a metal sleeve (3.7) on the outside; the middle of the metal sleeve (3.7) is sealed and sleeved 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 on the experimental chamber cover of the centrifuge, and 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 respectively through the inner insulating sleeve (3.6) and the sealing member (3.18); one end of the copper tube (3.9) passes through the inner insulating sleeve (3.6) and flows out The water pipes (3.3) are coaxially butted, and a positive electrode (3.5) is provided 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 electrically connected to the external positive electrode plate (3.22) after passing through the copper pipe (3.9); the other end of the copper pipe (3.9) is butted against the external water outlet pipe (3.21), so that the water outlet pipe (3.3) is directly circulated through the copper pipe (3.9) and the external water outlet pipe (3.21); an annular pipe gap is provided between the first insulating sleeve (3.10) and the metal sleeve (3.7) for serving as a water inlet channel. One end of the water channel is connected to the circulating water inlet pipe (3.1) via a metal pipe, and a negative electrode (3.8) is provided near the end of the circulating water inlet pipe (3.1); the external negative electrode plate (3.24) is electrically connected to the metal sleeve (3.7) via a compression nut (3.15), so that the negative electrode (3.8) is sequentially connected to the external negative electrode plate (3.24) through the metal pipe and the metal sleeve (3.7); the metal sleeve (3.7) is provided with a through groove on the wall of one end of the connecting seal (3.18), and the through groove is connected to the external water inlet pipe (3.23) in a flow manner, so that the circulating water inlet pipe (3.1) is sequentially connected to the metal pipe, the water inlet channel, the through groove, and the external water inlet pipe (3.23); The pipeline assembly comprises a heating water inlet pipe (2.11), a water inlet pipe sealing sleeve (2.12), a heating water outlet pipe (2.13) and a water outlet pipe sealing sleeve (2.14); one end of the heating water inlet pipe (2.11) and the heating water outlet pipe (2.13) are connected to the circulation water inlet pipe (3.1) and the circulation water outlet pipe (3.3) respectively through the water inlet pipe sealing sleeve (2.12) and the water outlet pipe sealing sleeve (2.14); the other ends of the heating water inlet pipe (2.11) and the heating water outlet pipe (2.13) are respectively connected to the inner cavity environment where the upper induction coil (2.1) and the lower induction coil (2.5) in the induction heating system (2) are located, and the inner cavity environments where the upper induction coil (2.1) and the lower induction coil (2.5) are located are connected to each other; The sample chuck (1) comprises a chuck body, a slot (1.2) and a flange (1.3), wherein flanges (1.3) 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 via the flange (1.3), a plurality of slots (1.2) are circumferentially arranged around the chuck body, the plurality of slots (1.2) are circumferentially spaced, and each slot (1.2) is used to mount a test sample (1.1).

2. The temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature according to claim 1, characterized in that: The test specimen (1.1) is in the shape of a strip and comprises a mass block (1.1.1), a rectangular 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 rectangular 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 of the test specimen (1.1), and the assembly tenon (1.1.4) is embedded in the slot (1.2) of the sample chuck (1).

3. The temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature according to claim 1, characterized in that: The temperature calibration sample (5) and the test sample (1.1) have the same structure, shape and size, except that a plurality of thermocouple holes of different depths are provided inside the temperature calibration sample (5), each of the thermocouple holes is provided along the radial direction of the sample chuck (1), and each of the thermocouple holes is equipped with a thermocouple.

4. The temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature according to claim 1, characterized in that: The induction heating system (2) comprises an upper induction coil (2.1), an upper fixed plate (2.3), a lower induction coil (2.5) and a lower fixed plate (2.7); the upper fixed plate (2.3) and the lower fixed plate (2.7) are fixedly arranged in parallel with each other at intervals, and a sample chuck (1) is arranged in the interval between the upper fixed plate (2.3) and the lower fixed 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 fixed plate (2.3) and the top surface of the lower fixed plate (2.7) respectively through the upper induction coil insulation layer (2.2) and the lower induction coil insulation layer (2.6).

5. The temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature according to claim 4, characterized in that: The upper induction coil (2.1) and the lower induction coil (2.5) are respectively wrapped 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 via 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 fixed plate (2.3) and the top surface of the lower fixed plate (2.7) via an upper fixing screw (2.4) and a lower fixing screw (2.8).

6. The temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature according to claim 1, characterized in that: The external water outlet pipe (3.21) and the external water inlet pipe (3.23) are respectively connected to the water inlet and the water outlet of the circulating water machine; the positive electrode (3.5) and the negative electrode (3.8) are respectively electrically connected to the upper induction coil (2.1) and the lower induction coil (2.5); the external positive electrode plate (3.22) and the external negative electrode plate (3.24) are respectively connected to the positive and negative poles of the external power supply.

7. The temperature calibration device for in-situ heating of a centrifuge under high speed and high temperature according to 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 fixedly provided on the surface of 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); the thermocouples (4.1) are connected to the data acquisition module (4.4) via the thermocouple extension line (4.2), the high-speed slip ring (4.3), and the data acquisition module (4.4); 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 module (4.6), and the high-frequency AC power supply cabinet (4.7) is electrically connected to the external positive electrode plate (3.22) and the external negative electrode plate (3.24) of the circulating water cooling system (3).

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