Vulcanization-resistant thick-film resistor

Abstract

The invention relates to the technical field of resistors, in particular to a vulcanization-resistant thick-film resistor which comprises a tin plating layer, a nickel plating layer arranged in the tin plating layer, conductor layers located on the two sides of the nickel plating layer, a substrate arranged in the middle of the conductor layers and a resistance layer arranged on the substrate. A resistor protection layer is arranged on the upper side of the upper electrode assembly; the resistor protection layer comprises a sacrificial layer and a stable layer, the stable layer is arranged on the upper side of the electrode assembly, the sacrificial layer is fixed on the upper side of the stable layer, the stable layer is made of a high-vulcanization-resistance material, and the sacrificial layer is made of a low-activity conductive phase material; a self-repairing layer is arranged on the upper side of the resistance layer, the self-repairing layer comprises a micro-repairing capsule, and a corrosion inhibitor is arranged in the micro-repairing capsule. According to the invention, the bottleneck of the prior art is broken through from the angles of structure protection and dynamic repair, and the reliability of the vulcanization-resistant thick-film resistor can be remarkably improved by combining the structure protection and the dynamic repair.

Description

Technical Field

[0001] The present invention relates to the technical field of resistors, and particularly to a sulfur-resistant thick film resistor. Background Art

[0002] A thick film resistor is a resistor formed by printing a thick film resistor paste on a substrate and then sintering it at a high temperature. Sulfur resistance may mean that this resistor can resist the corrosion of sulfides, because in some sulfur-containing environments, sulfides can cause the performance of the resistor to degrade or even fail.

[0003] Chinese Patent No. CN219370711U discloses an anti-sulfur and high-voltage-resistant thick film chip resistor, including: a first tin layer, a ceramic substrate, a second tin layer and a silver electrode. A first notch is formed in the middle of the first tin layer, and one end of the ceramic substrate is inserted into the first notch. A second notch is formed in the middle of the second tin layer, and the other end of the ceramic substrate is inserted into the second notch. The above application prints a specially lengthened circuit in the middle of the silver electrode, so that it can withstand a higher voltage, and is provided with a first protective layer and a second protective layer.

[0004] However, after the existing resistor layer is damaged, it cannot self-repair, resulting in a reduced resistance to sulfurization and affecting the normal use of the resistor layer. Summary of the Invention

[0005] The purpose of the present invention is to solve the defect that in the prior art, after being damaged, it cannot self-repair, resulting in a reduced resistance to sulfurization and affecting the normal use of the resistor layer, and to propose a sulfur-resistant thick film resistor.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions: A sulfur-resistant thick film resistor includes: a tin plating layer, a nickel plating layer disposed inside the tin plating layer, conductor layers on both sides of the nickel plating layer, a substrate disposed in the middle of the conductor layers, and a resistor layer disposed on the substrate. Electrode assemblies are provided on the upper and lower surfaces of the substrate, and a resistor protective layer is provided on the upper side of the electrode assembly provided on the upper surface. The resistor protective layer includes a sacrificial layer and a stable layer. The stable layer is disposed on the upper side of the electrode assembly, the sacrificial layer is fixed on the upper side of the stable layer, the stable layer is made of a high sulfur-resistant material, and the sacrificial layer is made of a low-activity conductive phase material. A self-repairing layer is provided on the upper side of the resistor layer. The self-repairing layer includes micro-repair capsules. The inside of the micro-repair capsules is set as a corrosion inhibitor, and the outer shell is provided with two layers, namely an anti-heat layer located on the outside and a wrapping layer located on the inside.

[0007] Preferably, the electrode assembly includes two upper electrode blocks and two lower electrode blocks. The two upper electrode blocks are arranged on both sides above the substrate, and the two lower electrode blocks are arranged on both sides below the substrate.

[0008] Preferably, a plurality of arc-shaped raised strips are arranged on the upper surface of the sacrificial layer. There are diversion ramps between the plurality of arc-shaped raised strips. The diversion ramps are inclined to both sides and are used for diverting from the middle to both sides.

[0009] Preferably, a glass glaze protective layer is arranged above the resistance layer, and the glass glaze protective layer is filled with silicon dioxide or oxidized nanoparticles inside.

[0010] Preferably, the stabilizing layer is made of ruthenium dioxide and is used to maintain the resistance stability. The sacrificial layer is made of tungsten carbide and is used for sacrificially blocking sulfur erosion.

[0011] Preferably, the self-healing layer further includes a slurry. The micro-repair capsules are mixed inside the slurry. The self-healing layer is arranged between the resistance protective layer and the resistance layer and is used to protect the resistance layer.

[0012] Preferably, the micro-repair capsules are spherical, and the size of the micro-repair capsules needs to be smaller than the conductive phase particles in the slurry.

[0013] Preferably, the corrosion inhibitor is zincate, the heat-resistant layer is a rigid layer made of silicon dioxide, and the wrapping layer is a flexible layer made of polyimide.

[0014] Preferably, silicon carbide nanowires are arranged inside the heat-resistant layer, and chitosan response strips are arranged inside the wrapping layer.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The design of the resistance protective layer breaks through the bottleneck of the prior art from the perspectives of structural protection and dynamic repair by constructing a multi-layer resistance structure and using the physical and chemical properties of different materials for collaborative protection. The self-healing layer realizes dynamic protection by embedding micro-repair capsules. The combination of the two can significantly improve the reliability of the sulfur-resistant thick film resistor; 2. By arranging a plurality of arc-shaped raised strips on the sacrificial layer, the infiltrated sulfur is shunted, and the sulfur is dispersed and transferred to the sacrificial layer. At the same time, inclined diversion slopes are arranged below the plurality of arc-shaped raised strips, which can divert the infiltrated sulfur to both sides. The moving sulfur will uniformly contact and react with the low-activity conductive material on the sacrificial layer, improving the service life of the entire sacrificial layer and ensuring the sulfur blocking effect; 3. The inner layer is made of high-stability materials such as ruthenium dioxide to maintain the long-term stability of the resistance value and avoid performance failure caused by the corrosion of the outer layer. The outer layer can use low-cost materials to reduce the consumption of precious metals, thereby reducing the overall cost. Moreover, the multi-layer printing technology has been maturely applied in the manufacture of thick film resistors; 4. Fill silicon dioxide or oxidized nanoparticles with a mass ratio of 5-10% inside the glass glaze protective layer. The nanoparticles fill the micropores, improve the density, and reduce the sulfur penetration path, thereby enhancing the protection effect; 5. Since there is a risk of high-temperature sintering and rupture of the micro-repair capsules during use, silicon carbide nanowires are used to reinforce the wall material inside the thermal-resistant layer to improve the thermal shock resistance of the micro-repair capsules; 6. To avoid the premature release of the corrosion inhibitor, a pH-responsive wall material is designed so that the micro-repair capsules dissolve only in the acidic environment caused by sulfides, reducing the waste of the corrosion inhibitor. Brief Description of the Drawings

[0016] Figure 1 It is a schematic cross-sectional structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention; Figure 2 It is a schematic front structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention; Figure 3 It is a schematic internal structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention; Figure 4 It is a schematic glass glaze protective layer structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention; Figure 5 It is a schematic self-repair layer structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention; Figure 6 It is a schematic stable layer structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention; Figure 7 It is a schematic micro-repair capsule structure diagram of a sulfidation-resistant thick film resistor proposed by the present invention.

[0017] In the figure: 1. Tin plating layer; 2. Nickel plating layer; 3. Conductor layer; 4. Substrate; 5. Resistance layer; 6. Electrode assembly; 61. Upper electrode block; 62. Lower electrode block; 7. Resistance protective layer; 71. Sacrificial layer; 72. Stable layer; 8. Self-repair layer; 81. Micro-repair capsule; 811. Corrosion inhibitor; 812. Thermal-resistant layer; 813. Wrapping layer; 82. Slurry; 9. Arc-shaped raised strip; 10. Glass glaze protective layer; 11. Silicon carbide nanowire; 12. Chitosan response strip. Detailed Embodiments

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0019] Terms such as "upper", "lower", "left", "right", "middle", and "one" cited in the present invention are only for the convenience of clear narration, rather than to limit the scope of implementation of the present invention. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope of implementation of the present invention.

[0020] Referring to Figures 1 - 7 , a sulfur-resistant thick film resistor includes: a tin plating layer 1, a nickel plating layer 2 disposed inside the tin plating layer 1, conductor layers 3 on both sides of the nickel plating layer 2, a substrate 4 disposed in the middle of the conductor layers 3, and a resistor layer 5 disposed on the substrate 4. Electrode assemblies 6 are provided on the upper and lower surfaces of the substrate 4, and a resistor protection layer 7 is provided on the upper side of the electrode assembly 6 provided on the upper surface; The resistor protection layer 7 includes a sacrificial layer 71 and a stable layer 72. The stable layer 72 is disposed on the upper side of the electrode assembly 6, the sacrificial layer 71 is fixed on the upper side of the stable layer 72, the stable layer 72 is made of a highly sulfur-resistant material, and the sacrificial layer 71 is made of a low-activity conductive phase material; A self-repair layer 8 is provided on the upper side of the resistor layer 5. The self-repair layer 8 includes micro-repair capsules 81. The inside of the micro-repair capsules 81 is set as a corrosion inhibitor 811, and the outer shell is provided with two layers, namely an anti-heat layer 812 located on the outside and a wrapping layer 813 located on the inside.

[0021] In the embodiments applying the above technical solutions, the sulfidation problem of the resistor may come from the reaction between sulfides in the environment and metals in the resistor material, generating metal sulfides, resulting in changes in the resistance value or even open circuit.

[0022] The design of the resistor protection layer 7 achieves collaborative protection by constructing a multi-layer resistor structure and utilizing the physical and chemical properties of different materials. The self-repair layer 8 realizes dynamic protection by embedding micro-repair capsules 81.

[0023] The resistor protection layer 7 breaks through the bottleneck of the existing technology from the perspective of structural protection through gradient design, and the addition of the self-repair layer 8 breaks through from the perspective of dynamic repair. The combination of the two can significantly improve the reliability of the sulfur-resistant thick film resistor.

[0024] The preferred technical solution in this embodiment: Referring to Figures 3 - 4 , the electrode assembly includes two upper electrode blocks 61 and two lower electrode blocks 62. The two upper electrode blocks 61 are disposed on both sides above the substrate 4, and the two lower electrode blocks 62 are disposed on both sides below the substrate 4; During normal use, electricity is passed through the upper and lower electrode blocks. When current passes through, electrons flow in the paths between the conductive particles in the resistance layer 5, thereby generating resistance.

[0025] Referring to Figures 5 - 6 , a plurality of arc-shaped raised strips 9 are provided on the upper surface of the sacrificial layer 71. There are diversion ramps between the plurality of arc-shaped raised strips 9. The diversion ramps are inclined to both sides for diverting from the middle to both sides. The stable layer 72 is made of ruthenium dioxide and is used to maintain the resistance stability. The sacrificial layer 71 is made of tungsten carbide and is used for sacrificial blocking of sulfur erosion.

[0026] The existing sacrificial layer 71 usually uses a single passivation film for protection. The traditional single material layer is prone to failure due to local corrosion. In this application, through the design of the gradient resistance layer 5, by constructing a multi-layer resistance structure, the physical and chemical properties of different materials are used for collaborative protection. Moreover, the outer sacrificial layer 71 is mostly made of low-activity conductive materials, such as tungsten carbide or doped metal oxides, which preferentially react with sulfides to form a dense passivation film and delay the penetration of sulfur.

[0027] However, during the process of sulfur penetration, it is easy for sulfur to penetrate a fixed position, causing the sacrificial layer 71 to be broken through at a single point, reducing the service life of the entire sacrificial layer 71. By providing a plurality of arc-shaped raised strips 9 on the sacrificial layer 71, the infiltrated sulfur is shunted, and the sulfur is dispersed and transferred to the sacrificial layer 71. At the same time, inclined diversion slopes are provided below the plurality of arc-shaped raised strips 9, which can divert the infiltrated sulfur to both sides. The moving sulfur will uniformly contact and react with the low-activity conductive material on the sacrificial layer 71, improving the service life of the entire sacrificial layer 71 and ensuring the sulfur blocking effect.

[0028] The inner layer selects high-stability materials, such as ruthenium dioxide, to maintain the long-term stability of the resistance value and avoid performance failure caused by outer layer corrosion.

[0029] The outer layer can use low-cost materials, reduce the use of precious metals, reduce the comprehensive cost, and the multi-layer printing technology has been maturely applied in the manufacture of thick film resistors.

[0030] Referring to Figure 4 , a glass glaze protection layer 10 is provided above the resistance layer 5, and the glass glaze protection layer 10 is filled with silicon dioxide or oxidized nanoparticles inside; A glass glaze protection layer 10 is provided on the resistance layer 5, and 5-10% of silicon dioxide or oxidized nanoparticles by mass are filled inside the glass glaze protection layer 10. The nanoparticles fill the micropores, improve the density, reduce the sulfur penetration path, and thus improve the protection effect.

[0031] Referring to Figures 4 - 7, the self-repairing layer 8 further includes a slurry 82, the micro-repairing capsules 81 are mixed inside the slurry 82, and the self-repairing layer 8 is arranged between the resistor protection layer 7 and the resistor layer 5 to protect the resistor layer 5; The micro-repair capsule 81 is spherical, and the size of the micro-repair capsule 81 needs to be smaller than the conductive phase particles in the slurry 82; The corrosion inhibitor 811 is zincate, the heat-resistant layer 812 is a rigid layer made of silicon dioxide, and the wrapping layer 813 is a flexible layer made of polyimide.

[0032] The self-healing corrosion inhibitor 811 achieves dynamic protection by embedding micro-repair capsules 81 in the resistor slurry 82, where the corrosion inhibitor 811 is such as zincate or organic amine. Traditional corrosion inhibitors 811 are prone to failure after one-time release, and the self-healing design can respond to corrosion signals multiple times, thereby improving protection efficiency.

[0033] The micro-repair capsules 81 are generally made into spherical shapes. When prepared by processes such as spray drying and emulsion polymerization, the surface tension of the liquid causes the droplets to naturally shrink into spheres. The spheres have good fluidity and are easy to be evenly dispersed in the thick film slurry 82. They also have high mechanical strength, consistent wall thickness, and strong resistance to sintering thermal shock.

[0034] Reference Figure 7 The heat-resistant layer 812 is provided with silicon carbide nanowires 11 inside, and the wrapping layer 813 is provided with chitosan response strips 12 inside.

[0035] Since the micro-repair capsule 81 has the risk of sintering and cracking during use, silicon carbide nanowires 11 are used to strengthen the wall material inside the heat-resistant layer 812 to improve the thermal shock resistance of the micro-repair capsule 81; At the same time, in order to avoid the corrosion inhibitor 811 from being released prematurely, a pH-responsive wall material is designed through the chitosan response strip 12 so that the micro-repair capsule 81 only dissolves in an acidic environment caused by sulfide, thereby reducing the waste of the corrosion inhibitor 811.

[0036] When sulfide intrusion causes local pH changes or mechanical stress, the micro-repair capsule 81 ruptures to release the corrosion inhibitor 811, which neutralizes the sulfide through adsorption or film-forming reaction. The precise release reduces the amount of corrosion inhibitor 811 used and reduces its toxic impact on the environment.

[0037] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A sulfurization resistant thick film resistor comprising: A tin-plated layer, a nickel-plated layer arranged inside the tin-plated layer, a conductor layer located on both sides of the nickel-plated layer, a substrate arranged in the middle of the conductor layer, and a resistor layer arranged on the substrate, wherein an electrode assembly is arranged on the upper and lower sides of the substrate, and a resistor protection layer is arranged on the upper side of the electrode assembly arranged on the upper side; The resistance protection layer includes a sacrificial layer and a stabilizing layer, wherein the stabilizing layer is arranged on the upper side of the electrode assembly, the sacrificial layer is fixed on the upper side of the stabilizing layer, the stabilizing layer is made of a highly sulfidation-resistant material, and the sacrificial layer is made of a low-activity conductive phase material; A self-repairing layer is arranged on the upper side of the resistance layer. The self-repairing layer includes micro-repairing capsules. The interior of the micro-repairing capsules is provided with corrosion inhibitors, and the outer shell is provided with two layers, namely, a heat-resistant layer located on the outside and a wrapping layer located on the inside.

2. The sulfurization resistant thick film resistor according to claim 1, characterized in that: The electrode assembly includes two upper electrode blocks and two lower electrode blocks. The two upper electrode blocks are arranged on both sides above the substrate, and the two lower electrode blocks are arranged on both sides below the substrate.

3. The sulfurization resistant thick film resistor according to claim 1, characterized in that: A plurality of arc-shaped protruding strips are arranged on the upper surface of the sacrificial layer, and a flow guiding ramp is arranged between the plurality of arc-shaped protruding strips. The flow guiding ramp is inclined toward both sides and is used for guiding flow from the middle to both sides.

4. The sulfurization resistant thick film resistor according to claim 1, characterized in that: A glass glaze protective layer is arranged above the resistance layer, and silicon dioxide or oxide nanoparticles are filled in the glass glaze protective layer.

5. The sulfurization resistant thick film resistor according to claim 1, characterized in that: The stabilizing layer is made of ruthenium dioxide for maintaining resistance stability, and the sacrificial layer is made of tungsten carbide for sacrificially blocking sulfur corrosion.

6. The sulfurization resistant thick film resistor according to claim 1, characterized in that: The self-repairing layer also includes slurry, the micro-repairing capsules are mixed inside the slurry, and the self-repairing layer is arranged between the resistance protection layer and the resistance layer to protect the resistance layer.

7. The sulfurization resistant thick film resistor according to claim 6, characterized in that: The micro-repair capsule is spherical, and the size of the micro-repair capsule needs to be smaller than the conductive phase particles in the slurry.

8. The sulfurization resistant thick film resistor according to claim 1, characterized in that: The corrosion inhibitor is zincate, the heat-resistant layer is a rigid layer made of silicon dioxide, and the wrapping layer is a flexible layer made of polyimide.

9. The sulfurization resistant thick film resistor according to claim 8, characterized in that: Silicon carbide nanowires are arranged inside the heat-resistant layer, and chitosan response strips are arranged inside the wrapping layer.

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