A method and system for predicting the life of stamping dies based on numerical analysis

Abstract

This application provides a numerical analysis-based method and system for predicting the life of stamping dies, relating to the field of stamping die life prediction technology. The key technical points are: adjusting multiple mesh nodes based on cumulative damage distribution information to obtain the current cutting edge region of the stamping die; determining the interaction region through the current cutting edge region of the stamping die; distributing loads in the interaction region based on stamping load parameters to obtain load distribution results; obtaining stress distribution information based on the load distribution results; determining the current damage increment based on the stress distribution information; adjusting the cumulative damage information based on the differences between multiple mesh nodes before and after adjustment; obtaining the current cumulative damage information based on the adjusted cumulative damage information and the current damage increment; and predicting the remaining service life of the stamping die based on the current cumulative damage information. This application aims to improve the accuracy of load distribution and stress analysis to achieve accurate prediction of the remaining service life of stamping dies.

Description

Technical Field

[0001] This application relates to the field of stamping die life prediction technology, and more specifically, to a method and system for predicting stamping die life based on numerical analysis. Background Technology

[0002] In the prediction of stamping die life, numerical analysis models typically calculate damage accumulation based on initial cutting edge geometry and contact boundary conditions. However, in continuous high-speed stamping mass production, the die cutting edge undergoes progressive micro-wear, leading to subtle changes in the contact initiation position, contact area, and friction distribution. The numerical analysis model, still relying on the initial boundary rolling prediction, fails to update synchronously, causing a misalignment between the physical state and the logical model. This results in the peak contact pressure position being incorrectly retained in the old region, local stress concentrations being shifted or weakened, and subsequent fatigue and wear coupling calculations accumulating damage along the erroneous boundary. The damage growth rhythm gradually deviates from the actual state, affecting the predicted remaining die life. Summary of the Invention

[0003] The purpose of this application is to provide a method and system for predicting the life of stamping dies based on numerical analysis, which aims to improve the accuracy of load distribution and stress analysis, so as to achieve accurate prediction of the remaining service life of stamping dies.

[0004] In a first aspect, this application provides a numerical analysis-based method for predicting the life of stamping dies, applied to a die model of the stamping die. The die model stores and manages die data, including a three-dimensional model of the stamping die, geometric parameters, and material property parameters. The numerical analysis-based method for predicting the life of stamping dies includes: Obtain the current service status information of the stamping die, which includes stamping load parameters and cumulative damage distribution information of the cutting edge area of ​​the stamping die. The cutting edge area of ​​the stamping die includes multiple grid nodes, and the cumulative damage distribution information includes the cumulative damage information corresponding to each grid node. Based on the cumulative damage distribution information, the multiple mesh nodes are adjusted, and the geometric representation parameters of the stamping die cutting edge region are adjusted through the adjusted multiple mesh nodes to obtain the current stamping die cutting edge region. The interaction region between the stamping die and the workpiece is determined through the current stamping die cutting edge region. Based on the stamping load parameters, load distribution is performed in the interaction region to obtain load distribution results. Based on the load distribution results, stress distribution information of the current stamping die cutting edge region is obtained. Based on the stress distribution information, the current damage increment of the current stamping die cutting edge area is determined. Based on the difference between multiple mesh nodes before and after adjustment, the cumulative damage information is adjusted. Based on the adjusted cumulative damage information and the current damage increment, the current cumulative damage information is obtained. Based on the current cumulative damage information, the remaining service life of the stamping die is predicted.

[0005] Further, adjusting the plurality of grid nodes based on the cumulative damage distribution information includes: Based on the topological relationships around each of the grid nodes, the weighted average inner normal vector of each of the grid nodes is obtained; The wear depth of each mesh node is determined based on the cumulative damage information of each mesh node, and the coordinates of each mesh node are adjusted along the weighted average inner normal vector of each mesh node based on the wear depth of each mesh node.

[0006] Furthermore, after adjusting the multiple grid nodes based on the cumulative damage distribution information, the numerical analysis-based method for predicting the life of stamping dies further includes: Perform mesh quality verification on multiple adjusted mesh nodes to determine the degree of distortion of each mesh node; If the distortion of at least one mesh node exceeds a preset distortion threshold, a local re-division region is defined centered on the mesh node whose distortion exceeds the preset distortion threshold. The boundaries of the mesh nodes whose distortion does not exceed the distortion threshold and the boundaries of the current stamping die cutting edge region are used as constraints to re-divide the mesh nodes in the local re-division region to update the adjusted multiple mesh nodes.

[0007] Further, the process of obtaining a load distribution result based on the stamping load parameters in the interaction region includes: Within the interaction region, the load distribution of the stamping load parameters is iteratively calculated using a finite element solver and a preset mechanical analysis algorithm until the preset mechanical equilibrium condition and preset interaction coordination condition are met, thus obtaining the load distribution result.

[0008] Further, obtaining the stress distribution information of the current stamping die cutting edge region based on the load distribution result includes: Update the material properties of each mesh node based on the cumulative damage information of each mesh node; Based on the updated material properties and load distribution results of each mesh node, the stress tensor components, equivalent stress, and hydrostatic stress of each mesh node in the current stamping die cutting edge region are output through the Newton-Raphson iteration of the finite element solver, thereby obtaining the stress distribution information of the current stamping die cutting edge region.

[0009] Furthermore, the current damage increment includes wear damage increment and fatigue damage increment, the cumulative damage information includes cumulative wear damage information and cumulative fatigue damage information, and the current cumulative damage information includes current cumulative wear damage information and current cumulative fatigue damage information.

[0010] Furthermore, the numerical analysis-based method for predicting the life of stamping dies also includes: Obtain the surface physical structure information of the current stamping die cutting edge area, and obtain the surface physical thickness based on the cumulative wear damage information and surface physical structure information of the current stamping die cutting edge area; If the physical thickness of the surface is less than a preset thickness threshold, the current cumulative fatigue damage information is reduced, and the reduced current cumulative fatigue damage information is stored in the mold model to be used as cumulative fatigue damage information in the next calculation of the current cumulative fatigue damage information.

[0011] Furthermore, adjusting the cumulative damage information based on the differences between multiple mesh nodes before and after the adjustment includes: Extract the cumulative damage information, node coordinates, and shape functions of the unadjusted mesh nodes within the local re-division region. Establish a set of node equations based on the node coordinates and shape functions of the unadjusted mesh nodes within the local re-division region. Calculate the set of node equations using a preset transformation algorithm to obtain the node coordinates of the adjusted mesh nodes within the local re-division region. Based on the cumulative damage information of the unadjusted mesh nodes in the local re-division region, the cumulative damage information of the adjusted mesh nodes in the local re-division region is obtained by interpolation calculation using the shape function with the node coordinates of the adjusted mesh nodes in the local re-division region as weights.

[0012] Further, the step of obtaining the cumulative damage information of the adjusted mesh nodes in the local re-division region by interpolating using the shape function with the node coordinates of the adjusted mesh nodes in the local re-division region as weights, based on the cumulative damage information of the unadjusted mesh nodes in the local re-division region, includes: Based on the cumulative damage information and node coordinates of the mesh nodes before adjustment within the local re-division region, calculate the damage gradient vector; When the magnitude of the damage gradient vector is not greater than a preset magnitude threshold, the cumulative damage information of the adjusted mesh nodes in the local re-division region is obtained by interpolation calculation using the shape function with the node coordinates of the adjusted mesh nodes in the local re-division region as weights. When the magnitude of the damage gradient vector is greater than the preset magnitude threshold, the cumulative damage information of the unadjusted mesh nodes in the largest local repartition region is taken as the extreme control point. Based on the extreme control point, the topological distance coefficient between the node coordinates of the adjusted mesh nodes in the local repartition region and the extreme control point is calculated. Based on the topological distance coefficient, a modified shape function including a distance attenuation term is established. The cumulative damage information of the adjusted mesh nodes in the local repartition region is calculated through the modified shape function.

[0013] Secondly, this application provides a numerical analysis-based stamping die life prediction system, applied to a die model of the stamping die. The die model stores and manages die data including a three-dimensional model of the stamping die, geometric parameters, and material property parameters. The numerical analysis-based stamping die life prediction system includes: The information acquisition module is used to acquire the current service status information of the stamping die. The current service status information includes stamping load parameters and cumulative damage distribution information of the cutting edge area of ​​the stamping die. The cutting edge area of ​​the stamping die includes multiple grid nodes, and the cumulative damage distribution information includes the cumulative damage information corresponding to each grid node. The geometry adjustment module is used to adjust the multiple mesh nodes based on the cumulative damage distribution information, and adjust the geometric representation parameters of the stamping die cutting edge region through the adjusted multiple mesh nodes to obtain the current stamping die cutting edge region, and determine the interaction region between the stamping die and the workpiece through the current stamping die cutting edge region; The stress analysis module is used to perform load distribution in the interaction region based on the stamping load parameters to obtain load distribution results, and to obtain stress distribution information of the current stamping die cutting edge region based on the load distribution results; The damage assessment module is used to determine the current damage increment of the cutting edge area of ​​the current stamping die based on the stress distribution information, adjust the cumulative damage information based on the difference of multiple mesh nodes before and after adjustment, and obtain the current cumulative damage information based on the adjusted cumulative damage information and the current damage increment. The life prediction module is used to predict the remaining service life of the stamping die based on the current cumulative damage information.

[0014] As can be seen from the above, the numerical analysis-based method for predicting the life of stamping dies provided in this application maintains a high degree of consistency with the actual micro-wear state by dynamically updating the geometric representation parameters of the die cutting edge region. This allows for a more accurate determination of the interaction area between the stamping die and the workpiece, thereby improving the accuracy of load distribution and stress analysis. It also avoids the translation or weakening of local stress concentration phenomena, enabling subsequent fatigue and wear coupling calculations to continuously accumulate damage along a more realistic boundary. Consequently, it can output a damage growth rhythm that better matches the actual state, improving the accuracy and reliability of rolling prediction of the remaining life of stamping dies. Attached Figure Description

[0015] Figure 1 This is a flowchart of a numerical analysis-based method for predicting the life of stamping dies provided in one embodiment of this application; Figure 2 This is a flowchart of a method for predicting the life of stamping dies based on numerical analysis provided in another embodiment of this application; Figure 3 This is a flowchart of a method for predicting the life of stamping dies based on numerical analysis, provided in another embodiment of this application. Detailed Implementation

[0016] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. The components of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0017] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0018] like Figure 1 As shown, Figure 1 This is a flowchart of a numerical analysis-based method for predicting the life of stamping dies provided in one embodiment of this application. The method can be applied to a die model of a stamping die. The die model is used to store and manage die data, including the three-dimensional model of the stamping die, geometric parameters, and material property parameters. The method may include, but is not limited to, steps S110 to S150.

[0019] Step S110: Obtain the current service status information of the stamping die. The current service status information includes stamping load parameters and cumulative damage distribution information of the cutting edge area of ​​the stamping die. The cutting edge area of ​​the stamping die includes multiple grid nodes, and the cumulative damage distribution information includes the cumulative damage information of each corresponding grid node. Step S120: Based on the cumulative damage distribution information, adjust multiple mesh nodes, and adjust the geometric representation parameters of the stamping die cutting edge region through the adjusted multiple mesh nodes to obtain the current stamping die cutting edge region. Determine the interaction region between the stamping die and the workpiece through the current stamping die cutting edge region. Step S130: Based on the stamping load parameters, load distribution is performed in the interaction region to obtain the load distribution result. Based on the load distribution result, the stress distribution information of the current stamping die cutting edge region is obtained. Step S140: Based on the stress distribution information, determine the current damage increment of the current stamping die cutting edge area. Based on the differences between multiple mesh nodes before and after adjustment, adjust the cumulative damage information. Based on the adjusted cumulative damage information and the current damage increment, obtain the current cumulative damage information. Step S150: Based on the current cumulative damage information, predict the remaining service life of the stamping die.

[0020] For example, the numerical analysis-based method for predicting the life of stamping dies provided in this application can be applied to the die model of a stamping die. A stamping die is a tool used to form a workpiece during the stamping process. The die model is used to store and manage the three-dimensional geometry, material properties, and other relevant data of the stamping die and can perform data analysis. The method obtains the current service status information of the stamping die, which refers to real-time or near-real-time data of the stamping die under actual working conditions. This includes stamping load parameters and cumulative damage distribution information of the die cutting edge region. The die cutting edge region is the area where the die directly contacts the workpiece and bears the main load. The die cutting edge region includes multiple grid nodes, each corresponding to cumulative damage information to characterize the degree of damage suffered during service.

[0021] For example, the current service status information of a stamping die can be obtained by real-time monitoring of the stamping press's operating parameters using sensors, such as stamping force, stamping speed, and stroke, as stamping load parameters. Simultaneously, non-destructive testing can be used to obtain the geometric morphology data of the die's cutting edge region. This data, combined with historical damage data or image processing techniques, can be used to analyze the microscopic changes on the cutting edge surface, thereby obtaining the cumulative damage information for each grid node in the cutting edge region. Furthermore, a monitoring cycle can be pre-set, and at the end of each cycle, the die can be inspected offline to obtain its current service status information. For instance, after a certain number of stamping cycles, a high-precision 3D scanner can be used to scan the cutting edge region, obtaining the current geometric morphology. This data, combined with historical damage data stored in the die model, can then be used to calculate the cumulative damage information for each grid node.

[0022] Based on the acquired cumulative damage distribution information, multiple mesh nodes need to be adjusted. These adjusted mesh nodes are then used to adjust the geometric representation parameters of the stamping die cutting edge region, thus obtaining the current stamping die cutting edge region. For example, the wear depth of each mesh node can be calculated based on its cumulative damage information, and then the node coordinates can be fine-tuned along the node's normal direction. The adjusted set of mesh nodes more accurately represents the actual geometric morphology of the stamping die cutting edge region. Using the adjusted mesh nodes, the three-dimensional geometric model of the stamping die cutting edge region can be reconstructed or updated to obtain the current stamping die cutting edge region. Subsequently, the interaction area between the stamping die and the workpiece can be determined using the current stamping die cutting edge region. For example, a geometric intersection algorithm can be used to calculate the contact area between the current stamping die cutting edge region and the workpiece's three-dimensional model during the stamping process; this is the interaction area.

[0023] After determining the interaction region, the finite element method (FEM) can be used to apply stamping load parameters to the interaction region. By solving the mechanical equilibrium equations, the stress distribution information of each die cutting edge region within the interaction region can be obtained. For example, based on the load distribution results, combined with the geometric model and material properties of the current die cutting edge region, stress analysis can be performed using a finite element solver to output the stress tensor components, equivalent stress, and hydrostatic stress of each mesh node, thereby obtaining the stress distribution information of the current die cutting edge region. Subsequently, based on the stress distribution information and a preset damage evolution model, the amount of damage added to each mesh node in the current stamping cycle can be calculated. At the same time, based on the differences between multiple mesh nodes before and after adjustment, the cumulative damage information needs to be adjusted. That is, if the position of a mesh node changes, the corresponding cumulative damage information also needs to be interpolated or mapped accordingly to ensure the continuity and accuracy of the damage information.

[0024] Based on the current cumulative damage information, the remaining service life of the stamping die can be predicted. This can be done by setting a total damage threshold. When the current cumulative damage information of any grid node reaches the threshold, the die is considered to have reached the end of its service life. By calculating the distance between the current cumulative damage information and the total damage threshold, and combining this with the damage growth rate, it is possible to predict how many stamping cycles the die can withstand, i.e., its remaining service life.

[0025] It is understood that the stamping die life prediction method provided in this application dynamically acquires the current service status information of the stamping die and adjusts the geometric representation parameters of the die cutting edge region based on the cumulative damage distribution information, thereby obtaining the current stamping die cutting edge region. This method can characterize the micro-wear that occurs on the die cutting edge during service in real time and update the interaction region between the die and the workpiece, ensuring that the interaction region between the stamping die and the workpiece accurately represents the actual contact situation, thus avoiding prediction deviations caused by discrepancies between the geometric model and the actual state. Subsequently, load distribution and stress analysis are performed based on the updated interaction region, which ensures the accuracy of local stress calculation, more accurately determines the current damage increment, and updates the cumulative damage information, ultimately achieving an accurate prediction of the remaining service life of the stamping die and improving the accuracy and reliability of stamping die life prediction.

[0026] In a numerical analysis-based method for predicting the life of stamping dies provided in one embodiment of this application, step S120 may include, but is not limited to, steps S210 to S220.

[0027] Step S210: Based on the topological relationships around each grid node, obtain the weighted average inner normal vector of each grid node; Step S220: Determine the wear depth of each grid node based on the cumulative damage information of each grid node, and adjust the coordinates of each grid node according to the weighted average inner normal vector of each grid node based on the wear depth of each grid node.

[0028] For example, the topological relationships around a mesh node can be the connection relationships between each mesh node and its adjacent mesh nodes, used to define the local mesh geometry. By analyzing the topological relationships around a mesh node, the local surface orientation at each mesh node can be accurately calculated. The weighted average inner normal vector can be the normal direction pointing inwards to the mold, calculated by weighting the local surface orientation of each mesh node and its surrounding nodes. The weighted average inner normal vector can smooth local geometric features and reduce errors caused by mesh discretization, thus more accurately representing the actual normal direction of the mold surface.

[0029] The wear depth of each grid node is determined based on the cumulative damage information corresponding to each grid node. The wear depth can be calculated using a preset damage-wear model or empirical formula based on the cumulative damage information of each grid node, representing the thickness of material removed at that node. In some embodiments, a mapping relationship can be established between the wear depth and the cumulative damage information; when the cumulative damage reaches a certain threshold, the corresponding wear depth increases. Based on the wear depth of each grid node, the coordinates of each grid node are adjusted along the weighted average inner normal vector of each grid node, that is, each grid node is moved a distance equal to its wear depth along the direction of the calculated weighted average inner normal vector. In this way, the geometry of the die cutting edge region is updated to characterize the material loss caused by wear.

[0030] For example, this application embodiment can accurately capture the local geometric features of the die cutting edge region by analyzing the topological relationships around each grid node. By considering the topological relationships of the grid nodes and the weighted average internal normal vector, the accuracy of the wear direction can be ensured, avoiding local errors that may be caused by a single normal vector. Subsequently, the actual wear depth is quantified based on the cumulative damage information corresponding to each grid node, making the wear amount closely related to the actual service state of the die. Then, by adjusting the coordinates of each grid node along the weighted average internal normal vector with the corresponding wear depth as the displacement, the physical accuracy of the geometry of the stamping die cutting edge region is achieved. This can directly simulate the actual wear process of the material, providing a more realistic geometric model for subsequent load distribution and stress analysis, thereby improving the accuracy of life prediction.

[0031] In some embodiments described above, this application proposes adjusting multiple mesh nodes based on cumulative damage distribution information to characterize the wear condition of the stamping die cutting edge region. However, adjusting the mesh nodes may lead to a decrease in mesh quality or even mesh distortion, thereby affecting the accuracy and computational efficiency of subsequent mechanical analysis. If these problems are not addressed, inaccurate stress distribution calculations may occur, affecting the prediction accuracy of the remaining service life of the stamping die, and potentially leading to premature die failure or excessive scrapping.

[0032] In a numerical analysis-based method for predicting the life of stamping dies provided in one embodiment of this application, regarding the above step S120, after adjusting multiple grid nodes based on cumulative damage distribution information, steps S310 to S320 may also be included, but are not limited to.

[0033] Step S310: Perform mesh quality verification on the adjusted mesh nodes to determine the degree of distortion of each mesh node; Step S320: When the distortion degree of at least one mesh node exceeds the preset distortion threshold, a local re-division region is divided with the mesh node whose distortion degree exceeds the preset distortion threshold as the center, and the boundary of the mesh node whose distortion degree does not exceed the distortion threshold and the boundary of the current stamping die cutting edge region are used as constraints to re-divide the mesh nodes in the local re-division region to update the multiple mesh nodes after adjustment.

[0034] For example, mesh quality verification can be performed on multiple adjusted mesh nodes by checking the geometry and topology of the adjusted mesh nodes to assess whether they meet the requirements of finite element analysis and to determine the degree of distortion of each mesh node. The degree of distortion can be the degree to which the mesh element deviates from the ideal shape. For example, for triangular or quadrilateral meshes, the degree of distortion can be quantified by calculating parameters such as the Jacobian determinant, aspect ratio, and angle of the element.

[0035] If the distortion of at least one mesh node exceeds a preset distortion threshold, a local re-division region is defined centered on the mesh node whose distortion exceeds the preset distortion threshold. The local re-division region extends outward from the distorted mesh node to a certain extent, and the boundary of the region can be constrained by the boundary of the mesh node whose distortion does not exceed the distortion threshold and the overall boundary of the current stamping die cutting edge region, so as to ensure the locality of the re-division and avoid unnecessary global re-division of the entire die model.

[0036] Understandably, when mesh nodes undergo significant displacement due to wear adjustment, surrounding mesh elements may be stretched or compressed, resulting in irregular shapes and affecting the accuracy of finite element analysis. This application's embodiment introduces a mesh quality verification and local re-meshing mechanism. By verifying the quality of the adjusted mesh, distortion can be detected and quantified in a timely manner. When the distortion exceeds a preset threshold, local areas requiring optimization are identified and targeted mesh re-meshing is performed. This avoids time-consuming and resource-intensive global re-meshing of the entire mold model, while ensuring the mesh quality of critical areas. This provides a reliable geometric basis for subsequent stress analysis and damage assessment, improving the overall efficiency and practicality of the stamping die life prediction method.

[0037] In some embodiments, after adjusting multiple mesh nodes based on cumulative damage distribution information, if the Jacobian determinant of a local mesh cell in the die cutting edge region is detected to be less than a preset threshold, it indicates that the mesh cell has severe distortion. In this case, the distorted mesh node can be used as the center, expanding outwards. For example, its two adjacent layers of mesh nodes can be used as a local re-division region. Simultaneously, the boundaries of the undistorted mesh nodes surrounding the local re-division region and the overall boundary of the die cutting edge region can be used as geometric constraints. An adaptive mesh generation algorithm can then be used to regenerate high-quality mesh nodes for this local region. Delaunay triangulation or quadrilateral mesh generation algorithms can be employed to ensure that the newly generated mesh cells meet quality standards such as minimum angle and maximum aspect ratio.

[0038] In one embodiment of the numerical analysis-based method for predicting the life of stamping dies provided in this application, step S130 may include, but is not limited to, step S410.

[0039] Step S410: Within the interaction region, iterative calculations of the load distribution of stamping load parameters are performed using a finite element solver and a preset mechanical analysis algorithm until the preset mechanical equilibrium conditions and preset interaction coordination conditions are met, thus obtaining the load distribution results.

[0040] For example, the interaction region refers to the area where the stamping die and the workpiece come into contact and transfer loads during the stamping process. Within the interaction region, the distribution of stamping load parameters is crucial for the stress analysis of the die. Therefore, the load distribution of stamping load parameters can be iteratively calculated using a finite element solver and a preset mechanical analysis algorithm. The finite element solver performs numerical calculations based on the finite element method, which can discretize complex continuums into a finite number of elements and simulate the overall structural response through mechanical analysis. The preset mechanical analysis algorithm can be a mathematical model and calculation rule implemented in the finite element solver to describe material constitutive relations, contact friction models, and load transfer mechanisms, such as an elastoplastic constitutive model or a Coulomb friction model.

[0041] Then, through iterative calculations, the load distribution is corrected in each iteration to conform to the actual physical conditions until the preset mechanical equilibrium conditions and preset interaction coordination conditions are met, and the load distribution result is obtained. The preset mechanical equilibrium conditions can be the conditions under which the internal forces and external loads reach a state of equilibrium during the load distribution process; the preset interaction coordination conditions refer to the geometric compatibility conditions that the displacement and deformation of the stamping die and the workpiece in the interaction area should meet. For example, the normal displacement on the contact surface does not penetrate, and the tangential displacement conforms to the friction law.

[0042] This application embodiment employs a finite element method (FEM) solver and a pre-defined mechanical analysis algorithm to iteratively calculate stamping load parameters within the interaction region. The FEM solver provides powerful numerical simulation capabilities, accurately simulating the complex contact and mechanical behavior between the stamping die and the workpiece. The pre-defined mechanical analysis algorithm ensures that the calculation process follows actual physical laws. Iterative calculations allow for gradual adjustment of load distribution. Therefore, in each iteration, the load distribution is corrected based on the current deformation and stress state, ensuring that the final load distribution not only satisfies mechanical equilibrium but also maintains geometric coordination at the die-workpiece contact interface. This avoids unreasonable stress concentration or penetration, enabling the load distribution result to closely approximate actual working conditions. This improves the accuracy and stability of stamping load parameter distribution within the interaction region, thereby enhancing the overall accuracy and reliability of the stamping die life prediction method.

[0043] In some embodiments, the life prediction of a stamping die for an automotive body panel is performed by first acquiring the current service status information of the die, including stamping load parameters and cumulative damage distribution information in the cutting edge region. When allocating the load, the interaction region between the die cutting edge region and the workpiece is divided into finite element meshes. Then, using a finite element solver and combining preset elastoplastic constitutive models, contact friction models, and other mechanical analysis algorithms, iterative calculations are performed in each stamping cycle. During the iteration process, the contact force, friction force, and deformation of the die and workpiece are continuously adjusted until the resultant force on all mesh nodes approaches zero (satisfying the mechanical equilibrium condition), and the contact surface between the die and the workpiece does not penetrate or separate (satisfying the interaction compatibility condition). For example, if in a certain iteration, it is found that the normal force at a certain contact point is too large, causing abnormal workpiece deformation, the solver will adjust the load allocation at that point and recalculate until equilibrium is reached. Finally, when the iteration converges and all preset conditions are met, the load allocation result is obtained.

[0044] In one embodiment of the numerical analysis-based method for predicting the life of stamping dies provided in this application, step S130 may include, but is not limited to, steps S510 to S520.

[0045] Step S510: Update the material properties of each mesh node according to the cumulative damage information of each mesh node; Step S520: Based on the updated material properties and load distribution results of each mesh node, Newton-Raphson iteration is performed through the finite element solver to output the stress tensor components, equivalent stress, and hydrostatic stress of each mesh node in the current stamping die cutting edge region, thereby obtaining the stress distribution information of the current stamping die cutting edge region.

[0046] For example, during the service life of a stamping die, the material in the cutting edge region will accumulate damage due to factors such as wear and fatigue. This accumulated damage will affect the material's mechanical properties, such as elastic modulus, yield strength, and hardness. Therefore, to accurately assess the stress state of the current stamping die's cutting edge region, the material properties of the mesh nodes can be dynamically updated based on the accumulated damage information corresponding to each mesh node. For example, as the accumulated damage increases, the material's strength and stiffness may decrease. After updating the material properties of each mesh node, a detailed mechanical analysis can be performed using a finite element method based on the updated material properties and the previously obtained load distribution results. Here, since the material behavior during the stamping process is often nonlinear, the Newton-Raphson iterative method can be used for solving the problem.

[0047] Through iterative calculations, the stress tensor components, equivalent stress, and hydrostatic stress of each mesh node within the current stamping die cutting edge region can be output. The stress tensor components provide a complete description of the internal stress state of the material; the equivalent stress is used to determine whether the material yields or fails; and the hydrostatic stress characterizes the average stress state within the material, particularly relevant to certain damage mechanisms. By combining the stress information, the stress distribution information of the current stamping die cutting edge region can be obtained.

[0048] For example, in this embodiment, the material properties are updated based on the cumulative damage information of each mesh node before stress analysis, ensuring that the material model used in subsequent mechanical analysis can accurately represent the current damage state of the stamping die cutting edge region. By introducing a dynamic update mechanism for material properties, the degradation of mechanical properties caused by damage can be captured more accurately, allowing the finite element solver to perform calculations based on a more realistic material constitutive relation during the Newton-Raphson iteration process. Thus, the output stress tensor components, equivalent stress, and hydrostatic stress can accurately represent the true stress state of the current stamping die cutting edge region, improving the calculation accuracy of stress distribution information in the stamping die cutting edge region.

[0049] In a numerical analysis-based method for predicting the life of stamping dies provided in one embodiment of this application, the current damage increment includes wear damage increment and fatigue damage increment, the cumulative damage information includes cumulative wear damage information and cumulative fatigue damage information, and the current cumulative damage information includes current cumulative wear damage information and current cumulative fatigue damage information.

[0050] For example, the current damage increment includes wear damage increment and fatigue damage increment. Wear damage increment refers to the amount of damage caused by friction or contact between the stamping die and the workpiece or other components during one stamping cycle, resulting in material loss or changes in surface morphology. This manifests as material wear in the die cutting edge area and increased surface roughness. Fatigue damage increment refers to the amount of damage caused by repeated stress on the stamping die during one stamping cycle, resulting in changes in the internal structure of the material or the initiation and propagation of microcracks. This manifests as fatigue cracks in the material and reduced fatigue life.

[0051] Cumulative damage information includes cumulative wear damage information and cumulative fatigue damage information. Cumulative wear damage information refers to the cumulative sum of all wear damage increments of the stamping die from the start of its service to the present moment, characterizing the degree of overall material loss and geometric change of the die due to wear. Cumulative fatigue damage information refers to the cumulative sum of all fatigue damage increments of the stamping die from the start of its service to the present moment, characterizing the degree of decline in the overall structural integrity of the die due to fatigue.

[0052] The current cumulative damage information includes the current cumulative wear damage information and the current cumulative fatigue damage information. The current cumulative wear damage information refers to the total wear damage state reached by the die cutting edge area after the current stamping cycle ends; the current cumulative fatigue damage information refers to the total fatigue damage state reached by the die cutting edge area after the current stamping cycle ends.

[0053] It is understood that by subdividing the damage increment and cumulative damage information into wear damage and fatigue damage, the embodiments of this application can more accurately characterize the complex damage mechanisms that stamping dies experience during actual service. Wear damage mainly affects the geometric accuracy and surface quality of the die, while fatigue damage mainly affects the structural integrity and load-bearing capacity of the die. By evaluating the two types of damage separately, the evaluation bias that may be caused by a single damage index can be avoided, achieving a refined evaluation of the damage state of the stamping die and improving the accuracy of damage assessment.

[0054] In one embodiment of the numerical analysis-based method for predicting the life of stamping dies provided in this application, the method may include, but is not limited to, steps S610 to S620.

[0055] Step S610: Obtain the surface physical structure information of the current stamping die cutting edge area, and obtain the surface physical thickness based on the cumulative wear damage information and surface physical structure information of the current stamping die cutting edge area; Step S620: When the surface physical thickness is less than the preset thickness threshold, reduce the current cumulative fatigue damage information and store the reduced current cumulative fatigue damage information in the mold model so as to be used as the cumulative fatigue damage information in the next calculation of the current cumulative fatigue damage information.

[0056] For example, the surface physical structure information of the current stamping die cutting edge area is obtained. This information can be physical characteristic data such as the actual surface morphology, roughness, and microcrack distribution of the cutting edge area. This data can be acquired using non-contact optical measurement equipment or contact measurement equipment, and is used to characterize the geometric changes on the die surface caused by wear. Based on the cumulative wear damage information and surface physical structure information of the current stamping die cutting edge area, the surface physical thickness is obtained. For example, by comparing the surface physical structure information with the original die geometry model and combining it with the cumulative wear damage information, the actual material loss can be quantified, thereby determining the current effective physical thickness. The surface physical thickness can be understood as the effective load-bearing thickness of the stamping die cutting edge area after considering wear damage and the actual surface structure. The preset thickness threshold is a critical thickness value pre-set based on the die material characteristics, design requirements, and actual service experience. When the surface physical thickness of the die cutting edge area is lower than this threshold, it indicates that the die has undergone significant wear, and its fatigue performance is affected. In this case, the current cumulative fatigue damage information will be reduced, and the assessment of fatigue damage will be corrected to more accurately characterize the actual fatigue damage of the mold under severe wear conditions, avoiding overestimation of fatigue damage due to surface material loss.

[0057] The reduced current cumulative fatigue damage information can be stored in the mold model and used as cumulative fatigue damage information in the next calculation of current cumulative fatigue damage information, ensuring that the evaluation can be based on a more realistic damage state in subsequent lifetime prediction iteration calculations.

[0058] Understandably, when the detected surface physical thickness is less than a preset thickness threshold, it indicates that the mold has entered a severe wear stage. At this point, the mold's geometry and stress distribution have changed. This means the wear process has removed some of the material accumulated by fatigue damage, or the geometric changes caused by wear have altered the stress concentration areas, extending the fatigue life of the remaining material to some extent or requiring reassessment. By reducing the current accumulated fatigue damage information, the fatigue damage assessment can be corrected, coupling the two main damage mechanisms of wear and fatigue. This allows the life prediction model to adapt to the actual damage state of the mold at different service stages, avoiding premature mold failure due to overestimation of fatigue damage, thereby improving the accuracy and reliability of the mold's remaining service life prediction.

[0059] In some embodiments, a high-precision 3D scanner can be used to acquire the surface physical structure information of the current stamping die cutting edge region. For example, the microscopic morphology data and actual geometric contour of the region can be obtained. Simultaneously, the cumulative wear damage information of the region can be extracted from the die model, and the surface physical thickness of the current stamping die cutting edge region can be calculated. If the calculated surface physical thickness is less than a preset thickness threshold, it is determined that the die has undergone severe wear. In this case, in order to accurately characterize the fatigue state of the die, the current cumulative fatigue damage information can be reduced. For example, the current cumulative fatigue damage value can be multiplied by a correction coefficient less than 1 based on the difference between the surface physical thickness and the threshold or a preset attenuation function, thereby obtaining the reduced current cumulative fatigue damage information.

[0060] like Figure 2 As shown, Figure 2 This is a flowchart of a method for predicting the life of stamping dies based on numerical analysis provided in another embodiment of this application. Regarding step S140 above, the method may include, but is not limited to, steps S710 to S720.

[0061] Step S710: Extract the cumulative damage information, node coordinates and shape functions of the mesh nodes before adjustment in the local re-division area, and establish a set of node equations based on the node coordinates and shape functions of the mesh nodes before adjustment in the local re-division area. Calculate the set of node equations using a preset transformation algorithm to obtain the node coordinates of the mesh nodes after adjustment in the local re-division area. Step S720: Based on the cumulative damage information of the unadjusted mesh nodes in the local re-division region, interpolation calculation is performed using shape functions with the node coordinates of the adjusted mesh nodes in the local re-division region as weights to obtain the cumulative damage information of the adjusted mesh nodes in the local re-division region.

[0062] Understandably, after performing mesh quality verification and local re-meshing on multiple adjusted mesh nodes, the correspondence between the original cumulative damage information and the new mesh nodes may change. Without corresponding adjustments, the accuracy of subsequent damage assessment and life prediction will be affected. Therefore, it is advisable to first extract the cumulative damage information, node coordinates, and shape functions of the original mesh nodes within the locally re-meshed area. Shape functions are used in finite element analysis to describe how physical quantities at any point within an element are interpolated from physical quantities at the nodes.

[0063] Subsequently, a set of node equations is established based on the node coordinates and shape functions of the original mesh nodes within the locally re-divided region. This set of node equations describes the geometric mapping relationship between the mesh nodes before and after the adjustment. Then, the node equations are calculated using a preset transformation algorithm to obtain the node coordinates of the adjusted mesh nodes within the locally re-divided region. The preset transformation algorithm can be a geometric transformation, interpolation, or projection algorithm, used to calculate the coordinates of newly generated mesh nodes within the locally re-divided region while meeting mesh quality requirements and boundary constraints. For example, a method based on finite element shape function mapping can be used to map the geometric information of the old mesh onto the new mesh, thereby determining the position of the new mesh nodes.

[0064] After determining the coordinates of the adjusted mesh nodes, it is necessary to accurately transfer the original cumulative damage information to these new nodes. Therefore, based on the cumulative damage information of the original mesh nodes within the locally re-divided region, interpolation calculations are performed using shape functions with the node coordinates of the adjusted mesh nodes within the locally re-divided region as weights. In other words, using the cumulative damage information of the original mesh nodes as known quantities, combined with shape functions, and using the coordinates of the adjusted mesh nodes as interpolation points, interpolation calculations are performed. The shape function acts as a weighting function in this process, proportionally allocating the damage information of the old nodes to the new nodes based on the topological relationship and distance between the new and old nodes, thus obtaining the cumulative damage information corresponding to the new mesh nodes. This ensures that the damage history of the die cutting edge region can be accurately inherited and updated after changes in the mesh structure.

[0065] Therefore, this embodiment of the application establishes a set of node equations and uses a preset transformation algorithm to calculate the coordinates of the adjusted mesh nodes, ensuring the geometric accuracy of the new mesh. Then, using shape functions and the coordinates of the adjusted mesh nodes as weights, interpolation calculations are performed, which can smoothly and accurately map the cumulative damage information before adjustment to the new mesh nodes. This ensures that after the mesh is re-divided in the cutting edge area of ​​the stamping die, the cumulative damage information can be accurately and effectively transferred from the mesh nodes before adjustment to the mesh nodes after adjustment, avoiding the distortion or loss of damage information caused by mesh changes, and improving the accuracy and reliability of subsequent damage assessment and remaining service life prediction.

[0066] like Figure 3 As shown, Figure 3 This is a flowchart of a method for predicting the life of stamping dies based on numerical analysis provided in another embodiment of this application. Regarding step S720 above, the method may include, but is not limited to, steps S810 to S830.

[0067] Step S810: Calculate the damage gradient vector based on the cumulative damage information and node coordinates of the mesh nodes before adjustment within the local re-division region; Step S820: When the magnitude of the damage gradient vector is not greater than the preset magnitude threshold, the cumulative damage information of the adjusted mesh nodes in the local re-division region is obtained by interpolation calculation using shape functions with the node coordinates of the adjusted mesh nodes in the local re-division region as weights. Step S830: When the magnitude of the damage gradient vector is greater than the preset magnitude threshold, the cumulative damage information of the unadjusted mesh nodes in the largest local repartition region is taken as the extreme control point. Based on the extreme control point, the topological distance coefficient between the node coordinates of the adjusted mesh nodes in the local repartition region and the extreme control point is calculated. Based on the topological distance coefficient, a correction shape function including a distance attenuation term is established. The cumulative damage information of the adjusted mesh nodes in the local repartition region is calculated through the correction shape function.

[0068] It is understandable that when interpolating the cumulative damage information of adjusted mesh nodes within a locally re-divided region, shape functions can be used with the node coordinates of the adjusted mesh nodes as weights. However, in some embodiments, the damage distribution in the cutting edge region of the stamping die is often uneven, especially in areas where wear or fatigue damage is concentrated, where the damage gradient may be very large, and local extrema exist. If only shape function interpolation is used, it may smooth the damage information in these high-gradient regions or extrema, thereby reducing the accuracy of damage assessment and consequently affecting the accuracy of predicting the remaining service life of the stamping die.

[0069] Based on this, the damage gradient vector can be calculated based on the cumulative damage information and node coordinates of the grid nodes before adjustment within the local re-division region. The damage gradient vector is a vector that describes the rate of change of the cumulative damage information in space within the local re-division region. It can be calculated by performing mathematical operations such as finite difference or least squares on the cumulative damage information and node coordinates of the grid nodes before adjustment, so as to characterize the local steepness of the damage distribution.

[0070] Correspondingly, the magnitude of the damage gradient vector can be understood as the intensity or magnitude of the damage change rate; the larger the magnitude, the more drastic the spatial change in damage. A preset magnitude threshold is used to distinguish whether the damage gradient is gentle or severe. When the magnitude of the damage gradient vector exceeds the preset magnitude threshold, the largest cumulative damage information in the unadjusted mesh nodes within the local re-division region is used as the extreme value control point. The extreme value control point represents the region with the most severe local damage, and it is given greater weight and influence during the interpolation process to accurately characterize the local peak value of the damage.

[0071] Subsequently, based on the extreme control points, the topological distance coefficient between the node coordinates of the adjusted grid nodes in the local re-division region and the extreme control points is calculated. The topological distance coefficient refers to the spatial distance relationship between the node coordinates of the adjusted grid nodes in the local re-division region and the extreme control points. The topological distance coefficient can be calculated based on Euclidean distance, geodesic distance or other topological metric methods to quantify the proximity between the interpolation point and the extreme control points.

[0072] Based on the topological distance coefficient, a modified shape function including a distance attenuation term is established. This modified shape function is used to calculate the cumulative damage information of adjusted mesh nodes within the locally repartitioned region. The distance attenuation term is a mathematical function whose value decreases as the topological distance coefficient increases. It introduces a distance-related weight into the modified shape function, ensuring that the cumulative damage information of mesh nodes closer to the extreme control point is more significantly influenced by the extreme control point. Therefore, the modified shape function including the distance attenuation term can more accurately describe the damage distribution in high-gradient regions, especially near extreme points. By adjusting the distance attenuation term, the interpolation result can better approximate the true damage peak, avoiding smoothing errors that may be caused by other interpolation methods.

[0073] Understandably, this application can adaptively select an appropriate interpolation strategy based on the actual damage distribution. In particular, when there is local damage concentration or a large damage gradient in the cutting edge area of ​​the stamping die, it can accurately adjust the cumulative damage information, avoid the damage peak smoothing error that may be caused by the interpolation method, improve the accuracy of the damage status assessment of the cutting edge area of ​​the stamping die, and ensure that the local features of the damage information can be accurately captured and transmitted, making the subsequent prediction of the remaining service life of the stamping die more reliable and accurate.

[0074] Secondly, this application provides a numerical analysis-based stamping die life prediction system, applied to a die model of a stamping die. The die model is used to store and manage die data, including a three-dimensional model of the stamping die, geometric parameters, and material property parameters. The stamping die life prediction system includes: The information acquisition module is used to acquire the current service status information of the stamping die. The current service status information includes stamping load parameters and cumulative damage distribution information of the cutting edge area of ​​the stamping die. The cutting edge area of ​​the stamping die includes multiple grid nodes, and the cumulative damage distribution information includes the cumulative damage information of each corresponding grid node. The geometry adjustment module is used to adjust multiple mesh nodes based on cumulative damage distribution information, and adjust the geometric representation parameters of the stamping die cutting edge region through the adjusted multiple mesh nodes to obtain the current stamping die cutting edge region. The interaction area between the stamping die and the workpiece is determined through the current stamping die cutting edge region. The stress analysis module is used to distribute the load in the interaction area based on the stamping load parameters to obtain the load distribution result. Based on the load distribution result, the stress distribution information of the current stamping die cutting edge area is obtained. The damage assessment module is used to determine the current damage increment of the cutting edge area of ​​the current stamping die based on the stress distribution information, adjust the cumulative damage information based on the differences of multiple mesh nodes before and after adjustment, and obtain the current cumulative damage information based on the adjusted cumulative damage information and the current damage increment. The life prediction module is used to predict the remaining service life of the stamping die based on the current cumulative damage information.

[0075] The above are merely embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for predicting the life of stamping dies based on numerical analysis, characterized in that, A die model is applied to the stamping die. This die model stores, manages, and analyzes die data, including the three-dimensional model of the stamping die, geometric parameters, and material property parameters. The numerical analysis-based method for predicting the life of the stamping die includes: Obtain the current service status information of the stamping die, which includes stamping load parameters and cumulative damage distribution information of the cutting edge area of ​​the stamping die. The cutting edge area of ​​the stamping die includes multiple grid nodes, and the cumulative damage distribution information includes the cumulative damage information corresponding to each grid node. Based on the cumulative damage distribution information, the multiple mesh nodes are adjusted, and the geometric representation parameters of the stamping die cutting edge region are adjusted through the adjusted multiple mesh nodes to obtain the current stamping die cutting edge region. The interaction region between the stamping die and the workpiece is determined through the current stamping die cutting edge region. Based on the stamping load parameters, load distribution is performed in the interaction region to obtain load distribution results. Based on the load distribution results, stress distribution information of the current stamping die cutting edge region is obtained. Based on the stress distribution information, the current damage increment of the current stamping die cutting edge area is determined. Based on the difference between multiple mesh nodes before and after adjustment, the cumulative damage information is adjusted. Based on the adjusted cumulative damage information and the current damage increment, the current cumulative damage information is obtained. Based on the current cumulative damage information, the remaining service life of the stamping die is predicted.

2. The method for predicting the life of stamping dies based on numerical analysis according to claim 1, characterized in that, The step of adjusting the multiple grid nodes based on the cumulative damage distribution information includes: Based on the topological relationships around each of the grid nodes, the weighted average inner normal vector of each of the grid nodes is obtained; The wear depth of each mesh node is determined based on the cumulative damage information of each mesh node, and the coordinates of each mesh node are adjusted along the weighted average inner normal vector of each mesh node based on the wear depth of each mesh node.

3. The method for predicting the life of stamping dies based on numerical analysis according to claim 1, characterized in that, After adjusting the multiple grid nodes based on the cumulative damage distribution information, the numerical analysis-based method for predicting the life of stamping dies further includes: Perform mesh quality verification on multiple adjusted mesh nodes to determine the degree of distortion of each mesh node; If the distortion of at least one mesh node exceeds a preset distortion threshold, a local re-division region is defined centered on the mesh node whose distortion exceeds the preset distortion threshold. The boundaries of the mesh nodes whose distortion does not exceed the distortion threshold and the boundaries of the current stamping die cutting edge region are used as constraints to re-divide the mesh nodes in the local re-division region to update the adjusted multiple mesh nodes.

4. The method for predicting the life of stamping dies based on numerical analysis according to claim 1, characterized in that, The process of distributing the load in the interaction region based on the stamping load parameters to obtain the load distribution result includes: Within the interaction region, the load distribution of the stamping load parameters is iteratively calculated using a finite element solver and a preset mechanical analysis algorithm until the preset mechanical equilibrium condition and preset interaction coordination condition are met, thus obtaining the load distribution result.

5. The method for predicting the life of stamping dies based on numerical analysis according to claim 1, characterized in that, The step of obtaining stress distribution information in the current stamping die cutting edge region based on the load distribution results includes: Update the material properties of each mesh node based on the cumulative damage information of each mesh node; Based on the updated material properties and load distribution results of each mesh node, the stress tensor components, equivalent stress, and hydrostatic stress of each mesh node in the current stamping die cutting edge region are output through the Newton-Raphson iteration of the finite element solver, thereby obtaining the stress distribution information of the current stamping die cutting edge region.

6. The method for predicting the life of stamping dies based on numerical analysis according to claim 1, characterized in that, The current damage increment includes wear damage increment and fatigue damage increment, the cumulative damage information includes cumulative wear damage information and cumulative fatigue damage information, and the current cumulative damage information includes current cumulative wear damage information and current cumulative fatigue damage information.

7. The method for predicting the life of stamping dies based on numerical analysis according to claim 6, characterized in that, The numerical analysis-based method for predicting the life of stamping dies also includes: Obtain the surface physical structure information of the current stamping die cutting edge area, and obtain the surface physical thickness based on the cumulative wear damage information and surface physical structure information of the current stamping die cutting edge area; If the physical thickness of the surface is less than a preset thickness threshold, the current cumulative fatigue damage information is reduced, and the reduced current cumulative fatigue damage information is stored in the mold model to be used as cumulative fatigue damage information in the next calculation of the current cumulative fatigue damage information.

8. The method for predicting the life of stamping dies based on numerical analysis according to claim 3, characterized in that, The step of adjusting the cumulative damage information based on the differences between multiple grid nodes before and after the adjustment includes: Extract the cumulative damage information, node coordinates, and shape functions of the unadjusted mesh nodes within the local re-division region. Establish a set of node equations based on the node coordinates and shape functions of the unadjusted mesh nodes within the local re-division region. Calculate the set of node equations using a preset transformation algorithm to obtain the node coordinates of the adjusted mesh nodes within the local re-division region. Based on the cumulative damage information of the unadjusted mesh nodes in the local re-division region, the cumulative damage information of the adjusted mesh nodes in the local re-division region is obtained by interpolation calculation using the shape function with the node coordinates of the adjusted mesh nodes in the local re-division region as weights.

9. The method for predicting the life of stamping dies based on numerical analysis according to claim 8, characterized in that, The step of obtaining the cumulative damage information of the adjusted mesh nodes in the locally re-divided region by interpolating using the shape function with the node coordinates of the adjusted mesh nodes in the locally re-divided region as weights, based on the cumulative damage information of the unadjusted mesh nodes in the locally re-divided region, includes: Based on the cumulative damage information and node coordinates of the mesh nodes before adjustment within the local re-division region, calculate the damage gradient vector; When the magnitude of the damage gradient vector is not greater than a preset magnitude threshold, the cumulative damage information of the adjusted mesh nodes in the local re-division region is obtained by interpolation calculation using the shape function with the node coordinates of the adjusted mesh nodes in the local re-division region as weights. When the magnitude of the damage gradient vector is greater than the preset magnitude threshold, the cumulative damage information of the unadjusted mesh nodes in the largest local repartition region is taken as the extreme control point. Based on the extreme control point, the topological distance coefficient between the node coordinates of the adjusted mesh nodes in the local repartition region and the extreme control point is calculated. Based on the topological distance coefficient, a modified shape function including a distance attenuation term is established. The cumulative damage information of the adjusted mesh nodes in the local repartition region is calculated through the modified shape function.

10. A stamping die life prediction system based on numerical analysis, characterized in that, A die model applied to the stamping die, the die model being used to store, manage, and analyze die data including the three-dimensional model of the stamping die, geometric parameters, and material property parameters; the numerical analysis-based stamping die life prediction system includes: The information acquisition module is used to acquire the current service status information of the stamping die. The current service status information includes stamping load parameters and cumulative damage distribution information of the cutting edge area of ​​the stamping die. The cutting edge area of ​​the stamping die includes multiple grid nodes, and the cumulative damage distribution information includes the cumulative damage information corresponding to each grid node. The geometry adjustment module is used to adjust the multiple mesh nodes based on the cumulative damage distribution information, and adjust the geometric representation parameters of the stamping die cutting edge region through the adjusted multiple mesh nodes to obtain the current stamping die cutting edge region, and determine the interaction region between the stamping die and the workpiece through the current stamping die cutting edge region; The stress analysis module is used to perform load distribution in the interaction region based on the stamping load parameters to obtain load distribution results, and to obtain stress distribution information of the current stamping die cutting edge region based on the load distribution results; The damage assessment module is used to determine the current damage increment of the cutting edge area of ​​the current stamping die based on the stress distribution information, adjust the cumulative damage information based on the difference of multiple mesh nodes before and after adjustment, and obtain the current cumulative damage information based on the adjusted cumulative damage information and the current damage increment. The life prediction module is used to predict the remaining service life of the stamping die based on the current cumulative damage information.

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