PTC ceramic heating assembly with superhigh temperature resistance and preparation method thereof

Abstract

The application relates to a super-high-temperature-resistant PTC ceramic heating assembly and a preparation method thereof. The super-high-temperature-resistant PTC ceramic heating assembly comprises a PTC ceramic column with a groove structure, a first metal electrode layer, a high-temperature-resistant wire, a second metal electrode layer for filling the groove structure and an anti-oxidation layer which are sequentially distributed on the surface of the groove structure of the PTC ceramic column; the super-high-temperature-resistant PTC ceramic heating assembly further comprises an outer shell and insulating heat-conducting glue which is distributed between the outer shell and the PTC ceramic column with the groove structure.

Description

Technical Field

[0001] This invention relates to a PTC ceramic heating component resistant to ultra-high temperatures and its preparation method, specifically to a PTC heating component resistant to ultra-high temperatures for use in confined spaces and its preparation method, belonging to the field of electronic ceramic materials and components. Background Technology

[0002] PTC ceramic material is a semiconducting ferroelectric ceramic that exhibits a step increase in resistance above the Curie temperature due to a phase transition. This excellent resistance-temperature characteristic makes it widely used in various types of constant-temperature heaters. In addition, PTC ceramic heaters have low power consumption and do not require additional temperature control devices, making them ideal for use in confined spaces.

[0003] In PTC (Potentially Transmitted Temperature) heating applications, high-temperature external environments are frequently encountered. For example, when PTCs are used in spaceborne external CCD cameras, they encounter space particle effects (such as gamma-ray bursts) in deep space, accompanied by a sharp rise in ambient temperature. PTCs used in deep-sea exploration devices experience extreme high-temperature environments from deep-sea hydrothermal vents. PTC self-regulating heating belts are commonly used in high-voltage power lines; in cases of abnormal discharge, a significant temperature increase can occur in a short period within a localized area. In automotive and aerospace engines, PTC temperature control devices are commonly used to maintain the liquid fuel temperature within a preset range; however, after fuel combustion, the ambient temperature around the PTC heater also rises sharply. Under these conditions, the ambient temperature can rise to several hundred or even nearly a thousand degrees Celsius.

[0004] Chinese Patent 1 (CN210317528U) discloses a PTC heating temperature control device for automotive fuel engines, solving problems such as engine starting difficulties and engine stalling while driving. Chinese Patent 2 (Publication No. CN101586720A) discloses an oil pipe assembly for connecting to an aircraft engine fuel servo system and its manufacturing method, requiring it to withstand short-term high temperatures of 1100±80℃ without failure. However, neither of these high-temperature application scenarios mentions the operating status of the thermostat itself in high-temperature environments. Whether the thermostat heater can function properly and whether its internal components can withstand high temperatures are currently unreported. Summary of the Invention

[0005] To address the high-temperature resistance issues of existing PTC thermostats in certain applications, this invention aims to provide a PTC ceramic heating element that combines intelligent thermostat heating with ultra-high temperature resistance. The PTC heating element prepared using this method can ensure that the object is heated to a specified temperature, and the element can withstand temperatures above 1000℃. Its space-saving design eliminates the need for additional temperature control devices, and its low power consumption significantly reduces the system load.

[0006] On one hand, the present invention provides an ultra-high temperature resistant PTC ceramic heating assembly, comprising: a PTC ceramic column with a groove structure, and a first metal electrode layer, a high-temperature resistant wire, a second metal electrode layer connecting the first metal electrode layer and the high-temperature resistant wire and used to fill the groove structure, and an anti-oxidation layer sequentially distributed on the surface of the groove structure of the PTC ceramic column; the ultra-high temperature resistant PTC ceramic heating assembly further comprises an outer shell, and an insulating thermally conductive adhesive distributed between the outer shell and the PTC ceramic column with the groove structure.

[0007] In this invention, the principle behind improving the ultra-high temperature resistance of the PTC ceramic heating element lies in the use of high-temperature resistant materials in all parts of the element, particularly replacing the traditional silver electrode material with the PTC ceramic electrode material. Furthermore, the electrodes (first and second metal electrode layers) are connected to the high-temperature resistant wires using a repeated pouring and infiltration method, avoiding the factors of high-temperature insensitivity present in welding and other connection methods. Simultaneously, a high-temperature resistant inorganic adhesive is selected to ensure the stability of the encapsulation. The PTC ceramic heating element has low power consumption, is lightweight, and employs a space-saving recessed structure design, making it particularly suitable for heating and temperature control applications in confined spaces under high-temperature conditions.

[0008] Preferably, the PTC ceramic column with groove structure is composed of barium titanate-based PTC ceramic or vanadium oxide-based PTC ceramic; the Curie temperature of the PTC ceramic column with groove structure is 50–300°C.

[0009] Preferably, the cross-section of the PTC ceramic column with the groove structure is rectangular, and the groove structure is distributed on both sides of the PTC ceramic column; the groove opening cross-section of the groove structure is trapezoidal, hexagonal, or octagonal.

[0010] Preferably, the composition of the first metal electrode is selected from high-temperature metal materials that can withstand temperatures above 1000°C, and is more preferably selected from at least one of titanium, platinum, nickel and their alloys; the thickness of the first metal electrode is 0.02 mm to 0.5 mm.

[0011] Preferably, the second metal electrode is made of a high-temperature metal material that can withstand temperatures above 1000°C, and is preferably selected from at least one of platinum, nickel, titanium and their alloys.

[0012] Preferably, the material of the anti-oxidation layer is selected from inorganic compounds that can withstand high temperatures above 1000°C and are anti-oxidation, and is more preferably selected from at least one of aluminum nitride, titanium aluminum nitride, and chromium nitride.

[0013] Preferably, the insulating and thermally conductive adhesive is resistant to temperatures above 1000°C, and is preferably selected from at least one of the following: a combination adhesive of aluminosilicate and inorganic polymer, and a combination adhesive of silicate and heat-resistant resin. The aluminosilicate may be one or more of potassium aluminosilicate, sodium aluminosilicate, lithium aluminosilicate, magnesium aluminosilicate, etc.; the inorganic polymer may be a polymer containing -Si-O-Si- bonds or -Si-O-Al-O- bonds, prepared from glass powder, kaolinite, sodium hydroxide, and sodium silicate aqueous solution in a specific ratio of 1:1 to 3:5 to 15:5 to 15. The silicate may be one or more of magnesium silicate, lithium silicate, etc.; the heat-resistant resin may be methylphenyl silicone resin, modified phenolic resin, etc.

[0014] Preferably, the material of the outer shell is resistant to high temperatures above 1000°C; the shape of the outer shell is cylindrical or cuboid; the material of the outer shell is selected from 310S stainless steel, cobalt-based high-temperature alloy or nickel-chromium-iron-based reinforced alloy.

[0015] Preferably, the material of the high-temperature resistant conductor is resistant to temperatures above 1000°C, and is preferably selected from at least one of metals such as platinum, rhodium, and nickel and their alloys.

[0016] On the other hand, the present invention provides a method for preparing an ultra-high temperature resistant PTC ceramic heating component, comprising:

[0017] (1) Grooving is performed on the surface of the PTC ceramic column according to the groove design to obtain a PTC ceramic column with a groove structure;

[0018] (2) A first metal electrode layer is fabricated on the groove surface of a PTC ceramic column with a groove structure;

[0019] (3) Place the PTC ceramic column with the first metal electrode layer prepared in a designated mold, pour in the second metal electrode slurry and simultaneously embed the high-temperature wire into it, dry and fire it multiple times to obtain the second metal electrode layer.

[0020] (4) An anti-oxidation layer is formed on the surface of the second metal electrode layer;

[0021] (5) Place the obtained PTC ceramic column covered with an anti-oxidation layer into the shell and inject insulating and thermally conductive potting compound to obtain an ultra-high temperature resistant PTC ceramic heating component.

[0022] Beneficial effects:

[0023] In this invention, all components and parts are made of high-temperature resistant materials, improving the reliability of the overall PTC module in extreme high-temperature environments. The connection method adopts repeated sintering molding, avoiding the factors in traditional welding molding processes where certain materials and processes are not resistant to high temperatures. Through the design of a series of Curie temperature PTC material formulations, heating requirements under different temperature control applications can be met. The selection of high-temperature resistant insulating and thermally conductive adhesive improves the reliability of the encapsulation. The PTC ceramic body adopts a groove structure design, with the electrodes built into it, saving space, protecting the metal electrodes, and enhancing the sintering processability. The module has low power consumption during operation, reducing system load and electrical load. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the shape and dimensions of the PTC ceramic column in Embodiment 1 of the present invention. The ceramic column has grooves on both sides, and the groove cross-section is trapezoidal.

[0025] Figure 2 This is a three-dimensional schematic diagram of the sample prepared in Embodiment 1 of the present invention;

[0026] Figure 3 This is a schematic diagram of the longitudinal section of the sample from Example 1;

[0027] Figure 4 This is a schematic diagram of the transverse cross-section of the sample in Example 1. Detailed Implementation

[0028] The present invention will be further illustrated by the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0029] This invention proposes a high-temperature resistant and low-power PTC heating element suitable for use in confined spaces. This ultra-high temperature resistant PTC ceramic heating element comprises: a PTC ceramic pillar with a grooved structure, a first metal electrode layer, a second metal electrode layer, a high-temperature resistant wire, an anti-oxidation layer, an insulating thermally conductive adhesive, and a housing. All parts of the ultra-high temperature resistant PTC ceramic heating element provided by this invention are made of high-temperature resistant materials, and the electrode structure design saves space, allowing it to operate in confined environments exceeding 1000°C. Compared with traditional heating elements, the PTC ceramic heating element prepared using the method of this invention is lightweight, consumes less power, is structurally particularly suitable for confined installation spaces, and possesses high-temperature resistance, making it suitable for use in high-temperature environments.

[0030] The first metal electrode layer is coated on the surface of the ceramic column groove, and the second metal electrode layer connects the first metal electrode layer to the high-temperature wire.

[0031] In an optional embodiment, the second metal electrode layer can completely fill the ceramic pillar groove and be flush with the groove surface before an anti-oxidation layer is prepared. Alternatively, the second metal electrode layer can partially fill the ceramic pillar groove, and then an anti-oxidation layer is prepared and flush with the groove surface.

[0032] In one embodiment of the present invention, the preparation method of the ultra-high temperature resistant PTC ceramic heating component includes steps such as PTC ceramic raw material powder formulation control, molding and sintering, machining, electrode fabrication, wire connection, and potting.

[0033] A PTC ceramic material formulation is designed, and a ceramic forming process is used to produce ceramic sheets with a specified Curie temperature. The PTC ceramic material includes, but is not limited to, barium titanate-based PTC ceramics and vanadium oxide-based PTC ceramics. The resulting PTC ceramic sheets have a Curie temperature range of 50-300℃.

[0034] As an example of PTC ceramic sheet preparation, the process includes: weighing raw materials such as BaCO3, TiO2, CaCO3, Y2O3, Nb2O5, SrCO3, Pb3O4, and V2O5 according to a given stoichiometric ratio, ball milling them in a mixing drum, drying them in an oven, and then synthesizing them in a high-temperature electric furnace. SrCO3 and Pb3O4 are Curie temperature modifiers, and one or more can be selectively added as needed. Preferably, the material:ball:anhydrous ethanol ratio during mixing drum ball milling is 1:3:1.5-4.5, the ball milling speed is 550-650 r / min, the ball milling time is 20-24 hours, and the drying temperature after ball milling is 70℃-90℃. The preferred synthesis process conditions are 1140℃-1160℃ for 2 hours. The synthesized base powder and trace dopants Al2O3, SiO2, and MnCO3 are weighed according to a given stoichiometric ratio, placed in a ball mill, dried in an oven, and pre-fired in a high-temperature electric furnace. Preferably, during ball milling, the ratio of material:balls:anhydrous ethanol is 1:3:0.8-1.5, the milling speed is 550-650 r / min, the milling time is 22-24 hours, and the drying temperature after milling is 70℃-90℃. The preferred pre-firing conditions are 900℃-1100℃ for 2 hours. A certain amount of PVA is added to the obtained PTC ceramic raw material to granulate it, and then pressed into a green body; preferably, the PVA addition is in the range of 5wt%-9wt%; the pre-pressing pressure is 1-1.5T / cm during dry pressing. 2 The holding time is 1-5 minutes, and the cold isostatic pressing pressure is 2-5 T / cm. 2 The holding time is 5-10 minutes; the obtained PTC ceramic blank is placed in a high-temperature electric furnace to remove the binder, and then sintered into ceramic components. Preferably, the binder removal process is carried out at 600-800℃ for 2 hours, and the sintering process is carried out at 1300℃-1360℃ for 1-2 hours, followed by natural cooling with the furnace.

[0035] PTC ceramic sheets are machined into ceramic pillars of a specified shape and size, and grooves are cut into the surface according to the groove design. The ceramic pillars are grooved on both sides, and the groove cross-section can be, but is not limited to, trapezoidal, hexagonal, octagonal, etc. The PTC ceramic sheets are machined into ceramic pillars of a specified shape and size using, but is not limited to, wire cutting, CNC machining, etc. In this invention, the groove structure design mainly considers the following points: 1. Space saving: Previously, PTC electrodes were externally plated. In such confined space applications, using a recessed structure to prepare the electrode is beneficial for space utilization; 2. Electrode layer protection: The ceramic body can withstand temperatures above 1000℃, and enclosing most of the electrode layer within the groove is more conducive to protecting the electrode layer; 3. The groove structure facilitates the casting and molding of the second metal electrode layer metal paste and can assist in the positioning of the metal wire using a high-temperature metal wire fixture.

[0036] A first metal electrode layer is fabricated on the surface of a grooved ceramic column. The thickness of the first metal electrode layer can be 0.02-0.5 mm. The first metal electrode layer is prepared using a high-temperature resistant metal material that can withstand temperatures above 1000℃, including but not limited to titanium, platinum, nickel, and their alloys. The preparation methods for the first metal electrode layer include, but are not limited to, electrode processes such as sputtering and ion plating. The first metal electrode layer primarily forms an ohmic contact with the ceramic body. Previously, silver paste was mostly used for screen printing, but this method cannot withstand high temperatures. To solve the problem of both high-temperature resistance and ohmic contact formation, this invention uses high-temperature resistant metals such as titanium, platinum, nickel, and their alloys. For such metals (e.g., platinum), good ohmic contact is not easily formed using screen printing; therefore, vacuum sputtering is used to prepare the electrode, which is beneficial for ohmic contact formation.

[0037] A PTC ceramic column with a prepared first metal electrode layer is placed in a designated mold, and a second metal electrode slurry is poured in while simultaneously embedding a high-temperature wire. After drying, the mold is fired multiple times to obtain the second metal electrode layer. This second metal electrode layer, with a thickness of 0.5-2 mm, is used to fill the groove space. The second metal electrode layer is prepared using a high-temperature resistant metal material (those resistant to temperatures above 1000℃), including but not limited to platinum, nickel, titanium, and their alloys. The preparation method of the second metal electrode layer includes, but is not limited to, multiple pouring and firing processes. The wire, resistant to temperatures above 1000℃, is used to connect the second metal electrode layer and the excitation power supply. Its material can be, but is not limited to, platinum, rhodium, nickel, and their alloys. The connection method between the wire and the electrode layer is, but is not limited to, repeated firing and infiltration molding. The material of the second metal electrode layer is mainly used to ensure the roughness of the electrode surface and to achieve the connection with the high-temperature wire (welding, etc.). Previous technologies have used silver paste layers that are not resistant to high temperatures, and the welding materials used for welding cannot achieve reliable connections at high temperatures. Therefore, there are connection problems between the high-temperature resistant metal slurry and the electrode material. Therefore, this invention innovatively uses a high-temperature metal slurry injection and embedding of high-temperature wires for repeated burning and seepage connection, avoiding the factors that cannot withstand high temperatures in welding and other connection processes.

[0038] As an example of the preparation of the second metal electrode layer, the aforementioned PTC ceramic column is placed in a designated mold, and metal slurry is poured into the grooves on both sides. One side of the high-temperature wire is embedded in the metal slurry, and the other side of the wire is fixed to a designated fixture. Together, they are placed in a high-temperature sintering furnace to sinter the second metal electrode layer. The slurry pouring and sintering are repeated until the specified thickness is reached.

[0039] A high-temperature resistant oxide layer (i.e., an anti-oxidation layer) is fabricated on the surface of the second metal electrode layer. The anti-oxidation layer has a thickness of 0.05-1 mm and is made of inorganic compounds that can withstand temperatures above 1000℃ and are resistant to oxidation. It is also required to have a certain thermal conductivity. Materials such as aluminum nitride, titanium aluminum nitride, and chromium nitride can be used, but are not limited to these. The preparation methods include, but are not limited to, ceramic electrode processes such as chemical vapor deposition and sputtering. It is mainly used to enhance the protection of the second metal electrode layer.

[0040] The prepared PTC ceramic column covered with an anti-oxidation layer is placed in the shell and an insulating and thermally conductive potting compound is injected. This insulating and thermally conductive compound can withstand temperatures above 1000℃, has good sealing performance, good flowability, is easy to mold and clean, and has thermal conductivity and a suitable coefficient of thermal expansion. The material can be, but is not limited to, a combination of aluminosilicate and inorganic polymer, or a combination of silicate and heat-resistant resin. Traditionally, PTC potting compounds have used silicone rubber. However, silicone rubber carbonizes at 1000℃, leading to seal failure. Most high-temperature adhesives suffer from a trade-off between thermal conductivity and high-temperature resistance, affecting the heat transfer efficiency of components at high temperatures. To overcome these issues, this invention preferably uses one or more of the following: aluminosilicates, a combination of silicate and inorganic polymers, or a combination of silicate and heat-resistant resins. Adjusting the appropriate ratio (wherein the mass ratio of the aluminosilicate and inorganic polymer combination is (1–3.5):1, and the mass ratio of silicate to heat-resistant resin in the silicate and heat-resistant resin combination is (2–5.5):1) satisfies the requirements for potting and high-temperature resistance, while achieving excellent thermal conductivity. The outer shell can withstand temperatures above 1000℃, exhibits good thermal conductivity and high strength, and its shape can be designed according to actual conditions. Commonly, but not limited to, regular shapes such as cylinders and cuboids are available. Materials used include, but are not limited to, 310S stainless steel, cobalt-based high-temperature alloys, and nickel-chromium-iron-based reinforced alloys. As an example, a PTC ceramic component is placed in a pre-fabricated housing, and insulating thermally conductive adhesive is poured in at room temperature, allowing it to set for 24-48 hours. The shape and dimensions of the housing can be designed according to actual application requirements. A high-temperature inorganic adhesive is preferred for thermal conductivity.

[0041] This invention features a high-temperature resistant PTC ceramic heating element that saves space, consumes little power, is lightweight, and has materials that can withstand temperatures above 1000℃, making it suitable for heating applications in confined spaces under high-temperature conditions. The main structural innovations are as follows: 1. Unlike traditional welding and other connection methods, the element uses a high-temperature wire embedded in a high-temperature metal slurry for repeated infiltration to achieve connection with the electrode; 2. Unlike previous external electrode designs, this invention primarily uses an electrode-embedded groove structure, saving space while protecting the electrode layer and facilitating the casting and molding of the second metal electrode layer; 3. An additional high-temperature anti-oxidation layer is added to the existing PTC element structure to further enhance the element's stability at high temperatures.

[0042] The following examples further illustrate the present invention in detail. It should also be understood that the following examples are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below. The following description uses barium titanate-based PTC ceramics as an example for implementation.

[0043] Example 1:

[0044] (1) First, the raw materials such as BaCO3, TiO2, Pb3O4, CaCO3, and Y2O3 are mixed according to the designed chemical composition. 0.915 Pb 0.05 Ca 0.03 Y 0.005 Ti 1.01 O3 was weighed, and the weighed raw materials were placed into a ball mill barrel. Anhydrous ethanol was poured in, with the ratio of material:ball:anhydrous ethanol being 1:3:2. After mixing for 24 hours by ball milling (610 r / min), the mixture was placed in an 80℃ oven to dry. After being sieved through a 20-mesh sieve, the mixture was placed in a high-temperature electric furnace and kept at 1160℃ for 2 hours to synthesize.

[0045] (2) Weigh and mix the above-synthesized powder and trace dopants such as Al2O3, SiO2 and MnCO3 according to the mass percentage of synthesized powder: Al2O3: SiO2: MnCO3 = 99.4: 0.08: 0.45: 0.07. The ratio of material: ball: anhydrous ethanol is 1:3:1. After mixing for 24 hours by ball milling (601 r / min), dry it in an oven at 80℃. After sieving through a 20-mesh sieve, put it in a furnace and pre-calcine it at 1000℃ for 2 hours.

[0046] (3) The obtained PTC ceramic powder is granulated with a certain amount of PVA, sieved through a 40-mesh sieve, and then dry-pressed on a tablet press (pressure 1T / cm). 2 Pre-formed into circular sheets with a diameter of 35 mm and a thickness of 4 mm (holding time 1 min), and then cold isostatically pressed on an isostatic press (pressure 2 T / cm). 2 The PTC ceramic preform was obtained by holding the pressure for 5 minutes.

[0047] (5) Place the PTC ceramic blank into a high-temperature furnace and heat it to 700℃ at 2℃ / min. Hold it for 2 hours and then remove the glue.

[0048] (6) Continue to sinter at 1300℃ at 6℃ / min for 1 hour, and then cool naturally in the furnace to obtain PTC ceramic sheets;

[0049] (7) The above PTC ceramic sheet is machined into a ceramic column 1 of 2mm×2mm×20mm, and trapezoidal grooves with an upper bottom of 0.8mm, a lower bottom of 1mm, and a height of 0.3mm are machined on both sides;

[0050] (8) The outer surface of the ceramic column was covered with polyimide tape and placed on a sputtering platform. The first metal layer titanium alloy electrode 2 was prepared on both sides of the groove. The sputtering time was 60 minutes, and the thickness of the sputtered titanium alloy film was about 0.2 mm. Then the polyimide tape was cleaned up.

[0051] (9) Place the PTC ceramic column with the first metal electrode sputtered above into a hollow 2mm×2mm×20mm mold, pour in platinum slurry, embed the high-temperature platinum wire 3 into it, clamp it with a fixing clamp, and dry it in an 80℃ oven. Repeat this process until the thickness of the slurry reaches 0.3mm after drying.

[0052] (10) Place the dried PTC ceramic column in a reducing atmosphere furnace, introduce nitrogen, and heat it to 800℃ at 4℃ / min and hold for 2 hours to fire the second metal electrode 4.

[0053] (11) Based on the firing results of 10, repeat 9-10 until the sintered electrode reaches the specified thickness of 0.3 mm;

[0054] (12) Place the PTC ceramic column with the second metal layer prepared above on the sputtering platform and deposit an anti-oxidation aluminum titanium nitride coating 5 with a thickness of about 0.2 mm;

[0055] (13) A certain amount of aluminosilicate and inorganic polymer combined insulating and thermally conductive adhesive 6 (wherein the mass ratio of aluminosilicate to inorganic polymer is (1.5~2):1) is applied to the bottom and inner side of the cylindrical 310S stainless steel shell 7. After drying, the above ceramic column is placed in it and the aluminosilicate and inorganic polymer combined insulating and thermally conductive adhesive is poured in. After standing for 48 hours, the sample is obtained.

[0056] (14) The sample prepared above was tested at room temperature. The resistance was about 80Ω and the surface temperature was about 140℃ after being powered on with 28V.

[0057] (15) Place the above samples in a high-temperature furnace, heat to 1200℃ at 4℃ / min and hold for 30 minutes, then cool with the furnace. Repeat this cycle 5 times and then cool to room temperature. Take out the sample and test its performance. The resistance at room temperature is 76Ω, and the surface temperature of the sample is about 140℃ when energized at 28V. See Table 1 for specific parameters.

[0058] Table 1 shows the test data for some samples in Example 1:

[0059]

[0060]

[0061] The above embodiments are intended only to enable those skilled in the art to understand the design concept of the present invention and implement it accordingly, and should not be construed as limiting the present invention. Any modifications and variations made in accordance with the spirit of the present invention should be within the scope of protection of the claims.

Claims

1. A high-temperature resistant PTC ceramic heating element, characterized in that, include: The PTC ceramic column has a groove structure, and a first metal electrode layer, a high-temperature resistant wire, a second metal electrode layer connecting the first metal electrode layer and the high-temperature resistant wire and used to fill the groove structure are sequentially distributed on the surface of the groove structure of the PTC ceramic column, and an anti-oxidation layer formed on the surface of the second metal electrode layer; wherein, the groove structure is distributed along both sides of the PTC ceramic column; the second metal electrode layer is obtained by placing the PTC ceramic column with the first metal electrode layer prepared in a designated mold, pouring the second metal electrode slurry into the groove structure, and simultaneously embedding the high-temperature resistant wire therein, and then drying and firing it multiple times; the ultra-high temperature resistant PTC ceramic heating component is made of materials that can withstand temperatures above 1000℃. The ultra-high temperature resistant PTC ceramic heating assembly also includes an outer shell and an insulating thermally conductive adhesive distributed between the outer shell and the PTC ceramic column with a groove structure; wherein the ultra-high temperature resistant PTC ceramic heating assembly is obtained by placing the PTC ceramic column covered with an anti-oxidation layer in the outer shell and injecting the insulating thermally conductive adhesive. The PTC ceramic column with the groove structure is composed of barium titanate-based PTC ceramics or vanadium oxide-based PTC ceramics. The material of the anti-oxidation layer is resistant to high temperatures above 1000°C and is selected from at least one of aluminum nitride, titanium aluminum nitride, and chromium nitride; the insulating and thermally conductive adhesive is resistant to high temperatures above 1000°C and is selected from at least one of a combination adhesive of aluminosilicate and inorganic polymer, and a combination adhesive of silicate and heat-resistant resin.

2. The ultra-high temperature resistant PTC ceramic heating component according to claim 1, characterized in that, The Curie temperature of the PTC ceramic column with the groove structure is 50–300°C.

3. The ultra-high temperature resistant PTC ceramic heating component according to claim 1, characterized in that, The PTC ceramic column with groove structure has a rectangular cross-section, and the groove structure is distributed on both sides of the PTC ceramic column; the groove opening cross-section of the groove structure is trapezoidal, hexagonal or octagonal.

4. The ultra-high temperature resistant PTC ceramic heating component according to claim 1, characterized in that, The composition of the first metal electrode is selected from high-temperature metal materials that can withstand temperatures above 1000°C, and is selected from at least one of titanium, platinum, nickel and their alloys; the thickness of the first metal electrode is 0.02 mm to 0.5 mm.

5. The ultra-high temperature resistant PTC ceramic heating component according to claim 1, characterized in that, The second metal electrode is made of a high-temperature metal material that can withstand temperatures above 1000°C, and is selected from at least one of platinum, nickel, titanium and their alloys.

6. The ultra-high temperature resistant PTC ceramic heating component according to claim 1, characterized in that, The outer shell is made of a material that can withstand temperatures above 1000°C; the outer shell is cylindrical or rectangular; the material of the outer shell is selected from 310S stainless steel, cobalt-based high-temperature alloy, or nickel-chromium-iron-based reinforced alloy.

7. The ultra-high temperature resistant PTC ceramic heating assembly according to any one of claims 1-6, characterized in that, The high-temperature resistant conductor is made of a material that can withstand temperatures above 1000°C and is selected from at least one of metals such as platinum, rhodium, and nickel and their alloys.

8. A method for preparing an ultra-high temperature resistant PTC ceramic heating component according to any one of claims 1-7, characterized in that, include: (1) Grooving is performed on the surface of the PTC ceramic column according to the groove design to obtain a PTC ceramic column with a groove structure; (2) A first metal electrode layer is fabricated on the groove surface of a PTC ceramic column with a groove structure; (3) Place the PTC ceramic column with the first metal electrode layer prepared in the designated mold, pour in the second metal electrode slurry and embed the high temperature resistant wire in it at the same time, dry it and fire it repeatedly to obtain the second metal electrode layer. (4) An anti-oxidation layer is formed on the surface of the second metal electrode layer; (5) Place the obtained PTC ceramic column covered with an anti-oxidation layer into the outer shell and inject insulating and thermally conductive potting compound to obtain an ultra-high temperature resistant PTC ceramic heating component.

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