A numerical simulation method and system for the entire lifecycle of a printed circuit board

Abstract

This invention belongs to the field of printed circuit board (PCB) technology and provides a method and system for numerical simulation of the entire life cycle of PCBs. The method includes obtaining the material performance parameters of the PCB and the initial boundary conditions of the manufacturing process; obtaining a model database file containing the numerical simulation output and stored digital information of the PCB manufacturing process based on a finite element model of the PCB manufacturing process; using the digital information stored in the model database file as the initial conditions for numerical simulation of the PCB service process; and adaptively adjusting the mechanical equilibrium at the initial moment of the numerical simulation to achieve the inheritance of multiphysics and the continuation of numerical calculations; after the adaptive adjustment of mechanical equilibrium, numerical simulation of the PCB service conditions is performed based on the finite element model of the PCB service process, ultimately realizing the full-process numerical analysis of the PCB from manufacturing to service, to predict the quality and reliability of the PCB throughout its entire life cycle.

Description

Technical Field

[0001] This invention belongs to the field of printed circuit board technology, and in particular relates to a numerical simulation method and system for the entire life cycle of printed circuit boards. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Printed Circuit Boards (PCBs), as an important component of modern electronic products, play a crucial role in realizing the electrical interconnection between various electronic components and the transmission of digital signals, especially in supporting large-size chips and enabling high-speed signal transmission between chips and circuit boards. By adding metal materials as conductors on an insulating substrate, PCBs reduce the difficulty and cost of implementing complex circuits, thus quickly gaining dominance in the interconnection of electronic components after their emergence. Currently, PCB manufacturing involves processes such as raw material selection, stacking, lamination molding, milling, drilling, hole metallization, electroplating thickening of surface circuit areas, etching of non-circuit areas, solder resist treatment, reflow soldering, surface mount assembly, and electrical performance testing. Afterward, during the PCB's service life, it may face complex environments such as alternating high and low temperatures, electromagnetic radiation, and impacts.

[0004] The raw materials for PCBs include copper foil, prepreg, and copper-clad laminate. The thickness of copper foil is expressed in oz, where 1 oz = 35 μm = 0.035 mm. Prepreg, also known as PP sheet or prepreg, is composed of resin and reinforcing materials; epoxy resin is commonly used as the resin, and electronic-grade fiberglass woven fabric is commonly used as the reinforcing material. During the manufacturing process, the material properties of a PCB change multiple times with time and temperature. Especially during the high-temperature and high-pressure resin softening, flow, and chemical cross-linking curing reactions, the resin fills the voids in the metal pattern while simultaneously experiencing volume shrinkage due to chemical reactions and volume expansion due to heat. This leads to demolding deformation of the PCB after molding. Furthermore, the physical structure of the PCB changes after processes such as drilling, etching, electroplating, and milling, and the release of internal residual stress also causes warping. During reflow soldering, the PCB is affected by non-uniform and unsteady-state temperatures both in-plane and between layers. The non-uniform temperature field and the different thermal expansion coefficients of the dissimilar materials result in varying degrees of thermal deformation, exacerbating PCB warping at high temperatures. Even after reflow soldering and cooling to room temperature, residual internal stress remains on the PCB. PCB warping, also known as twisting and bending, refers to the phenomenon where an originally flat circuit board tilts slightly upwards at both ends or in the middle when placed on a horizontal surface. The IPC standard specifies that the maximum allowable warpage and twist of PCBs is between 0.75% and 1.5%. However, due to differences in the process capabilities of each factory, the control requirements for PCB warpage also vary. Severe PCB warpage will affect the smooth operation of automated surface mount production lines.

[0005] During service, PCBs are subject to temperature cycling or power cycling, which can easily lead to fatigue failure and a reduction in mechanical properties. PCBs are also subjected to various vibrations, shocks, and bending and torsional loads, which increase internal stress and can cause stress concentration and failure at defects. PCBs will age under prolonged conditions of high temperature, oxygen, and humidity, which will also reduce their service life and affect their warping deformation. PCB warping during service may affect the reliability of circuit functions.

[0006] The inventors discovered that currently, exploring the evolution of PCB material properties or stress throughout its entire lifecycle through experiments is extremely time-consuming and labor-intensive. For example, in the study of PCB warpage, measurements using the shading method or digital imaging technology can only obtain the warpage of a PCB in a specific state, but cannot obtain the evolution of its internal stress and strain. Summary of the Invention

[0007] To address the technical problems existing in the background art, the present invention provides a numerical simulation method and system for the entire life cycle of printed circuit boards. It proposes a concept and method for digital information transfer between output database files of different finite element simulations, providing a necessary technical foundation for the reliability numerical analysis of electronic components and systems such as PCBs, chips, connectors and their assemblies throughout their entire life cycle.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The first aspect of this invention provides a numerical simulation method for the entire lifecycle of a printed circuit board, comprising:

[0010] Obtain the material performance parameters of PCB and the initial and boundary conditions of the manufacturing process. Based on the finite element model of the PCB manufacturing process, obtain the numerical simulation output of the PCB manufacturing process and the model database file for storing digital information.

[0011] The digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process is used as the initial condition for the numerical simulation of the PCB service process. Adaptive adjustment of the mechanical equilibrium of the finite element model is performed at the initial moment of the numerical simulation of the PCB service process, so as to realize the inheritance of multiphysics and the continuation of numerical calculation.

[0012] After adaptive adjustment of mechanical equilibrium, numerical simulation of PCB service conditions is performed based on the finite element model of PCB service process. Finally, the entire process of PCB from manufacturing to service is numerically analyzed to predict the quality and reliability of PCB throughout its entire life cycle.

[0013] As one implementation method, the numerical simulation method for the entire lifecycle of a printed circuit board further includes:

[0014] The results of the numerical analysis of the entire PCB manufacturing process to its service life are visualized using cloud maps.

[0015] As one implementation, the model database file contains information on the stress, nodal displacements, strain, temperature, and finite element mesh of the PCB.

[0016] As one implementation, the finite element model of the PCB manufacturing process includes the geometric model of the PCB and the geometric models of the upper and lower pressure plates.

[0017] As one implementation method, the numerical simulation process of the manufacturing process based on the PCB manufacturing process finite element model includes the identification of the metal wires and insulating resins of each PCB circuit layer in the plane and the assignment of these identifications to the PCB manufacturing process finite element model.

[0018] As one implementation method, the PCB service process finite element model is established based on the service conditions studied, and includes at least a PCB geometric model and initial boundary conditions that are the same as or equivalent to those in the service process; at the initial moment of the numerical simulation of the service process, the PCB geometric model is the same as the PCB geometric model at the end moment of the numerical simulation of the manufacturing process.

[0019] A second aspect of the present invention provides a numerical simulation system for the entire lifecycle of a printed circuit board, comprising:

[0020] The PCB manufacturing process numerical simulation module is used to obtain the material performance parameters of PCB and the initial and boundary conditions of the manufacturing process. Based on the finite element model of the PCB manufacturing process, it obtains the numerical simulation output of the PCB manufacturing process and the model database file that stores digital information.

[0021] The digital information transmission module is used to use the digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process as the initial conditions for the numerical simulation of the PCB service process, and to adaptively adjust the mechanical equilibrium of the finite element model at the initial moment of the numerical simulation of the PCB service process, thereby realizing the inheritance of multiphysics and the continuation of numerical calculation.

[0022] The PCB service life numerical simulation module is used to perform numerical simulation of PCB service conditions based on the finite element model of the PCB service life after adaptive adjustment of mechanical equilibrium. Ultimately, it realizes full-process numerical analysis of PCB from manufacturing to service life, so as to predict the quality and reliability of PCB throughout its entire life cycle.

[0023] As one implementation method, the printed circuit board full lifecycle numerical simulation system further includes:

[0024] The visualization cloud map display module is used to visualize the results of the numerical analysis of the entire process of PCB manufacturing to service life.

[0025] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the numerical simulation method for the entire life cycle of a printed circuit board as described above.

[0026] A fourth aspect of the present invention provides a computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the numerical simulation method for the entire life cycle of a printed circuit board as described above.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] (1) This invention can conveniently conduct numerical simulation research on the entire life cycle of PCB, specifically including inheriting the stress and strain history and model parameters of the manufacturing process to realize full-process numerical analysis from the manufacturing process to the service process, and can predict the quality reliability represented by PCB warping deformation problem during the entire life cycle of PCB.

[0029] (2) This invention uses the digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process as the initial condition for the numerical simulation of the PCB service process. It proposes the idea and method of digital information transfer between the output database files of different finite element simulations, and provides the necessary technical basis for the reliability numerical analysis of electronic components and systems of PCB, chip, connector and their combination throughout the entire life cycle.

[0030] (3) The present invention can use the approach of finite element simulation and a small number of experimental verifications to ensure the rationality, practicality and simplicity of the proposed numerical analysis of the entire life cycle of electronic components and systems.

[0031] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0032] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0033] Figure 1 This is a flowchart of the numerical simulation method for the entire life cycle of a printed circuit board according to an embodiment of the present invention;

[0034] Figure 2 This is the temperature-time relationship curve of the fluid medium on the upper and lower surfaces of the PCB in Embodiment 1 of the present invention;

[0035] Figure 3 This is the finite element mesh model for PCB thermal cycle simulation in Embodiment 1 of the present invention;

[0036] Figure 4 This is a curve showing the relationship between the PCB warpage and the number of cycles at the highest and lowest temperatures in Embodiment 1 of the present invention. Detailed Implementation

[0037] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0038] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0039] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0040] Example 1

[0041] This embodiment provides a numerical simulation method for the entire lifecycle of a printed circuit board (PCB). Specifically, it involves inheriting the digital information stored in the output database file obtained from the PCB manufacturing process simulation into the service process simulation, thereby achieving simulation of the entire PCB lifecycle from manufacturing to service. This method establishes a service process simulation model of the PCB based on the output database file of the PCB manufacturing process simulation, realizing the full-process connection and inheritance of digital information including stress, strain, temperature, and nodal displacement.

[0042] Reference Figure 1 The numerical simulation method for the entire lifecycle of printed circuit boards in this embodiment specifically includes the following steps:

[0043] Step 1: Obtain the material performance parameters of the PCB and the initial and boundary conditions of the manufacturing process. Based on the finite element model of the PCB manufacturing process, obtain the numerical simulation output of the PCB manufacturing process and the model database file for storing digital information.

[0044] Among them, PCB material performance parameters refer to parameters that reflect the thermal, mechanical, and chemical properties of PCBs, obtained through one or more methods such as experimental testing, micromechanical equivalent models, and analytical equations.

[0045] In some embodiments, thermal, mechanical, and chemical performance parameters include one or more of the following: thermal conductivity, specific heat capacity, density, elastic modulus, shear modulus, Poisson's ratio, coefficient of thermal expansion, and coefficient of chemical contraction.

[0046] In practice, the thermal conductivity of the PCB is calculated based on the mixing ratio of copper and resin or obtained directly through experimental testing.

[0047] In step 1, the finite element model of the PCB manufacturing process is constructed by using 3D modeling software to build the geometric model of the PCB and the upper and lower pressure plates, and then importing them into the finite element software, or directly constructing the geometric model of the PCB and the upper and lower pressure plates in the finite element software; specifying material properties according to the actual material layout, and specifying initial conditions and boundary conditions according to the actual process; then specifying the PCB as a deformable solid and the upper and lower pressure plates as non-deformable rigid bodies, dividing the corresponding finite elements for both, and creating a model database file that can be used for numerical calculation.

[0048] The numerical simulation of the PCB manufacturing process includes at least the simulation of the following processes: hot pressing, cold pressing, mold opening, drilling, hole metallization, surface etching, surface electroplating, and reflow soldering.

[0049] Numerical simulation of the PCB manufacturing process includes the identification of metal conductors and insulating resins as each layer of PCB circuitry in the plane and incorporating them into the finite element model.

[0050] For example, the recognition of PCB wiring patterns is automatically implemented using a programming language script. First, the image file representing the wiring pattern is binarized, with the black pixels representing metal conductors and the rest representing resin. Then, geometric partitions are created within the image file, and the percentage of black pixels within each partition is identified. Finally, a database of the percentage of black pixels in each partition of each wiring pattern is output.

[0051] The model database file contains information on the stress, nodal displacements, strain, temperature, and finite element mesh of the PCB.

[0052] Specifically, the content of the PCB model output database file can be customized. For example, in the finite element software, the structure, material properties, and custom variables of the local or overall area of ​​the PCB model that needs to be focused on can be packaged and the physical field output variables of that area can be set.

[0053] It should be noted that the prediction results of relevant physical quantities obtained by numerical simulation technology of PCB manufacturing process should be verified by experimental results of the same process. Unless otherwise stated, the numerical simulation of PCB manufacturing process in this embodiment has been experimentally verified.

[0054] Step 2: Use the digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process as the initial conditions for the numerical simulation of the PCB service process, and perform adaptive adjustment of the mechanical equilibrium of the finite element model at the initial moment of the numerical simulation of the PCB service process, so as to realize the inheritance of multiphysics and the continuation of numerical calculation.

[0055] The PCB service process includes, but is not limited to, actual working conditions such as thermal cycling, power cycling, vibration and shock, fatigue failure, and hygrothermal-oxygen synergistic aging. Corresponding models are established based on actual problems.

[0056] Mechanical equilibrium state refers to the force state of a finite element model when it satisfies the mechanical equilibrium equation, the moment equilibrium equation, or the allowable error range.

[0057] Step 3: After adaptive adjustment of mechanical equilibrium, numerical simulation of PCB service conditions is performed based on the finite element model of PCB service process. Finally, the entire process of PCB from manufacturing to service is numerically analyzed to predict the quality and reliability of PCB throughout its entire life cycle.

[0058] The PCB service process finite element model is established based on the service conditions studied. It includes at least the PCB geometric model and the same or equivalent initial boundary conditions as the service process. At the initial moment of the service process numerical simulation, the PCB geometric model is the same as the PCB geometric model at the end of the manufacturing process numerical simulation.

[0059] The database file output from the numerical simulation of PCB service conditions based on the finite element model of the PCB service process is a file obtained from the numerical simulation process of PCB manufacturing and finite element software. It stores the spatial vector fields of PCB stress and strain and nodal displacement, the spatial scalar field of PCB temperature, and the PCB structural features and mesh graphics. The file can be opened and visualized in the finite element software.

[0060] The spatial scalar field is defined as having a definite quantity for any point M within a spatial region G. Then, a scalar field (e.g., temperature field, density field) is said to be determined within this spatial region G. A scalar field can be determined by a scalar function f(M), which is a function of spatial coordinates x, y, z and time t.

[0061] The spatial vector field is defined as having a definite vector for any point N within a spatial region Q. A vector field (e.g., force field, displacement field) is said to be determined within this spatial region Q. A vector field can be determined by a vector function f(N), which is a function of spatial coordinates x, y, z and time t.

[0062] The initial conditions of the finite element model for PCB service life refer to the use of the file import function of the finite element software to import the file storing the PCB stress-strain and nodal displacement space vector field, the PCB temperature space scalar field, and the PCB structural features and finite element mesh graphics. This allows the physical fields, PCB structural features, and mesh graphics stored in the file to be inherited at the initial moment of the finite element analysis during the PCB service life.

[0063] In some embodiments, the numerical simulation method for the entire lifecycle of a printed circuit board further includes:

[0064] This involves visualizing the results of numerical analysis of the entire PCB manufacturing and service life process using cloud maps. For example, displaying a local or overall area of ​​a model of interest with or without a mesh on a graphical interface is a process that can be achieved by professionals using existing software functions and general knowledge.

[0065] The following example illustrates the synergistic effect of PCB manufacturing process and service thermal cycling conditions on PCB warpage:

[0066] Select a commercial ten-layer PCB and obtain its material performance parameters, including density, thermal conductivity, specific heat capacity, elastic modulus, shear modulus, Poisson's ratio, and coefficient of thermal expansion, through experimental testing or micromechanical equivalent methods.

[0067] In 3D modeling software, a geometric assembly containing the PCB geometric model and the upper and lower pressure plate geometric models is created. The assembly is then imported into finite element software. The same heat transfer boundary conditions and load and displacement boundary conditions as the actual process are defined. The PCB is given the material properties from step one. A finite element model that can be used for numerical calculation is created. The output of stress, strain, nodal displacement, and temperature physical fields is defined to obtain the finite element model output database file at the end of PCB manufacturing.

[0068] In 3D modeling software, create a PCB geometric model and an assembly with the same dimensions and node information as the PCB manufacturing process simulation at its end. The assembly without the upper pressure plate is then removed. No components are mounted on the PCB surface. These models are then imported into finite element software. Using the file import function, the digital information stored in the database file output from the finite element model at the end of the PCB manufacturing process is used as the initial conditions for the current finite element model. According to the JESD22-A104E standard, condition C is selected, and the temperature-time relationship curves of the fluid medium on the upper and lower surfaces of the PCB are defined, as follows: Figure 2 As shown, thermal convection boundary conditions are set on the upper and lower surfaces of the PCB to create a thermal cycle finite element model of the PCB service process that fully inherits the physical fields of PCB stress, strain, nodal displacement, and temperature.

[0069] An external force loading-unloading method is used to create a finite element model to solve for the force equilibrium state at the initial moment of the service process. Specifically, a uniformly distributed load is applied to the upper surface of the PCB at the initial moment of the thermal cycle simulation during service, and then the load is completely released within 1 second. This yields a PCB mesh model with no stress on the upper surface and the same shape as the PCB at the end of manufacturing. This mesh model serves as the model for the thermal cycle simulation of the PCB service process. Figure 3 As shown;

[0070] Based on the obtained finite element model satisfying the mechanical equilibrium state, the relationship curves between the PCB warpage deformation and the number of cycles at the highest and lowest temperatures during the thermal cycle of the service process are obtained, as follows: Figure 4 As shown, although the warpage in the PCB thickness direction is slightly higher than the initial value at the highest and lowest temperatures during the first thermal cycle, the warpage in the PCB thickness direction gradually decreases at the highest and lowest temperatures as the number of thermal cycles increases. This is because the first thermal cycle releases a small portion of the internal stress from the PCB manufacturing process, and subsequently, due to stress relaxation, the out-of-plane warpage of the PCB gradually decreases.

[0071] Example 2

[0072] This embodiment provides a numerical simulation system for the entire lifecycle of a printed circuit board, which includes:

[0073] The PCB manufacturing process numerical simulation module is used to obtain the material performance parameters of PCB and the initial and boundary conditions of the manufacturing process. Based on the finite element model of the PCB manufacturing process, it obtains the numerical simulation output of the PCB manufacturing process and the model database file that stores digital information.

[0074] The digital information transmission module is used to use the digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process as the initial conditions for the numerical simulation of the PCB service process, and to adaptively adjust the mechanical equilibrium of the finite element model at the initial moment of the numerical simulation of the PCB service process, thereby realizing the inheritance of multiphysics and the continuation of numerical calculation.

[0075] The PCB service life numerical simulation module is used to perform numerical simulation of PCB service conditions based on the finite element model of the PCB service life after adaptive adjustment of mechanical equilibrium. Ultimately, it realizes full-process numerical analysis of PCB from manufacturing to service life, so as to predict the quality and reliability of PCB throughout its entire life cycle.

[0076] In one or more embodiments, the printed circuit board full lifecycle numerical simulation system further includes:

[0077] The visualization cloud map display module is used to visualize the results of the numerical analysis of the entire process of PCB manufacturing to service life.

[0078] It should be noted that each module in this embodiment corresponds one-to-one with each step in Embodiment 1, and their specific implementation processes are the same, so they will not be repeated here.

[0079] Example 3

[0080] This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps in the numerical simulation method for the entire lifecycle of a printed circuit board as described above.

[0081] Example 4

[0082] This embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the numerical simulation method for the entire life cycle of a printed circuit board as described above.

[0083] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0084] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A numerical simulation method for the entire lifecycle of a printed circuit board, characterized in that, include: Obtain the material performance parameters of PCB and the initial and boundary conditions of the manufacturing process. Based on the finite element model of the PCB manufacturing process, obtain the numerical simulation output of the PCB manufacturing process and the model database file for storing digital information. The model database file contains information on the stress, nodal displacements, strain, temperature, and finite element mesh of the PCB. The digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process is used as the initial condition for the numerical simulation of the PCB service process. Adaptive adjustment of the mechanical equilibrium of the finite element model is performed at the initial moment of the numerical simulation of the PCB service process, so as to realize the inheritance of multiphysics and the continuation of numerical calculation. The finite element model of the PCB manufacturing process includes the geometric model of the PCB and the geometric model of the upper and lower pressure plates; it defines the same heat transfer boundary conditions and load and displacement boundary conditions as the actual process, and defines the output of stress, strain, nodal displacement and temperature physical fields to obtain the finite element model output database file at the end of PCB manufacturing. The PCB service process includes actual working conditions such as thermal cycling, power cycling, vibration and shock, fatigue failure, and hygrothermal-oxygen synergistic aging. Corresponding models are established based on actual problems. At the initial moment of the thermal cycling simulation during the service process, a uniformly distributed load is applied to the upper surface of the PCB, and then the load is completely released to obtain a PCB mesh model with no stress on the upper surface of the PCB and the same shape as the PCB at the end of manufacturing. After adaptive adjustment of mechanical equilibrium, numerical simulation of PCB service conditions is carried out based on the finite element model of PCB service process. Finally, the full-process numerical analysis of PCB from manufacturing process to service process is realized to predict the quality reliability of PCB throughout its entire life cycle. Create a PCB geometric model with the same dimensions and node information as the PCB manufacturing process simulation at the end time, and an assembly with the upper pressure plate removed. Define the temperature-time relationship curves of the fluid medium on the upper and lower surfaces of the PCB, set the thermal convection boundary conditions on the upper and lower surfaces of the PCB, and create a thermal cycling finite element model of the PCB service process that fully inherits the PCB stress, strain, node displacement, and temperature physical fields. The PCB service process finite element model is a finite element model based on the studied service conditions, which includes at least the PCB geometric model and the same or equivalent initial boundary conditions as the service process. At the initial time of the service process numerical simulation, this PCB geometric model is the same as the PCB geometric model at the end time of the manufacturing process numerical simulation.

2. The numerical simulation method for the entire lifecycle of a printed circuit board as described in claim 1, characterized in that, The numerical simulation method for the entire lifecycle of printed circuit boards also includes: The results of the numerical analysis of the entire PCB manufacturing process to its service life are visualized using cloud maps.

3. The numerical simulation method for the entire lifecycle of a printed circuit board as described in claim 1, characterized in that, The numerical simulation process of the manufacturing process based on the finite element model of PCB manufacturing process includes the identification of metal wires and insulating resins as each layer of PCB circuit in the plane and the assignment of these identifications to the finite element model of PCB manufacturing process.

4. A numerical simulation system for the entire lifecycle of a printed circuit board, characterized in that, include: The PCB manufacturing process numerical simulation module is used to obtain the material performance parameters of PCB and the initial and boundary conditions of the manufacturing process. Based on the finite element model of the PCB manufacturing process, it obtains the numerical simulation output of the PCB manufacturing process and the model database file that stores digital information. The model database file contains information on the stress, nodal displacements, strain, temperature, and finite element mesh of the PCB. The digital information transmission module is used to use the digital information stored in the model database file output by the numerical simulation of the PCB manufacturing process as the initial conditions for the numerical simulation of the PCB service process, and to adaptively adjust the mechanical equilibrium of the finite element model at the initial moment of the numerical simulation of the PCB service process, thereby realizing the inheritance of multiphysics and the continuation of numerical calculation. The finite element model of the PCB manufacturing process includes the geometric model of the PCB and the geometric model of the upper and lower pressure plates; it defines the same heat transfer boundary conditions and load and displacement boundary conditions as the actual process, and defines the output of stress, strain, nodal displacement and temperature physical fields to obtain the finite element model output database file at the end of PCB manufacturing. The PCB service process includes actual working conditions such as thermal cycling, power cycling, vibration and shock, fatigue failure, and hygrothermal-oxygen synergistic aging. Corresponding models are established based on actual problems. At the initial moment of the thermal cycling simulation during the service process, a uniformly distributed load is applied to the upper surface of the PCB, and then the load is completely released to obtain a PCB mesh model with no stress on the upper surface of the PCB and the same shape as the PCB at the end of manufacturing. The PCB service life numerical simulation module is used to perform numerical simulation of PCB service conditions based on the PCB service life finite element model after adaptive adjustment of mechanical balance. Ultimately, it realizes full-process numerical analysis of PCB from manufacturing to service life, so as to predict the quality reliability of PCB throughout its entire life cycle. Create a PCB geometric model with the same dimensions and node information as the PCB manufacturing process simulation at the end time, and an assembly with the upper pressure plate removed. Define the temperature-time relationship curves of the fluid medium on the upper and lower surfaces of the PCB, set the thermal convection boundary conditions on the upper and lower surfaces of the PCB, and create a thermal cycling finite element model of the PCB service process that fully inherits the PCB stress, strain, node displacement, and temperature physical fields. The PCB service process finite element model is a finite element model based on the studied service conditions, which includes at least the PCB geometric model and the same or equivalent initial boundary conditions as the service process. At the initial time of the service process numerical simulation, this PCB geometric model is the same as the PCB geometric model at the end time of the manufacturing process numerical simulation.

5. The numerical simulation system for the entire lifecycle of a printed circuit board as described in claim 4, characterized in that, The printed circuit board full lifecycle numerical simulation system also includes: The visualization cloud map display module is used to visualize the results of the numerical analysis of the entire process of PCB manufacturing to service life.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the numerical simulation method for the entire life cycle of a printed circuit board as described in any one of claims 1-3.

7. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the numerical simulation method for the entire life cycle of a printed circuit board as described in any one of claims 1-3.

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