Radar circuit board product processing method based on laser blind hole design

Abstract

The invention relates to the technical field of circuit board processing, in particular to a radar circuit board product processing method based on laser blind hole design. The method comprises the following steps: determining a laser blind hole processing environment based on whether an oxidizable material exists in a laser scanning path of a radar circuit board to be processed; based on the blind hole depth of the radar circuit board to be machined and the laser blind hole machining environment, whether a flying material shielding device is added or not or whether a gas-assisted machining method is used or not is determined during laser blind hole machining; when the gas-assisted machining method is used, the gas-assisted machining method is determined based on the magnetic conductivity of the area where laser blind hole machining is not conducted and the thermal diffusion coefficient of the blind hole material to be machined; whether the machining process is adjusted or not is determined according to the roughness of the blind hole of the radar circuit board machined through the gas-assisted machining method and the depth of the blind hole, by adding an auxiliary method for the laser blind hole machining process, the machining precision of the laser blind hole is improved, and the machining quality of the blind hole is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board processing, and in particular to a radar circuit board product processing method based on laser blind hole design. Background Art

[0002] With the rapid development of radar technology, radar circuit boards, as a key component of radar systems, have increasingly higher performance requirements. Radar circuit boards usually require high integration and miniaturization. Blind holes are important structures for achieving electrical connections between multiple layers of circuit boards. Laser blind hole processing technology has been widely used in radar circuit board manufacturing due to its high precision and high flexibility. However, in the process of laser blind hole processing, there are many technical challenges. In traditional processing, the control means for flying materials (material debris generated during the processing process, etc.) are relatively single. When the depth of the blind hole reaches a certain level, the flying material problem will become more prominent. When processing deeper blind holes in an air environment, if only simple processing methods are relied upon, flying materials may be re-deposited on the surface of the blind hole or the circuit board, affecting the dimensional accuracy and surface quality of the blind hole.

[0003] Chinese patent application publication number: CN106793572A discloses a method for laser blind hole drilling of a multilayer circuit board, which includes the following steps: micro-etching the surface copper to be processed in the multilayer circuit board to micro-etch away part of the copper layer and retain the surface copper of a set thickness; browning the copper surface layer of the set thickness and oxidizing the surface copper to blacken it to form a transition layer; using a CO2 laser to perform laser drilling at a specified position of the transition layer of the multilayer circuit board to form a blind hole. The technical solution of the invention can improve the ability to make the blind hole thickness-to-diameter ratio. After testing, when the blind hole thickness-to-diameter ratio reaches 1.4:1, there will be no blind hole voids or cracks, thereby improving the blind hole forming effect.

[0004] It can be seen that the existing technology has the problem that the analysis of the laser blind hole forming process of the radar circuit board is not accurate enough, which leads to the failure to select effective auxiliary methods and the low quality of the processed blind holes. Summary of the invention

[0005] To this end, the present invention provides a radar circuit board product processing method based on laser blind hole design, so as to overcome the problem in the prior art that the analysis of the radar circuit board laser blind hole forming process is not accurate enough, resulting in the inability to select effective auxiliary methods and causing low quality of the processed blind holes.

[0006] To achieve the above object, the present invention provides a radar circuit board product processing method based on laser blind hole design, comprising: Obtain blind hole processing data, laser working data and radar circuit board data to be processed; Determine whether the laser blind hole processing environment is an air environment or an oxygen-free environment based on whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed; Based on the blind hole depth of the radar circuit board to be processed and the laser blind hole processing environment, determine whether to add a flying material shielding device when performing laser blind hole processing, or whether to use a gas-assisted processing method; When the gas-assisted processing method is used, the gas-assisted processing is determined to be performed by the gas temperature adjustment method or the electric field-assisted method based on the magnetic permeability of the area not subjected to the laser blind hole processing and the thermal diffusion coefficient of the blind hole material to be processed; According to whether there is a blind hole inner wall with a roughness greater than a preset roughness and whether the blind hole depth with a roughness greater than a preset roughness meets the preset blind hole depth condition after being processed by the gas-assisted processing method, it is determined whether to adjust the preset depth and the preset magnetic permeability threshold.

[0007] Further, determining whether the laser blind hole processing environment is an air environment or an oxygen-free environment includes: If there are easily oxidizable materials in the laser scanning path of the radar circuit board to be processed, make sure that the laser blind hole processing environment is an oxygen-free environment; If there is no easily oxidizable material in the laser scanning path of the radar circuit board to be processed, it is determined that the laser blind hole processing environment is an air environment.

[0008] Furthermore, whether to add a flying material shielding device during laser blind hole processing, or whether to use a gas-assisted processing method includes: If the blind hole depth of the radar circuit board to be processed is less than the preset depth, it is determined that there is no need to add a flying material shielding device and there is no need to use a gas-assisted processing method; If the blind hole depth of the radar circuit board to be processed is greater than or equal to the preset depth and the laser blind hole processing environment is an air environment, it is determined to add a flying material shielding device; If the blind hole depth of the radar circuit board to be processed is greater than or equal to the preset depth and the laser blind hole processing environment is an oxygen-free environment, it is determined to use the gas-assisted processing method.

[0009] Furthermore, the preset depth is determined according to an average value of blind hole depths of a number of radar circuit boards to be processed.

[0010] Further, the determination to perform gas-assisted processing by a gas temperature regulation method or an electric field assisted method includes: If the thermal diffusion coefficient of the blind hole material to be processed is less than the preset thermal diffusion coefficient and the magnetic permeability of the area not subjected to laser blind hole processing is less than or equal to the preset magnetic permeability threshold, it is determined to adopt the gas temperature adjustment method for gas-assisted processing; If the thermal diffusion coefficient of the blind hole material to be processed is less than the preset thermal diffusion coefficient and the magnetic permeability of the area not subjected to laser blind hole processing is greater than the preset magnetic permeability threshold, it is determined to use the gas temperature adjustment method and the electric field auxiliary method for gas-assisted processing; If the thermal diffusion coefficient of the blind hole material to be processed is greater than or equal to the preset thermal diffusion coefficient, it is determined to use the electric field assisted method for gas assisted processing.

[0011] Further, the determining whether to adjust the preset depth and the preset magnetic permeability threshold comprises: If the radar circuit board has a blind hole inner wall with a roughness greater than a preset roughness after being processed by the gas-assisted processing method and the blind hole depth with a roughness greater than the preset roughness meets the preset blind hole depth condition, it is determined to adjust the preset depth; If, after being processed by the gas-assisted processing method, the radar circuit board has a blind hole inner wall with a roughness greater than a preset roughness and the blind hole depth with a roughness greater than the preset roughness does not meet the preset blind hole depth condition, it is determined to adjust the preset magnetic permeability threshold.

[0012] Furthermore, the preset roughness is determined according to a historical average roughness of blind holes of radar circuit boards of the same model processed by a gas-assisted processing method.

[0013] Furthermore, the adjustment amount of the preset depth is negatively correlated with the roughness of the blind hole of the radar circuit board after processing using the gas-assisted processing method, and the adjustment amount of the preset magnetic permeability threshold is positively correlated with the depth of the blind hole whose roughness is greater than the preset roughness.

[0014] Further, determining that the blind hole depth having a roughness greater than a preset roughness meets a preset blind hole depth condition includes that an absolute value of a difference between the blind hole depth and a preset blind hole depth is less than a preset difference, and the preset blind hole depth is the required processing depth of the blind hole.

[0015] Furthermore, the determination of adopting the gas temperature adjustment method for gas-assisted processing includes determining the gas temperature according to the thermal diffusion coefficient of the blind hole material and the laser working power.

[0016] Compared with the prior art, the beneficial effect of the present invention is that the present invention can effectively prevent easily oxidized metal elements such as copper, iron, and nickel from chemically reacting with oxygen during laser processing by carefully judging whether there are easily oxidized materials in the laser scanning path, and then selectively selecting an air environment or an oxygen-free environment for processing. For example, if copper is in an air environment under the action of a high-temperature laser, copper oxide is easily generated, which will change the original electrical and mechanical properties of the material, reduce the conductivity of the circuit board, and increase the surface roughness. However, by using a suitable oxygen-free environment (such as a nitrogen environment, an argon environment, or a helium environment) for processing, such oxidation phenomena can be avoided, ensuring that the inner wall material of the processed blind hole has stable performance, maintaining good electrical connectivity, and improving the overall signal transmission quality and performance of the radar circuit board. For some radar circuit boards with high precision requirements, a tiny oxide layer may cause problems such as increased signal loss or signal interference. Accurately selecting a processing environment can minimize the quality risks caused by oxidation, ensure that the blind hole dimensional accuracy, roughness, and other indicators meet high standards, and help produce high-quality and high-performance radar circuit board products.

[0017] Furthermore, the present invention determines that there is no need to add a flying material shielding device and no need to use a gas-assisted processing method for the case where the blind hole depth is less than a preset depth. This is because a shallower blind hole generates relatively less flying material during processing, and the impact on the processing quality and environment is limited. At this time, no additional devices and auxiliary processing methods are used. Only when the blind hole depth reaches a certain level (greater than or equal to the preset depth) and meets the corresponding processing environment conditions, a flying material shielding device or a gas-assisted processing method is added. This reasonably allocates resources and reduces the overall processing cost. When the blind hole depth is greater than or equal to the preset depth and the laser blind hole processing environment is an air environment, a flying material shielding device is added. A deeper blind hole is prone to generate more flying material during processing, and in an air environment, flying material is more likely to splash around and re-deposit, affecting the processing quality. At this time, a flying material shielding device is used, which can effectively block the disordered diffusion of flying material so that it does not affect The gas-assisted processing method is used when the depth of the blind hole is greater than or equal to the preset depth and the laser blind hole processing environment is an oxygen-free environment. The oxygen-free environment is usually a special environment created to avoid oxidation of easily oxidizable materials. If the processing of deeper blind holes relies solely on conventional methods in this environment, problems such as heat accumulation and poor control of flying materials are prone to occur. The gas-assisted processing method can take away heat and guide flying materials through gas blowing, improve heat transfer and flying material movement during processing, and help improve the quality of blind hole processing. For example, the inner wall of the blind hole is smoother and the size is more accurate, ensuring that the signal transmission and other performance of the radar circuit board in subsequent use are not affected by processing quality problems.

[0018] Furthermore, the present invention adopts different gas-assisted processing strategies for materials with different thermal diffusivities by considering the thermal diffusivity, a key parameter reflecting the thermophysical properties of the material. For materials with a small thermal diffusivity, heat is easily accumulated during the processing. If it is not specifically regulated, it is easy to cause local overheating of the inner wall of the blind hole, causing excessive melting and vaporization of the material, thereby causing quality problems such as increased roughness of the inner wall of the blind hole and decreased dimensional accuracy. When the gas temperature regulation method is used according to the thermal diffusivity or combined with the electric field assisted method, the heat distribution in the processing area can be effectively regulated. For example, the gas temperature is adjusted to adjust the temperature of the material. Adjust to take away excess heat, or use electric field to assist in guiding flying materials to avoid bad deposition due to overheating, thereby improving the quality indicators of blind hole processing such as dimensional accuracy and inner wall roughness, and ensuring that the processed blind holes meet the requirements of high-quality radar circuit boards. For materials with large thermal diffusion coefficients, the heat dissipation is relatively fast. The use of electric field-assisted methods for gas-assisted processing can better utilize the guiding effect of the electric field on flying materials, so that the flying materials move in the desired direction, avoid their disordered accumulation affecting the quality of blind holes, ensure the consistency and accuracy of blind hole processing, and improve the overall processing quality. The magnetic permeability of the area not processed by laser blind holes is also an impact When the magnetic permeability is less than or equal to the preset magnetic permeability threshold, it means that the response characteristics of the material to the electromagnetic field are within a specific range. The gas temperature adjustment method is used for gas-assisted processing. Under this magnetic permeability condition, the temperature adjustment function of the gas can be used to effectively control heat and flying materials without being disturbed by complex electromagnetic fields, making the processing process more stable, which helps to improve the quality stability of blind hole processing and reduce quality defects caused by abnormal movement and deposition of flying materials due to magnetic permeability-related factors. When the magnetic permeability is greater than the preset magnetic permeability threshold, the behavior of the material in the electromagnetic field changes greatly, and flying materials are more likely to be produced. The material is more significantly affected by the magnetic field. At this time, gas-assisted processing is performed in a combination of gas temperature regulation method and electric field auxiliary method. The advantages of gas temperature regulation to improve the thermal environment and electric field to accurately guide the flying material can be comprehensively utilized to better cope with the complex situation of flying material movement caused by high magnetic permeability, ensure that the flying material is effectively controlled, and improve the quality of blind hole processing. The processed radar circuit board can better meet the requirements of electrical performance and signal transmission. The above method improves the accuracy of the analysis process of the laser blind hole forming process of the radar circuit board, and then selects an effective auxiliary method to improve the quality of the processed radar circuit board.

[0019] Furthermore, the present invention can accurately take measures against the key factors affecting the processing quality by comparing the roughness of the inner wall of the blind hole of the radar circuit board after processing with the preset roughness, and combining whether the blind hole depth meets the preset conditions to decide whether to adjust the preset depth or the preset magnetic permeability threshold. When the roughness of the inner wall of the blind hole is greater than the preset roughness, it means that the current processing parameters or conditions are insufficient, resulting in poor surface quality. If the blind hole depth meets the preset depth condition, the preset depth can be adjusted to directly change the target depth setting of the blind hole in subsequent processing, avoiding the problem of excessive roughness caused by depth-related factors (such as excessive depth leading to heat accumulation, increased flying materials and thus affecting roughness, etc.) from the source, which helps to make the inner wall of the blind hole processed later smoother and improve the overall processing quality. When the blind hole depth does not meet the preset depth condition, it means that flying materials have fallen into the unprocessed area in the laser scanning path, causing the blind hole depth to not meet the preset depth condition. At this time, adjusting the preset magnetic permeability threshold can change the parameter basis of related effects such as electric field in gas-assisted processing, better control the influence of flying materials and electromagnetic fields in the processing process, reduce the situation where flying materials cannot completely leave the unprocessed area, achieve effective improvement of blind hole processing quality, and ensure that the performance of the radar circuit board is not affected by the rough blind hole surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a workflow diagram of a radar circuit board product processing method based on laser blind via design according to an embodiment of the present invention; Figure 2 A flowchart for determining a blind hole processing environment in a radar circuit board product processing method based on laser blind hole design according to an embodiment of the present invention; Figure 3 The present invention is a flowchart for determining whether to adjust a preset depth and a preset magnetic permeability threshold in a radar circuit board product processing method based on a laser blind via design according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0023] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0024] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] See also Figure 1-Figure 3 As shown, Figure 1 This is a workflow diagram of a radar circuit board product processing method based on laser blind via design according to an embodiment of the present invention; Figure 2 A flowchart for determining a blind hole processing environment in a radar circuit board product processing method based on laser blind hole design according to an embodiment of the present invention; Figure 3 The present invention is a flowchart for determining whether to adjust a preset depth and a preset magnetic permeability threshold in a radar circuit board product processing method based on a laser blind via design according to an embodiment of the present invention.

[0026] The radar circuit board product processing method based on the laser blind hole design in the embodiment of the present invention includes: Step S1, obtaining blind hole processing data, laser working data and radar circuit board data to be processed of the radar circuit board to be processed; Step S2, determining whether the laser blind hole processing environment is an air environment or an oxygen-free environment based on whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed; Step S3, based on the blind hole depth of the radar circuit board to be processed and the laser blind hole processing environment, determine whether to add a flying material shielding device when performing laser blind hole processing, or whether to use a gas-assisted processing method; Step S4, when using the gas-assisted processing method, based on the magnetic permeability of the area not subjected to laser blind hole processing and the thermal diffusion coefficient of the blind hole material to be processed, determining whether to perform gas-assisted processing by a gas temperature adjustment method or an electric field-assisted method; Step S5, determining whether to adjust the preset depth and the preset magnetic permeability threshold according to whether there is a blind hole inner wall with a roughness greater than a preset roughness on the radar circuit board after processing using the gas-assisted processing method and whether the blind hole depth with a roughness greater than the preset roughness meets the preset blind hole depth condition.

[0027] The blind hole processing data in the embodiment of the present invention includes but is not limited to "blind hole depth data, blind hole roughness data and blind hole position data", the laser working data includes but is not limited to "laser working power data, laser wavelength data and laser scanning path data", and the radar circuit board data to be processed includes but is not limited to "radar circuit board material data, thermal characteristic parameter data of the materials contained in the radar circuit board and electrical characteristic parameter data of the materials contained in the radar circuit board".

[0028] Specifically, in step S2, when it is determined that the laser blind hole processing environment is an air environment or an oxygen-free environment, it is determined that the laser blind hole processing environment is an air environment or an oxygen-free environment according to whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed; When there are easily oxidizable materials in the laser scanning path of the radar circuit board to be processed, the laser blind hole processing environment is determined to be an oxygen-free environment; When there is no easily oxidizable material in the laser scanning path of the radar circuit board to be processed, it is determined that the laser blind hole processing environment is an air environment.

[0029] The oxygen-free environment described in the embodiment of the present invention includes but is not limited to "nitrogen environment, argon environment and helium environment". Whether there are easily oxidized materials in the laser scanning path of the radar circuit board to be processed can be determined by checking the detailed design drawings of the radar circuit board and the corresponding material list to see whether there are easily oxidized metal elements such as copper, iron and nickel, and then determining whether there are easily oxidized materials in the laser scanning path of the radar circuit board to be processed.

[0030] The present invention can effectively prevent easily oxidized metal elements such as copper, iron, and nickel from chemically reacting with oxygen during laser processing by carefully judging whether there are easily oxidized materials in the laser scanning path, and then selectively selecting an air environment or an oxygen-free environment for processing. For example, if copper is in an air environment under the action of a high-temperature laser, copper oxide is easily generated, which will change the original electrical and mechanical properties of the material, reduce the conductivity of the circuit board, and increase the surface roughness. However, by using a suitable oxygen-free environment (such as a nitrogen environment, an argon environment, or a helium environment) for processing, such oxidation phenomena can be avoided, ensuring that the inner wall material of the processed blind hole has stable performance, maintaining good electrical connectivity, and improving the overall signal transmission quality and performance of the radar circuit board. For some radar circuit boards with high precision requirements, a tiny oxide layer may cause problems such as increased signal loss or signal interference. Accurately selecting the processing environment can minimize the quality risks caused by oxidation, ensure that the blind hole dimensional accuracy, roughness, and other indicators meet high standards, and help produce high-quality and high-performance radar circuit board products.

[0031] Specifically, in step S3, when a flying material shielding device is added under the condition of laser blind hole processing, or a gas-assisted processing method is used, it is determined whether to add a flying material shielding device or a gas-assisted processing method according to the blind hole depth of the radar circuit board to be processed and the laser blind hole processing environment; When the blind hole depth of the radar circuit board to be processed is less than the preset depth, it is determined that there is no need to add a flying material shielding device and there is no need to use a gas-assisted processing method; When the blind hole depth of the radar circuit board to be processed is greater than or equal to the preset depth and the laser blind hole processing environment is an air environment, it is determined to add a flying material shielding device; When the blind hole depth of the radar circuit board to be processed is greater than or equal to the preset depth and the laser blind hole processing environment is an oxygen-free environment, it is determined to use the gas-assisted processing method.

[0032] The preset depth in the embodiment of the present invention is the average value of the blind hole depths of several radar circuit boards to be processed, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0033] The flying material shielding device described in the embodiment of the present invention includes but is not limited to "adjustable angle plastic baffle, fixed metal baffle and magnetic adsorption plate". For example, a fixed metal baffle is selected as the flying material shielding device, and a stainless steel fixed metal baffle with a thickness of 3mm is installed on the side where the laser processing head moves along the blind hole processing direction. The baffle height is 10cm and the length is 30cm, which can cover the processing range of multiple blind holes. The laser processing parameters are adjusted to laser power 12W, laser scanning speed 15mm / s, laser pulse width 20ns, and focused spot size 60μm. During the processing, flying materials (such as metal chips, etc.) splashed out of the blind hole will fall back into the collection tank near the processing area after hitting the metal baffle, so as to prevent flying materials from splashing onto other unprocessed areas or equipment, thereby ensuring the cleanliness of the processing environment and the processing accuracy of other areas.

[0034] The present invention determines that there is no need to add a flying material shielding device and no need to use a gas-assisted processing method when the blind hole depth is less than a preset depth. This is because a shallower blind hole generates relatively less flying materials during processing, and the impact on the processing quality and environment is limited. At this time, no additional devices and auxiliary processing methods are used. Only when the blind hole depth reaches a certain level (greater than or equal to the preset depth) and meets the corresponding processing environment conditions, a flying material shielding device or a gas-assisted processing method is added. This reasonably allocates resources and reduces the overall processing cost. When the blind hole depth is greater than or equal to the preset depth and the laser blind hole processing environment is an air environment, a flying material shielding device is added. A deeper blind hole is prone to generate more flying materials during processing, and in an air environment, flying materials are more likely to splash around and re-deposit, affecting the processing quality. At this time, a flying material shielding device is used to effectively block the disordered diffusion of flying materials so that they do not affect other Unprocessed areas or processed parts reduce the adverse effects of flying materials on key quality indicators such as blind hole dimensional accuracy and inner wall roughness, ensure that the processed blind holes meet the design requirements, and improve the overall quality and reliability of the product. When the blind hole depth is greater than or equal to the preset depth and the laser blind hole processing environment is an oxygen-free environment, a gas-assisted processing method is used. The oxygen-free environment is usually a special environment created to avoid oxidation of easily oxidizable materials. If deeper blind holes are processed in this environment only by conventional methods, heat accumulation and poor flying material control are prone to problems. The gas-assisted processing method can blow away heat and guide flying materials through gas, improve heat transfer and flying material movement during processing, and help improve the quality of blind hole processing, such as making the inner wall of the blind hole smoother and the size more accurate, to ensure that the signal transmission and other performance of the radar circuit board in subsequent use are not affected by processing quality problems.

[0035] Specifically, in step S4, when it is determined that the gas-assisted processing is performed by the gas temperature adjustment method or the electric field-assisted method, it is determined that the gas-assisted processing is performed by the gas temperature adjustment method or the electric field-assisted method according to the magnetic permeability of the area where the laser blind hole processing is not performed and the thermal diffusion coefficient of the blind hole material to be processed; When the thermal diffusion coefficient of the blind hole material to be processed is less than the preset thermal diffusion coefficient and the magnetic permeability of the area not subjected to laser blind hole processing is less than or equal to the preset magnetic permeability threshold, it is determined to adopt the gas temperature adjustment method for gas-assisted processing; When the thermal diffusion coefficient of the blind hole material to be processed is less than the preset thermal diffusion coefficient and the magnetic permeability of the area not subjected to laser blind hole processing is greater than the preset magnetic permeability threshold, it is determined to adopt the gas temperature adjustment method and the electric field auxiliary method for gas-assisted processing; When the thermal diffusion coefficient of the blind hole material to be processed is greater than or equal to the preset thermal diffusion coefficient, it is determined to adopt the electric field assisted method for gas assisted processing.

[0036] In the embodiment of the present invention, the preset thermal diffusion coefficient is the minimum thermal diffusion coefficient when the roughness of the blind hole of the radar circuit board is less than the preset roughness after the gas temperature adjustment method is not used, and the preset magnetic permeability threshold is the maximum magnetic permeability when the roughness of the blind hole of the radar circuit board is less than the preset roughness after the electric field assisted method is not used, but the above values ​​are not limited to this, and those skilled in the art can also adjust the values ​​according to actual needs.

[0037] In the embodiments of the present invention, when performing gas-assisted processing, no matter whether the gas temperature adjustment method, the electric field assisted method, or the gas temperature adjustment method and the electric field assisted method are selected for gas-assisted processing, there is a process of using gas to blow away flying materials. For example, when gas-assisted processing is performed by the electric field assisted method, the electric field strength is preliminarily estimated based on the electrical properties of the blind hole material to be processed (such as electrical conductivity, dielectric constant, etc.) and the geometric dimensions of the blind hole (such as blind hole diameter and depth). For example, for materials with relatively low electrical conductivity, in order to enable the flying materials to obtain sufficient electric field force to change their movement trajectory under the action of the electric field, it is often necessary to set a higher electric field strength. Some empirical formulas or finite element simulation software can be used to perform simulation calculations to determine an approximate initial electric field strength value. It is assumed that through simulation calculations combined with material property analysis, it is concluded that for a certain blind hole material and size, it is more appropriate to set the initial electric field strength to 500 V / m. The determination of the electric field frequency must be compatible with the laser pulse frequency. Generally speaking, the electric field frequency will be selected based on factors such as the laser pulse frequency and the dielectric properties of the blind hole material. Inert gases such as argon or nitrogen are selected. Argon has extremely stable chemical properties and is not easy to react chemically with materials. It also has good thermal stability. Under the action of the electric field, it will not interfere with the electric field distribution and the movement of flying materials due to problems such as the ionization of the gas itself. Nitrogen has a wide range of sources and low costs, and can also play a role in stabilizing the processing environment and taking away flying materials in auxiliary processing.

[0038] The present invention takes into account the thermal diffusion coefficient, a key parameter reflecting the thermophysical properties of the material, and adopts different gas-assisted processing strategies for materials with different thermal diffusion coefficients. For materials with a small thermal diffusion coefficient, the heat is easily accumulated during the processing. If it is not specifically regulated, it is easy to cause local overheating of the inner wall of the blind hole, causing excessive melting and vaporization of the material, thereby causing quality problems such as increased roughness of the inner wall of the blind hole and decreased dimensional accuracy. When the gas temperature regulation method is used according to the thermal diffusion coefficient or combined with the electric field assisted method, the heat distribution in the processing area can be effectively adjusted. For example, the gas temperature regulation can remove the heat. Excess heat can be eliminated by using electric field to guide the flying materials to avoid bad deposition due to overheating, thereby improving the quality indicators such as dimensional accuracy and inner wall roughness of blind hole processing, and ensuring that the processed blind holes meet the requirements of high-quality radar circuit boards. For materials with large thermal diffusion coefficients, the heat dissipation is relatively fast. The use of electric field-assisted method for gas-assisted processing can better utilize the guiding effect of the electric field on the flying materials, so that the flying materials move in the desired direction, avoid their disordered accumulation affecting the quality of the blind holes, ensure the consistency and accuracy of blind hole processing, and improve the overall processing quality. The magnetic permeability of the area not processed by laser blind holes is also an important factor affecting the behavior of flying materials. The magnetic permeability is an important factor. When the magnetic permeability is less than or equal to the preset magnetic permeability threshold, it means that the response characteristics of the material to the electromagnetic field are in a specific range. The gas temperature adjustment method is used for gas-assisted processing. Under this magnetic permeability condition, the temperature adjustment function of the gas can be used to effectively control heat and flying materials without being disturbed by complex electromagnetic fields, making the processing process more stable, which is helpful to improve the quality stability of blind hole processing and reduce the quality defects caused by abnormal movement and deposition of flying materials due to magnetic permeability-related factors. When the magnetic permeability is greater than the preset magnetic permeability threshold, the behavior of the material in the electromagnetic field changes greatly, and the flying materials are more significantly affected by the magnetic field. At this time, the gas temperature adjustment method is combined with the electric field auxiliary method for gas-assisted processing, which can comprehensively utilize the advantages of gas temperature adjustment to improve the thermal environment and electric field to accurately guide flying materials, better cope with the complex situation of flying material movement caused by high magnetic permeability, ensure that flying materials are effectively controlled, improve the quality of blind hole processing, and make the processed radar circuit board better meet the requirements of electrical performance and signal transmission. The above method improves the accuracy of the analysis process of the radar circuit board laser blind hole forming process, and then selects an effective auxiliary method to improve the quality of the processed radar circuit board.

[0039] Specifically, in step S5, when determining whether to adjust the preset depth and the preset magnetic permeability threshold, it is determined whether to adjust the preset depth and the preset magnetic permeability threshold according to whether there is a blind hole inner wall with a roughness greater than the preset roughness on the radar circuit board after being processed by the gas-assisted processing method and whether the blind hole depth with a roughness greater than the preset roughness meets the preset blind hole depth condition; When the radar circuit board has a blind hole inner wall with a roughness greater than a preset roughness after being processed by the gas-assisted processing method and the blind hole depth with a roughness greater than the preset roughness meets the preset blind hole depth condition, determining to adjust the preset depth; When the radar circuit board after being processed by the gas-assisted processing method has a blind hole inner wall with a roughness greater than a preset roughness and the blind hole depth with a roughness greater than the preset roughness does not meet the preset blind hole depth condition, determining to adjust the preset magnetic permeability threshold; When there is no blind hole inner wall with a roughness greater than a preset roughness on the radar circuit board after processing using the gas-assisted processing method, it is determined that there is no need to adjust the preset depth and the preset magnetic permeability threshold.

[0040] The preset roughness in the embodiment of the present invention is the historical average roughness of the blind holes of the radar circuit board of the same model after processing using the gas-assisted processing method, but the above value is not limited to this, and technicians in this field can also adjust the value according to actual needs.

[0041] Specifically, in step S5, when it is determined to adjust the preset depth, the preset depth is adjusted with a first adjustment coefficient, and when it is determined to adjust the preset magnetic permeability threshold, the preset magnetic permeability threshold is adjusted with a second adjustment coefficient.

[0042] In the embodiment of the present invention, the value range of the first adjustment coefficient is set to 0.82-0.96, and the value of the first adjustment coefficient is preferably 0.88. The value range of the second adjustment coefficient is set to 0.79-0.94, and the value of the second adjustment coefficient is preferably 0.86. The adjustment amount of the preset depth is negatively correlated with the roughness of the blind hole of the radar circuit board after processing using the gas-assisted processing method, and the adjustment amount of the preset magnetic permeability threshold is positively correlated with the depth of the blind hole whose roughness is greater than the preset roughness, but the above values ​​are not limited thereto, and those skilled in the art may also adjust the values ​​according to actual needs.

[0043] In the embodiment of the present invention, determining that the blind hole depth having a roughness greater than a preset roughness meets the preset blind hole depth condition includes that the absolute value of the difference between the blind hole depth and the preset blind hole depth is less than the preset difference, the preset blind hole depth is the required processing depth of the blind hole, and the preset difference is one fiftieth of the blind hole depth, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0044] The present invention compares the roughness of the inner wall of the blind hole of the radar circuit board after processing with the preset roughness, and determines whether to adjust the preset depth or the preset magnetic permeability threshold in combination with whether the blind hole depth meets the preset conditions, and can accurately take measures for the key factors affecting the processing quality. When the roughness of the inner wall of the blind hole is greater than the preset roughness, it means that the current processing parameters or conditions are insufficient, resulting in poor surface quality. If the blind hole depth meets the preset depth condition, the preset depth can be adjusted to directly change the target depth setting of the blind hole in subsequent processing, avoiding the problem of excessive roughness caused by depth-related factors (such as excessive depth leading to heat accumulation, increased flying materials and thus affecting roughness, etc.) from the source, which helps to make the inner wall of the blind hole processed later smoother and improve the overall processing quality. When the blind hole depth does not meet the preset depth condition, it means that flying materials have fallen into the unprocessed area in the laser scanning path, causing the blind hole depth to not meet the preset depth condition. At this time, adjusting the preset magnetic permeability threshold can change the parameter basis of related effects such as electric field in gas-assisted processing, better control the influence of flying materials and electromagnetic fields in the processing process, reduce the situation where flying materials cannot completely leave the unprocessed area, achieve effective improvement of blind hole processing quality, and ensure that the performance of the radar circuit board is not affected by the rough blind hole surface.

[0045] Specifically, in step S4, the determination of adopting the gas temperature adjustment method for gas-assisted processing includes determining the gas temperature according to the thermal diffusion coefficient of the blind hole material and the laser working power.

[0046] In the embodiment of the present invention, the gas temperature is determined according to the thermal diffusion coefficient of the blind hole material and the laser working power, including but not limited to "based on the thermal diffusion coefficient, the basic temperature range is 30℃-50℃ higher than the ambient temperature and based on the laser power, the temperature is increased by 2℃-4℃ if it exceeds 2W". For example, assuming that the current processing environment temperature is 25℃, the thermal diffusion coefficient of the blind hole material to be processed belongs to a relatively small range after detection. According to the rule of "based on the thermal diffusion coefficient, the basic temperature range is 30℃-50℃ higher than the ambient temperature", the basic temperature range is preliminarily determined to be 30℃-50℃ higher than 25℃, that is, 55℃-75℃. At the same time, the laser working power set for the laser equipment selected for this processing is 10W, and the power reference value determined through preliminary tests and process settings is 8W, which exceeds 2W. According to the rule of "based on the laser power, the temperature is increased by 2℃-4℃ if it exceeds 2W", it is necessary to increase the basic temperature range by 2℃-4℃. In summary, the gas temperature range finally determined is 57℃-79℃. A suitable value can be selected within this temperature range, such as 65°C, and the gas can be heated to this temperature for gas-assisted processing, so that it blows through the blind hole processing area, takes away heat and assists the processing process.

[0047] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A radar circuit board product processing method based on laser blind hole design, characterized in that: include: Obtain blind hole processing data, laser working data and radar circuit board data to be processed; Determine whether the laser blind hole processing environment is an air environment or an oxygen-free environment based on whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed; Based on the blind hole depth of the radar circuit board to be processed and the laser blind hole processing environment, determine whether to add a flying material shielding device when performing laser blind hole processing, or whether to use a gas-assisted processing method; When the gas-assisted processing method is used, the gas-assisted processing is determined to be performed by the gas temperature adjustment method or the electric field-assisted method based on the magnetic permeability of the area not subjected to the laser blind hole processing and the thermal diffusion coefficient of the blind hole material to be processed; According to whether there is a blind hole inner wall with a roughness greater than a preset roughness and whether the blind hole depth with a roughness greater than a preset roughness meets the preset blind hole depth condition after being processed by the gas-assisted processing method, it is determined whether to adjust the preset depth and the preset magnetic permeability threshold.

2. The radar circuit board product processing method based on laser blind hole design according to claim 1 is characterized in that: Determining whether the laser blind hole processing environment is an air environment or an oxygen-free environment includes: If there are easily oxidizable materials in the laser scanning path of the radar circuit board to be processed, make sure that the laser blind hole processing environment is an oxygen-free environment; If there is no easily oxidizable material in the laser scanning path of the radar circuit board to be processed, it is determined that the laser blind hole processing environment is an air environment.

3. The radar circuit board product processing method based on laser blind hole design according to claim 2 is characterized in that: Whether to add a flying material shielding device during laser blind hole processing, or whether to use a gas-assisted processing method includes: If the blind hole depth of the radar circuit board to be processed is less than the preset depth, it is determined that there is no need to add a flying material shielding device and there is no need to use a gas-assisted processing method; If the blind hole depth of the radar circuit board to be processed is greater than or equal to the preset depth and the laser blind hole processing environment is an air environment, it is determined to add a flying material shielding device; If the blind hole depth of the radar circuit board to be processed is greater than or equal to the preset depth and the laser blind hole processing environment is an oxygen-free environment, it is determined to use the gas-assisted processing method.

4. The radar circuit board product processing method based on laser blind hole design according to claim 3 is characterized in that: The preset depth is determined according to an average value of blind hole depths of a plurality of radar circuit boards to be processed.

5. The radar circuit board product processing method based on laser blind hole design according to claim 4 is characterized in that: The method of determining to perform gas-assisted processing by a gas temperature adjustment method or an electric field assisted method comprises: If the thermal diffusion coefficient of the blind hole material to be processed is less than the preset thermal diffusion coefficient and the magnetic permeability of the area not subjected to laser blind hole processing is less than or equal to the preset magnetic permeability threshold, it is determined to adopt the gas temperature adjustment method for gas-assisted processing; If the thermal diffusion coefficient of the blind hole material to be processed is less than the preset thermal diffusion coefficient and the magnetic permeability of the area not subjected to laser blind hole processing is greater than the preset magnetic permeability threshold, it is determined to use the gas temperature adjustment method and the electric field auxiliary method for gas-assisted processing; If the thermal diffusion coefficient of the blind hole material to be processed is greater than or equal to the preset thermal diffusion coefficient, it is determined to use the electric field assisted method for gas assisted processing.

6. The radar circuit board product processing method based on laser blind hole design according to claim 5 is characterized in that: The determining whether to adjust the preset depth and the preset magnetic permeability threshold comprises: If the radar circuit board has a blind hole inner wall with a roughness greater than a preset roughness after being processed by the gas-assisted processing method and the blind hole depth with a roughness greater than the preset roughness meets the preset blind hole depth condition, it is determined to adjust the preset depth; If, after being processed by the gas-assisted processing method, the radar circuit board has a blind hole inner wall with a roughness greater than a preset roughness and the blind hole depth with a roughness greater than the preset roughness does not meet the preset blind hole depth condition, it is determined to adjust the preset magnetic permeability threshold.

7. The radar circuit board product processing method based on laser blind hole design according to claim 6 is characterized in that: The preset roughness is determined according to the historical average roughness of blind holes of radar circuit boards of the same model processed by the gas-assisted processing method.

8. The radar circuit board product processing method based on laser blind hole design according to claim 7 is characterized in that: The adjustment amount of the preset depth is negatively correlated with the roughness of the blind hole of the radar circuit board after processing using the gas-assisted processing method, and the adjustment amount of the preset magnetic permeability threshold is positively correlated with the depth of the blind hole whose roughness is greater than the preset roughness.

9. The radar circuit board product processing method based on laser blind hole design according to claim 8 is characterized in that: Determining that the blind hole depth having a roughness greater than a preset roughness meets a preset blind hole depth condition includes that an absolute value of a difference between the blind hole depth and the preset blind hole depth is less than a preset difference, and the preset blind hole depth is a required processing depth of the blind hole.

10. The radar circuit board product processing method based on laser blind hole design according to claim 4 is characterized in that: The determination of using the gas temperature adjustment method for gas-assisted processing includes determining the gas temperature according to the thermal diffusion coefficient of the blind hole material and the laser working power.

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