High-temperature-resistant corrosion-resistant full-temperature-range measurement ceramic temperature sensor and preparation method thereof

Abstract

The application discloses a high-temperature-resistant and corrosion-resistant full-temperature-range measuring ceramic temperature sensor and a preparation method thereof, and belongs to the technical field of temperature sensors.The high-temperature-resistant and corrosion-resistant full-temperature-range measuring ceramic temperature sensor comprises an ultrasonic sensing ceramic rod, one end of the ultrasonic sensing ceramic rod is sequentially provided with a crystallization orientation induction layer, a piezoelectric functional layer, a protective layer and a high-temperature-resistant electrode layer from inside to outside, and the piezoelectric functional layer is a (002) oriented columnar crystal AlScCrN coating.The application has the beneficial effect that the ceramic material is applied to temperature detection as a temperature sensor, the shortcomings that a traditional thermocouple has a slow response speed and cannot work in a corrosive environment are avoided, the ceramic temperature sensor can work from a low temperature of liquid nitrogen to a high temperature of 2500 DEG C, and the temperature measurement in a wide temperature range is realized for the first time.

Description

High-temperature resistant and corrosion-resistant full-temperature range ceramic temperature sensor and its preparation method Technical Field

[0001] This invention relates to the field of temperature sensor technology, and more specifically, to a high-temperature resistant, corrosion-resistant, full-temperature-range ceramic temperature sensor and its preparation method. Background Technology

[0002] Aero engines are highly complex and precise thermodynamic machines. As the heart of an aircraft, they not only power flight but also serve as a crucial driving force for the development of aviation. Every significant transformation in the history of human aviation has been inextricably linked to advancements in aero engine technology. After more than a century of development, aero engines have become highly reliable and mature products. Currently used aero engines include various types such as turbojet / turbofan engines, turboshaft / turboprop engines, ramjet engines, and piston engines. They power various military and civilian aircraft, drones, and cruise missiles. Furthermore, gas turbines derived from aero engines are widely used in ground power generation, marine propulsion, mobile power stations, and natural gas and oil pipeline pumping stations.

[0003] The general structural components of a turbofan engine, from front to back, are fan blades, compressor, combustion chamber, turbine, and exhaust nozzle. As aero engines develop towards higher bypass ratios, higher thrust-to-weight ratios, and higher turbine inlet temperatures, the operating temperatures of engine hot-end components are increasing, especially the combustion gas temperature and pressure in the combustion chamber (currently, the combustion temperature in military turbofan engines has reached 2000 degrees Celsius). Components such as turbine disks and turbine blades will be subjected to increasingly severe high-temperature and high-pressure operating environments. Therefore, comprehensive monitoring and timely early warning of engine operation are indispensable technical guarantees for high-performance engines in this era. Real-time detection of the engine's hot-end temperature field allows for timely understanding of the engine's operating status and timely detection of anomalies in the engine body and internal structures, which is a crucial guarantee for ensuring flight safety. To detect temperature changes in critical engine components in real time, there are generally two measurement methods: contact and non-contact. Contact temperature measurement requires full contact with the object being measured to reach thermal equilibrium before obtaining the average temperature of the object and the sensor. Common methods include thermocouples, crystals, and temperature-indicating paint. Non-contact temperature measurement methods, on the other hand, do not require contact with the object being measured to obtain its temperature information. Common methods include fluorescence thermometry, infrared radiation thermometry, and fiber optic thermometry.

[0004] Temperature is one of the crucial parameters that needs to be measured and controlled in industrial production processes. Thermocouples are widely used in temperature measurement due to their advantages, including simple structure, ease of manufacture, wide measurement range, high accuracy, low inertia, and convenient long-distance signal transmission. Furthermore, as a passive sensor, a thermocouple requires no external power supply, making it very convenient to use. Therefore, it is often used to measure the temperature of gases or liquids in furnaces and pipelines, as well as the surface temperature of solids. While thermocouples are widely used, their lifespan is relatively short in corrosive environments, and their calibration process is relatively complex. A thermistor is a sensor resistor whose resistance changes with temperature. Based on their temperature coefficient, they are classified into positive temperature coefficient (PTC) thermistors and negative temperature coefficient (NTC) thermistors. The resistance of a PTC thermistor increases with increasing temperature, while the resistance of a NTC thermistor decreases with increasing temperature; both are semiconductor devices. Thermistors can measure low temperatures, but their temperature resistance is relatively poor. Thermistor materials can generally be classified into three categories: semiconductors, metals, and alloys. Semiconductor thermistor materials include single-crystal semiconductors, polycrystalline semiconductors, glass semiconductors, organic semiconductors, and metal oxides. They all possess very large temperature coefficients of resistance and high resistivity, resulting in highly sensitive sensors. Metal thermistor materials are widely used as resistance temperature sensors, current limiters, and automatic temperature-controlled heating elements. Examples include platinum resistance thermometers, nickel resistance thermometers, and copper resistance thermometers. Platinum temperature sensors, in particular, exhibit significantly high accuracy and stability in various media (including corrosive media). However, the scarcity and high cost of platinum limit their widespread application. Alloy thermistor materials are also known as thermistor alloys. These alloys have high resistivity, and their resistance value is highly sensitive to temperature changes, making them excellent materials for manufacturing temperature sensors.

[0005] Furthermore, existing temperature sensors are only suitable for specific temperature applications and cannot be used for measurements across the entire temperature range, from low to ultra-high temperatures. To meet the demands of high-temperature applications such as aero-engines, there is an urgent need to develop high-sensitivity temperature sensors capable of operating in both high and low temperature environments to satisfy industrial temperature measurement requirements. Summary of the Invention

[0006] To overcome the problems of existing thermocouple temperature measurement technologies, such as short lifespan in corrosive environments and complex calibration processes, and the poor temperature resistance and high cost of thermistor temperature measurement, one of the objectives of this invention is to provide a high-temperature resistant, corrosion-resistant, full-temperature-range ceramic temperature sensor that can meet the needs of various complex working conditions. The specific technical solution is as follows:

[0007] A high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor includes an ultrasonic sensing ceramic rod. One end of the ultrasonic sensing ceramic rod is provided with a crystal orientation induction layer, a piezoelectric functional layer, a protective layer, and a high-temperature resistant electrode layer from the inside to the outside. The piezoelectric functional layer is a columnar AlScCrN coating with (002) orientation.

[0008] Preferably, the (002) oriented columnar AlScCrN coating is a Cr-doped AlScN coating, wherein the Cr content is 1-5 at.%.

[0009] Preferably, the ultrasonic sensing ceramic rod is a surface-polished ultrasonic sensing ceramic rod material with a length of 50-1200 mm, a diameter of 5-10 mm, and a surface roughness of Ra≤0.4 μm.

[0010] Preferably, the ultrasonic sensing ceramic rod is made of alumina, zirconium oxide, or zirconium carbide.

[0011] Preferably, the ultrasonic sensing ceramic rod is a cylinder with a fan-shaped groove on its side surface;

[0012] The bottom length of the fan-shaped groove is 2-5mm, the width of the fan-shaped groove is 0.5-1.0mm, and the distance between the fan-shaped groove and one end of the ceramic rod is 5-100mm.

[0013] Preferably, the crystal orientation induction layer is an AlScCr nanocrystal layer with a (002) orientation, the nanocrystal size is 10-50 nanometers, and the thickness is 100-200 nanometers.

[0014] Preferably, the bonding layer is an AlScCr layer, the protective layer is a sputtered AlScCrO layer, and the high-temperature resistant electrode layer is an AgTa metal alloy layer.

[0015] Preferably, the protective layer has a thickness of 1-10 micrometers and an insulation resistance greater than 100 MΩ;

[0016] The high-temperature resistant electrode layer has a thickness of 1-5 micrometers and a resistance of less than 0.5 ohms.

[0017] The second objective of this invention is to provide a method for preparing the aforementioned high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor. The preparation process is simple, easy to adjust, readily achievable in industrial-scale production, and has high processing efficiency, which can significantly reduce manufacturers' production costs. Specifically, it includes the following steps:

[0018] Step 1: Polish the surface of the ceramic rod and process a fan-shaped groove on its side surface to obtain an ultrasonic sensing ceramic rod.

[0019] Step 2: Ion etching is performed on the surface of the ultrasonic sensing ceramic rod to activate the surface; then a crystallization-inducing layer is deposited.

[0020] Step 3: After the crystallization-induced layer deposition is completed, a piezoelectric functional coating is deposited.

[0021] Step 4: After the piezoelectric functional layer is deposited, a protective layer is prepared using radio frequency sputtering.

[0022] Step 5: After the protective layer is prepared, a high-temperature resistant electrode layer is deposited using a sputtering method to obtain a high-temperature resistant, corrosion-resistant, full-temperature-range measurement ceramic temperature sensor.

[0023] The high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor prepared by the above method has a high piezoelectric constant, which allows the sensor to work in high-temperature environments and meet the application requirements under different temperature conditions. At the same time, its industrial production is easy to achieve and the processing efficiency is high, which can significantly reduce the production cost of manufacturers.

[0024] Preferably, the preparation method of the above-mentioned high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor includes the following steps:

[0025] Step 1: Polish the surface of the ceramic rod and process a fan-shaped groove on its side surface to obtain an ultrasonic sensing ceramic rod.

[0026] Step 2: Ion etching is performed on the surface of the ultrasonic sensing ceramic rod to activate the surface; then, under the conditions of 100-500℃ and 0.5-4.0Pa, a 50-200 nm (002) oriented AlScCr crystallization-inducing layer is deposited with a nanocrystal size of 10-50 nm.

[0027] Step 3: After the AlScCr crystallization-induced layer is deposited, a (002) oriented AlScCrN piezoelectric functional coating is deposited under conditions of 0.5-4.0 Pa and 0-50 V.

[0028] Step 4: After the piezoelectric functional layer is deposited, a protective layer is prepared by radio frequency sputtering under conditions of 1-4 Pa and 0-100 V.

[0029] Step 5: After the protective layer is prepared, a high-temperature resistant electrode layer is deposited by sputtering at 100-500℃ and 0.5-5.0Pa to obtain a high-temperature resistant and corrosion-resistant full-temperature range ceramic temperature sensor.

[0030] Beneficial effects:

[0031] The beneficial effects of adopting the technical solution of this invention are as follows:

[0032] (1) For the first time, ceramic materials were used as temperature sensors for temperature detection, avoiding the disadvantages of traditional thermocouples, such as slow response speed and inability to work in corrosive environments.

[0033] (2) Temperature changes are measured by using the change in ultrasonic running time. The response speed is fast, at the nanosecond level, so it can respond to even very small temperature changes.

[0034] (3) The ceramic temperature sensor used can operate from a low temperature of liquid nitrogen to a high temperature of 2500℃, achieving temperature measurement over a wide temperature range for the first time.

[0035] (4) Make full use of the characteristics of the fan-shaped groove to reflect ultrasound to improve the accuracy of temperature detection and avoid errors caused by uneven spatial distribution of temperature in the ultrasonic transmission ceramic rod;

[0036] (5) Traditional AlN materials have insufficient corrosion resistance and cannot withstand high-temperature oxidation corrosion. Compared with conventional single-layer AlN piezoelectric coating materials, AlScCrN piezoelectric thin films are formed by doping AlScN with Cr to improve piezoelectric performance. After adding Cr to AlScN materials, their corrosion resistance and wear resistance are improved.

[0037] (6) A multi-layer structure consisting of a crystal orientation induction layer, a piezoelectric functional layer, a protective layer, and a high-temperature resistant electrode layer is adopted to stack materials such as AlScCr, AlScCrN, and AlScCrO to form a low-stress ultrasonic sensor, which improves the bonding strength between the coating material and the ceramic rod.

[0038] (7) The AlScCrO coating is prepared on the surface of the piezoelectric composite coating by radio frequency sputtering, which can effectively protect the piezoelectric composite coating from oxidation by air at high temperature;

[0039] (8) AgTa is prepared on the surface of the protective layer to form a conductive layer, which has the characteristics of high conductivity, high temperature resistance and high wear resistance;

[0040] (9) Combining radio frequency sputtering technology with the preparation of ultrasonic sensor coating materials not only results in a fast deposition rate, but also better crystallization and bonding performance, which will greatly improve the adaptability of piezoelectric coating materials on various materials and expand their application fields. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0042] Figure 1 is a schematic diagram of the ceramic temperature sensor structure in this invention;

[0043] Figure 2 is a schematic diagram of the coating structure of the ceramic temperature sensor in this invention;

[0044] Figure 3 is a flowchart of the fabrication process of the ceramic temperature sensor in this invention;

[0045] Figure 4 is a schematic diagram of the coating device in the fabrication process of the ceramic temperature sensor in this invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0047] The ceramic temperature sensor used in this embodiment can operate from a low temperature of liquid nitrogen to a high temperature of 2500°C, achieving temperature measurement over a wide temperature range for the first time. The specific implementation method is as follows:

[0048] As shown in Figures 1 and 2, a high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor includes an ultrasonic sensing ceramic rod 1. One end of the ultrasonic sensing ceramic rod 1 has a coating structure 11. The coating structure 11, from the inside out, consists of a crystal orientation induction layer 2, a piezoelectric functional layer 3, a protective layer 4, and a high-temperature resistant electrode layer 5. The piezoelectric functional layer 3 is a (002) oriented columnar AlScCrN coating. As can be seen from the figures, the coating structure exhibits a compositional and hardness gradient, reducing the stress of the coating and allowing for the deposition of a thicker piezoelectric coating.

[0049] In a preferred embodiment, the (002) oriented columnar AlScCrN coating is a Cr-doped AlScN coating, wherein the Cr content is 1-5 at.%.

[0050] In a preferred embodiment, the ultrasonic sensing ceramic rod 1 is a surface-polished ultrasonic sensing ceramic rod material with a length of 50-1200 mm, a diameter of 5-10 mm, and a surface roughness of Ra≤0.4 μm.

[0051] In a preferred embodiment, the ultrasonic sensing ceramic rod 1 is made of alumina, zirconium oxide, or zirconium carbide.

[0052] In a preferred embodiment, the ultrasonic sensing ceramic rod 1 is a cylinder with a fan-shaped groove 6 on its side surface; here, the central axis of the fan-shaped groove 6 coincides with the central axis of the ultrasonic sensing ceramic rod.

[0053] The bottom length of the fan-shaped groove is 2-5mm, the width of the fan-shaped groove is 0.5-1mm, and the distance between the fan-shaped groove and one end of the ceramic rod is 5-100mm.

[0054] In a preferred embodiment, the crystal orientation induction layer is an AlScCr nanocrystal layer with a (002) orientation, the nanocrystal size being 10-50 nanometers and the thickness being 100-200 nanometers.

[0055] In a preferred embodiment, the bonding layer is an AlScCr layer, the protective layer is a sputtered AlScCrO layer, and the high-temperature resistant electrode layer is an AgTa metal alloy layer.

[0056] In a preferred embodiment, the protective layer has a thickness of 1-10 micrometers and an insulation resistance greater than 100 MΩ;

[0057] The high-temperature resistant electrode layer has a thickness of 1-5 micrometers and a resistance of less than 0.5 ohms.

[0058] The second objective of this embodiment is to provide a method for fabricating the aforementioned high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor. The fabrication process is simple, easy to adjust, readily achievable in industrial-scale production, and has high processing efficiency, significantly reducing manufacturers' production costs. As shown in Figure 3, the specific steps include:

[0059] Step S101: Polish the surface of the ceramic rod and process a fan-shaped groove on its side surface to obtain an ultrasonic sensing ceramic rod.

[0060] Step S102: Ion etching is performed on the surface of the ultrasonic sensing ceramic rod to activate the surface; then a crystallization-inducing layer is deposited.

[0061] Step S103: After the crystallization-induced layer deposition is completed, a piezoelectric functional coating is deposited.

[0062] Step S104: After the piezoelectric functional layer is deposited, a protective layer is prepared by radio frequency sputtering.

[0063] Step S105: After the protective layer is prepared, a high-temperature resistant electrode layer is deposited by sputtering to obtain a high-temperature resistant and corrosion-resistant full-temperature range measurement ceramic temperature sensor.

[0064] As shown in Figure 3, a fan-shaped ultrasonic reflection groove is first processed on a ceramic rod; then, a piezoelectric sensor is fabricated. The fan-shaped groove primarily reflects ultrasonic waves. A relationship is established between the time difference Δt (the time t2 for the ultrasound to travel from the sensor to the other end of the rod and the time t1 for the groove) and the temperature T. The temperature change is then measured by measuring Δt.

[0065] As shown in Figure 4, the vacuum chamber of the coating apparatus for preparing the ceramic temperature sensor is enclosed by the furnace wall 100. The vacuum chamber has an extraction port 40, through which a vacuum pump unit evacuates the chamber. Heaters 30 are located at the four corners of the vacuum chamber. Three targets are mounted in three rows on the furnace wall 100: one chromium etching target 10 and two AlScCr coating targets 20. The sample 50 is mounted on a workpiece holder. This layout significantly increases the plasma density in the vacuum chamber, completely immersing the workpiece in the plasma, thus greatly improving the coating deposition rate, hardness, and adhesion. Due to the optimized target structure, the magnetic field distribution is more uniform, resulting in more uniform etching of the magnetron sputtering target surface and improved coating uniformity.

[0066] The high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor prepared by the above method has a high piezoelectric constant, which allows the sensor to work in high-temperature environments and meet the application requirements under different temperature conditions. At the same time, its industrial production is easy to achieve and the processing efficiency is high, which can significantly reduce the production cost of manufacturers.

[0067] Preferably, the preparation method of the above-mentioned high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor includes the following steps:

[0068] Step S101: Polish the surface of the ceramic rod and process a fan-shaped groove on its side surface to obtain an ultrasonic sensing ceramic rod.

[0069] Step S102: Ion etching is performed on the surface of the ultrasonic sensing ceramic rod to activate the surface; then, under the conditions of 100-500℃ and 0.5-4Pa, a 50-200 nm (002) oriented AlScCr crystallization induction layer is deposited, with a nanocrystal size of 10-50 nm.

[0070] Step S103: After the AlScCr crystallization-induced layer is deposited, a (002) oriented AlScCrN piezoelectric functional coating is deposited under conditions of 0.5-4 Pa and 0-50 V.

[0071] Step S104: After the piezoelectric functional layer is deposited, a protective layer is prepared by radio frequency sputtering under conditions of 1-4 Pa and 0-100 V.

[0072] In step S105, after the protective layer is prepared, a high-temperature resistant electrode layer is deposited by sputtering at 100-500℃ and 0.5-5Pa to obtain a high-temperature resistant and corrosion-resistant full-temperature range ceramic temperature sensor.

[0073] The following five examples further illustrate the beneficial effects of the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor and its preparation method in this invention.

[0074] Example 1

[0075] The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor in this embodiment includes the following steps:

[0076] Step 1: Polish the surface of a ceramic rod with a length of 50 mm and a diameter of 5 mm. The surface roughness after polishing is 0.1 μm. The ceramic rod material is alumina. A fan-shaped defect is processed at a certain position on the ceramic rod. The length of the bottom surface of the defect is 2 mm, the width of the fan-shaped defect is 0.5 mm, and the distance between the fan-shaped defect and the end of the ceramic rod is 5 mm.

[0077] Step 2: First, the ceramic rod is ion-etched to activate the surface. Then, a 50-nanometer (002) oriented AlScCr crystallization-inducing layer is deposited at 100℃ and 0.5Pa, with a nanocrystal size of 10 nanometers.

[0078] Step 3: After the AlScCr crystallization-induced layer is deposited, an AlScCrN piezoelectric functional coating with (002) orientation is deposited under the conditions of 0.5 Pa and 0 V. The AlScCrN piezoelectric material is a Cr-doped AlScN coating with a Cr content of 1 at.%.

[0079] Step 4: After the piezoelectric functional layer is deposited, an AlScCrO protective layer is deposited under 1 Pa and 0 V conditions. The protective layer is prepared by radio frequency sputtering and has a thickness of 1 micrometer and an insulation resistance greater than 100 MΩ.

[0080] Step 5: After the AlScCrO protective layer is prepared, a 1-micron AgTa alloy layer is deposited at 100℃ and 0.5 Pa, with a resistance of less than 0.5 ohms.

[0081] After preparation, a corrosion-resistant and high-temperature resistant ceramic temperature sensor was obtained.

[0082] Example 2

[0083] The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor in this embodiment includes the following steps:

[0084] Step 1: Polish the surface of a ceramic rod with a length of 50 mm and a diameter of 5 mm. The surface roughness after polishing is 0.1 μm. The ceramic rod material is zirconia. A fan-shaped defect is processed at a certain position on the ceramic rod. The length of the bottom surface of the defect is 5 mm, the width of the fan-shaped defect is 1 mm, and the distance between the fan-shaped defect and the end of the ceramic rod is 100 mm.

[0085] Step 2: First, the ceramic rod is ion-etched to activate the surface. Then, a 200 nm (002) oriented AlScCr crystallization-inducing layer is deposited at 500 °C and 4 Pa, with a nanocrystal size of 50 nm.

[0086] Step 3: After the AlScCr crystallization-induced layer is deposited, an AlScCrN piezoelectric functional coating with (002) orientation is deposited under the conditions of 4 Pa ​​and 50 V. The AlScCrN piezoelectric material is a Cr-doped AlScN coating with a Cr content of 5 at.%.

[0087] Step 4: After the piezoelectric functional layer is deposited, an AlScCrO protective layer is deposited under conditions of 4 Pa ​​and 100 V. The protective layer is prepared by radio frequency sputtering and has a thickness of 10 micrometers and an insulation resistance greater than 100 MΩ.

[0088] Step 5: After the AlScCrO protective layer is prepared, a 5-micron AgTa alloy layer is deposited at 500℃ and 5 Pa, with a resistance of less than 0.5 ohms.

[0089] After preparation, a corrosion-resistant and high-temperature resistant ceramic temperature sensor was obtained.

[0090] Example 3

[0091] The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor in this embodiment includes the following steps:

[0092] Step 1: Polish the surface of a ceramic rod with a length of 1000 mm and a diameter of 8 mm. The surface roughness after polishing is 0.3 μm. The ceramic rod material is zirconia. A fan-shaped defect is processed at a certain position on the ceramic rod. The length of the bottom surface of the defect is 3 mm, the width of the fan-shaped defect is 0.6 mm, and the distance between the fan-shaped defect and the end of the ceramic rod is 50 mm.

[0093] Step 2: First, the ceramic rod is ion-etched to activate the surface. Then, a 100-nanometer (002) oriented AlScCr crystallization-inducing layer with a nanocrystal size of 30 nanometers is deposited at 300℃ and 2Pa.

[0094] Step 3: After the AlScCr crystallization-induced layer is deposited, an AlScCrN piezoelectric functional coating with (002) orientation is deposited under the conditions of 3 Pa and 40 V. The AlScCrN piezoelectric material is a Cr-doped AlScN coating with a Cr content of 5 at.%.

[0095] Step 4: After the piezoelectric functional layer is deposited, an AlScCrO protective layer is deposited under 2Pa and 50V conditions. The protective layer is prepared by radio frequency sputtering and has a thickness of 5 micrometers and an insulation resistance greater than 100MΩ.

[0096] Step 5: After the AlScCrO protective layer is prepared, a 3-micron AgTa alloy layer is deposited at 400℃ and 3Pa, with a resistance of less than 0.5 ohms.

[0097] After preparation, a corrosion-resistant and high-temperature resistant ceramic temperature sensor was obtained.

[0098] Example 4

[0099] The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor in this embodiment includes the following steps:

[0100] Step 1: Polish the surface of a ceramic rod with a length of 1000mm and a diameter of 80mm. The surface roughness after polishing is 0.1μm. The ceramic rod material is zirconium carbide. A fan-shaped defect is processed at a certain position on the ceramic rod. The length of the bottom surface of the defect is 3mm, the width of the fan-shaped defect is 0.8mm, and the distance between the fan-shaped defect and the end of the ceramic rod is 50mm.

[0101] Step 2: First, the ceramic rod is ion-etched to activate the surface. Then, a 100-nanometer (002) oriented AlScCr crystallization-inducing layer with a nanocrystal size of 40 nanometers is deposited at 500℃ and 0.5Pa.

[0102] Step 3: After the AlScCr crystallization-induced layer is deposited, an AlScCrN piezoelectric functional coating with (002) orientation is deposited under the conditions of 0.5 Pa and 50 V. The AlScCrN piezoelectric material is a Cr-doped AlScN coating with a Cr content of 4 at.%.

[0103] Step 4: After the piezoelectric functional layer is deposited, an AlScCrO protective layer is deposited under 1 Pa and 80 V conditions. The protective layer is prepared by radio frequency sputtering and has a thickness of 8 micrometers and an insulation resistance greater than 100 MΩ.

[0104] Step 5: After the AlScCrO protective layer is prepared, a 3-micron AgTa alloy layer is deposited at 300℃ and 2Pa, with a resistance of less than 0.5 ohms.

[0105] After preparation, a corrosion-resistant and high-temperature resistant ceramic temperature sensor was obtained.

[0106] Example 5

[0107] The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor in this embodiment includes the following steps:

[0108] Step 1: Polish the surface of a ceramic rod with a length of 800 mm and a diameter of 7 mm. The surface roughness after polishing is 0.3 μm. The ceramic rod material is alumina. A fan-shaped defect is processed at a certain position on the ceramic rod. The length of the bottom surface of the defect is 4 mm, the width of the fan-shaped defect is 0.7 mm, and the distance between the fan-shaped defect and the end of the ceramic rod is 70 mm.

[0109] Step 2: First, perform ion etching on the ceramic rod to activate the surface. Then, deposit a 100-nanometer (002)-oriented AlScCr crystallization induction layer at 200 °C and 3 Pa, with a nanocrystal scale of 40 nanometers.

[0110] Step 3: After the deposition of the AlScCr crystallization induction layer, deposit a (002)-oriented AlScCrN piezoelectric functional coating at 2 Pa and 20 V. The AlScCrN piezoelectric material is a Cr-doped AlScN coating with a Cr content of 2 at.%.

[0111] Step 4: After the deposition of the piezoelectric functional layer, deposit an AlScCrO protective layer at 3 Pa and 30 V. It is prepared by radio frequency sputtering method, with a protective layer thickness of 3 microns and an insulation resistance greater than 100 MΩ.

[0112] Step 5: After the preparation of the AlScCrO protective layer, deposit a 3-micron AgTa alloy layer at 300 °C and 4 Pa, with a resistance lower than 0.5 ohms.

[0113] After the preparation, a corrosion-resistant and high-temperature-resistant ceramic temperature sensor is obtained.

[0114] After testing, the temperature sensors obtained in Examples 1-5 can operate from the low temperature of liquid nitrogen temperature to the high temperature of 2500 °C, and have a fast response speed, with the response speed at the nanosecond level. Next, perform high and low temperature cycle tests and piezoelectric properties on the temperature sensors obtained in the above five groups of examples.

[0115] For the high and low temperature cycle test, the low temperature test is that the fastener is placed in an environment of -30 °C for 96 h and the recovery time at normal temperature is 2 h; the high temperature test is that the fastener is placed in an environment of +80 °C for 96 h and the recovery time at normal temperature is 2 h; for the high temperature and high humidity cycle test, the fastener is placed in an environment of +60 °C and 95% RH for 96 h and the recovery time at normal temperature is 2 h; for the temperature shock, -30 °C / +80 °C, 10 cycles of 1 h / 1 h, and the conversion time is less than 3 min. After the climate performance test, the adhesion of the fastener thin film device layer needs to be detected, and it is qualified when no peeling of the thin film coating is detected.

[0116] Table 1 Test results of temperature sensors in each group of examples

[0117] Item High and low temperature cycle test performance Piezoelectric performance Response speed Example 1 No peeling on the surface, qualified D33 = 158 microseconds Example 2 No peeling on the surface, qualified D33 = 189 microseconds Example 3 No peeling on the surface, qualified D33 = 2011 microseconds Example 4 No peeling on the surface, qualified D33 = 1610 microseconds Example 5 No peeling on the surface, qualified D33 = 229 microseconds Table

[0118] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor, characterized in that, The device includes an ultrasonic sensing ceramic rod, wherein one end of the ultrasonic sensing ceramic rod is sequentially provided with a crystal orientation induction layer, a piezoelectric functional layer, a protective layer, and a high-temperature resistant electrode layer from the inside to the outside. The piezoelectric functional layer is a (002) oriented columnar AlScCrN coating. The ultrasonic sensing ceramic rod is a cylinder with a fan-shaped groove on its side surface. The bottom length of the fan-shaped groove is 2-5 mm, the width of the fan-shaped groove is 0.5-1.0 mm, and the distance between the fan-shaped groove and the end of one end of the ceramic rod is 5-100 mm. The crystal orientation induction layer is a (002) oriented AlScCr nanocrystalline layer with a nanocrystal size of 10-50 nm and a thickness of 100-200 nm. The protective layer is a sputtered AlScCrO layer, and the high-temperature resistant electrode layer is an AgTa metal alloy layer.

2. The high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor according to claim 1, characterized in that, The (002) oriented columnar AlScCrN coating is a Cr-doped AlScN coating, wherein the Cr content is 1-5 at.

3. The high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor according to claim 1, characterized in that, The ultrasonic sensing ceramic rod is a surface-polished ultrasonic sensing ceramic rod material with a length of 50-1200 mm, a diameter of 5-10 mm, and a surface roughness of Ra≤0.4 μm.

4. The high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor according to claim 3, characterized in that, The ultrasonic sensing ceramic rod is made of alumina, zirconium oxide, or zirconium carbide.

5. The high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor according to claim 1, characterized in that, The protective layer has a thickness of 1-10 micrometers and an insulation resistance greater than 100MΩ; the high-temperature resistant electrode layer has a thickness of 1-5 micrometers and a resistance less than 0.5 ohms.

6. The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor as described in any one of claims 1-5, characterized in that, The process includes the following steps: Step 1, polishing the surface of the ceramic rod and machining a fan-shaped groove on its side surface to obtain an ultrasonic sensing ceramic rod; Step 2, ion etching the surface of the ultrasonic sensing ceramic rod to activate the surface; then depositing a crystallization-inducing layer; Step 3, after the crystallization-inducing layer is deposited, depositing a piezoelectric functional coating; Step 4, after the piezoelectric functional layer is deposited, preparing a protective layer using radio frequency sputtering; Step 5, after the protective layer is prepared, depositing a high-temperature resistant electrode layer using sputtering to obtain a high-temperature resistant, corrosion-resistant, full-temperature-range measurement ceramic temperature sensor.

7. The method for preparing the high-temperature resistant and corrosion-resistant full-temperature-range ceramic temperature sensor according to claim 6, characterized in that, The process includes the following steps: Step 1, polishing the surface of the ceramic rod and machining a fan-shaped groove on its side surface to obtain an ultrasonic sensing ceramic rod; Step 2, ion etching the surface of the ultrasonic sensing ceramic rod to activate the surface; then, at 100-500℃ and 0.5-4Pa, depositing a 50-200 nm (002) oriented AlScCr crystallization-inducing layer with a nanocrystal size of 10-50 nm; Step 3, after the AlScCr crystallization-inducing layer is deposited, a (002) oriented AlScCrN piezoelectric functional coating is deposited at 0.5-4.0Pa and 0-50V; Step 4, after the piezoelectric functional layer is deposited, a protective layer is prepared by radio frequency sputtering at 1-4Pa and 0-100V; Step 5, after the protective layer is prepared, a high-temperature resistant electrode layer is deposited by sputtering at 100-500℃ and 0.5-5.0Pa to obtain a high-temperature resistant and corrosion-resistant full-temperature-range measurement ceramic temperature sensor.

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