A processing method for a radar circuit board product based on laser blind hole design

Abstract

The present invention relates to the technical field of circuit board processing, and in particular to a processing method for a radar circuit board product based on laser blind hole design. The method includes determining the laser blind hole processing environment based on whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed; determining whether to add a flying material shielding device and / or whether to use a gas-assisted processing method during laser blind hole processing based on the blind hole depth of the radar circuit board to be processed and the laser blind hole processing environment; when using the gas-assisted processing method, determining the gas-assisted processing method based on the magnetic permeability of the area where laser blind hole processing has not been performed and the thermal diffusion coefficient of the material of the blind hole to be processed; determining whether to adjust the processing process according to the roughness and blind hole depth of the blind holes of the radar circuit board after processing using the gas-assisted processing method. The present invention improves the processing accuracy of laser blind holes and the processing quality of blind holes by adding an auxiliary method to the laser blind hole processing process.

Description

Technical Field

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

[0002] With the rapid development of radar technology, as a key component of the radar system, the performance requirements for radar printed circuit boards are getting higher and higher. Radar printed circuit boards usually require high integration and miniaturization. Blind holes are important structures for realizing electrical connections between multiple layers of printed circuit boards. Laser blind hole processing technology has been widely used in the manufacture of radar printed circuit boards due to its advantages such as high precision and high flexibility. However, during the laser blind hole processing, many technical challenges are faced. In traditional processing, the control means for flying materials (such as material debris generated during processing) are relatively single. When the depth of the blind hole reaches a certain level, the problem of flying materials will become more prominent. When performing deep blind hole processing in an air environment, if only relying on simple processing methods, the flying materials may redeposit on the surface of the blind hole or the printed circuit board, affecting the dimensional accuracy and surface quality of the blind hole.

[0003] Chinese Patent Application Publication No.: CN106793572A discloses a drilling method for forming blind holes by laser on a multi-layer printed circuit board. The drilling method for forming blind holes by laser on the multi-layer printed circuit board includes the following steps: micro-etching the surface copper to be processed on the multi-layer printed circuit board to micro-etch away part of the copper layer and retain the surface copper with a set thickness; performing brownification treatment on the retained surface copper with a set thickness and oxidizing the surface copper to black to form a transition layer; using a CO2 laser to perform laser drilling treatment at a specified position on the transition layer of the multi-layer printed circuit board to form blind holes. The technical solution of this invention can improve the ability to make the aspect ratio of the blind hole. After testing, when the aspect ratio of the blind hole reaches 1.4:1, no blind hole cavity or crack problems will occur, thus improving the hole-forming effect of the blind hole.

[0004] It can be seen that the existing technology has the problem that the analysis of the process of forming blind holes by laser on radar printed circuit boards is not accurate enough, resulting in the inability to select effective auxiliary methods and causing low quality of the processed blind holes. Summary of the Invention

[0005] Therefore, the present invention provides a processing method for a radar printed circuit board product based on laser blind hole design to overcome the problem in the existing technology that the analysis of the process of forming blind holes by laser on radar printed circuit boards 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 processing method for a radar printed circuit board product based on laser blind hole design, including:

[0007] Obtaining the blind hole processing data, laser working data, and the data of the radar printed circuit board to be processed;

[0008] Determine whether the laser blind hole machining environment is an air environment or an anaerobic environment based on whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be machined;

[0009] Based on the blind hole depth of the radar circuit board to be machined and the laser blind hole machining environment, determine whether to add a flying material shielding device and / or whether to use a gas-assisted machining method during laser blind hole machining;

[0010] When using the gas-assisted machining method, based on the magnetic permeability of the area where laser blind hole machining has not been performed and the thermal diffusion coefficient of the material of the blind hole to be machined, determine to perform gas-assisted machining by means of gas temperature regulation method and / or by means of electric field assistance;

[0011] According to whether there is a blind hole inner wall with a roughness greater than the preset roughness and whether the blind hole depth with a roughness greater than the preset roughness meets the preset blind hole depth condition after machining the radar circuit board using the gas-assisted machining method, determine whether to adjust the preset depth and the preset magnetic permeability threshold;

[0012] Determining that the laser blind hole machining environment is an air environment or an anaerobic environment includes:

[0013] If there is an easily oxidizable material in the laser scanning path of the radar circuit board to be machined, determine that the laser blind hole machining environment is an anaerobic environment;

[0014] If there is no easily oxidizable material in the laser scanning path of the radar circuit board to be machined, determine that the laser blind hole machining environment is an air environment;

[0015] Whether to add a flying material shielding device and / or whether to use a gas-assisted machining method during laser blind hole machining includes:

[0016] If the blind hole depth of the radar circuit board to be machined is less than the preset depth, determine that there is no need to add a flying material shielding device and no need to use a gas-assisted machining method;

[0017] If the blind hole depth of the radar circuit board to be machined is greater than or equal to the preset depth and the laser blind hole machining environment is an air environment, determine to add a flying material shielding device;

[0018] If the blind hole depth of the radar circuit board to be machined is greater than or equal to the preset depth and the laser blind hole machining environment is an anaerobic environment, determine to use a gas-assisted machining method;

[0019] The determination of whether to adjust the preset depth and the preset magnetic permeability threshold includes:

[0020] If, after processing using a gas-assisted processing method, the inner wall of a blind hole on a radar circuit board has a roughness greater than a preset roughness and the depth of the blind hole with a roughness greater than the preset roughness meets the preset blind hole depth condition, determine to adjust the preset depth;

[0021] If, after processing using a gas-assisted processing method, the inner wall of a blind hole on a radar circuit board has a roughness greater than a preset roughness and the depth of the blind hole with a roughness greater than the preset roughness does not meet the preset blind hole depth condition, determine to adjust the preset magnetic permeability threshold.

[0022] Further, the preset depth is determined according to the average value of the blind hole depths of several radar circuit boards to be processed.

[0023] Further, the determination to perform gas-assisted processing using a gas temperature regulation method and / or an electric field assistance method includes:

[0024] If the thermal diffusivity of the material of the blind hole to be processed is less than a preset thermal diffusivity and the magnetic permeability of the area where laser blind hole processing has not been performed is less than or equal to a preset magnetic permeability threshold, determine to perform gas-assisted processing using a gas temperature regulation method;

[0025] If the thermal diffusivity of the material of the blind hole to be processed is less than a preset thermal diffusivity and the magnetic permeability of the area where laser blind hole processing has not been performed is greater than the preset magnetic permeability threshold, determine to perform gas-assisted processing using a gas temperature regulation method and an electric field assistance method;

[0026] If the thermal diffusivity of the material of the blind hole to be processed is greater than or equal to the preset thermal diffusivity, determine to perform gas-assisted processing using an electric field assistance method.

[0027] Further, the preset roughness is determined according to the historical average value of the roughness of the blind holes of the same type of radar circuit board after processing using a gas-assisted processing method.

[0028] Further, the adjustment amount of the preset depth is negatively correlated with the roughness of the blind holes on the radar circuit board after processing using a gas-assisted processing method, and the adjustment amount of the preset magnetic permeability threshold is positively correlated with the depth of the blind holes with a roughness greater than the preset roughness.

[0029] Further, determining that the depth of the blind hole with a roughness greater than the 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 a preset difference, and the preset blind hole depth is the required processing depth of the blind hole.

[0030] Further, the determination to perform gas-assisted processing using a gas temperature regulation method includes determining the gas temperature according to the thermal diffusivity of the blind hole material and the laser working power.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows. By carefully judging whether there are easily oxidizable materials in the laser scanning path and then selectively choosing an air environment or an oxygen-free environment for processing, the present invention can effectively prevent easily oxidizable metal elements such as copper, iron, nickel, etc. from undergoing chemical reactions with oxygen during the laser processing. For example, when copper is under the action of high-temperature laser in an air environment, it is easy to generate copper oxide, which will change the original electrical and mechanical properties of the material, resulting in a decrease in the conductivity of the circuit board and an increase in 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 the stable material properties of the inner wall of the processed blind hole, maintaining good electrical connectivity, and improving the overall signal transmission quality and service performance of the radar circuit board. For some radar circuit boards with high-precision requirements, even a tiny oxide layer may cause problems such as increased signal loss or signal interference. Precise selection of the processing environment can minimize the quality risks caused by oxidation to the greatest extent, ensure that indicators such as the size accuracy and roughness of the blind hole meet high-standard requirements, and contribute to the production of high-quality and high-performance radar circuit board products.

[0032] Furthermore, for the case where the depth of the blind hole is less than the preset depth, 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. This is because relatively less flying material is generated during the processing of shallower blind holes, and the impact on the processing quality and the environment is limited. At this time, without using additional devices and auxiliary processing methods, only when the depth of the blind hole 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. In this way, resources are reasonably allocated and the overall processing cost is reduced. 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 air environment, a flying material shielding device is added. Deeper blind holes are prone to generating more flying material during the processing, and in an air environment, the flying material is more likely to splash around and redeposit, affecting the processing quality. At this time, using a flying material shielding device can effectively block the disorderly diffusion of the flying material, preventing it from affecting other unprocessed areas or the already processed parts, reducing the adverse effects of the flying material on key quality indicators such as the dimensional accuracy and inner wall roughness of the blind hole, ensuring that the processed blind hole meets the design requirements, and improving the overall quality and reliability of the product. 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 anaerobic environment, a gas-assisted processing method is used. The anaerobic environment is usually a special environment created to avoid the oxidation of easily oxidizable materials. If only relying on conventional methods during the processing of deeper blind holes in this environment, problems such as heat accumulation and poor flying material control are likely to occur. The gas-assisted processing method can blow away heat and guide the flying material through the blowing of gas, improving the heat transfer situation and the flying material movement situation during the processing, which helps to improve the quality of blind hole processing, such as making the inner wall of the blind hole smoother and the dimensions more accurate, and ensuring that the performance such as signal transmission of the radar circuit board during subsequent use is not interfered by processing quality problems.

[0033] 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.

[0034] 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

[0035] 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;

[0036] 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;

[0037] 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

[0038] 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.

[0039] 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.

[0040] It should be noted that in the description of the present invention, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for 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, and therefore should not be construed as a limitation of the present invention.

[0041] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] Please refer to Figures 1 - 3 as shown Figure 1 which is the working flowchart of the processing method of the radar circuit board product based on the laser blind hole design in the embodiment of the present invention; Figure 2 which is the working flowchart of determining the blind hole processing environment in the processing method of the radar circuit board product based on the laser blind hole design in the embodiment of the present invention; Figure 3 which is the working flowchart of determining whether to adjust the preset depth and the preset magnetic permeability threshold in the processing method of the radar circuit board product based on the laser blind hole design in the embodiment of the present invention.

[0043] The processing method of the radar circuit board product based on the laser blind hole design in the embodiment of the present invention includes:

[0044] Step S1, obtaining the blind hole processing data, laser working data, and the data of the radar circuit board to be processed;

[0045] Step S2, determining whether the laser blind hole processing environment is an air environment or an anaerobic environment based on whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed;

[0046] Step S3, determining whether to add a flying material shielding device and / or whether to use a gas-assisted processing method during laser blind hole processing based on the blind hole depth of the radar circuit board to be processed and the laser blind hole processing environment;

[0047] Step S4, when using the gas-assisted processing method, determining to perform gas-assisted processing by a gas temperature adjustment method and / or an electric field assistance method based on the magnetic permeability of the area where laser blind hole processing has not been performed and the thermal diffusion coefficient of the material of the blind hole to be processed;

[0048] Step S5: Determine whether to adjust the preset depth and the preset magnetic permeability threshold according to whether there is an inner wall of a blind hole with a roughness greater than the preset roughness and whether the depth of the blind hole with a roughness greater than the preset roughness meets the preset blind hole depth condition after processing the radar circuit board using the gas-assisted processing method.

[0049] In the embodiments of the present invention, the blind hole processing data 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".

[0050] Specifically, in step S2, when it is determined that the laser blind hole processing environment is an air environment or an anaerobic environment, determine whether the laser blind hole processing environment is an air environment or an anaerobic environment according to whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed;

[0051] When there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed, determine that the laser blind hole processing environment is an anaerobic environment;

[0052] When there is no easily oxidizable material in the laser scanning path of the radar circuit board to be processed, determine that the laser blind hole processing environment is an air environment.

[0053] In the embodiments of the present invention, the anaerobic environment includes, but is not limited to, "nitrogen environment, argon environment, and helium environment". To determine whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed, it can be judged by checking whether there are easily oxidizable metal elements such as copper, iron, and nickel in the detailed design drawings of the radar circuit board and the corresponding material list, so as to determine whether there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed.

[0054] The present invention can effectively prevent oxidation-reactive metal elements such as copper, iron, and nickel from undergoing chemical reactions with oxygen during laser processing by carefully determining whether there are oxidation-prone materials in the laser scanning path and then selectively choosing an air environment or an oxygen-free environment for processing. For example, when copper is under the action of high-temperature laser in an air environment, it is easy to form copper oxide, which will change the original electrical and mechanical properties of the material, resulting in a decrease in the conductivity of the circuit board and an increase in 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 the stable performance of the material on the inner wall of the drilled blind hole, maintaining good electrical connectivity, and improving the overall signal transmission quality and service performance of the radar circuit board. For some radar circuit boards with high-precision requirements, even a tiny oxide layer may lead to problems such as increased signal loss or signal interference. Accurately selecting the processing environment can minimize the quality risks caused by oxidation, ensure that indicators such as the size accuracy and roughness of the blind hole meet high-standard requirements, and contribute to the production of high-quality and high-performance radar circuit board products.

[0055] Specifically, in step S3, when determining whether to add a flying material shielding device or whether to use a gas-assisted processing method under the conditions of laser blind hole processing, it is determined whether to add a flying material shielding device and / or whether to use 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.

[0056] 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 no need to use a gas-assisted processing method.

[0057] 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.

[0058] 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 a gas-assisted processing method.

[0059] In the embodiment of the present invention, the preset depth is the average value of the blind hole depths of several radar circuit boards to be processed, but the above value is not limited to this, and those skilled in the art can also adjust this value according to actual needs.

[0060] In the embodiment of the present invention, the flying material shielding device 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. A stainless steel fixed metal baffle with a thickness of 3 mm is installed on the side where the laser processing head moves along the processing direction of the blind hole. The height of the baffle is 10 cm and the length is 30 cm, which can cover the processing range of multiple blind holes. The laser processing parameters are adjusted to a laser power of 12 W, a laser scanning speed of 15 mm / s, a laser pulse width of 20 ns, and a focused spot size of 60 μm. During the processing, the flying materials (such as metal chips, etc.) splashed out from the blind hole will fall back into the collection tank near the processing area after hitting the metal baffle, avoiding the flying materials from splashing onto other unprocessed areas or equipment, ensuring the cleanliness of the processing environment and the processing accuracy of other areas.

[0061] For the case where the depth of the blind hole is less than the preset depth in the present invention, it is determined that there is no need to add a flying material shielding device and no need to use the gas-assisted processing method. This is because relatively less flying materials are generated during the processing of shallower blind holes, and the impact on the processing quality and environment is limited. At this time, without using additional devices and auxiliary processing methods, only when the depth of the blind hole reaches a certain level (greater than or equal to the preset depth) and meets the corresponding processing environment conditions, will a flying material shielding device or a gas-assisted processing method be added. In this way, resources are reasonably allocated and the overall processing cost is reduced. 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 air environment, a flying material shielding device is added. Deeper blind holes are more likely to generate more flying materials during the processing, and in an air environment, the flying materials are more likely to splash around and redeposit, affecting the processing quality. At this time, using a flying material shielding device can effectively block the disorderly diffusion of the flying materials, preventing them from affecting other unprocessed areas or the processed parts, reducing the adverse effects of the flying materials on key quality indicators such as the dimensional accuracy and inner wall roughness of the blind hole, ensuring that the processed blind holes meet the design requirements, and improving the overall quality and reliability of the product. 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 anaerobic environment, the gas-assisted processing method is used. The anaerobic environment is usually a special environment created to avoid the oxidation of easily oxidizable materials. If only relying on conventional methods during the processing of deeper blind holes in this environment, problems such as heat accumulation and poor control of flying materials are likely to occur. The gas-assisted processing method can blow away heat and guide flying materials through the gas, improving the heat transfer situation and the movement situation of flying materials during the processing, which helps to improve the quality of blind hole processing, such as making the inner wall of the blind hole smoother and the dimensions more accurate, ensuring that the performance such as signal transmission of the radar circuit board during subsequent use is not interfered by processing quality problems.

[0062] Specifically, in step S4, when it is determined to perform gas-assisted machining by means of gas temperature regulation method or electric field assistance method, the gas-assisted machining is determined by means of gas temperature regulation method and / or electric field assistance method according to the magnetic permeability of the area where laser blind hole machining has not been performed and the thermal diffusivity of the blind hole material to be machined;

[0063] When the thermal diffusivity of the blind hole material to be machined is less than the preset thermal diffusivity and the magnetic permeability of the area where laser blind hole machining has not been performed is less than or equal to the preset magnetic permeability threshold, it is determined to perform gas-assisted machining by means of gas temperature regulation method;

[0064] When the thermal diffusivity of the blind hole material to be machined is less than the preset thermal diffusivity and the magnetic permeability of the area where laser blind hole machining has not been performed is greater than the preset magnetic permeability threshold, it is determined to perform gas-assisted machining by means of gas temperature regulation method and electric field assistance method;

[0065] When the thermal diffusivity of the blind hole material to be machined is greater than or equal to the preset thermal diffusivity, it is determined to perform gas-assisted machining by means of electric field assistance method.

[0066] In the embodiment of the present invention, the preset thermal diffusivity is the minimum thermal diffusivity when the roughness of the blind hole of the radar circuit board after machining without using the gas temperature regulation method is less than the preset roughness, and the preset magnetic permeability threshold is the maximum magnetic permeability when the roughness of the blind hole of the radar circuit board after machining without using the electric field assistance method is less than the preset roughness. However, the above values are not limited to this, and those skilled in the art can also adjust the values according to actual needs.

[0067] In the embodiments of the present invention, when gas-assisted machining is performed, whether the gas temperature regulation method, the electric field assistance method, or the gas temperature regulation method and the electric field assistance method are selected for gas-assisted machining, there is a process of using gas to blow away the flying materials. For example, when gas-assisted machining is performed by the electric field assistance method, the electric field strength is initially estimated based on the electrical properties (such as conductivity, dielectric constant, etc.) of the blind hole material to be machined and the geometric dimensions of the blind hole (such as blind hole diameter, depth). For example, for materials with relatively low conductivity, in order to enable the flying materials to obtain sufficient electric field force under the action of the electric field to change their movement trajectories, a relatively high electric field strength often needs to be set. Some empirical formulas can be used or simulation calculations can be performed through finite element simulation software to determine a rough initial electric field strength value. Suppose through simulation calculations combined with material property analysis, it is concluded that for a certain specific blind hole material and size, the initial electric field strength is set to be 500 V / m is more appropriate. The determination of the electric field frequency should be adapted to the pulse frequency of the laser. Generally speaking, the electric field frequency will be selected according to factors such as the laser pulse frequency and the dielectric properties of the blind hole material. An inert gas is selected, such as argon or nitrogen. Argon has extremely stable chemical properties, is not easy to react chemically with materials, and has good thermal stability. 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 under the action of the electric field; nitrogen is widely sourced and has a low cost, and can also play a role in stabilizing the machining environment and taking away flying materials during the assisted machining.

[0068] By considering the thermal diffusivity, a key parameter reflecting the thermophysical properties of materials, different gas-assisted processing strategies are adopted for materials with different thermal diffusivities. For materials with a small thermal diffusivity, heat is likely to accumulate during the processing. Without targeted regulation, it is easy to cause local overheating on the inner wall of the blind hole, leading to excessive melting and vaporization of the materials, and further resulting in quality problems such as an increase in the inner wall roughness of the blind hole and a decrease in dimensional accuracy. When the gas temperature regulation method or a combination with the electric field-assisted method is used based on the judgment of the thermal diffusivity, the heat distribution in the processing area can be effectively adjusted. For example, the excess heat can be removed by gas temperature regulation, or the flying materials can be guided by the electric field assistance to avoid poor deposition caused by overheating, thereby improving the quality indicators such as the dimensional accuracy and the inner wall roughness of the blind hole processing, ensuring that the processed blind holes meet the requirements of high-quality radar circuit boards. For materials with a large thermal diffusivity, their heat dissipation is relatively fast. When using the electric field-assisted method for gas-assisted processing, the guiding effect of the electric field on the flying materials can be better utilized, enabling the flying materials to move in the desired direction, avoiding their disordered accumulation from affecting the quality of the blind hole, ensuring the consistency and accuracy of the blind hole processing, and improving the overall processing quality. The magnetic permeability of the area without laser blind hole processing is also an important factor affecting the behavior of the flying materials. 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. When using the gas temperature regulation method for gas-assisted processing, under this magnetic permeability condition, the temperature regulation function of the gas can be utilized to effectively control the heat and the flying materials without being interfered by the complex electromagnetic field, making the processing process more stable, helping to improve the quality stability of the blind hole processing, and reducing the quality defects caused by the abnormal movement and deposition of the flying materials due to the 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, when using a combination of the gas temperature regulation method and the electric field-assisted method for gas-assisted processing, the advantages of using the gas to regulate the temperature to improve the thermal environment and the electric field to accurately guide the flying materials can be comprehensively utilized to better cope with the complex situation of the flying material movement caused by the high magnetic permeability, ensure that the flying materials are effectively controlled, improve the quality of the blind hole processing, and enable the processed radar circuit board to better meet the requirements in terms of electrical performance and signal transmission. Through the above methods, the accuracy of the analysis process of the laser blind hole formation process of the radar circuit board is improved, and then an effective auxiliary method is selected to improve the quality of the processed radar circuit board.

[0069] 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 are inner walls of blind holes with a roughness greater than the preset roughness and whether the depth of the blind holes with a roughness greater than the preset roughness meets the preset blind hole depth condition after processing the radar circuit board using the gas-assisted processing method;

[0070] When there is an inner wall of a blind hole with a roughness greater than a preset roughness and the depth of the blind hole with a roughness greater than the preset roughness meets the preset blind hole depth condition after processing the radar circuit board using a gas-assisted processing method, it is determined to adjust the preset depth;

[0071] When there is an inner wall of a blind hole with a roughness greater than a preset roughness and the depth of the blind hole with a roughness greater than the preset roughness does not meet the preset blind hole depth condition after processing the radar circuit board using a gas-assisted processing method, it is determined to adjust the preset magnetic permeability threshold;

[0072] When there is no inner wall of a blind hole with a roughness greater than a preset roughness after processing the radar circuit board using a gas-assisted processing method, it is determined that there is no need to adjust the preset depth and the preset magnetic permeability threshold.

[0073] In the embodiments of the present invention, the preset roughness is the historical average value of the roughness of the blind holes of the radar circuit boards of the same model after processing using a gas-assisted processing method, but the above value is not limited to this, and those skilled in the art can also adjust this value according to actual needs.

[0074] 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.

[0075] In the embodiments of the present invention, the value range of the first adjustment coefficient is set to 0.82 - 0.96, the preferred value of the first adjustment coefficient is 0.88, the value range of the second adjustment coefficient is set to 0.79 - 0.94, the preferred value of the second adjustment coefficient is 0.86, the adjustment amount of the preset depth is negatively correlated with the roughness of the blind holes of the radar circuit board after processing using a gas-assisted processing method, and the adjustment amount of the preset magnetic permeability threshold is positively correlated with the depth of the blind holes with a roughness greater than the preset roughness, but the above values are not limited to this, and those skilled in the art can also adjust this value according to actual needs.

[0076] In the embodiments of the present invention, determining that the depth of the blind hole with a roughness greater than the 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 a 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 values are not limited to this, and those skilled in the art can also adjust this value according to actual needs.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] So far, the technical solution of the present invention has 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.

[0081] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A processing method for a radar circuit board product based on laser blind hole design, characterized in that, Including: Obtaining the blind hole processing data, laser working data, and the data of the radar circuit board to be processed; Determining whether the laser blind hole processing environment is an air environment or an anaerobic 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, determining whether to add a flying material shielding device and / or whether to use a gas-assisted processing method during laser blind hole processing; When using the gas-assisted processing method, determining to perform gas-assisted processing by a gas temperature adjustment method and / or an electric field-assisted method based on the magnetic permeability of the area where laser blind hole processing has not been performed and the thermal diffusion coefficient of the blind hole material to be processed; Determining whether to adjust the preset depth and the preset magnetic permeability threshold according to whether there are blind hole inner walls with roughness greater than the preset roughness and whether the blind hole depth with roughness greater than the preset roughness meets the preset blind hole depth condition after processing the radar circuit board using the gas-assisted processing method; Determining that the laser blind hole processing environment is an air environment or an anaerobic environment includes: If there is an easily oxidizable material in the laser scanning path of the radar circuit board to be processed, determining that the laser blind hole processing environment is an anaerobic environment; If there is no easily oxidizable material in the laser scanning path of the radar circuit board to be processed, determining that the laser blind hole processing environment is an air environment; Whether to add a flying material shielding device and / or whether to use a gas-assisted processing method during laser blind hole processing includes: If the blind hole depth of the radar circuit board to be processed is less than the preset depth, determining that there is no need to add a flying material shielding device and 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, determining 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 anaerobic environment, determining to use a gas-assisted processing method; Determining whether to adjust the preset depth and the preset magnetic permeability threshold includes: If there are blind hole inner walls with roughness greater than the preset roughness and the blind hole depth with roughness greater than the preset roughness meets the preset blind hole depth condition after processing the radar circuit board using the gas-assisted processing method, determining to adjust the preset depth; If there are blind hole inner walls with roughness greater than the preset roughness and the blind hole depth with roughness greater than the preset roughness does not meet the preset blind hole depth condition after processing the radar circuit board using the gas-assisted processing method, determining to adjust the preset magnetic permeability threshold.

2. The processing method of the radar circuit board product based on the laser blind hole design according to claim 1, wherein, The preset depth is determined according to the average value of the blind hole depths of several radar circuit boards to be processed.

3. The processing method of the radar circuit board product based on the laser blind hole design according to claim 2, wherein, Determining to perform gas-assisted processing by a gas temperature adjustment method and / 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 where laser blind hole processing has not been performed is less than or equal to the preset magnetic permeability threshold, determining to use the gas temperature adjustment method for gas-assisted processing; If the thermal diffusivity of the blind hole material to be processed is less than the preset thermal diffusivity and the magnetic permeability of the area where laser blind hole machining is not performed is greater than the preset magnetic permeability threshold, it is determined to use the gas temperature regulation method and the electric field assistance method for gas-assisted machining; If the thermal diffusivity of the blind hole material to be processed is greater than or equal to the preset thermal diffusivity, it is determined to use the electric field assistance method for gas-assisted machining.

4. The processing method of the radar circuit board product designed based on laser blind holes according to claim 3, characterized in that, The preset roughness is determined according to the historical average value of the roughness of the blind holes of the same type of radar circuit board processed by the gas-assisted machining method.

5. The processing method of the radar circuit board product based on the laser blind hole design according to claim 4, wherein, The adjustment amount of the preset depth is negatively correlated with the roughness of the blind holes of the radar circuit board processed by the gas-assisted machining method, and the adjustment amount of the preset magnetic permeability threshold is positively correlated with the depth of the blind holes whose roughness is greater than the preset roughness.

6. The processing method of the radar circuit board product designed based on laser blind holes according to claim 5, characterized in that, Determining that the depth of the blind hole with a roughness greater than the 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, and the preset blind hole depth is the depth to be processed of the blind hole.

7. The processing method of the radar circuit board product based on the laser blind hole design according to claim 3, characterized in that, The determination of using the gas temperature regulation method for gas-assisted machining includes determining the gas temperature according to the thermal diffusivity of the blind hole material and the laser working power.

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