A wear monitoring sensor suitable for large-span ceramic scrapers, its preparation method and application

Abstract

This invention belongs to the technical field of wear monitoring sensors, and discloses a wear monitoring sensor suitable for large-span ceramic scrapers, its fabrication method, and its application. The wear monitoring sensor includes a flexible substrate, a resistance measurement circuit, and a microprocessor. Multiple grids are disposed on the flexible substrate. The resistance measurement circuit is connected to the grids and measures the resistance of each individual grid, transmitting the detected resistance value to the microprocessor. The microprocessor calculates the wear length of the large-span ceramic scraper based on the received resistance value and the relationship between the wear length of the scraper and the resistance change of the grids. This invention solves the problem that existing wear detection methods cannot guarantee high-precision and rapid detection.

Description

Technical Field

[0001] This invention belongs to the technical field of wear monitoring sensors, and more specifically, relates to a wear monitoring sensor suitable for large-span ceramic scrapers, its preparation method, and its application. Background Technology

[0002] Specialty ceramics, due to their superior properties in stability, hardness, and wear resistance, are widely used in fields including aerospace, energy, electronics, medical, chemical, and metallurgy. For example, the radome is a critical component used to maintain the detection system inside the missile's seeker, ensuring its normal operation under the extreme conditions of high-speed, highly maneuverable missile flight. Its characteristics include large size, high machining precision requirements, and strict performance control. It has a crucial impact on the missile's aerodynamic characteristics and detection performance.

[0003] The additive manufacturing of meter-scale large-size ceramic components is based on drop-down digital light processing (DLP) technology. A slurry is injected every 20-30 micrometers, leveled using a large-span scraper, and then photocured. In actual production, the scraper, after prolonged use, experiences wear and even cracking due to continuous scraping of the slurry blade. This compromises the smoothness of the slurry surface in subsequent processes, leading to defects in the photocured layer structure. With multiple layers piling up, the green body becomes unusable, severely impacting the formability of the ceramic component. Therefore, real-time monitoring of scraper wear is essential.

[0004] To address the challenge of real-time monitoring of tool wear, several mature and effective measurement methods exist, including acoustic detection, optical measurement, electron microscopy, and infrared thermography. Acoustic detection indirectly determines the degree of tool wear by analyzing the sound generated by the tool, but it is unsuitable for capturing the low-frequency, weak sound signals of ceramic scrapers. Optical measurement and electron microscopy require additional large-scale inspection equipment, making them difficult to install on compact 3D printers. The heat generated during scraping is minimal and cannot be easily detected by infrared thermography.

[0005] In summary, existing technologies either cannot detect the wear of large-span scrapers in 3D printing of large-size ceramic components, or require large-volume specialized equipment that affects the printer's design, including optical paths and servo control, or cannot guarantee high-precision and rapid detection. Summary of the Invention

[0006] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a wear monitoring sensor suitable for large-span ceramic scrapers, its preparation method and application, which aims to solve the problem that the existing wear detection cannot guarantee high-precision and rapid detection.

[0007] To achieve the above objectives, according to one aspect of the present invention, a wear monitoring sensor suitable for large-span ceramic scrapers is provided. The wear monitoring sensor includes a flexible substrate, a resistance measurement circuit, and a microprocessor. Multiple grids are disposed on the flexible substrate. The resistance measurement circuit is connected to the grids and is used to measure the resistance of a single grid and transmit the detected resistance value to the microprocessor. The microprocessor is used to calculate the wear length of the large-span ceramic scraper based on the received resistance value and the relationship between the wear length of the large-span ceramic scraper and the resistance change of the grids.

[0008] Furthermore, multiple grilles are arranged in parallel, and the expression corresponding to the relationship is:

[0009]

[0010] In the formula, R is the initial total resistance, and the initial resistance value of a single grid is R0. There are a total of N resistive grids; R 新 R1 represents the total resistance after the change; ρ represents the conductivity of the conductive silver paste; l represents the wear length; and R1 represents the resistance value of the grid after the change.

[0011] Furthermore, the material of the grille is conductive silver paste.

[0012] This invention also provides a method for fabricating a wear monitoring sensor suitable for large-span ceramic scrapers. The method comprises the following steps:

[0013] S1, Imprinting is performed on the thermoplastic material on the flexible substrate to obtain a flexible substrate;

[0014] S2, a hydrophobic layer is prepared on the flexible substrate, and a hydrophilic treatment is performed in the grooves of the flexible substrate to obtain a hydrophilic and hydrophobic region that restricts droplet slip and induces droplet filling;

[0015] S3 uses electrohydraulic inkjet printing to fill droplets in the printing area of ​​a flexible substrate, randomly heating the droplets deposited in the grooves to obtain a grid.

[0016] Furthermore, by irradiating the flexible substrate with oxygen plasma, hydrophilic regions are obtained inside the trenches, and charged active molecules are deposited in these regions.

[0017] Furthermore, the surface of the flexible substrate is irradiated with plasma or UV light to achieve a localized hydrophilic change at the interface, resulting in a hydrophilic region that can attract droplets to fill it, and then the convex surface of the groove is treated with hydrophobicity.

[0018] The present invention also provides a wear monitoring sensor as described above for large-span ceramic scrapers, and its application in wear monitoring of large-span ceramic scrapers.

[0019] In summary, compared with the prior art, the wear monitoring sensor for large-span ceramic scrapers provided by this invention, its preparation method, and its application have the following main advantages:

[0020] 1. The microprocessor is used to calculate the wear length of the large-span ceramic scraper based on the received resistance value and the relationship between the wear length of the large-span ceramic scraper and the resistance change of the grid. In this way, the relationship between the minute change in resistance value and the degree of tool wear is accurately established, so that even the minute change in wear can be accurately captured and measured, thereby improving the accuracy and reliability of the measurement.

[0021] 2. The grid-type measurement can monitor tool wear in real time. As the tool is used, the resistance value changes in real time, providing timely wear information. This provides strong support for tool maintenance and better production planning in the production process.

[0022] 3. The grid can be flexibly arranged on complex tool surfaces, without being limited by the surface shape. No matter how complex the shape of the tool, the resistance grid can be accurately installed to achieve comprehensive wear monitoring.

[0023] 4. The grid-type measurement method requires fewer components, mainly including the resistance grid itself and simple circuit connections. Compared with other complex measurement devices, it does not require complex external measurement devices or special experimental environments. General circuit measurement devices can be used to measure changes in resistance values, making the construction of the device simpler and clearer. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the substrate prepared by nanoimprinting according to an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of paired embossing rollers according to an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram illustrating the use of the wear monitoring sensor for large-span ceramic scrapers provided in this embodiment of the invention;

[0027] Figure 4 yes Figure 3 A cross-sectional view of the wear monitoring sensor in the image.

[0028] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1-thermoplastic material, 2-paired embossing rollers, 3-finished substrate, 4-upper embossing roller, 5-flexible substrate, 6-lower embossing roller, 7-large span ceramic scraper, 8-wear monitoring sensor, 9-grid, 10-flexible substrate, 11-seal. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Please see Figure 4 This invention provides a wear monitoring sensor 8 suitable for large-span ceramic scrapers. The wear monitoring sensor includes a flexible substrate, a resistance measurement circuit, and a microprocessor. Multiple grids 9 are disposed on the flexible substrate. The resistance measurement circuit is connected to the grids and measures the resistance of each individual grid, transmitting the detected resistance value to the microprocessor. The microprocessor calculates the wear length of the large-span ceramic scraper based on the received resistance value and the relationship between the wear length of the large-span ceramic scraper and the resistance change of the grids.

[0031] Multiple grilles are arranged in parallel, and the expression corresponding to the relationship is:

[0032]

[0033] In the formula, R is the initial total resistance, and the initial resistance value of a single grid is R0. There are a total of N resistive grids; R 新 R1 represents the total resistance after the change; ρ represents the conductivity of the conductive silver paste; l represents the wear length; and R1 represents the resistance value of the grid after the change. The grid is made of conductive silver paste and is encapsulated with a high-temperature carbon film to form a seal 11.

[0034] Please see Figure 1 , Figure 2 and Figure 3 The present invention also provides a method for preparing a wear monitoring sensor suitable for large-span ceramic scrapers. The method is used to prepare the wear monitoring sensor for large-span ceramic scrapers as described above, and mainly includes the following steps:

[0035] S1, The thermoplastic material on the flexible substrate 10 is imprinted to obtain the flexible substrate 5.

[0036] Specifically, a roller nanoimprinting technique is used to prepare the flexible substrate. The imprinting material can be thermoplastic PMMA (1) or an organic photocurable material using a photocuring process. A pair of imprinting rollers are used to achieve double-sided staggered imprinting. The finished substrate (3) requires pretreatment such as cleaning to ensure a smooth and clean surface that meets functional interface requirements.

[0037] The embossing process uses a pair of embossing rollers 2, which include an upper embossing roller 4 and a lower embossing roller 6, and the scraper is a large-span ceramic scraper 7.

[0038] S2, a hydrophobic layer is prepared on the flexible substrate, and a hydrophilic treatment is performed in the grooves of the flexible substrate to obtain a hydrophilic-hydrophobic region that restricts droplet slip and induces droplet filling.

[0039] The substrate surface is irradiated with plasma or UV light to achieve a localized hydrophilic change at the interface, resulting in a hydrophilic region that can attract droplets for filling. The upper surface of the substrate is then hydrophilically treated with oxygen plasma, and the grooves and convex surfaces are hydrophobically treated using methods such as masking, forming a hydrophilic-hydrophobic structure that is easy to electrohydraulic inkjet print.

[0040] In one embodiment, a flexible substrate is irradiated with oxygen plasma to create a hydrophilic region inside the trenches, while simultaneously depositing charged active molecules into the hydrophilic region.

[0041] S3 divides the printing structure, then plans and designs the printing path, imports the printing path into the printing equipment, and performs calibration and pre-processing on the printing equipment.

[0042] Atmospheric plasma technology is used for surface modification, and a large number of charged active molecules are deposited on the surface of the hydrophilic region. This charge can achieve a traction effect on the subsequent electrofluid spraying droplets, realizing high-precision self-aligned filling of conductive silver paste.

[0043] S4 involves using electrohydraulic inkjet printing to fill droplets in the printing area of ​​a flexible substrate, randomly heating the droplets deposited in the grooves, and then obtaining a grid.

[0044] After the droplets from electrohydraulic inkjet printing fill the area to be printed, a post-heating process is used to heat the ink deposited in the grooves, using localized high-density heat to evaporate the solvent in the ink and generate a grid. Conductive silver paste is used as the printing material, and the line width of the rollers is 2μm with a spacing of 2μm.

[0045] Specifically, the post-heating process can utilize high-energy-density laser sintering, lens-focused infrared sintering, or xenon lamp sintering. Other methods can also be used to achieve high heat and sintering solidification. Preferably, laser sintering is used because it features high instantaneous power, small spot area, and rapid localized heating, thereby achieving selective sintering of the grooved regions.

[0046] There is a clear quantitative relationship between the resistance change of the resistive grid and the degree of tool wear. For parallel resistive grids, the reciprocal of the total resistance is equal to the sum of the reciprocals of the individual resistances. Assuming that initially, the resistance of each resistive grid is R0, and there are a total of N resistive grids (20 lines), then the initial total resistance is...

[0047] When the resistance value of a resistor grid changes from R0 to R1 (due to the reduction in linewidth caused by wear), and there are still N resistor grids, the new total resistance is: Where ρ is the conductivity of the conductive silver paste, and l is the wear length.

[0048] Considering the influence of the environment on the resistance value, the relationship between the resistance value and the degree of wear can be established through the following steps:

[0049] Calibration data was established, and a series of calibration experiments were conducted using samples with varying degrees of tool wear, measuring the resistance values ​​of their resistive grids. Throughout this process, the stability of other influencing factors was ensured to accurately analyze the relationship between resistance values ​​and wear levels, taking temperature effects into account. A temperature sensor was used to monitor ambient temperature, and resistance values ​​were corrected accordingly. A humidity sensor was used to monitor humidity and correct for resistance values. The influence of the environment on resistance values ​​was corrected through a pre-calibration process. By measuring the resistance values ​​of the resistive grids under different environmental conditions, a correction model for environmental influences was established.

[0050] Data analysis involves statistically analyzing the resistance values ​​obtained from the calibration experiment with the corresponding tool wear data. Statistical methods and regression analysis can be used to find the mathematical relationship between the resistance value and the wear degree.

[0051] A relational model is established based on the data analysis results, resulting in a quantitative model that expresses the mathematical relationship between changes in resistance and tool wear. This model should basically conform to the theoretical relational equations mentioned above, while also taking into account environmental influences such as temperature and humidity; its specific form depends on the analysis results.

[0052] The present invention also provides a wear monitoring sensor as described above for large-span ceramic scrapers, and its application in wear monitoring of large-span ceramic scrapers.

[0053] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A wear monitoring sensor suitable for large-span ceramic scrapers, characterized in that: The wear monitoring sensor includes a flexible substrate, a resistance measurement circuit, and a microprocessor. Multiple grids are disposed on the flexible substrate. The resistance measurement circuit is connected to the grids and is used to measure the resistance of a single grid and transmit the detected resistance value to the microprocessor. The microprocessor is used to calculate the wear length of the large-span ceramic scraper based on the received resistance value and the relationship between the wear length of the large-span ceramic scraper and the resistance change of the grid. Multiple grilles are arranged in parallel, and the expression corresponding to the relationship is: In the formula, R0 is the initial total resistance, and the initial resistance value of a single grid is R0. There are a total of N resistance grids. The total resistance after the change; ρ The conductivity of the conductive silver paste; This refers to the wear length. This represents the resistance value of the grid after the change.

2. The wear monitoring sensor for large-span ceramic scrapers as described in claim 1, characterized in that: The material of the grille is conductive silver paste.

3. A method for preparing a wear monitoring sensor suitable for large-span ceramic scrapers, characterized in that: The preparation method is used to prepare the wear monitoring sensor suitable for large-span ceramic scrapers according to any one of claims 1-2, and includes the following steps: S1, Imprinting is performed on the thermoplastic material on the flexible substrate to obtain a flexible substrate; S2, a hydrophobic layer is prepared on the flexible substrate, and a hydrophilic treatment is performed in the grooves of the flexible substrate to obtain a hydrophilic and hydrophobic region that restricts droplet slip and induces droplet filling; S3 uses electrohydraulic inkjet printing to fill droplets in the printing area of ​​a flexible substrate, randomly heating the droplets deposited in the grooves to obtain a grid.

4. The method for preparing a wear monitoring sensor suitable for large-span ceramic scrapers as described in claim 3, characterized in that: By irradiating a flexible substrate with oxygen plasma, hydrophilic regions are obtained inside the trenches, and charged active molecules are deposited in these regions.

5. The method for preparing a wear monitoring sensor suitable for large-span ceramic scrapers as described in claim 3, characterized in that: The surface of the flexible substrate is irradiated with plasma or UV light to achieve a localized hydrophilic change at the interface, resulting in a hydrophilic region that can attract droplets to fill it. Then, the convex surface of the groove is treated with hydrophobicity.

6. The application of the wear monitoring sensor according to any one of claims 1-2 for large-span ceramic scrapers in wear monitoring of large-span ceramic scrapers.

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