Pressure-resistant steel-based nano-film pressure sensor and application thereof

Abstract

The invention discloses a pressure-resistant steel-based nano-film pressure sensor and application thereof, and belongs to the technical field of pressure sensors, and the pressure-resistant steel-based nano-film pressure sensor comprises a pressure core body which is fixedly connected with a lower ceramic insulating plate through a glass micro-melting layer; the pressure guide nozzle and the steel-based connecting piece are melted through the glass micro-melting layer to form a closed structure; the protective layer comprises a glaze layer which is coated on the annular outer surface of a combined piece formed by combining the steel-based connecting piece and the ceramic insulating plate; and the epoxy glue layer covers the exposed end surface of the glass micro-melting layer to form a closed space. The pressure-resistant steel-based nano-film pressure sensor prepared by the invention is relatively high in insulating strength and precision, and can be applied to petroleum and natural gas, aerospace, military industry, industrial automation and medical and special equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressure sensors, and particularly relates to a pressure-resistant steel-based nano-film pressure sensor and its application. Background Art

[0002] Pressure sensors are widely used in fields such as industrial automation, aerospace, and energy extraction to measure the pressure changes of gases or liquids. High-pressure sensors still have the following problems in terms of long-term stability and environmental adaptability: Insufficient sealing reliability: Traditional glass sintering or adhesive sealing is prone to generating micro-cracks under high-pressure cycles, resulting in medium penetration or insulation failure; Stress concentration in the connection structure: When connecting metal-ceramic heterogeneous materials, interface peeling is prone to occur under temperature shock; Insufficient environmental protection: In corrosive environments such as the ocean and chemical industries, metal components of sensors are easily eroded by media such as, resulting in shortened service life.

[0003] The insulation withstand voltage of existing steel-based film pressure sensors generally ranges between 300 and 500 VAC. The principle of the steel-based film pressure core is to coat a film on the surface of the steel base. Currently, most of the used coating schemes are CVD chemical deposition technology. This technology has defects. To achieve high withstand voltage, the insulation layer must be thickened, but thickening the insulation layer will lead to contradictions such as insulation layer cracking and deterioration of the sensor's accuracy performance. Summary of the Invention

[0004] To overcome the above technical problems, the present invention provides a pressure-resistant steel-based nano-film pressure sensor and its application. The pressure-resistant steel-based nano-film pressure sensor prepared by the present invention has relatively high insulation strength and accuracy.

[0005] The present invention solves the above technical problems through the following technical solutions.

[0006] A pressure-resistant steel-based nano-film pressure sensor, comprising: A pressure inlet nozzle, one side of which is connected to a ceramic insulating plate; One side of the ceramic insulating plate is provided with a steel-based connector; One side of the steel-based connector is provided with a steel-based pressure core; The pressure inlet nozzle, the ceramic insulating plate, and the steel-based connector are connected through a glass micro-melting layer; An epoxy adhesive layer is provided on one side of the glass micro-melting layer.

[0007] In the present invention, the steel base is a conventional steel base in the art, and its material is a conventional stainless steel material in the art. In the present invention, 17-4PH stainless steel is used for the steel base.

[0008] In the present invention, the steel-based connector is fixedly connected to the outer peripheral shell of the lower part of the pressure core.

[0009] In the present invention, the steel-based connector is connected through a glass micro-melting layer and a pressure guiding nozzle; the steel-based connector is connected through a glass micro-melting layer and a ceramic insulating plate.

[0010] In the present invention, the pressure core is composed of a steel base and a nano-film layer on its surface; the nano-film sequentially includes a transition layer, an insulating layer, a nickel-chromium alloy layer, a pad layer, and a protective layer from bottom to top.

[0011] In the present invention, the composition of the transition layer is Al-doped ZrO2 and Al-doped TiN. The thermal expansion coefficient of the transition layer can bridge the difference between the steel base and the insulating layer, reducing stress; and it realizes atomic-level stacking by atomic deposition method, blocking the penetration path of high-pressure media.

[0012] In the present invention, by mass fraction, the composition of the insulating layer is 60-70% Y-doped Si3N4 and 30-40% Y-doped AlN. In the insulating layer, Y-doped AlN has heat conduction performance, and Y-doped Si3N4 has good corrosion resistance and insulation performance; compared with the traditional silica insulating layer, the insulating layer in the present invention has high-temperature stability, the doped Y disperses stress concentration, and the overall mechanical strength of the insulating layer is high.

[0013] In the present invention, the composition of the nickel-chromium alloy layer is Ni 70~80 Cr 20~30 .

[0014] In the present invention, the composition of the pad layer is Au.

[0015] In the present invention, the composition of the protective layer is SiCB. This composite phase has high hardness, good insulation and anti-friction performance, and the doping of B element can promote adhesion.

[0016] In the present invention, the preparation method of the transition layer: adopting an atomic deposition process, at 250-300 °C, first deposit Ti source and Al source at a deposition rate of 0.08-0.12 nm / cycle for 10-15 min, and then use Zr source and Al source to deposit at a deposition rate of 0.08-0.12 nm / cycle for 10-15 min.

[0017] In the present invention, the preparation method of the insulating layer: adopting an atomic deposition process using Si source, Al source and Y source as precursors, NH3 and N2 as reaction gases, the deposition temperature is 600-800 °C, and the deposition time is 16-20 h.

[0018] In the present invention, the preparation method of the protective layer: Plasma Enhanced Chemical Vapor Deposition is adopted, using SiH4, CH4, and B2H6 as precursor gases, with a radio frequency power of 300 - 400 W, a deposition temperature of 200 - 300 °C, a deposition pressure of 80 - 150 Pa, and a deposition time of 0.8 - 1.5 h.

[0019] In the present invention, the thickness of the transition layer is 40 - 60 nm.

[0020] In the present invention, the thickness of the insulating layer is 3 - 7 μm.

[0021] In the present invention, the thickness of the nickel - chromium alloy layer is 60 - 90 nm.

[0022] In the present invention, the thickness of the pad layer is 0.8 - 1.5 μm.

[0023] In the present invention, the thickness of the protective layer is 1 - 2 μm.

[0024] In the present invention, the thickness of the glass micro - melting layer is 1 - 3 mm.

[0025] In the present invention, by mass fraction, the composition of the glass powder used in the glass micro - melting layer is 10 - 20% B2O3, 8 - 13% Na2O, 3 - 9% Al2O3, and the balance SiO2.

[0026] In the present invention, the glass micro - melting process of the glass micro - melting layer is to heat the glass powder in a vacuum environment at a rate of 5 - 10 °C / min to 870 - 890 °C, hold for 20 - 30 min, and then cool to 300 - 350 °C and apply a pressure of 0.5 - 1 MPa for compaction.

[0027] In the present invention, the epoxy adhesive layer is provided on the upper surface of the glass micro - melting layer.

[0028] In the present invention, the shear strength of the epoxy adhesive used in the epoxy adhesive layer is ≥25 MPa, preferably 25 - 30 MPa; In the present invention, the surface resistivity of the epoxy adhesive used in the epoxy adhesive layer is ≥2.8×10 16 Ω, preferably 2.8×10 16 ~3.0×10 16 Ω.

[0029] In the present invention, a glaze layer is further provided on the lower surface of the glass micro - melting layer, and the glaze layer is located between the glass micro - melting layer and the ceramic insulating plate.

[0030] In the present invention, by mass fraction, the composition of the glaze used in the glaze layer includes 22 - 28% Al2O3, 10 - 15% B2O3, 5 - 9% ZnO, 1 - 4% Ta2O5, 2 - 5% CeO2, and the balance SiO2.

[0031] In the present invention, the thickness of the ceramic insulating plate is 1-5 mm, preferably 2-3 mm.

[0032] In the present invention, the alumina content in the ceramic insulating plate is ≥95%.

[0033] The present invention also discloses the application of the above-mentioned high-voltage-resistant steel-based nano-film pressure sensor in the field of test pressure, such as its application in oil and gas, aerospace, military, industrial automation, and medical and special equipment.

[0034] On the basis of conforming to the common knowledge in the art, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred examples of the present invention.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention adopts a multi-layer sealing technology to improve the sealing level. The glass micro-melting layer conducts basic sealing, the glaze layer covers the joint of the steel-based connector and the ceramic insulating plate to block the water vapor penetration path, and the epoxy glue coats the surface of the glass micro-melting layer to form a molecular-level density.

[0036] 2. In the nano-film layer of the present invention, the transition layer improves the bonding property of two heterogeneous materials, namely the steel base and the insulating layer. The protective layer has good high-voltage resistance and sealing performance. The optimization of the nano-film layer enables the pressure core to have high-voltage resistance performance, and it still has high precision and performance after a 1000 VAC insulation voltage withstand test. Description of the Drawings

[0037] Figure 1 It is a schematic diagram of a high-voltage-resistant steel-based nano-film pressure sensor.

[0038] Figure 2 It is a schematic diagram of the pressure core.

[0039] Figure 3 It is a schematic diagram of the nano-film layer.

[0040] Figure 4 It is a partial schematic diagram of the high-voltage-resistant steel-based nano-film pressure sensor (protective layer).

[0041] Reference numerals: 1, pressure core; 11, steel base; 12, nano-film layer; 121, transition layer; 122, insulating layer; 123, nickel-chromium alloy layer; 124, pad layer; 125, protective layer; 2, steel-based connector; 3, glass micro-melting layer; 31, glaze layer; 32, epoxy glue layer; 4, ceramic insulating plate; 5, pressure inlet nozzle; 6, adapter plate; 7, adapter plate bracket; 8, gold wire; 9, output interface. Detailed Embodiments

[0042] To facilitate the understanding of the present invention, the following will describe the present invention more comprehensively and meticulously in conjunction with preferred embodiments. However, the protection scope of the present invention is not limited to the following specific embodiments.

[0043] Unless otherwise defined, all the technical terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present invention. The "range" disclosed in the present invention is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a specific range. The range defined in this way can include the end values or not include the end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 - 120 and 80 - 110 are listed for a specific parameter, ranges of 60 - 110 and 80 - 120 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all contemplated: 1 - 3, 1 - 4, 1 - 5, 2 - 3, 2 - 4, and 2 - 5. In the present invention, unless otherwise specified, the numerical range "a - b" represents an abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0 - 5" means that all real numbers between "0 - 5" have been fully listed herein, and "0 - 5" is only an abbreviated representation of these numerical combinations. Additionally, when stating that a certain parameter is an integer ≥2, it is equivalent to disclosing that the parameter is, for example, the integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0044] If there is no special indication, all the embodiments of the present invention and the optional embodiments can be combined with each other to form a new technical solution.

[0045] If there is no special indication, all the technical features of the present invention and the optional technical features can be combined with each other to form a new technical solution.

[0046] If there is no special indication, all the steps of the present invention can be carried out in sequence or randomly, preferably in sequence. For example, the method includes steps (a) and (b), which means that the method can include steps (a) and (b) carried out in sequence, or can also include steps (b) and (a) carried out in sequence. For example, it is mentioned that the method may further include step (c), which means that step (c) can be added to the method in any order. For example, the method can include steps (a), (b), and (c), or can also include steps (a), (c), and (b), or can also include steps (c), (a), and (b), etc.

[0047] Unless otherwise specified, the terms "comprising" and "including" mentioned in the present invention mean open-ended, and can also be closed-ended. For example, the terms "comprising" and "including" can mean that other components not listed can also be included or contained, or can only include or contain the listed components.

[0048] Unless otherwise specified, in the present invention, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) while B is true (or exists); or both A and B are true (or exist).

[0049]

Structure of the pressure-resistant steel-based nano-film pressure sensor

[0050] For the pressure-resistant steel-based nano-film pressure sensor with the above structure, the materials and related preparation processes involved are as follows:

Materials and related preparation processes of the pressure-resistant steel-based nano-film pressure sensor

[0051] Example 1 1. Nano-film layer Intermediate layer : The thickness is 50 nm, and its components are Al-doped ZrO2 and Al-doped TiN; Preparation process of the transition layer: Using atomic deposition process, first deposit Ti source and Al source at a deposition rate of 0.12 nm / cycle at 280 °C with nitrogen and ammonia as carrier gases for 15 min; then deposit Zr source, Al source at a deposition rate of 0.12 nm / cycle with nitrogen and oxygen as carrier gases for 15 min; deposit Al-doped TiN and Al-doped ZrO2 in sequence; Among them, the Zr source is ZrCl4, the Ti source is TiCl4, and the Al source is Al(CH3)3; Insulating layer : with a thickness of 5 μm, and its composition is 67% Y-doped Si3N4 and 33% Y-doped AlN; Preparation method of the insulating layer: Using atomic deposition process, using Si source, Al source and Y source as precursors, nitrogen and ammonia as carrier gases, deposition temperature is 700 °C, deposition time is 18 h; Among them, the silicon source is SiH2Cl2, the aluminum source is Al(CH3)3, and the Y source is Y(thd)3 (CAS No.: 15632-39-0).

[0052] Nickel-chromium alloy layer : with a thickness of 60 nm, and its composition is Ni 75 Cr 25 ; Pad layer : with a thickness of 0.8 μm, and its composition is Au; Protective layer : with a thickness of 1.5 μm, and its composition is SiCB; Preparation method of the protective layer: Using plasma-enhanced chemical vapor deposition, with SiH4, CH4, Ar, B2H6 in a volume ratio of 10:5:50:1, total gas flow rate of 66 sccm, radio frequency power of 350 W, deposition temperature of 250 °C, deposition pressure of 100 Pa, deposition time of 1.5 h.

[0053] 2. Glass micro-melting layer The thickness of the glass micro-melting layer is 2.5 mm; The composition of the glass powder used in the glass micro-melting layer is 15% B2O3, 10% Na2O, 5% Al2O3, and the balance is SiO2; The glass micro-melting process of the glass micro-melting layer is to heat the glass powder to 890 °C at a rate of 10 °C / min in a vacuum environment, hold for 20 min, and then cool to 320 °C and apply a pressure of 0.5 MPa for compaction.

[0054] 3. Ceramic insulating board The thickness of the ceramic insulating board is 2.5 mm, and the ceramic insulating board contains 97 wt% alumina.

[0055] 4. The epoxy adhesive used in the epoxy adhesive layer is purchased from Jinshineng Technology Co., Ltd. in Zhuhai, Jinshida K-3815. The main component of this epoxy adhesive is epoxy resin, with a shear strength of 25 MPa, an elongation at break of 3.5%, and a surface resistance of 2.8×10 16 Ω.

[0056] 5. Glaze layer The composition of the glaze used in the glaze layer is 22% Al2O3, 12% B2O3, 8% ZnO, 3% Ta2O5, 3% CeO2, and the balance SiO2; Preparation method of the glaze layer: After coating the glaze, sinter it at 810 °C for 1 h.

[0057] Example 2 The difference between this example and Example 1 is: Transition layer: with a thickness of 42 nm, and its composition is Al-doped ZrO2 and Al-doped TiN; Preparation process of the transition layer: Adopt the atomic deposition process. At 290 °C, first deposit the Ti source and Al source at a deposition rate of 0.10 nm / cycle for 12 min, and then use the Zr source and Al source to deposit at a deposition rate of 0.10 nm / cycle for 10 min.

[0058] Other structures, parameters, and preparation processes are the same as those in Example 1.

[0059] Example 3 The difference between this example and Example 1 is: The nano-film in this example does not contain a transition layer; Other structures, parameters, and preparation processes are the same as those in Example 1.

[0060] Example 4 The difference between this example and Example 1 is: The thickness of the protective layer is 1.2 μm, the total gas flow rate is 60 sccm, and the deposition time is 1.0 h.

[0061] Other structures, parameters, and preparation processes are the same as those in Example 1.

[0062] Example 5 The difference between this example and Example 1 is: Insulating layer: with a thickness of 4.5 μm, and its composition is 62% Y-doped Si3N4 and 38% Y-doped AlN; the deposition temperature of the insulating layer is 720 °C.

[0063] Other structures, parameters, and preparation processes are the same as those in Example 1.

[0064] Example 6 The difference between this example and Example 1 is: The glass micro-melting process of the glass micro-melting layer is to heat the glass powder to 880 °C at a rate of 8 °C / min in a vacuum environment, hold it for 25 min, and then cool it to 300 °C and apply a pressure of 0.8 MPa for compaction.

[0065] Comparative Example 1 The difference between this comparative example and Example 1 is that: This comparative example does not contain a glaze layer and an epoxy adhesive layer; Other structures, parameters, and preparation processes are the same as those in Example 1.

[0066]

Application Performance of the Pressure-resistant Steel-based Nanofilm Pressure Sensor

[0067] Among them, repeatability refers to the consistency between the output values obtained by the sensor for multiple measurements of the same input quantity, reflects the random error of the sensor, and has nothing to do with hysteresis and drift; it is usually expressed as a percentage of the full-scale output; Nonlinearity refers to the maximum deviation between the actual output of the sensor and the ideal straight line (fitted straight line); expressed as a percentage of the full scale; the smaller the nonlinearity, the closer the sensor output is to the ideal linear relationship; Hysteresis refers to the maximum value of the output difference corresponding to the same input value of the sensor during the increasing and decreasing processes of the input quantity, expressed as a percentage of the full scale; Zero point refers to the output value of the sensor when the input quantity is zero (such as in a no-pressure state); the deviation between the actual zero point and the theoretical zero point may be caused by installation offset or drift; Full scale refers to the difference between the output value of the sensor at the rated maximum input quantity and the zero-point output value, which is used to normalize other errors.

[0068]

[0069] In the above-mentioned Embodiment 3, the nano-film does not include a transition layer. After the 1000VAC voltage resistance test, the stability of the nano-film is poor, resulting in a decline in measurement accuracy and a large amount of zero drift. The pressure sensor of the pressure-resistant steel-based nano-film in Comparative Example 1 does not include a glaze layer and an epoxy adhesive layer, and the lack of a protective layer leads to weak voltage resistance of the sensor, and the glass micro-melting layer is locally broken down, resulting in a large decline in the accuracy of the sensor and a very large zero offset.

[0070] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present invention can be obtained through market purchases or can be prepared by existing methods. The specific embodiments described above further elaborate on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only specific embodiments of the present invention and is not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A pressure-resistant steel-based nanofilm pressure sensor, characterized in that: include: A pressure inlet nozzle, one side of which is connected to a ceramic insulating plate; A steel-based connector is provided on one side of the ceramic insulating plate; A steel-based pressure core is provided on one side of the steel-based connector; The pressure-introducing nozzle, the ceramic insulating plate and the steel-based connecting piece are connected via a glass micro-soluble layer; The epoxy adhesive layer is arranged on one side of the glass micro-melting layer.

2. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 1, characterized in that: Meet at least one of the following conditions ①~③: ① The steel-based connector is fixedly connected to the outer shell of the lower part of the pressure core; ② The steel-based connector is connected via a glass micro-melting layer and a pressure-inducing nozzle; ③ The steel-based connector is connected via a glass micro-melting layer and a ceramic insulating plate.

3. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 1, characterized in that: The pressure core is composed of a steel base and a nano-film layer on its surface; The nano film comprises a transition layer, an insulating layer, a nickel-chromium alloy layer, a pad layer and a protective layer in sequence from bottom to top.

4. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 3, characterized in that: Meet at least one of the following conditions ①~④: ① The composition of the transition layer is Al-doped ZrO2 and Al-doped TiN; ② The composition of the insulating layer is 60-70% Y-doped Si3N4 and 30-40% Y-doped AlN; ③ The composition of the nickel-chromium alloy layer is Ni 70~80 Cr 20~30 ; ④ The component of the pad layer is Au; ⑤The component of the protective layer is SiCB.

5. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 3, characterized in that: Meet at least one of the following conditions ①~⑤: ① The thickness of the transition layer is 40-60 nm; ② The thickness of the insulating layer is 3~7μm; ③ The thickness of the nickel-chromium alloy layer is 60-90 nm; ④The thickness of the pad layer is 0.8~1.5μm; ⑤The thickness of the protective layer is 1~2μm.

6. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 1, characterized in that: Meet at least one of the following conditions ①~③: ① The thickness of the glass micro-melting layer is 1~3mm; ② The glass powder used in the glass micro-melting layer has a composition of 10-20% B2O3, 8-13% Na2O, 3-9% Al2O3 and the balance SiO2; ③ The glass micro-melting process of the glass micro-melting layer is to heat the glass powder to 870~890℃ at 5~10℃ / min in a vacuum environment and keep it warm for 20~30min, then cool it to 300~350℃ and apply 0.5~1MPa pressure for compaction.

7. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 1, characterized in that: Meet at least one of the following conditions ①~③: ① The epoxy adhesive layer is arranged on the upper surface of the glass micro-soluble layer; ② The shear strength of the epoxy adhesive used in the epoxy adhesive layer is ≥25MPa; ③ The surface resistivity of the epoxy adhesive used in the epoxy adhesive layer is ≥2.8×10 16 Ω.

8. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 1, characterized in that: A glaze layer is also provided on the lower surface of the glass slightly soluble layer; the glaze layer uses glaze ingredients including 22-28% Al2O3, 10-15% B2O3, 5-9% ZnO, 1-4% Ta2O5, 2-5% CeO2 and the balance SiO2.

9. The pressure-resistant steel-based nano-thin film pressure sensor according to claim 1, characterized in that: Meet at least one of the following conditions ①~②: ① The thickness of the ceramic insulating plate is 1~5mm; ② The content of alumina in the ceramic insulating plate is ≥ 95%.

10. Application of the pressure-resistant steel-based nano-thin film pressure sensor according to any one of claims 1 to 9 in the field of pressure testing.

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