Method and apparatus for analysing residual stresses after assembly, storage medium and electronic device

Abstract

Provided in the present invention are a method and apparatus for analysing residual stresses after assembly, a storage medium and an electronic device, relating to the technical field of stress analysis. For assembly technology that generates large residual stresses during assembly processes and requires overall thermal treatment, the technical solution of the present invention comprises performing finite element modeling on a heat transfer process of the technology, further performing testing and calibration on key thermal parameters to obtain a temperature distribution of a microwave component after each assembly process step, so as to obtain a residual stress distribution of the microwave component after each assembly process step, and finally obtaining a residual stress distribution of the microwave component after assembly. Therefore, the present invention solves the technical issue of analyzing residual stresses after assembly.

Description

Post-assembly residual stress analysis method, device, storage medium and electronic device Technical Field

[0001] The present invention relates to the technical field of stress analysis, and in particular to a post-assembly residual stress analysis method, device, storage medium and electronic equipment. Background Art

[0002] Microwave components serve as the receiving and transmitting channels for microwave signals and are one of the most critical modules in radar. Their performance directly determines the technical specifications of the entire radar. Residual stress generated during the assembly process is a significant factor affecting the overall performance of microwave components.

[0003] Currently, there is a lack of systematic analysis methods for residual stress generated after assembly. With the miniaturization, array formation, and integrated development of radar systems, microwave components are developing towards high density, three-dimensionality, and integration. The superposition of process residual stress and operating stress will further deteriorate the working state of microwave components, and the impact of residual stress on the life and performance of microwave components will become more significant.

[0004] Therefore, a method that can systematically analyze residual stress after assembly is urgently needed.

[0005] Summary of the Invention

[0006] (1) Technical problems solved

[0007] In view of the deficiencies in the prior art, the present invention provides a method, device, storage medium and electronic device for analyzing residual stress after assembly, which solve the problem of how to analyze residual stress after assembly.

[0008] (2) Technical solution

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0010] In a first aspect, a post-assembly residual stress analysis method is provided, the method comprising:

[0011] Obtain a finite element mesh model of the entire assembly and a finite element mesh model of the tooling required for the high-temperature treatment process during assembly;

[0012] Based on the finite element mesh model, simulate and analyze each high-temperature treatment process to obtain the residual stress distribution of each high-temperature treatment process;

[0013] The residual stress distributions obtained from each high-temperature treatment process are superimposed to obtain the residual stress distribution after assembly.

[0014] Furthermore, the simulation analysis of each high temperature treatment process based on the finite element mesh model to obtain the residual stress distribution of each high temperature treatment process includes:

[0015] Thermal simulation is performed based on the thermal analysis model of the high-temperature treatment process to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder;

[0016] Mechanical simulation is performed based on the mechanical analysis model of the high-temperature treatment process and the corresponding temperature distribution to obtain the residual stress distribution when cooling to room temperature.

[0017] Furthermore, the thermal analysis model based on the high temperature treatment process is used to perform thermal simulation to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder, including:

[0018] Based on the finite element mesh model corresponding to the high-temperature treatment process, transient thermal analysis was performed using finite element analysis software to obtain the temperature distribution when the temperature control curve before calibration dropped to the solder melting point;

[0019] Based on the temperature distribution when the temperature control curve before calibration drops to the melting point of the solder, the calibration results of key thermal parameters corresponding to the high temperature treatment process are obtained;

[0020] Based on the calibration results of key thermal parameters, transient thermal analysis was performed again using finite element analysis software to obtain the temperature distribution when the calibrated temperature control curve dropped to the melting point of the solder.

[0021] Furthermore, when the high temperature treatment process is hot plate welding, the key thermal parameter is the interface thermal resistance between the hot plate and the assembly;

[0022] When the high temperature treatment process is reflow soldering, vacuum reflow soldering or vacuum vapor phase soldering, the key thermal parameter is the convection heat transfer coefficient;

[0023] When the high-temperature treatment process is low-temperature vacuum brazing, the key thermal parameter is surface emissivity.

[0024] In a second aspect, a post-assembly residual stress analysis device is provided, the device comprising:

[0025] Finite element mesh model acquisition module, used to obtain the finite element mesh model of the entire assembly and the finite element mesh model of the tooling required for the high-temperature treatment process during the assembly process;

[0026] The residual stress distribution analysis module of the high-temperature treatment process is used to simulate and analyze each high-temperature treatment process and obtain the residual stress distribution of each high-temperature treatment process;

[0027] The post-assembly residual stress distribution acquisition module is used to superimpose the residual stress distributions obtained from various high-temperature treatment processes to obtain the post-assembly residual stress distribution.

[0028] Furthermore, the residual stress distribution analysis module of the high temperature treatment process includes:

[0029] A temperature distribution acquisition unit for a high-temperature treatment process is used to perform thermal simulation based on a thermal analysis model of the high-temperature treatment process to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder;

[0030] The residual stress distribution acquisition unit of the high temperature treatment process is used to perform mechanical simulation based on the mechanical analysis model of the high temperature treatment process and the corresponding temperature distribution to obtain the residual stress distribution when cooling to room temperature.

[0031] Furthermore, the thermal analysis model based on the high temperature treatment process is used to perform thermal simulation to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder, including:

[0032] Based on the finite element mesh model corresponding to the high-temperature treatment process, transient thermal analysis was performed using finite element analysis software to obtain the temperature distribution when the temperature control curve before calibration dropped to the solder melting point;

[0033] Based on the temperature distribution when the temperature control curve before calibration drops to the melting point of the solder, the calibration results of key thermal parameters corresponding to the high temperature treatment process are obtained;

[0034] Based on the calibration results of key thermal parameters, transient thermal analysis was performed again using finite element analysis software to obtain the temperature distribution when the calibrated temperature control curve dropped to the melting point of the solder.

[0035] Furthermore, when the high temperature treatment process is hot plate welding, the key thermal parameter is the interface thermal resistance between the hot plate and the assembly;

[0036] When the high temperature treatment process is reflow soldering, vacuum reflow soldering or vacuum vapor phase soldering, the key thermal parameter is the convection heat transfer coefficient;

[0037] When the high-temperature treatment process is low-temperature vacuum brazing, the key thermal parameter is surface emissivity.

[0038] In a third aspect, a computer-readable storage medium is provided, which stores a computer program for post-assembly residual stress analysis, wherein the computer program enables a computer to execute the above-mentioned post-assembly residual stress analysis method.

[0039] In a fourth aspect, an electronic device is provided, including:

[0040] one or more processors;

[0041] Memory; and

[0042] One or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for executing the above-mentioned post-assembly residual stress analysis method. (3) Beneficial effects

[0043] The present invention provides a post-assembly residual stress analysis method, device, storage medium, and electronic device. Compared with the prior art, the present invention has the following advantages:

[0044] The technical solution of the present invention is aimed at an assembly process that generates large residual stress and requires overall heat treatment. Finite element modeling is performed on the heat exchange process of the process, and key thermal parameters are tested and calibrated. The temperature distribution of the microwave component after each assembly process step is obtained, thereby obtaining the residual stress distribution of the microwave component after each assembly process step, and finally obtaining the residual stress distribution of the microwave component after assembly, thereby solving the technical problem of how to analyze the residual stress after assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0046] FIG1 is a flow chart of an embodiment of the present invention;

[0047] FIG2 is a schematic structural diagram of a microwave assembly according to an embodiment of the present invention;

[0048] FIG3 is a schematic diagram of tooling required for a high-temperature treatment process according to an embodiment of the present invention;

[0049] FIG4 is a flow chart of obtaining residual stress distributions of various high temperature treatment processes according to an embodiment of the present invention;

[0050] FIG5 is a flow chart of thermal simulation based on a thermal analysis model of a high temperature treatment process according to an embodiment of the present invention. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0052] The embodiments of the present application solve the problem of how to analyze residual stress after assembly by providing a method, device, storage medium and electronic device for analyzing residual stress after assembly.

[0053] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0054] Example 1:

[0055] As shown in FIG1 , the present invention provides a method for analyzing residual stress after assembly, which is executed by a computer and includes:

[0056] Obtain a finite element mesh model of the entire assembly and a finite element mesh model of the tooling required for the high-temperature treatment process during assembly;

[0057] Based on the finite element mesh model, simulate and analyze each high-temperature treatment process to obtain the residual stress distribution of each high-temperature treatment process;

[0058] The residual stress distributions obtained from each high-temperature treatment process are superimposed to obtain the residual stress distribution after assembly.

[0059] The beneficial effects of this embodiment are:

[0060] The technical solution of this embodiment is aimed at assembly processes that require overall heat treatment and generate large residual stresses during the assembly process. Finite element modeling is performed on the heat exchange process of the process, and key thermal parameters are tested and calibrated. The temperature distribution of the microwave component after each assembly process step is obtained, and the residual stress distribution of the microwave component after each assembly process step is obtained. Finally, the residual stress distribution of the microwave component after assembly is obtained, solving the technical problem of how to analyze the residual stress after assembly.

[0061] The following describes the implementation process of the embodiment of the present invention in detail using the assembly of a microwave component as an example:

[0062] As shown in Figure 2, the microwave assembly includes: a box body, an LTCC substrate, a connector, spacers, a carrier module, components, a carrier, a power chip, and a cover.

[0063] Among them, the LTCC substrate is assembled in the box body, and the connector is assembled on the box body; the partition ribs are assembled on the LTCC substrate to form mutually isolated microwave channels; the carrier module and components are assembled on the LTCC substrate, and the carrier module is further composed of a carrier and a power chip assembled on the carrier; the cover plate is sealed on the box body.

[0064] The assembly process of microwave components is:

[0065] 1) Solder the power chip to the carrier by hot plate soldering (solder: gold tin) to obtain a carrier module;

[0066] 2) Bonding some components to the LTCC substrate by gluing;

[0067] 3) Solder the chip carrier module, other components and ribs to the LTCC substrate through reflow soldering (solder: SAC305);

[0068] 4) Solder the LTCC substrate, connector, and box body using low-temperature vacuum brazing (solder: tin-lead);

[0069] 5) Weld the box body and the cover plate by laser welding.

[0070] Therefore, the high-temperature processing processes involved in the assembly process of microwave components include: hot plate welding, reflow soldering, vacuum reflow soldering, vacuum vapor phase soldering and low-temperature vacuum brazing, etc. The process usually requires tooling assistance. Taking reflow soldering as an example, it can be a block tool as shown in Figure 3, which applies pressure to the welding surface or optimizes the heat transfer of the structure. After long-term research and practice, the inventors found that when the welding surface reaches the temperature window, the heat transfer process of the microwave component and the corresponding tooling is different under different process conditions, the temperature response of different areas of the structure is different, and the temperature distribution is uneven. In addition to the different thermal expansion coefficients of the constituent materials of the microwave component, the difference in the temperature distribution of the structure will also directly lead to large residual stress after assembly. Therefore, it is necessary to analyze the residual stress of the microwave component after the multi-step assembly process while taking into account the uneven temperature distribution of the microwave component.

[0071] The inventors targeted an assembly process that would generate large residual stresses and require overall heat treatment. They performed finite element modeling on the heat exchange process of the process and tested and calibrated key thermal parameters to obtain the temperature distribution of the microwave component after each assembly process step, thereby obtaining the residual stress distribution of the microwave component after each assembly process step, and finally obtaining the residual stress distribution of the microwave component after assembly, thus solving the technical difficulties existing in the background technology.

[0072] The specific steps include:

[0073] S1. Based on the high-temperature processing involved in the assembly process of the microwave component, obtain the overall three-dimensional model of the microwave component and the three-dimensional model of the tooling required for each high-temperature processing process.

[0074] In a specific implementation, as shown in Figure 2, the overall 3D model of the microwave assembly includes the individual components that make up the microwave assembly. The 3D models of the tooling required for each high-temperature processing process (hot plate soldering, reflow soldering, low-temperature vacuum brazing, etc.) include the tooling components used in each process. The 3D model can be in STP format.

[0075] S2. Obtain a finite element mesh model of the entire microwave assembly based on the three-dimensional model of the entire microwave assembly, and obtain a finite element mesh model of the tooling required for each high-temperature treatment process based on the three-dimensional model of the tooling required for each high-temperature treatment process.

[0076] In specific implementations, this further includes obtaining the material properties and assigned meshes corresponding to each finite element mesh model; and extracting the finite element mesh model required for each process from the finite element mesh model for subsequent analysis steps. The finite element mesh model can be in the inp format.

[0077] S3. Based on the finite element mesh model, simulate and analyze each high-temperature treatment process to obtain the residual stress distribution of each high-temperature treatment process, as shown in Figure 4. Specifically, it includes S3.1 to S3.2:

[0078] S3.1. Perform thermal simulation based on the thermal analysis model of the high-temperature treatment process to obtain the temperature distribution when the temperature control curve drops to the solder melting point, as shown in Figure 5. This specifically includes S3.1.1 to S3.1.3:

[0079] S3.1.1. Based on the finite element mesh model corresponding to the high-temperature treatment process, use finite element analysis software to perform transient thermal analysis to obtain the temperature distribution (simulated value) when the pre-calibration temperature control curve drops to the solder melting point;

[0080] S3.1.2. Based on the temperature distribution when the temperature control curve before calibration is lowered to the melting point of the solder, obtain the calibration results of the key thermal parameters corresponding to the high temperature treatment process;

[0081] S3.1.3. Based on the calibration results of key thermal parameters, the transient thermal analysis is performed again using the finite element analysis software to obtain the temperature distribution (simulated value) when the calibrated temperature control curve drops to the solder melting point.

[0082] In specific implementation, the thermal simulation steps of different high-temperature treatment processes are different. The following takes hot plate soldering, reflow soldering, and low-temperature vacuum brazing involved in the assembly of microwave components as an example for specific explanation.

[0083] 1 The first high temperature treatment process is to assemble the power chip and the carrier by hot plate welding. The key thermal parameter is the interface thermal resistance R between the hot plate and the assembly. imp, the specific steps include:

[0084] The finite element mesh model of the hot plate welding assembly power chip and carrier and the corresponding tooling was imported into the finite element analysis software Abaqus. When setting up the software, the hot plate was used as the heat source, the temperature was set to the temperature control curve set by the hot plate, and the empirical value of the interface thermal resistance between the hot plate and the assembly was 0.5E-4 to 5E-4 K·m 2 / W, take 2E-4K·m 2 / W; transient thermal analysis was performed using finite element analysis software to obtain the temperature distribution of the microwave component when the hot stage temperature control curve dropped to 280°C, the melting point of gold-tin solder;

[0085] The calibration method of the interface thermal resistance between the hot plate and the assembly is: Min f(α)=∑(αT K -t K ) 2 R′ imp =α*R imp

[0086] Among them, α represents the correction coefficient when f(α) is the smallest, which is obtained after calculation;

[0087] T K represents the temperature simulation value of the Kth detection point, obtained by the simulation software;

[0088] t K The temperature detection value at the Kth detection point is obtained by a temperature sensor placed on the surface of the test piece or at the internal test hole;

[0089] R imp It represents the empirical value of the interface thermal resistance between the hot plate and the assembly;

[0090] R′ imp represents the corrected empirical value of the interface thermal resistance between the hot plate and the assembly;

[0091] Based on the corrected empirical value of the interface thermal resistance R′ between the hot plate and the assembly imp , and then perform transient thermal analysis again to obtain the temperature distribution of the microwave component when the corrected hot stage temperature control curve drops to the solder melting point.

[0092] 2 The second high temperature treatment process is to reflow the module, other components, ribs and substrate. The key thermal parameter is the convection heat transfer coefficient h. The specific steps include:

[0093] The finite element mesh model of the carrier module, other components, ribs, LTCC substrate and corresponding tooling was imported into the finite element analysis software Abaqus. Among them, the surface of the assembly and tooling in contact with the hot air is the convection heat transfer surface, and the empirical value of the convection heat transfer coefficient h is 20~300W / (m 2 ·K), take 100W / (m 2 K), the hot air temperature is set to the temperature control curve set by the furnace body; transient thermal analysis is performed using finite element analysis software to obtain the temperature distribution of the microwave component when the furnace body temperature control curve is reduced to 218°C, the melting point of SAC305 solder;

[0094] The method for calibrating the convective heat transfer coefficient is:

[0095] Place 5 temperature sensors on the assembly or tooling surface.

[0096] Among them, α represents the correction coefficient when f(α) is the smallest, which is obtained after calculation;

[0097] T K represents the temperature simulation value of the Kth detection point, obtained by the simulation software;

[0098] t K represents the temperature detection value of the Kth detection point, obtained by the temperature sensor;

[0099] h represents the empirical value of the convective heat transfer coefficient;

[0100] h' represents the corrected convective heat transfer coefficient;

[0101] Based on the revised convection heat transfer coefficient h', transient thermal analysis was performed again to obtain the temperature distribution of the microwave component when the revised furnace temperature control curve dropped to the solder melting point.

[0102] And the steps of vacuum reflow soldering or vacuum vapor soldering are similar to those of reflow soldering.

[0103] The third high-temperature treatment process is to assemble the LTCC substrate, connector, and box body by low-temperature vacuum brazing. The key thermal parameter is the emissivity ε of the assembly and tooling surface. The specific steps include:

[0104] Import the corresponding finite element mesh model's inp file into Abaqus. Set the heating wire inside the furnace as a radiation heat source, take the emissivity ε of the assembly and tooling surfaces as an empirical value of 0.5 W / (m·K), and set the radiation source temperature to the furnace temperature control curve. Use finite element analysis software to perform transient thermal analysis and obtain the temperature distribution of the microwave assembly when the furnace temperature control curve drops to the solder melting point.

[0105] The calibration method of the emissivity ε of the assembly and tooling surface is as follows: place three temperature sensors on the surface of the assembly,

[0106] Among them, α represents the correction coefficient when f(α) is the smallest, which is obtained after calculation;

[0107] T K represents the temperature simulation value of the Kth detection point, obtained by the simulation software;

[0108] t K represents the temperature detection value of the Kth detection point, obtained by the temperature sensor;

[0109] h represents the empirical value of surface emissivity;

[0110] h' represents the corrected surface emissivity;

[0111] Based on the corrected surface emissivity ε', transient thermal analysis was performed again to obtain the temperature distribution of the microwave component when the corrected furnace temperature control curve dropped to the solder melting point.

[0112] S3.2. Perform mechanical simulation based on the mechanical analysis model of the high-temperature treatment process and the corresponding temperature distribution to obtain the residual stress distribution σ when the microwave component is cooled to room temperature.

[0113] During specific implementation, a mechanical analysis model corresponding to the high-temperature treatment process is established, and a mechanical constraint boundary is added to the finite element mesh model of the high-temperature treatment process, that is, the vertical degree of freedom of the bottom surface of the assembly is constrained. The obtained temperature distribution is added to the model, and mechanical simulation is performed to obtain the residual stress distribution σ when the microwave component is cooled to room temperature, where tensile stress is positive and compressive stress is negative.

[0114] S4. Superimpose the residual stress distribution σ obtained during the high-temperature treatment process to obtain the residual stress distribution after assembly.

[0115] Example 2:

[0116] A post-assembly residual stress analysis device, comprising:

[0117] Finite element mesh model acquisition module, used to obtain the finite element mesh model of the entire assembly and the finite element mesh model of the tooling required for the high-temperature treatment process during the assembly process;

[0118] The residual stress distribution analysis module of the high-temperature treatment process is used to simulate and analyze each high-temperature treatment process and obtain the residual stress distribution of each high-temperature treatment process;

[0119] The post-assembly residual stress distribution acquisition module is used to superimpose the residual stress distributions obtained from various high-temperature treatment processes to obtain the post-assembly residual stress distribution.

[0120] The residual stress distribution analysis module of the high temperature treatment process includes:

[0121] A temperature distribution acquisition unit for a high-temperature treatment process is used to perform thermal simulation based on a thermal analysis model of the high-temperature treatment process to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder;

[0122] The residual stress distribution acquisition unit of the high temperature treatment process is used to perform mechanical simulation based on the mechanical analysis model of the high temperature treatment process and the corresponding temperature distribution to obtain the residual stress distribution when cooling to room temperature.

[0123] Example 3:

[0124] A computer-readable storage medium stores a computer program for post-assembly residual stress analysis, wherein the computer program causes a computer to execute the following steps:

[0125] Obtain a finite element mesh model of the entire assembly and a finite element mesh model of the tooling required for the high-temperature treatment process during assembly;

[0126] Based on the finite element mesh model, simulate and analyze each high-temperature treatment process to obtain the residual stress distribution of each high-temperature treatment process;

[0127] The residual stress distributions obtained from each high-temperature treatment process are superimposed to obtain the residual stress distribution after assembly.

[0128] Example 4:

[0129] An electronic device, comprising:

[0130] one or more processors;

[0131] Memory; and

[0132] One or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs comprising steps for performing the following steps:

[0133] Obtain a finite element mesh model of the entire assembly and a finite element mesh model of the tooling required for the high-temperature treatment process during assembly;

[0134] Based on the finite element mesh model, simulate and analyze each high-temperature treatment process to obtain the residual stress distribution of each high-temperature treatment process;

[0135] The residual stress distributions obtained from each high-temperature treatment process are superimposed to obtain the residual stress distribution after assembly.

[0136] It is understandable that the post-assembly residual stress analysis device, computer-readable storage medium, and electronic device provided in the embodiments of the present invention correspond to the above-mentioned post-assembly residual stress analysis method. The explanations, examples, beneficial effects, etc. of the relevant contents can refer to the corresponding contents in the post-assembly residual stress analysis method and will not be repeated here.

[0137] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0138] 1. The present invention takes into account the differences in heat exchange mechanisms of different assembly processes and adopts different thermal models for different assembly processes, which can truly reflect the temperature distribution of microwave components during the process;

[0139] 2. The present invention adopts a method combining simulation and testing to calibrate the key parameters of the heat exchange model, thereby improving the accuracy of the calculation results;

[0140] 3. The present invention integrates the influence of tooling on the temperature distribution of microwave components to more accurately model the assembly process;

[0141] 4. The present invention realizes the correlation analysis of the residual stress of microwave components in related process steps through the method of thermomechanical coupling based on the temperature distribution law of microwave components.

[0142] It should be noted that, through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus the necessary general hardware platform. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiment. In this article, relational terms such as first and second are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. Without further constraints, an element defined by the phrase "comprises a..." does not preclude the existence of additional identical elements in the process, method, article or apparatus that includes the element.

[0143] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for analyzing residual stress after assembly, characterized in that: The method includes: Obtain the finite element mesh model of the entire assembly and the finite element mesh model of the tooling required for the high temperature treatment process during the assembly process; Based on the finite element mesh model, each high temperature treatment process is simulated and analyzed to obtain the residual stress distribution of each high temperature treatment process; The residual stress distributions obtained from each high-temperature treatment process are superimposed to obtain the residual stress distribution after assembly.

2. A post-assembly residual stress analysis method as claimed in claim 1, characterized in that: The finite element mesh model is used to simulate and analyze each high temperature treatment process to obtain the residual stress distribution of each high temperature treatment process, including: Thermal simulation is performed based on the thermal analysis model of the high temperature treatment process to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder; Mechanical simulation is performed based on the mechanical analysis model of the high temperature treatment process and the corresponding temperature distribution to obtain the residual stress distribution when cooled to room temperature.

3. A post-assembly residual stress analysis method as claimed in claim 2, characterized in that: The thermal analysis model based on the high temperature treatment process performs thermal simulation to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder, including: Based on the finite element mesh model corresponding to the high temperature treatment process, transient thermal analysis was performed using finite element analysis software to obtain the temperature distribution when the temperature control curve before calibration dropped to the melting point of the solder; Based on the temperature distribution when the temperature control curve before calibration drops to the melting point of the solder, the calibration results of key thermal parameters corresponding to the high temperature treatment process are obtained; Based on the calibration results of key thermal parameters, transient thermal analysis was performed again using finite element analysis software to obtain the temperature distribution when the calibrated temperature control curve dropped to the melting point of the solder.

4. A post-assembly residual stress analysis method as claimed in claim 3, characterized in that: When the high temperature treatment process is hot plate welding, the key thermal parameter is the interface thermal resistance between the hot plate and the assembly; When the high temperature treatment process is reflow soldering, vacuum reflow soldering or vacuum vapor soldering, the key thermal The parameter is the convective heat transfer coefficient; When the high temperature treatment process is low temperature vacuum brazing, the key thermal parameter is surface emissivity.

5. A post-assembly residual stress analysis device, characterized in that: The device includes: A finite element mesh model acquisition module is used to obtain the finite element mesh model of the entire assembly and the finite element mesh model of the tooling required for the high temperature treatment process during the assembly process; The residual stress distribution analysis module of the high temperature treatment process is used to simulate and analyze each high temperature treatment process and obtain the residual stress distribution of each high temperature treatment process; The post-assembly residual stress distribution acquisition module is used to superimpose the acquired residual stress distributions of each high-temperature treatment process to obtain the post-assembly residual stress distribution.

6. A post-assembly residual stress analysis device as claimed in claim 5, characterized in that: The residual stress distribution analysis module of the high temperature treatment process includes: A temperature distribution acquisition unit for a high temperature treatment process is used to perform thermal simulation based on a thermal analysis model of the high temperature treatment process to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder; The residual stress distribution acquisition unit of the high temperature treatment process is used to perform mechanical simulation based on the mechanical analysis model of the high temperature treatment process and the corresponding temperature distribution to obtain the residual stress distribution when cooled to room temperature.

7. A post-assembly residual stress analysis device as claimed in claim 6, characterized in that: The thermal analysis model based on the high temperature treatment process performs thermal simulation to obtain the temperature distribution when the temperature control curve drops to the melting point of the solder, including: Based on the finite element mesh model corresponding to the high temperature treatment process, transient thermal analysis was performed using finite element analysis software to obtain the temperature distribution when the temperature control curve before calibration dropped to the melting point of the solder; Based on the temperature distribution when the temperature control curve before calibration drops to the melting point of the solder, the calibration results of key thermal parameters corresponding to the high temperature treatment process are obtained; Based on the calibration results of key thermal parameters, transient thermal analysis was performed again using finite element analysis software to obtain the temperature distribution when the calibrated temperature control curve dropped to the melting point of the solder.

8. A post-assembly residual stress analysis device as claimed in claim 7, characterized in that: When the high temperature treatment process is hot plate welding, the key thermal parameter is the interface thermal resistance between the hot plate and the assembly; When the high temperature treatment process is reflow soldering, vacuum reflow soldering or vacuum vapor soldering, the key thermal The parameter is the convective heat transfer coefficient; When the high temperature treatment process is low temperature vacuum brazing, the key thermal parameter is surface emissivity.

9. A computer-readable storage medium, characterized in that: The computer program for post-assembly residual stress analysis is stored therein, wherein the computer program enables a computer to execute the post-assembly residual stress analysis method according to any one of claims 1 to 4.

10. An electronic device, characterized in that: include: one or more processors; Memory; as well as One or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for executing the post-assembly residual stress analysis method according to any one of claims 1 to 4.

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