Virtual detection and evaluation method and system for injection molding of automobile plastic parts

Abstract

The present invention is applicable to the field of injection molding, and provides a virtual detection and evaluation method and system for injection molding of automotive plastic parts. The system includes: a data acquisition and real-time monitoring module, a temperature field model construction and thermal analysis module, a performance change analysis module, and a virtual experiment and performance evaluation module. The method can systematically evaluate the performance and reliability of injection molded parts under actual use conditions through accurate thermal field simulation and stress analysis. In addition, combined with fatigue theory and oxidation reaction analysis, it provides a scientific basis for predicting the service life and performance changes of materials, making the prediction results more accurate and reliable. This can not only effectively identify potential failure modes, but also provide data support for design optimization and material selection to improve product quality and durability. At the same time, the use of virtual detection technology reduces the cost and time of actual testing, improves R&D efficiency, and promotes the process of intelligent manufacturing.

Description

Technical Field

[0001] The invention belongs to the field of injection molding, and in particular relates to a virtual detection and evaluation method and system for injection molding of automobile plastic parts. Background Art

[0002] Injection molding of automotive plastic parts is an integral part of modern automobile manufacturing, involving the processing of plastic materials into various functional and structural parts through injection molding. The main advantages of this field include lightweight, cost-effectiveness and design flexibility, which can effectively meet the multiple requirements of the automotive industry for performance, appearance and cost.

[0003] In the production process of automotive plastic injection molded parts, sensitivity to temperature can lead to a series of inspection defects. Frequent and drastic temperature fluctuations can cause changes in the physical properties of plastic materials. For example, the material may become more fragile and prone to breaking when stressed, while long-term uneven temperature gradients may lead to the formation of fatigue cracks. In high temperature environments, such as engine accessories, plastic materials are prone to oxidation and degradation, which manifests as color changes and reduced strength.

[0004] In addition, thermal deformation and stress concentration in high temperature environments can also cause permanent deformation of plastic parts, affecting their assembly and function. In terms of surface quality, temperature fluctuations may lead to uneven surface roughness and the generation of bubbles and impurities, further affecting the appearance and performance of the product. In terms of dimensional accuracy, shrinkage and warping may be caused by temperature changes, resulting in the final product's dimensions not meeting specifications, especially shape deformation caused by uneven shrinkage during cooling. Summary of the invention

[0005] The purpose of the present invention is to provide a virtual detection and evaluation method for injection molding of automobile plastic parts, aiming to solve the technical problems existing in the prior art identified in the background technology.

[0006] The present invention is implemented in this way: a virtual detection and evaluation method for injection molding of automobile plastic parts, the method comprising:

[0007] Acquire existing injection molding production data and collect the production environment data of the current injection molding site in real time;

[0008] Construct a temperature field model to simulate the temperature changes and heat conduction experienced by injection molded parts during production and use, analyze the deformation, fatigue and oxidation reactions of injection molded parts in high temperature environments, and record the simulation and analysis results;

[0009] Extract performance characteristics from the recorded results, establish a performance change model, and predict the performance changes of injection molded parts under different environmental conditions based on the extracted performance characteristics;

[0010] Build a virtual experimental environment to simulate the performance of injection molded parts under different environmental conditions, and combine the predicted results of performance changes to evaluate the durability, fatigue limit and oxidation risk of injection molded parts.

[0011] As a further solution of the present invention, the acquisition of existing injection molding production data and real-time collection of production environment data of the current injection molding site specifically includes:

[0012] Extract past injection molding production records from the production database, including the parameters of each production batch;

[0013] Collect the characteristic data of the plastic materials used and summarize the records of injection molding defects in historical data;

[0014] Monitor environmental parameters during the production process in real time, integrate the real-time collected environmental data with historical injection molding production data, and analyze the relationship between temperature fluctuations, humidity changes and production parameters.

[0015] As a further solution of the present invention, the simulation of the temperature change and heat conduction experienced by the injection molded parts during production and use, and the analysis of the deformation, fatigue and oxidation reaction of the injection molded parts in a high temperature environment, specifically include:

[0016] Create geometric models of injection molded parts and define the thermophysical properties of plastic materials;

[0017] Determine the heat exchange boundary conditions between the injection molded part and the environment, and set the initial temperature distribution of the injection molded part at the beginning of the simulation;

[0018] Based on the set conditions, the temperature field time domain simulation is performed on the created injection molded part geometric model, the temperature distribution of the injection molded part at different time points is analyzed, the temperature changes inside and on the surface of the injection molded part are calculated, and the temperature distribution results in different time periods are recorded;

[0019] Based on the temperature field results, calculate the thermal stress caused by temperature changes and analyze the stress distribution of injection molded parts in high temperature environments;

[0020] Use material fatigue theory, combined with temperature and stress data, to predict the fatigue life and fatigue limit of materials;

[0021] Considering the relationship between oxidation reaction rate, temperature and time, the oxidation process of materials at high temperature is simulated, and the changes in material properties caused by oxidation are recorded.

[0022] As a further solution of the present invention, the thermal stress generated by temperature change is calculated based on the temperature field result, specifically:

[0023] ;

[0024] Where, is the final thermal stress value, is the mechanical stress caused by external loads or constraints, is the theoretical thermal stress;

[0025] ;

[0026] in, is the elastic modulus of the material, is the current thermal expansion coefficient of the material, is the temperature change value.

[0027] As a further solution of the present invention, the predicted fatigue life of the material specifically includes:

[0028] ;

[0029] in, represents fatigue life, Display material The stress amplitude, is the material constant;

[0030] ;

[0031] in, are the maximum and minimum stresses of a material under cyclic loading.

[0032] As a further solution of the present invention, the fatigue limit prediction includes:

[0033] ;

[0034] in, represents the fatigue limit, represents the mean stress, Represents tensile strength, Represents the stress amplitude.

[0035] As a further solution of the present invention, the establishment of a performance change model predicts the performance change of the injection molded part under different environmental conditions based on the extracted performance characteristics, specifically including:

[0036] Define the performance indicators that affect injection molded parts, including temperature cycle number, fatigue limit, fatigue life and oxidation reaction rate;

[0037] Establish a performance change model, analyze the relationship between performance indicators and environmental conditions, and evaluate the impact of different environmental conditions and performance characteristics on the performance changes of injection molded parts.

[0038] As a further solution of the present invention, the performance change model is established, the relationship between the performance index and the environmental conditions is analyzed, and the influence of different environmental conditions and performance characteristics on the performance change of the injection molded parts is evaluated, specifically:

[0039] The performance change model is as follows:

[0040] ;

[0041] in, Represents comprehensive performance indicators, represents fatigue life, represents the fatigue limit, Indicates the degree of oxidation, is a constant term, expressed by the reaction rate, , , is the weight parameter;

[0042] ;

[0043] ;

[0044] ;

[0045] in, Indicates temperature, represents the temperature sensitivity coefficient, is the number of temperature cycles, is an index that indicates the influence of the number of temperature cycles on the fatigue limit. represents the oxidation impact index, represents the activation energy, that is, the energy required for the oxidation reaction, is the gas constant, is the temperature impact index, , , is a constant.

[0046] As a further solution of the present invention, the virtual experimental environment is constructed to simulate the performance of injection molded parts under different environmental conditions, and the durability, fatigue limit and oxidation risk of injection molded parts are evaluated in combination with the predicted results of performance changes, which specifically includes:

[0047] Based on the constructed temperature field, the real-time collected production environment data is input into the temperature field to build a virtual experimental environment;

[0048] Through the established performance change model, the injection molded parts in the current experimental environment are evaluated again.

[0049] Another object of the present invention is to provide a virtual detection and evaluation system for injection molding of automotive plastic parts, the system comprising:

[0050] Data collection and real-time monitoring module, used to obtain existing injection molding production data and collect real-time production environment data of the current injection molding site;

[0051] The temperature field model building and thermal analysis module is used to build a temperature field model to simulate the temperature changes and heat conduction experienced by injection molded parts during production and use, and to analyze the deformation, fatigue and oxidation reactions of injection molded parts in a high temperature environment, and to record the simulation and analysis results;

[0052] The performance change analysis module is used to extract performance characteristics from the recorded results, establish a performance change model, and predict the performance change of injection molded parts under different environmental conditions based on the extracted performance characteristics;

[0053] The virtual experiment and performance evaluation module is used to build a virtual experiment environment, simulate the performance of injection molded parts under different environmental conditions, and evaluate the durability, fatigue limit and oxidation risk of injection molded parts based on the predicted results of performance changes.

[0054] The beneficial effects of the present invention are:

[0055] This method can systematically evaluate the performance and reliability of injection molded parts under actual use conditions through precise thermal field simulation and stress analysis. In addition, the combination of fatigue theory and oxidation reaction analysis provides a scientific basis for predicting the service life and performance changes of materials, making the prediction results more accurate and reliable. This can not only effectively identify potential failure modes, but also provide data support for design optimization and material selection to improve product quality and durability. At the same time, the use of virtual detection technology reduces the cost and time of actual testing, improves R&D efficiency, and promotes the progress of intelligent manufacturing;

[0056] By using real-time environmental data, it is possible to dynamically adapt to changes in production conditions, making the evaluation results more timely and accurate. Based on the combination of temperature field models and performance change models, it is possible to more deeply analyze the specific impact of environmental factors on the performance of injection molded parts and predict more accurate product life and performance changes. In addition, performance evaluation through a virtual experimental environment reduces the need for actual samples, reduces experimental costs and time, and improves R&D efficiency. Timely identification of potential failure modes and performance degradation risks can propose improvement measures during the production stage, thereby improving the reliability and market competitiveness of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 A flowchart of a virtual detection and evaluation method for injection molding of automotive plastic parts provided by an embodiment of the present invention;

[0058] Figure 2 A flowchart for obtaining existing injection molding production data and collecting production environment data of the current injection molding site in real time provided by an embodiment of the present invention;

[0059] Figure 3 A flow chart for simulating the temperature change and heat conduction experienced by an injection molded part during production and use, and analyzing the deformation, fatigue, and oxidation reaction of the injection molded part in a high temperature environment, provided in an embodiment of the present invention;

[0060] Figure 4 A flow chart for predicting performance changes of injection molded parts under different environmental conditions based on the extracted performance characteristics provided by an embodiment of the present invention;

[0061] Figure 5 A flowchart for simulating the performance of injection molded parts under different environmental conditions provided in an embodiment of the present invention, and evaluating the durability, fatigue limit and oxidation risk of injection molded parts in combination with the predicted results of performance changes;

[0062] Figure 6 This is a structural block diagram of a virtual detection and evaluation system for injection molding of automotive plastic parts provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0064] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first xx script may be referred to as a second xx script, and similarly, a second xx script may be referred to as a first xx script.

[0065] Figure 1 The flowchart of the virtual detection and evaluation method for injection molding of automobile plastic parts provided by the embodiment of the present invention is as follows: Figure 1 As shown, a virtual detection and evaluation method for injection molding of automobile plastic parts comprises:

[0066] S100, obtaining existing injection molding production data and collecting production environment data of the current injection molding site in real time;

[0067] This step will extract records of each production batch from the production database, covering parameters such as injection temperature, pressure, injection time, cooling time, material batch, mold temperature, etc., to ensure the integrity and accuracy of the data. Next, the extracted data is preprocessed to clean redundant or erroneous data, supplement missing values, and standardize for subsequent analysis. At the same time, the physical and chemical properties data of the plastic materials used are collected, including melting temperature, density, thermal conductivity, tensile strength, fatigue strength, aging performance, etc., and the records of injection defects in historical data are summarized.

[0068] On this basis, sensors are installed at the production site to monitor environmental parameters such as temperature, humidity, air pressure, vibration, etc. in real time, and collect real-time operation data of injection molding machines. These real-time collected environmental data are integrated with historical injection molding production data, and data mining technology is used to analyze the relationship between temperature fluctuations, humidity changes, and production parameters to discover potential influencing factors and patterns.

[0069] By comprehensively analyzing historical and real-time data, we can more accurately understand and predict the performance of injection molded parts under different environmental conditions, providing empirical support for production decisions. By analyzing historical defect data, we can identify potential defect risks, implement early warning mechanisms, and adjust production processes in a timely manner to reduce the incidence of defects.

[0070] like Figure 2 As shown, the acquisition of existing injection molding production data and real-time collection of production environment data of the current injection molding site specifically includes:

[0071] S110, extracting past injection molding production records from a production database, including parameters of each production batch;

[0072] S120, collecting characteristic data of the plastic materials used and summarizing the records of injection molding defects in historical data;

[0073] S130 monitors the environmental parameters in the production process in real time, integrates the real-time collected environmental data with the historical injection molding production data, and analyzes the relationship between temperature fluctuations, humidity changes and production parameters.

[0074] S200, builds a temperature field model to simulate the temperature changes and heat conduction experienced by injection molded parts during production and use, analyzes the deformation, fatigue and oxidation reactions of injection molded parts in high temperature environments, and records the simulation and analysis results;

[0075] In this step, it is necessary to create a geometric model of the injection molded part and define the thermophysical properties of the plastic material used, such as thermal conductivity and specific heat capacity, to ensure the accuracy of the simulation.

[0076] Creating a geometric model of an injection molded part requires considering the mold shape, plastic flow path, cooling channels, etc. in order to perform an accurate heat transfer analysis.

[0077] Define the thermophysical properties of plastic materials, such as thermal conductivity, specific heat capacity, coefficient of thermal expansion, etc. These parameters may differ at high and low temperature conditions.

[0078] Thermophysical properties of plastic materials are defined in order to accurately simulate the thermal behavior of the material under temperature changes.

[0079] The thermal conductivity of the material affects its response to temperature changes, which in turn affects the thermal field distribution and performance of the entire injection molded part.

[0080] Next, the heat exchange boundary conditions between the injection molded part and the environment are determined, which includes defining the effects of heat convection and heat radiation in order to simulate the real production environment. At the same time, the initial temperature distribution of the injection molded part at the beginning of the simulation is set to reflect the state in the actual production environment.

[0081] The heat exchange boundary conditions between the injection molded part and the environment can be the cooling fluid temperature on the mold surface, the temperature of the surrounding environment, etc.

[0082] Boundary conditions define how heat is exchanged between the molded part and the environment, which is crucial to understanding and predicting the development of the temperature field.

[0083] The initial temperature distribution of the molded part at the beginning of the simulation is usually the temperature at the beginning of the injection molding process or the ambient temperature.

[0084] On this basis, the numerical simulation method is used to perform time-domain simulation of the temperature field of the created geometric model, analyze the temperature distribution of the injection molded parts at different time points, calculate the temperature changes inside and on the surface of the injection molded parts, and record the temperature distribution results in different time periods to obtain detailed temperature field data.

[0085] The purpose of creating a geometric model of an injection molded part is to accurately reflect the actual shape and size of the part. The geometric features of the injection molded part (such as wall thickness, concave and convex shape, etc.) will directly affect heat conduction and stress distribution.

[0086] An accurate geometric model helps capture the distribution of temperature variations in different areas, especially when there are complex shapes or details such as cooling channels, grooves, edges, etc.

[0087] Based on the simulation results of the temperature field, the thermal stress caused by temperature changes is further calculated to analyze the stress distribution of injection molded parts in high temperature environments. To this end, the thermal stress formula is used to comprehensively consider temperature changes, the thermal expansion coefficient and elastic modulus of the material to accurately evaluate the impact of thermal stress. In addition, the material fatigue theory is used to combine temperature and stress data to predict the fatigue life and fatigue limit of the material, which helps to evaluate the reliability of injection molded parts under actual working conditions. Finally, considering the relationship between the oxidation reaction rate and temperature and time, the oxidation process of the material at high temperature is simulated, and the changes in material properties caused by oxidation are recorded to fully understand the performance of injection molded parts in high temperature environments.

[0088] Through accurate thermal field simulation and stress analysis, the performance and reliability of injection molded parts under actual use conditions can be systematically evaluated. In addition, the combination of fatigue theory and oxidation reaction analysis provides a scientific basis for predicting the service life and performance changes of materials, making the prediction results more accurate and reliable. This can not only effectively identify potential failure modes, but also provide data support for design optimization and material selection to improve product quality and durability. At the same time, the use of virtual detection technology reduces the cost and time of actual testing, improves R&D efficiency, and promotes the progress of intelligent manufacturing.

[0089] like Figure 3 As shown, the simulation of the temperature change and heat conduction experienced by the injection molded parts during production and use, and the analysis of the deformation, fatigue and oxidation reaction of the injection molded parts in a high temperature environment, specifically include:

[0090] S210, creating a geometric model of the injection molded part and defining the thermophysical properties of the plastic material;

[0091] S220, determining the heat exchange boundary conditions between the injection molded part and the environment, and setting the initial temperature distribution of the injection molded part at the beginning of the simulation;

[0092] S230, based on the set conditions, perform a time domain simulation of the temperature field on the created injection molded part geometric model, analyze the temperature distribution of the injection molded part at different time points, calculate the temperature changes inside and on the surface of the injection molded part, and record the temperature distribution results in different time periods;

[0093] S240, based on the temperature field results, calculate the thermal stress caused by temperature change and analyze the stress distribution of injection molded parts in high temperature environment;

[0094] S250, using material fatigue theory, combined with temperature and stress data, predicts the fatigue life and fatigue limit of materials;

[0095] S260, considering the relationship between oxidation reaction rate, temperature and time, simulates the oxidation process of materials at high temperatures and records the changes in material properties caused by oxidation.

[0096] In this embodiment, the thermal stress generated by temperature change is calculated based on the temperature field result, specifically:

[0097] ;

[0098] Where, is the final thermal stress value, is the mechanical stress caused by external loads or constraints, is the theoretical thermal stress;

[0099] ;

[0100] in, is the elastic modulus of the material, is the current thermal expansion coefficient of the material, is the temperature change value.

[0101] In this embodiment, the predicting of the fatigue life of the material specifically includes:

[0102] ;

[0103] in, represents fatigue life, Display material The stress amplitude, is the material constant;

[0104] ;

[0105] in, are the maximum and minimum stresses of a material under cyclic loading.

[0106] In this embodiment, the fatigue limit prediction includes:

[0107] ;

[0108] in, represents the fatigue limit, represents the mean stress, Represents tensile strength, Represents the stress amplitude.

[0109] S300, extracting performance characteristics from the recorded results, establishing a performance change model, and predicting performance changes of the injection molded parts under different environmental conditions based on the extracted performance characteristics;

[0110] This step requires the identification of key indicators that affect the performance of injection molded parts, including the number of temperature cycles, fatigue limit, fatigue life, and oxidation reaction rate. By defining and quantifying these indicators, the foundation can be laid for subsequent performance change analysis. Next, a performance change model is established to analyze the relationship between performance indicators and environmental conditions. The model will simulate and statistically analyze the performance of injection molded parts under different environmental conditions to evaluate the impact of different environmental factors (such as temperature, humidity, pressure, etc.) and performance characteristics on the performance changes of injection molded parts.

[0111] Specifically, the establishment of the performance change model can adopt statistical methods such as multivariate regression analysis, and incorporate indicators such as the number of temperature cycles, fatigue limit, fatigue life and oxidation reaction rate into the model to form a comprehensive performance index. By optimizing and debugging the model parameters, the influence of environmental conditions on the performance of injection molded parts can be more accurately reflected. At the same time, the comparison of the prediction results with the experimental data is combined to verify the effectiveness and accuracy of the model to ensure its adaptability. This method not only improves the accuracy of performance prediction, but also provides a scientific basis for material selection and product design, helping engineers to foresee potential failure modes in the design stage. In addition, the establishment of the performance change model provides a solid data foundation for subsequent virtual experiments, which can effectively reduce the cost and time of actual testing and improve overall R&D efficiency. The application of this methodology will provide more accurate guidance for the design and production of automotive plastic parts, promote the process of intelligent manufacturing and digital transformation, and enhance the competitiveness of products in the market. Through detailed analysis of material fatigue and oxidation reactions, it is helpful to improve the durability and reliability of products, so as to better meet the needs of the market and users.

[0112] This method not only improves the accuracy of performance prediction, but also provides a scientific basis for material selection and product design, helping engineers to foresee potential failure modes in the design stage. In addition, the establishment of the performance change model provides a solid data foundation for subsequent virtual experiments, which can effectively reduce the cost and time of actual testing and improve overall R&D efficiency. The application of this methodology will provide more accurate guidance for the design and production of automotive plastic parts, promote the process of intelligent manufacturing and digital transformation, and enhance the competitiveness of products in the market. Detailed analysis of material fatigue and oxidation reactions can help improve the durability and reliability of products, thereby better meeting the needs of the market and users.

[0113] like Figure 4 As shown, the performance change model is established to predict the performance change of the injection molded parts under different environmental conditions based on the extracted performance characteristics, specifically including:

[0114] S310, defines the performance indicators that affect injection molded parts, including the number of temperature cycles, fatigue limit, fatigue life, and oxidation reaction rate;

[0115] S320, establish a performance change model, analyze the relationship between performance indicators and environmental conditions, and evaluate the impact of different environmental conditions and performance characteristics on the performance changes of injection molded parts.

[0116] In this embodiment, the performance change model is established, the relationship between the performance index and the environmental conditions is analyzed, and the influence of different environmental conditions and performance characteristics on the performance change of the injection molded parts is evaluated, specifically:

[0117] The performance change model is as follows:

[0118] ;

[0119] in, Represents comprehensive performance indicators, represents fatigue life, represents the fatigue limit, Indicates the degree of oxidation, is a constant term, expressed by the reaction rate, , , is the weight parameter;

[0120] ;

[0121] ;

[0122] ;

[0123] in, Indicates temperature, represents the temperature sensitivity coefficient, is the number of temperature cycles, is an index that indicates the influence of the number of temperature cycles on the fatigue limit. represents the oxidation impact index, represents the activation energy, that is, the energy required for the oxidation reaction, is the gas constant, is the temperature impact index, , , is a constant.

[0124] S400 builds a virtual experimental environment to simulate the performance of injection molded parts under different environmental conditions, and combines the predicted results of performance changes to evaluate the durability, fatigue limit and oxidation risk of injection molded parts.

[0125] In this step, the real-time production environment data (such as temperature, humidity, pressure, etc.) collected in step S100 is first input into the constructed temperature field model. These data should be collected in real time through sensors, and their accuracy and reliability should be ensured. Next, according to the input real-time environmental data, the parameters of the temperature field model are adjusted, and the initial temperature distribution and boundary conditions of the injection molded parts are updated in real time according to the current ambient temperature changes, so that the model reflects the current actual production status. On this basis, a virtual experimental environment is created to simulate the heat conduction process of the injection molded parts under real-time environmental conditions.

[0126] After completing the construction of the virtual experimental environment, the previously established performance change model is used to evaluate the performance of the current injection molded parts. By analyzing temperature changes, oxidation reactions and other environmental factors, the durability, fatigue limit and oxidation risk of the injection molded parts are evaluated, and the simulation results are used to calculate the possible fatigue life and failure mode to identify potential performance degradation risks. In addition, the results of the simulation evaluation are recorded and compared with historical data to verify the effectiveness of the model. At the same time, a feedback mechanism is formed to feed the evaluation results back to the production process to guide the optimization of production parameters.

[0127] By using real-time environmental data, it is possible to dynamically adapt to changes in production conditions, making the evaluation results more timely and accurate. Based on the combination of temperature field models and performance change models, it is possible to more deeply analyze the specific impact of environmental factors on the performance of injection molded parts and predict more accurate product life and performance changes. In addition, performance evaluation through a virtual experimental environment reduces the need for actual samples, reduces experimental costs and time, and improves R&D efficiency. Timely identification of potential failure modes and performance degradation risks can propose improvement measures during the production stage, thereby improving the reliability and market competitiveness of the final product.

[0128] like Figure 5 As shown, the virtual experimental environment is constructed to simulate the performance of injection molded parts under different environmental conditions, and combined with the predicted results of performance changes, the durability, fatigue limit and oxidation risk of the injection molded parts are evaluated, specifically including:

[0129] S410, based on the constructed temperature field, inputting the real-time collected production environment data into the temperature field to build a virtual experimental environment;

[0130] S420, the injection molded parts in the current experimental environment are evaluated again through the established performance change model.

[0131] Figure 6 The structure block diagram of the virtual detection and evaluation system for injection molding of automobile plastic parts provided by the embodiment of the present invention is as follows: Figure 6 As shown, the system comprises:

[0132] The data acquisition and real-time monitoring module 100 is used to obtain existing injection molding production data and collect the production environment data of the current injection molding site in real time;

[0133] The temperature field model building and thermal analysis module 200 is used to build a temperature field model, simulate the temperature change and heat conduction experienced by the injection molded parts during production and use, analyze the deformation, fatigue and oxidation reaction of the injection molded parts in a high temperature environment, and record the simulation and analysis results;

[0134] The performance change analysis module 300 is used to extract performance characteristics from the recorded results, establish a performance change model, and predict the performance change of the injection molded parts under different environmental conditions based on the extracted performance characteristics;

[0135] The virtual experiment and performance evaluation module 400 is used to build a virtual experiment environment, simulate the performance of injection molded parts under different environmental conditions, and evaluate the durability, fatigue limit and oxidation risk of injection molded parts in combination with the predicted results of performance changes.

[0136] It should be understood that, although each step in the flow chart of each embodiment of the present invention is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0137] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0138] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

[0140] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A virtual inspection and evaluation method for injection molding of automotive plastic parts, characterized in that: The method comprises: Acquire existing injection molding production data and collect the production environment data of the current injection molding site in real time; Construct a temperature field model to simulate the temperature changes and heat conduction experienced by injection molded parts during production and use, analyze the deformation, fatigue and oxidation reactions of injection molded parts in high temperature environments, and record the simulation and analysis results; Extract performance characteristics from the recorded results, establish a performance change model, and predict the performance changes of injection molded parts under different environmental conditions based on the extracted performance characteristics; Build a virtual experimental environment to simulate the performance of injection molded parts under different environmental conditions, and combine the predicted results of performance changes to evaluate the durability, fatigue limit and oxidation risk of injection molded parts.

2. The method according to claim 1, characterized in that The acquisition of existing injection molding production data and real-time collection of production environment data of the current injection molding site specifically includes: Extract past injection molding production records from the production database, including the parameters of each production batch; Collect the characteristic data of the plastic materials used and summarize the records of injection molding defects in historical data; Monitor environmental parameters during the production process in real time, integrate the real-time collected environmental data with historical injection molding production data, and analyze the relationship between temperature fluctuations, humidity changes and production parameters.

3. The method according to claim 2, characterized in that The simulation of the temperature change and heat conduction experienced by the injection molded parts during production and use, and the analysis of the deformation, fatigue and oxidation reaction of the injection molded parts in a high temperature environment, specifically include: Create geometric models of injection molded parts and define the thermophysical properties of plastic materials; Determine the heat exchange boundary conditions between the injection molded part and the environment, and set the initial temperature distribution of the injection molded part at the beginning of the simulation; Based on the set conditions, the temperature field time domain simulation is performed on the created injection molded part geometric model, the temperature distribution of the injection molded part at different time points is analyzed, the temperature changes inside and on the surface of the injection molded part are calculated, and the temperature distribution results in different time periods are recorded; Based on the temperature field results, calculate the thermal stress caused by temperature changes and analyze the stress distribution of injection molded parts in high temperature environments; Use material fatigue theory, combined with temperature and stress data, to predict the fatigue life and fatigue limit of materials; Considering the relationship between oxidation reaction rate, temperature and time, the oxidation process of materials at high temperature is simulated, and the changes in material properties caused by oxidation are recorded.

4. The method according to claim 3, characterized in that The thermal stress generated by temperature change is calculated based on the temperature field results, specifically: ； in, is the final thermal stress value, is the mechanical stress caused by external loads or constraints, is the theoretical thermal stress; ； in, is the elastic modulus of the material, is the current thermal expansion coefficient of the material, is the temperature change value.

5. The method according to claim 4, characterized in that The predicted material fatigue life specifically includes: ； in, represents fatigue life, Display material The stress amplitude, is the material constant; ； in, represents the stress amplitude of the material, are the maximum and minimum stresses of a material under cyclic loading.

6. The method according to claim 5, characterized in that The fatigue limit prediction includes: ； in, represents the fatigue limit, represents the mean stress, Represents tensile strength, Represents the stress amplitude.

7. The method according to claim 6, characterized in that The performance change model is established to predict the performance change of the injection molded parts under different environmental conditions based on the extracted performance characteristics, specifically including: Define the performance indicators that affect injection molded parts, including temperature cycle number, fatigue limit, fatigue life and oxidation reaction rate; Establish a performance change model, analyze the relationship between performance indicators and environmental conditions, and evaluate the impact of different environmental conditions and performance characteristics on the performance changes of injection molded parts.

8. The method according to claim 7, characterized in that The performance change model is established to analyze the relationship between performance indicators and environmental conditions, and to evaluate the influence of different environmental conditions and performance characteristics on the performance change of injection molded parts, specifically: The performance change model is as follows: ； in, Represents comprehensive performance indicators, represents fatigue life, represents the fatigue limit, Indicates the degree of oxidation, is a constant term, expressed by the reaction rate, , , is the weight parameter; ； ； ； in, Indicates temperature, represents the temperature sensitivity coefficient, Indicates the number of temperature cycles, is an index that indicates the influence of the number of temperature cycles on the fatigue limit. represents the oxidation impact index, represents the activation energy, that is, the energy required for the oxidation reaction, is the gas constant, is the temperature impact index, , , is a constant.

9. The method according to claim 8, characterized in that The virtual experimental environment is built to simulate the performance of injection molded parts under different environmental conditions, and combined with the predicted results of performance changes, the durability, fatigue limit and oxidation risk of injection molded parts are evaluated, including: Based on the constructed temperature field, the real-time collected production environment data is input into the temperature field to build a virtual experimental environment; Through the established performance change model, the injection molded parts in the current experimental environment are evaluated again.

10. A virtual inspection and evaluation system for injection molding of automotive plastic parts, characterized in that: The system comprises: Data collection and real-time monitoring module, used to obtain existing injection molding production data and collect real-time production environment data of the current injection molding site; The temperature field model building and thermal analysis module is used to build a temperature field model to simulate the temperature changes and heat conduction experienced by injection molded parts during production and use, and to analyze the deformation, fatigue and oxidation reactions of injection molded parts in a high temperature environment, and to record the simulation and analysis results; The performance change analysis module is used to extract performance characteristics from the recorded results, establish a performance change model, and predict the performance change of injection molded parts under different environmental conditions based on the extracted performance characteristics; The virtual experiment and performance evaluation module is used to build a virtual experiment environment, simulate the performance of injection molded parts under different environmental conditions, and evaluate the durability, fatigue limit and oxidation risk of injection molded parts based on the predicted results of performance changes.

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