Process method for preparing erosion type tungsten-rhenium thermocouple

Abstract

The invention discloses a process method for preparing an erosion type tungsten-rhenium thermocouple. The method comprises the following steps of: polishing a tungsten sheet and a tungsten-rhenium alloy sheet by using an electric grinder, removing stains on the surfaces of the tungsten sheet and the tungsten-rhenium alloy sheet so that the tungsten sheet and the tungsten-rhenium alloy sheet are smooth, and welding a tungsten wire and the tungsten sheet as well as a tungsten-rhenium alloy wire and the tungsten-rhenium alloy sheet together through electric resistance welding to form positive and negative electrodes of the erosion type tungsten-rhenium thermocouple; sequentially arranging an aluminum oxide sheet, a tungsten sheet, an aluminum oxide sheet, a tungsten-rhenium alloy sheet and an aluminum oxide sheet to form a five-layer sensitive core body structure, applying pressure to the five-layer sensitive core body structure through a clamp, and putting the five-layer sensitive core body structure into a tubular furnace for hot pressed sintering to form a sensitive core body block; smearing high-temperature glue on the aluminum oxide sheets on the two sides of the sensitive core block, stuffing into the stainless steel tube shell, and curing the high-temperature glue by using a hot air gun, so that the sensitive core block is tightly connected with the stainless steel tube shell. Temperature measurement nodes are refreshed in a grinding mode, long-term and repeated use of the tungsten-rhenium thermocouple in an erosion environment and a high-temperature aerobic environment is achieved, and meanwhile the preparation efficiency is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of sensor preparation, and in particular to a process for preparing an "erosion type" tungsten-rhenium thermocouple. Background Art

[0002] As science and technology develops towards high-end manufacturing, accurate measurement of the temperature in corrosive environments is urgent. For example, in specific harsh environments such as explosion fields and scramjet tail flame jets, the temperature in corrosive environments exceeds 2000°C and is accompanied by high pressure, severe vibration, strong flushing gas and other factors. Existing sensor measurement technologies are difficult to meet these requirements.

[0003] Tungsten-rhenium thermocouples are widely used in metallurgy, industrial control, aerospace and other fields due to their low price, superior thermoelectric potential performance and high thermal stability. Compared with other thermocouples, tungsten-rhenium thermocouples can work at extremely high temperatures, usually above 2000 degrees Celsius. However, conventional tungsten-rhenium thermocouples, including wire junctions, bead junctions, film junctions, etc., will fatigue or break under high temperature, high pressure and severe vibration in corrosive environments.

[0004] At present, in order to solve the problem that tungsten-rhenium thermocouples cannot withstand corrosive environments, academia and industry have proposed a variety of solutions, such as coating the surface of thermocouples with high-temperature resistant ceramic coatings to prevent them from being directly eroded by high-temperature airflow, and adding metal or ceramic protection tubes to the outside of thermocouples to provide additional mechanical support and thermal barriers. Although these methods have improved the corrosion resistance of tungsten-rhenium thermocouples to a certain extent, they have not completely solved the problem of greatly reduced service life in corrosive environments. Summary of the invention

[0005] The invention provides a process for preparing an "erosion type" tungsten-rhenium thermocouple to solve the problem that the tungsten-rhenium thermocouple cannot resist oxidation.

[0006] In order to solve the above technical problems, one of the purposes of the present invention is to provide a process for preparing an "erosion type" tungsten-rhenium thermocouple, and the specific steps are as follows:

[0007] S1: Sensitive core preparation process: Use an electric grinder to grind the tungsten sheet and tungsten-rhenium alloy sheet to remove stains on the surface to make it smooth, and then weld the tungsten wire and tungsten sheet, tungsten-rhenium alloy wire and tungsten-rhenium alloy sheet together through resistance welding to form the positive and negative electrodes of the "erosion type" tungsten-rhenium thermocouple;

[0008] S2: Sensitive core sintering process, in which alumina sheet, tungsten sheet, alumina sheet, tungsten-rhenium alloy sheet and alumina sheet are arranged in sequence to form a five-layer sensitive core structure, the five-layer sensitive core structure is pressed by a fixture, and placed in a tube furnace for hot pressing and sintering to form a sensitive core block;

[0009] S3: Encapsulation tube shell assembly process: Apply high-temperature glue to the alumina sheets on both sides of the sensitive core block, insert them into the stainless steel tube shell, and use a hot air gun to cure the high-temperature glue to make the sensitive core block and the stainless steel tube shell tightly connected.

[0010] Furthermore, the S1 sensitive core preparation process includes:

[0011] S11: Use a grinder to assemble 500-mesh, 1000-mesh, and 2000-mesh sandpaper circles in sequence to grind both sides of the tungsten sheet and the tungsten-rhenium alloy sheet until the surface is smooth;

[0012] S12: setting resistance welding current parameters, and welding the polished tungsten sheet and the tungsten-rhenium alloy sheet to the tungsten wire and the tungsten-rhenium alloy wire respectively to form thermocouple electrodes.

[0013] Furthermore, the S2 sensitive core sintering process specifically includes:

[0014] S21: Prepare a five-layer sensitive core structure, take the lower aluminum oxide sheet 5 and place it on the bottom layer, place the tungsten sheet 1 connected with the tungsten wire 2 on the lower aluminum oxide sheet 5, overlap the two, and align the end faces, then place the middle aluminum oxide sheet 6 on the tungsten sheet 1, place the tungsten-rhenium alloy sheet 3 connected with the tungsten-rhenium alloy wire 4 on the middle aluminum oxide sheet 6, and finally place the upper aluminum oxide sheet 7 on the tungsten-rhenium alloy sheet 3, to form a five-layer sensitive core structure 8;

[0015] S22: Place the five-layer sensitive core structure prepared in S21 in the designed alumina corundum fixture, tighten the screws on both sides of the fixture until the screws cannot be rotated, and the fixture compacts the five-layer sensitive core structure;

[0016] S23: Place the fixture of S22 with the compacted five-layer sensitive core structure into a tubular furnace, use an argon bottle to ventilate the tubular furnace to exhaust all the oxygen in the furnace, adjust the air pressure valve to control the air intake rate, and after sintering, the five-layer sensitive core structure particles are bonded and rearranged, and adhere to each other to form a sensitive structure block.

[0017] Furthermore, the S23 tubular furnace has a starting temperature of 25°C, a heating rate of 10°C / min in the range of 25°C-1200°C, a heating rate of 5°C / min in the range of 1200°C-1600°C, and is kept at 1600°C for 2 hours, followed by natural cooling. After the temperature drops to room temperature, the air pressure valve is closed to stop the flow of argon.

[0018] Furthermore, after the S2 five-layer sensitive core structure 8 is subjected to the above-mentioned hot pressing sintering, the bonding and rearrangement between the particles of the layers are completed, the volume is shrunk, the density is improved, the strength is increased, and they are bonded to each other to form a sensitive core block 13. The upper alumina sheet 7 and the lower alumina sheet 5 are sintered to form alumina layers on the upper and lower surfaces of the sensitive core block 13.

[0019] Furthermore, the S3 package shell assembly process specifically includes:

[0020] S31: Apply high temperature glue to the alumina layers on the upper and lower surfaces of the sensitive core block 13. The high temperature glue cures slowly at room temperature. Insert the sensitive core block 13 from the top of the stainless steel package tube shell 14, and lead the tungsten wire 2 and the tungsten-rhenium alloy wire 4 from the bottom of the stainless steel package tube shell 14.

[0021] S32: using a hot air gun to heat the sensitive core block 13 located at the top of the stainless steel packaging tube shell 14, the high temperature glue on the upper and lower surfaces of the sensitive core block 13 expands and solidifies due to the heat, and the sensitive core block 13 is bonded to the stainless steel packaging tube shell 14;

[0022] S33: Introduce high temperature glue into the syringe, use the syringe to fill the high temperature glue into the tail end of the stainless steel packaging tube shell 14 and the junction of the led tungsten wire 2 and the tungsten-rhenium alloy wire 4, and use a hot air gun to heat and cure the high temperature glue to form a high temperature glue block 15, so as to fix the position of the tungsten wire 2 and the tungsten-rhenium alloy wire 4 without shaking;

[0023] S34: grinding the sensitive core block 13 with an electric grinder. The metal particles generated by grinding the tungsten sheet layer and the tungsten-rhenium alloy layer of the sensitive core block 13 are bridged to each other to form a temperature measurement node.

[0024] The above one or more technical solutions of the present invention have at least one or more of the following technical effects: the process method for preparing "erosion type" tungsten-rhenium thermocouples provided by the present invention can quickly prepare "erosion type" tungsten-rhenium thermocouples with an upper limit of transient temperature measurement of 3000K, effectively improving the preparation efficiency. The prepared "erosion type" tungsten-rhenium thermocouples can be used in erosion environments (explosions, engine tail flame injection) and high-temperature aerobic environments. New temperature measurement nodes will be continuously and automatically generated during the erosion process, greatly improving the service life compared to traditional thermocouples. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 : Thermocouple electrode diagram;

[0026] Figure 2 : Five-layer sensitive core structure diagram;

[0027] Figure 3 : Sensitive core sintering fixture diagram;

[0028] Figure 4 : Overall structure diagram of "erosion type" tungsten-rhenium thermocouple;

[0029] Among them, 1-tungsten sheet, 2-tungsten wire, 3-tungsten-rhenium alloy sheet, 4-tungsten-rhenium alloy wire, 5-lower alumina sheet, 6-middle alumina sheet, 7-upper alumina sheet, 8-five-layer sensitive core structure, 9-upper corundum fixture, 10-lower corundum fixture, 11-left screw, 12-right screw, 13-sensitive core block, 14-stainless steel packaging tube shell, 15-high temperature rubber block. Specific implementation plan

[0030] The purpose of the present invention is to propose a process method for preparing an "erosion type" tungsten-rhenium thermocouple. The prepared "erosion type" tungsten-rhenium thermocouple has an upper limit of transient temperature measurement of 3000K, and the temperature measurement node can be refreshed by grinding, so that the tungsten-rhenium thermocouple can be used for a long time and repeatedly in an erosion environment and a high-temperature aerobic environment, while effectively improving the preparation efficiency.

[0031] The technical solution adopted by the present invention is as follows:

[0032] A process for preparing an "erosion type" tungsten-rhenium thermocouple includes a sensitive core preparation process, a sensitive core sintering process and a packaging tube shell assembly process.

[0033] The sensitive core preparation process uses an electric grinder to grind the tungsten sheet and the tungsten-rhenium alloy sheet under 500-mesh, 1000-mesh, and 2000-mesh sandpaper circles to make their surfaces smooth, and the tungsten-rhenium alloy wire is placed in the middle of the wide side of the tungsten-rhenium alloy sheet, and the tungsten-rhenium alloy wire is controlled to extend 10 mm into the tungsten-rhenium alloy sheet. The 10 mm contact area of ​​the tungsten-rhenium alloy wire and the tungsten-rhenium alloy sheet is welded by resistance welding. After welding, the tungsten-rhenium alloy sheet and the tungsten-rhenium alloy wire are integrated to form the negative electrode of the thermocouple. Similarly, the tungsten sheet and the tungsten wire are welded together to form the positive electrode of the thermocouple.

[0034] The sensitive core sintering process is as follows: alumina sheet, tungsten sheet, alumina sheet, tungsten-rhenium alloy sheet, and alumina sheet are stacked in order to form a five-layer sensitive core structure, with the end faces of the layers aligned and overlapped. The five-layer sensitive core structure is placed in a designed alumina corundum fixture, and pressure is applied to the five-layer sensitive core structure by tightening the screws on both sides of the fixture. The structure is placed in a tubular furnace and sintered at 1600°C for 2 hours. Argon is introduced throughout the process to create an oxygen-free environment. The five-layer sensitive core structure is hot-pressed and sintered to form a sensitive core block.

[0035] In the packaging tube shell assembly process, the two sides of the sensitive core block are alumina sheets. The high-temperature glue is evenly applied to the alumina sheets on both sides to form a high-temperature glue film, which is then inserted into the stainless steel tube shell. A hot air gun is used to heat and solidify and expand the high-temperature glue film to fill the gap between the sensitive core block and the stainless steel tube shell. A syringe is used to inject the high-temperature glue into the tail of the stainless steel tube and the junction of the two exposed tungsten wires and tungsten-rhenium alloy wires. A hot air gun is used to solidify the high-temperature glue so that the tungsten wire and tungsten-rhenium alloy wire cannot shake. An electric grinder is used to grind the sensitive core block to form a temperature measurement node.

[0036] Based on the above, through the preparation process provided by the present invention, the preparation efficiency and yield of tungsten-rhenium thermocouples can be effectively improved without expensive production costs and complex preparation technology. In a corrosive environment, when the old temperature measuring node fails due to oxidation, the sensitive core can automatically generate a new temperature measuring node accompanied by air flow flushing. Compared with other thermocouples, the thermocouple obtained by this preparation process greatly improves the service life in a high-temperature aerobic environment and a corrosive process.

[0037] A process for preparing an "erosion type" tungsten-rhenium thermocouple comprises the following steps:

[0038] The sensitive core preparation process uses an electric grinder to grind the tungsten sheet and the tungsten-rhenium alloy sheet to remove stains on the surface to make it smooth, and then the tungsten wire and the tungsten sheet, the tungsten-rhenium alloy wire and the tungsten-rhenium alloy sheet are welded together by resistance welding to form the positive and negative electrodes of the "erosion type" tungsten-rhenium thermocouple;

[0039] The sensitive core sintering process is to arrange the aluminum oxide sheet, the tungsten sheet, the aluminum oxide sheet, the tungsten-rhenium alloy sheet, and the aluminum oxide sheet in sequence to form a five-layer sensitive core structure, and to apply pressure to the five-layer sensitive core structure through a fixture, and to place the five-layer sensitive core structure in a tube furnace for hot pressing and sintering to form a sensitive core block;

[0040] In the packaging tube shell assembly process, the aluminum oxide sheets on both sides of the sensitive core block are coated with high-temperature glue, inserted into the stainless steel tube shell, and the high-temperature glue is cured with a hot air gun to tightly connect the sensitive core block and the stainless steel tube shell.

[0041] The sensitive core preparation process includes using a grinder to sequentially assemble 500-mesh, 1000-mesh, and 2000-mesh sandpaper circles to grind both sides of a tungsten sheet and a tungsten-rhenium alloy sheet until the surface is smooth.

[0042] The sensitive core preparation process includes setting resistance welding current parameters, welding the polished tungsten sheet and the tungsten-rhenium alloy sheet to the tungsten wire and the tungsten-rhenium alloy wire respectively to form thermocouple electrodes.

[0043] The sensitive core sintering process includes overlapping and stacking an aluminum oxide sheet, a tungsten sheet, an aluminum oxide sheet, a tungsten-rhenium alloy sheet, and an aluminum oxide sheet in order to form a five-layer sensitive core structure, wherein two metal sheets are connected to metal wires.

[0044] The sensitive core sintering process includes placing the five-layer sensitive core structure in a designed alumina corundum fixture, tightening screws on both sides of the fixture until the screws cannot be rotated, and the fixture tightly compacts the five-layer sensitive core structure.

[0045] The sensitive core sintering process includes placing a fixture with a compacted five-layer sensitive core structure into a tubular furnace, using an argon bottle to ventilate the tubular furnace to exhaust oxygen in the furnace, and adjusting a gas pressure valve to control the air intake rate.

[0046] The sensitive core sintering process includes setting the starting temperature of the tubular furnace to 25°C, heating the temperature at a rate of 10°C / min in the range of 25°C-1200°C, heating the temperature at a rate of 5°C / min in the range of 1200°C-1600°C, keeping the temperature at 1600°C for 2 hours, then cooling naturally, and closing the air pressure valve after the temperature drops to room temperature. After sintering, the five layers of sensitive core structure particles are bonded and rearranged, and bonded to each other to form a sensitive structure block.

[0047] The packaging tube shell assembly process includes: applying high-temperature glue to the alumina sheets on both sides of the sensitive core block, the high-temperature glue is not solidified at room temperature, and the sensitive core block is inserted into the 304 stainless steel tube shell. There is a small gap between the sensitive core block and the 304 stainless steel tube. A hot air gun is used to heat and solidify the high-temperature glue applied on the alumina sheets. The high-temperature glue expands due to heat and fills the gap between the sensitive core block and the stainless steel tube shell.

[0048] The packaging tube shell assembly process includes: loading high temperature glue into a syringe, using the syringe to fill the high temperature glue at the junction of the tail of the stainless steel tube and the two exposed tungsten-rhenium alloy wires, using a hot air gun to heat and cure the high temperature glue, and fixing the position of the tungsten wire and the tungsten-rhenium alloy wire.

[0049] The packaging tube shell assembly process includes using an electric grinder to grind the exposed surface of the sensitive core block, and grinding the sensitive core block to produce tungsten particles and tungsten-rhenium particles that bridge each other to form temperature measurement nodes.

[0050] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in combination with the embodiments of the present invention and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the obtained embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0051] The present application is further described in detail below in conjunction with the accompanying drawings.

[0052] A process for preparing an "erosion type" tungsten-rhenium thermocouple comprises the following steps:

[0053] Step 1: Assemble the electric grinder drill bit with a 500-mesh sandpaper ring, and grind both sides of the tungsten sheet 1 and the tungsten-rhenium alloy sheet 3. Replace the 1000-mesh and 2000-mesh sandpaper rings in turn, and repeat the above operation. After grinding, the surface of the tungsten sheet 1 and the tungsten-rhenium alloy sheet 3 is smooth and free of impurities;

[0054] Step 2: Put the tungsten sheet 1 and the tungsten wire 2 into the welding port of the electric welder. The tungsten wire 2 is placed at the center of the upper surface of the tungsten sheet 1. The length of the tungsten wire 2 on the upper surface of the tungsten sheet 1 is controlled to be 10 mm. Select the resistance welding function of the electric welder, set the current parameters, and weld the 10 mm overlapping area of ​​the tungsten wire 2 and the tungsten sheet 1. After welding, the tungsten sheet 1 and the tungsten wire 2 are connected to form the positive electrode of the thermocouple. Repeat the above steps to connect the tungsten-rhenium alloy sheet 3 and the tungsten-rhenium alloy wire 4 to form the negative electrode of the thermocouple.

[0055] Step 3: Take the lower alumina sheet 5 and place it on the bottom layer, place the tungsten sheet 1 connected with the tungsten wire 2 on the lower alumina sheet 5, overlap the two, and align the end faces, and so on, then place the middle alumina sheet 6 on the tungsten sheet 1, place the tungsten-rhenium alloy sheet 3 connected with the tungsten-rhenium alloy wire 4 on the middle alumina sheet 6, and finally place the upper alumina sheet 7 on the tungsten-rhenium alloy sheet 3, to form a five-layer sensitive core structure 8;

[0056] Step 4: Place the five-layer sensitive core structure 8 on the center of the surface of the lower corundum fixture 10, align the upper corundum fixture 9 with the lower corundum fixture 10, and wrap the five-layer sensitive core structure 8 with the two. Screw the left screw 11 and the right screw 12 into the threaded holes on the left and right sides of the upper corundum fixture 9, and screw them into the threaded holes on the left and right sides of the lower corundum fixture 10, respectively. By tightening the left screw 11 and the right screw 12, the upper corundum fixture 9 and the lower corundum fixture 10 are connected and tightened, thereby applying upper and lower pressures to the five-layer sensitive core structure 8 wrapped in the middle;

[0057] Step 5: Place the entire corundum fixture with the five-layer sensitive core structure 8 into the tubular furnace, use an argon bottle, open the air pressure valve to control the argon gas to enter the tubular furnace, and exhaust the oxygen in the furnace. Set the starting temperature of the tubular furnace to 25°C, and the heating rate in the range of 25°C-1200°C to 10°C / min, and the heating rate in the range of 1200°C-1600°C to 5°C / min. Keep warm at 1600°C for 2h, then cool down naturally. After the tubular furnace drops to room temperature, close the air pressure valve to stop the entry and exit of argon.

[0058] Step 6: After the five-layer sensitive core structure 8 is sintered by the hot pressing, the particles between the layers are bonded and rearranged, the volume shrinks, the density is improved, the strength is increased, and they are bonded to each other to form a sensitive core block 13. The upper alumina sheet 7 and the lower alumina sheet 5 are sintered to form alumina layers on the upper and lower surfaces of the sensitive core block 13. High-temperature glue is applied to the alumina layers on the upper and lower surfaces of the sensitive core block 13. The high-temperature glue solidifies slowly at room temperature. The sensitive core block 13 is inserted from the top of the stainless steel packaging tube shell 14, and the tungsten wire 2 and the tungsten-rhenium alloy wire 4 are led out from the bottom of the stainless steel packaging tube shell 14.

[0059] Step 7: Use a hot air gun to heat the sensitive core block 13 located at the top of the stainless steel packaging tube shell 14. The high-temperature glue on the upper and lower surfaces of the sensitive core block 13 expands and solidifies due to the heat, so that the sensitive core block 13 and the stainless steel packaging tube shell 14 are bonded.

[0060] Step 8: Introduce high-temperature glue into the syringe, and use the syringe to fill the high-temperature glue at the tail end of the stainless steel packaging tube shell 14 and the junction of the led tungsten wire 2 and the tungsten-rhenium alloy wire 4. Use a hot air gun to heat and cure the high-temperature glue to form a high-temperature glue block 15, thereby fixing the position of the tungsten wire 2 and the tungsten-rhenium alloy wire 4 without shaking.

[0061] Step 9: Use an electric grinder to grind the sensitive core block 13. The metal particles generated by grinding the tungsten sheet layer and the tungsten-rhenium alloy layer of the sensitive core block 13 are bridged to each other to form a temperature measurement node.

[0062] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

[0063] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if these modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A process for preparing an "erosion type" tungsten-rhenium thermocouple, characterized in that: The specific steps are as follows: S1: Sensitive core preparation process: Use an electric grinder to grind the tungsten sheet and tungsten-rhenium alloy sheet to remove stains on the surface to make it smooth, and then weld the tungsten wire and tungsten sheet, tungsten-rhenium alloy wire and tungsten-rhenium alloy sheet together through resistance welding to form the positive and negative electrodes of the "erosion type" tungsten-rhenium thermocouple; S2: Sensitive core sintering process, in which alumina sheet, tungsten sheet, alumina sheet, tungsten-rhenium alloy sheet and alumina sheet are arranged in sequence to form a five-layer sensitive core structure, the five-layer sensitive core structure is pressed by a fixture, and placed in a tube furnace for hot pressing and sintering to form a sensitive core block; S3: Encapsulation tube shell assembly process: Apply high-temperature glue to the alumina sheets on both sides of the sensitive core block, insert them into the stainless steel tube shell, and use a hot air gun to cure the high-temperature glue to make the sensitive core block and the stainless steel tube shell tightly connected.

2. The process for preparing an "erosion type" tungsten-rhenium thermocouple according to claim 1, characterized in that: The S1 sensitive core preparation process includes: S11: Use a grinder to assemble 500-mesh, 1000-mesh, and 2000-mesh sandpaper circles in sequence to grind both sides of the tungsten sheet and the tungsten-rhenium alloy sheet until the surface is smooth; S12: setting resistance welding current parameters, and welding the polished tungsten sheet and the tungsten-rhenium alloy sheet to the tungsten wire and the tungsten-rhenium alloy wire respectively to form thermocouple electrodes.

3. The process for preparing an "erosion type" tungsten-rhenium thermocouple according to claim 1, characterized in that: The S2 sensitive core sintering process specifically includes: S21: Prepare a five-layer sensitive core structure, take the lower aluminum oxide sheet (5) and place it on the bottom layer, place the tungsten sheet (1) connected with the tungsten wire (2) on the lower aluminum oxide sheet (5), overlap the two, and align the end faces, then place the middle aluminum oxide sheet (6) on the tungsten sheet (1), place the tungsten-rhenium alloy sheet (3) connected with the tungsten-rhenium alloy wire (4) on the middle aluminum oxide sheet (6), and finally place the upper aluminum oxide sheet (7) on the tungsten-rhenium alloy sheet (3), so as to form a five-layer sensitive core structure (8); S22: Place the five-layer sensitive core structure prepared in S21 in the designed alumina corundum fixture, tighten the screws on both sides of the fixture until the screws cannot be rotated, and the fixture compacts the five-layer sensitive core structure; S23: Place the fixture of S22 with the compacted five-layer sensitive core structure into a tubular furnace, use an argon bottle to ventilate the tubular furnace to exhaust all the oxygen in the furnace, adjust the air pressure valve to control the air intake rate, and after sintering, the five-layer sensitive core structure particles are bonded and rearranged, and adhere to each other to form a sensitive structure block.

4. The process for preparing an "erosion type" tungsten-rhenium thermocouple according to claim 3, characterized in that: The S23 tubular furnace has a starting temperature of 25°C, a heating rate of 10°C / min in the range of 25°C-1200°C, a heating rate of 5°C / min in the range of 1200°C-1600°C, and is kept at 1600°C for 2 hours, followed by natural cooling. After the temperature drops to room temperature, the air pressure valve is closed to stop the flow of argon.

5. The process for preparing an "erosion type" tungsten-rhenium thermocouple according to claim 1, characterized in that: After the hot pressing sintering, the S2 five-layer sensitive core structure (8) completes bonding and rearrangement between the particles of the layers, shrinks in volume, increases in density, and strengthens, and adheres to each other to form a sensitive core block (13). The upper alumina sheet (7) and the lower alumina sheet (5) are sintered to form alumina layers on the upper and lower surfaces of the sensitive core block (13).

6. The process for preparing an "erosion type" tungsten-rhenium thermocouple according to claim 1, characterized in that: The S3 package shell assembly process specifically includes: S31: Apply high temperature glue to the alumina layers on the upper and lower surfaces of the sensitive core block (13), the high temperature glue solidifies slowly at room temperature, insert the sensitive core block (13) from the top of the stainless steel packaging tube shell (14), and lead the tungsten wire (2) and the tungsten-rhenium alloy wire (4) out from the bottom of the stainless steel packaging tube shell (14); S32: using a hot air gun to heat the sensitive core block (13) located at the top of the stainless steel packaging tube shell (14), so that the high-temperature glue on the upper and lower surfaces of the sensitive core block (13) expands and solidifies due to the heat, thereby bonding the sensitive core block (13) to the stainless steel packaging tube shell (14); S33: introducing high temperature glue into a syringe, using the syringe to fill the high temperature glue at the tail end of the stainless steel packaging tube shell (14) and the junction of the led tungsten wire (2) and the tungsten-rhenium alloy wire (4), and using a hot air gun to heat and cure the high temperature glue to form a high temperature glue block (15), thereby fixing the position of the tungsten wire (2) and the tungsten-rhenium alloy wire (4) to prevent shaking; S34: grinding the sensitive core block (13) using an electric grinder, so that the metal particles generated by grinding the tungsten sheet layer and the tungsten-rhenium alloy layer of the sensitive core block (13) are bridged to each other, forming a temperature measurement node.

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