Shot peening forming deformation prediction method and system based on three-layer equivalent inherent strain

Abstract

The invention provides a shot peening forming deformation prediction method and system based on three-layer equivalent inherent strain, and the method comprises the steps that the three-layer equivalent inherent strain under preset technological parameters is calibrated based on a calibration sample of a preset size, and the preset technological parameters are technological parameters adopted when a target wallboard is machined; establishing a finite element model of the target wallboard, dividing the finite element model into three layers along the thickness direction of the finite element model, and dividing plane grids; loading the calibrated three-layer equivalent inherent strain to a shot blasting area of the finite element model; and activating the inherent strain field and carrying out elastic analysis to obtain a deformation prediction result. According to the embodiment of the invention, efficient, accurate and universal shot peening forming deformation prediction can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mechanical manufacturing, in particular to a shot forming deformation prediction method and system based on three-layer equivalent inherent strain. BACKGROUND

[0002] Shot forming induces local cold plastic deformation on the surface of metal materials through high-amplitude impact pressure. The cumulative loading of impact pressure causes progressive cumulative plastic deformation of the metal plate, and the cumulative effect of plastic deformation ultimately realizes the forming manufacturing of the whole target plate. Shot forming has broad application prospects in the fields of aviation, aerospace, high-speed transportation, etc. At present, mechanical shot forming based on random impact of rigid projectiles and laser shot forming using high-energy short pulse laser as an energy source have been applied in industrial manufacturing. However, the deformation process of shot forming is complex, and how to realize efficient and accurate deformation prediction is still a difficult problem in engineering application.

[0003] In the prior art, patent document CN202011283631.0 provides a numerical simulation method for prestressed shot forming of ribbed wall plate, including the following steps: first, establishing a correlation model between shot forming process parameters and shot forming simulation parameters; then: establishing a multi-projectile impact model and extracting the path node stress of the shot forming area along the thickness direction of the model; further, establishing a bending stress field model of the ribbed wall plate, converting the wall plate into a finite element shell element and performing partition processing, and then assigning the stress field to the shell element to realize deformation prediction. The present application realizes deformation simulation of the ribbed wall plate based on the shot forming stress field method, but still uses induced stress as the equivalent variable, which makes it difficult to ensure the accuracy of the deformation prediction result.

[0004] Therefore, realizing efficient and accurate deformation prediction is a key problem to be solved in the engineering application of shot forming. SUMMARY

[0005] The present application aims to provide a shot forming deformation prediction method and system based on three-layer equivalent inherent strain, which can realize efficient, accurate and universal shot forming deformation prediction.

[0006] To solve the above technical problems, the present application provides a shot forming deformation prediction method based on three-layer equivalent inherent strain, characterized in that it comprises:

[0007] Step S1: calibrate the three-layer equivalent inherent strain under the preset process parameters based on the calibration sample of the preset size, the preset process parameters being the process parameters used for processing the target wallboard; Step S2: establish a finite element model of the target wallboard, which is divided into three layers and planar grids along the thickness direction of the finite element model; Step S3: load the three-layer equivalent inherent strain obtained by calibration to the shot blasting area of the finite element model; Step S4: activate the inherent strain field and perform elastic analysis to obtain the deformation prediction result.

[0008] Optionally, the calibration sample at least meets the following conditions:

[0009] The thickness h of the calibration sample is the same as that of the target wallboard; the material of the calibration sample is the same as that of the target wallboard; the in-plane plate length of the calibration sample is the same as that of the target wallboard. Wherein, is the maximum principal component value corresponding to the preset process parameters.

[0010] Optionally, step S1 includes: performing full-coverage shot forming on the calibration sample according to the preset process parameters; measuring the minimum principal curvature k1 and the maximum principal curvature k2 of the calibration sample after shot forming; and calculating the value of the three-layer equivalent inherent strain according to the minimum principal curvature k1 and the maximum principal curvature k2.

[0011] Optionally, the three-layer equivalent inherent strain is calculated as follows:

[0012]

[0013] Wherein, the x direction is defined as the minimum principal curvature direction, the y direction is defined as the maximum principal curvature direction, k2>k1, is the three-layer equivalent inherent strain in the x direction, are the equivalent inherent strain values of the first layer, the second layer and the third layer in the x direction respectively, is the three-layer equivalent inherent strain in the y direction, are the equivalent inherent strain values of the first layer, the second layer and the third layer in the y direction respectively.

[0014] Optionally, step S3 includes: implanting a thermal expansion coefficient in each layer unit along the thickness direction of the shot blasting area to load the three-layer equivalent inherent strain obtained by calibration to the shot blasting area of the finite element model, wherein the thermal expansion coefficient implanted in each layer unit corresponds to the equivalent inherent strain value of the layer.

[0015] The thermal expansion coefficient is represented as:

[0016]

[0017] Among them, α1, α2, and α3 represent the thermal expansion coefficient values ​​of the first, second, and third layers, respectively; Represent the equivalent inherent strain values ​​corresponding to the first, second and third layers respectively; are the equivalent inherent strain values ​​of the first, second and third layers in the x-direction, are the equivalent inherent strain values ​​of the first, second and third layers in the y direction, respectively.

[0018] Optionally, step S4 includes: activating the inherent strain field of implanting the thermal expansion coefficient into the shot peening area by loading a global temperature field ΔT, where ΔT=1.

[0019] Optionally, the elasticity analysis in step S4 includes:

[0020] like No geometric nonlinear analysis is performed; if A geometric nonlinear analysis is performed; where k2 is the maximum principal curvature value of the calibration specimen after shot peening; l is the in-plane plate length of the calibration specimen; and h is the thickness of the calibration specimen.

[0021] Optionally, before activating the inherent strain field, the method further includes: setting boundary conditions to eliminate rigid body displacement during the numerical simulation process of the plate.

[0022] On the other hand, an embodiment of the present application provides a shot peening deformation prediction system based on three-layer equivalent inherent strain, which is applied to the above-mentioned shot peening deformation prediction method, including: a calibration module: used to calibrate the three-layer equivalent inherent strain under preset process parameters based on a calibration specimen of preset size, and the preset process parameters are the process parameters used when processing the target wall panel; a model building module: used to establish a finite element model of the target wall panel, dividing it into three layers along the thickness direction of the finite element model and dividing it into a plane grid; a data loading module: used to load the calibrated three-layer equivalent inherent strain into the shot peening area of ​​the finite element model; an analysis module: used to activate the inherent strain field and perform elastic analysis to obtain deformation prediction results.

[0023] Optionally, the calibration module includes:

[0024] Shot peening equipment: used to perform full-coverage shot peening on the calibration specimen according to the preset process parameters; measurement module: used to measure the minimum principal curvature k1 and the maximum principal curvature k2 of the calibration specimen after forming; calculation module: used to calculate the numerical value of the equivalent inherent strain of the three layers based on the minimum principal curvature k1 and the maximum principal curvature k2.

[0025] Another aspect of the embodiments of the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the steps of the shot forming deformation prediction method based on three-layer equivalent inherent strain.

[0026] Compared with the prior art, the embodiments of the present application have the following advantages.

[0027] 1. The embodiments of the present application propose to predict the deformation of shot forming based on three-layer equivalent inherent strain. Compared with the previous method of discretizing and layering the actual inherent strain, the modeling process is simpler and more direct, and the modeling efficiency is effectively improved.

[0028] 2. In the embodiments of the present application, the calibration of three-layer equivalent inherent strain can be quickly completed based on a small-size calibration sample, and then directly applied to the deformation prediction of the target wallboard. The calibration is simpler and more efficient than the calibration of complete inherent strain distribution, and the calibration result is more accurate.

[0029] 3. In the embodiments of the present application, the criterion for linear and nonlinear deformation is defined. When the deformation is in the linear range, the geometric nonlinearity does not need to be considered, which can improve the calculation efficiency. When the deformation is in the nonlinear range, the geometric nonlinearity must be considered, which can improve the accuracy of the calculation result.

[0030] 4. The embodiments of the present application are not only suitable for laser shot forming, but also suitable for mechanical shot forming, ultrasonic shot forming and other processes, and have high universality. BRIEF DESCRIPTION OF DRAWINGS

[0031] One or more embodiments are illustrated by way of example in the drawings, which are not intended to be limiting of the embodiments, and which will be described in the following. Elements having the same reference numbers in figures mean the same element. The drawings are not necessarily to scale, the emphasis instead being placed upon illustrating the principles of the embodiments.

[0032] Figure 1 is a flowchart of a shot forming deformation prediction method according to an embodiment of the present application;

[0033] Figure 2 is a schematic diagram of a calibration sample according to an embodiment of the present application;

[0034] Figure 3 is a schematic diagram of a three-layer equivalent inherent strain modeling method according to an embodiment of the present application;

[0035] Figure 4 is a schematic diagram of a shot forming modeling based on three-layer equivalent inherent strain according to an embodiment of the present application;

[0036] Figure 5 is a schematic diagram of in-plane mesh division of a finite element model according to an embodiment of the present application;

[0037] Figure 6a is a schematic diagram of a full coverage shot area according to an embodiment of the present application;

[0038] Figure 6b is a schematic diagram of a "+" shaped shot area according to an embodiment of the present application;

[0039] Figure 6c is a schematic diagram of an "I" shaped shot area according to an embodiment of the present application;

[0040] Figure 7a is a schematic diagram of the ablation area distribution of the absorbing layer attached to the surface of the plate processed according to an embodiment of the present application under a full coverage shot area;

[0041] Figure 7b is a schematic diagram of the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface under a full coverage shot area according to an embodiment of the present application;

[0042] Figure 8a is a schematic diagram of the ablation area distribution of the absorbing layer attached to the surface of the plate processed according to an embodiment of the present application for a "+" shaped shot area;

[0043] Figure 8b is a schematic diagram of the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface under a "+" shaped shot area according to an embodiment of the present application;

[0044] Figure 9a is a schematic diagram of the ablation area distribution of the absorbing layer attached to the surface of the plate processed according to an embodiment of the present application for an "I" shaped shot area;

[0045] Figure 9b is a schematic diagram of the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface under an "I" shaped shot area according to an embodiment of the present application;

[0046] Figure 10 is a schematic diagram of the structure of a shot forming deformation prediction system according to an embodiment of the present application;

[0047] Figure 11 is a schematic diagram of the structure of a shot forming deformation prediction system according to another embodiment of the present application. DETAILED DESCRIPTION

[0048] The following detailed description is presented in terms of specific embodiments illustrating the applications. These descriptions and examples are provided as disclosure of the applications and are not intended to limit the scope of the applications. Furthermore, various omissions, substitutions and changes in the form of the process described herein can be made without departing from the spirit of the application. It is to be understood that the various embodiments described herein are only examples of the principles of the application and are not intended to limit the scope of the application to such specific embodiments. It is therefore evident that there are many alternatives that fall within the scope of the present application. Any feature described in relation to one embodiment can be incorporated into any other embodiment unless clearly contradicted by context.

[0049] It is to be understood that the foregoing description is merely illustrative of the various aspects of the embodiments described herein. Consequently, numerous modifications and adaptations thereof will be apparent to those skilled in the art without departing from the spirit and scope of the application. Specific details need not be included in order to appreciate the application. Other implementations can have different specific details or can lack some details or have other specific details not shown in the figures. Those of ordinary skill in the art, having the benefit of the teachings of the present application as set forth above, will readily recognize that the application is not limited to the aspects and features set forth herein and that modifications and adaptations are possible.

[0050] It is also to be understood that the above-referenced methods, devices and systems are merely meant to be illustrative of the broader aspects of the present application. Certain embodiments of the application can be used in a variety of contexts, and are not limited to the specific examples described herein. Furthermore, it is intended that the application cover any and all modifications, variations, combinations or equivalents that fall within the scope of the present application. It should be apparent that aspects of the application and components of aspects of the application can be interchanged between methods, devices and systems. It should also be apparent that features described herein can be combined in any suitable manner without departing from the scope of the application.

[0051] In addition, in the following description, numerous specific details are provided for a thorough understanding of the examples. One skilled in the relevant art will recognize, however, that the application can be practiced without one or more of these specific details, or with other methods, components, materials, and so forth.

[0052] Since shot peening involves a wealth of adjustable process parameters and offers good process flexibility, intermediate variables are often used to represent the combined effects of multiple process parameters in order to reduce the complexity of process deformation prediction. Compared to intermediate variables such as equivalent stress and equivalent temperature load, inherent strain has significant advantages such as geometric insensitivity and high computational efficiency. However, the inherent strain inversion process is complex, and its accuracy is difficult to guarantee. In addition, deformation prediction modeling based on inherent strain requires setting the inherent strain values ​​of each layer layer by layer in the numerical model based on the actual distribution of the inherent strain in the depth direction, which is a relatively cumbersome process. Therefore, establishing a more efficient shot peening deformation prediction method is of great significance for promoting the engineering application of shot peening.

[0053] Based on this, the embodiment of the present application provides a shot peening deformation prediction method based on three-layer equivalent inherent strain, such as Figure 1 As shown, the following steps are included:

[0054] In step 101, based on a calibration sample of preset size, the three-layer equivalent inherent strain under preset process parameters is calibrated. The preset process parameters are the process parameters used when processing the target wallboard. In the embodiment of the present application, the calibration sample of preset size can be a small-sized calibration sample, for example, a sample with a size of 50×50×3 cm. 3 Preferably, the calibration sample needs to meet the following conditions: the thickness h of the calibration sample and the target wall panel is the same (for example, both are 3 cm); the material of the calibration sample and the target wall panel is the same (for example, both are made of 2024-T351 aluminum alloy); the in-plane plate length of the calibration sample is in It is the maximum principal component value of the inherent moment corresponding to the preset process parameters. It should be noted that in the embodiment of the present application, the thickness h of the calibration sample and the target wall panel may also be different. For example, the calibration sample after 3 cm can also be applicable to the shot peening deformation prediction of the target wall panel with a thickness of 4 cm, 5 cm, etc. The preset process parameters in the embodiment of the present application can be: laser energy (such as 11J), spot size (such as 3mm), spot overlap rate (20% for example), number of laser impacts (such as 1 time), laser scanning path (such as using a zigzag shape), etc. By calibrating these parameters, the inherent strain generated on the small sample can be directly transferred to the prediction model of the target wall panel to avoid repeated experiments on the target part. The same process parameters must be used for small sample calibration and target wall panel processing to ensure the direct applicability of the inherent strain calibration results.

[0055] In an optional embodiment, the three-layer equivalent intrinsic strain can be calibrated by the following method. First, the calibration sample is fully covered by shot forming according to the preset process parameters; then the minimum principal curvature k1 and the maximum principal curvature k2 of the formed calibration sample are measured; finally, the value of the three-layer equivalent intrinsic strain is calculated according to the minimum principal curvature k1 and the maximum principal curvature k2. When performing calibration experiments, the experiment can be repeated three times, for example, three calibration samples can be selected, and the calibration sample is fully covered by shot forming as shown in Figure 2 ,

[0056]

[0057] wherein the x direction is defined as the minimum principal curvature direction, the y direction is defined as the maximum principal curvature direction, is the three-layer equivalent intrinsic strain in the x direction, are the equivalent intrinsic strain values of the first layer, the second layer and the third layer in the x direction respectively, is the three-layer equivalent intrinsic strain in the y direction, are the equivalent intrinsic strain values of the first layer, the second layer and the third layer in the y direction respectively, and is the equivalent strain coefficient, which can be determined according to the shot experiment and bending mechanics.

[0058] Assuming k1 = 0.001236 mm -1 , k2 = 0.001569 mm -1 , the three-layer equivalent intrinsic strain can be calculated according to formula 1 as follows:

[0059]

[0060] In step 102, a finite element model of the target wallboard is established, which is divided into three layers along the thickness direction and is divided into a planar grid. In this embodiment, a plate with a geometric size of 300x300x3mm 3 is selected as the wallboard blank, which is the blank before the target wallboard is shot. In this embodiment, the finite element model can be established based on the ABAQUS finite element software according to the geometric size of the wallboard blank, and the material parameters of the model are consistent with those of the calibration sample (for example, both are 2024-T351 aluminum alloy). The model is divided into three unit layers along the thickness direction, as shown in Figure 3 , Figure 4 . Then the finite element model can be discretized into a planar grid with a node number of 180x180 by using S4R quadrilateral elements to capture deformation details, as shown inFigure 5 The three-layer finite element model established by the target wallboard in the embodiments of the present application can balance the accuracy and efficiency, and can avoid complex calculation process. Compared with the traditional method of discretizing the entire thickness direction (tens of layers), the three-layer model of the embodiments of the present application can reduce 90% of the calculation amount. It should be noted that in the embodiments of the present application, modeling can be performed according to wallboard blanks of different geometric sizes, and different material parameters can be defined in the modeling software to adapt to the deformation prediction of target wallboards of different materials and different specifications.

[0061] In step 103, the three-layer equivalent inherent strain obtained by calibration is loaded to the shot blasting area of the finite element model. Specifically, the shot blasting area of the finite element model in this step corresponds to the shot blasting area of the target wallboard, and the shot blasting area can be designed in three distribution forms, as shown in Figure 6a 、 6b , 6c, wherein Figure 6a as shown in the full-coverage shot blasting area, Figure 6b as shown in the "+" shot blasting area, Figure 6c as shown in the "I" shot blasting area. Alternatively, the thermal expansion coefficients are implanted along the thickness direction of the three-layer unit to load the three-layer equivalent inherent strain obtained by calibration to the shot blasting area of the finite element model, wherein the thermal expansion coefficient implanted in each layer unit corresponds to the equivalent inherent strain value of the layer;

[0062] The thermal expansion coefficient is represented as:

[0063]

[0064] wherein α1, α2, α3 represent the thermal expansion coefficient values implanted in the first layer, the second layer and the third layer, respectively, represent the equivalent inherent strain values corresponding to the first layer, the second layer and the third layer, respectively. are the equivalent inherent strain values of the first layer, the second layer and the third layer in the x direction, respectively, are the equivalent inherent strain values of the first layer, the second layer and the third layer in the y direction, respectively.

[0065] Suppose that the first layer equivalent inherent strain obtained by step 1 is then

[0066] α1 = [0.001390, 0.001765] (calibrated first layer inherent strain), α2 = [0, 0] (calibrated second layer inherent strain), and α3 = [-0.001390, -0.001765] (calibrated third layer inherent strain).

[0067] In step 104, the inherent strain field is activated and elastic analysis is performed to obtain the deformation prediction result. In the embodiment of the present application, the inherent strain field with the thermal expansion coefficient implanted in the shot peening area can be activated by loading the global temperature field ΔT, where ΔT = 1.

[0068] In a preferred embodiment, before reactivating the inherent strain field, the boundary conditions can be set to eliminate the rigid body displacement in the numerical simulation process of the plate.

[0069] More preferably, in the elastic analysis of the present step, the judgment of geometric nonlinear analysis can be performed, such as:

[0070] If , geometric nonlinear analysis is not performed;

[0071] If , geometric nonlinear analysis is performed;

[0072] where k2 is the maximum principal curvature value of the calibration specimen after shot peening forming; l is the in-plane plate length of the calibration specimen; and h is the thickness of the calibration specimen. In the present embodiment, by defining the criterion for linear and nonlinear deformation, the analysis method can be dynamically selected according to the degree of shot peening deformation. When the shot peening bending deformation is small, the deformation is in the linear range, and geometric nonlinear analysis is not required, which can improve the calculation efficiency. When the shot peening bending deformation is large, the deformation is in the nonlinear range, and geometric nonlinear analysis must be considered to ensure the accuracy of the calculation result. The deformation prediction result of the present embodiment of the present application can include displacement field, curvature distribution, geometric surface shape, etc. By comparing the prediction results under different parameters, the optimal shot peening energy, coverage rate, etc. can be screened, the process parameters can be optimized, and the product design verification, etc. can be performed in advance.

[0073] In the present embodiment of the present application, based on a small specimen (such as a 50×50×3mm 2 ), a plurality of groups of parameters can be calibrated quickly, and the optimal process can be screened. After calibrating the inherent strain corresponding to these parameters by using a small specimen, the deformation prediction of the target wall plate (such as a 300×300×3mm3) can be directly applied. The low-cost experiment of a small specimen is used to replace the repeated trial-and-error of a large-size part, and the process design efficiency is improved.

[0074] To verify the accuracy of the shot peening forming deformation prediction of the present embodiment, a laser shot peening forming experiment can be performed. The plate with a size of 300×300×3mm 3 is subjected to laser shot peening forming by using the preset process parameters calibrated in step 1. The material is also 2024-T351 aluminum alloy, and the shot peening area is also the full coverage area, the "+ type" area, and the "I type" area shown in 6c, 6d, and 6e. The ablation area of the shot peening forming plate surface covered by the absorbing layer is shown in FIG. 7. Figure 6a 6b The results show that the deformation prediction result of the present embodiment is accurate, and the process parameters calibrated by using a small specimen can be directly applied to the target wall plate.​Figure 7a As shown in FIG. 9b, the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface is as shown in FIG. 9c, and the maximum surface shape error is 5.46 mm; the ablation area of the absorption layer corresponding to the “+” shot peening area is as shown in FIG. 9d. Figure 7b As shown in FIG. 9b, the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface is as shown in FIG. 9c, and the maximum surface shape error is 5.46 mm; the ablation area of the absorption layer corresponding to the “+” shot peening area is as shown in FIG. 9d. Figure 8a As shown in FIG. 9b, the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface is as shown in FIG. 9c, and the maximum surface shape error is 5.46 mm; the ablation area of the absorption layer corresponding to the “+” shot peening area is as shown in FIG. 9d. Figure 8b As shown in FIG. 9b, the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface is as shown in FIG. 9c, and the maximum surface shape error is 5.46 mm; the ablation area of the absorption layer corresponding to the “+” shot peening area is as shown in FIG. 9d. Figure 9a As shown in FIG. 9b, the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface is as shown in FIG. 9c, and the maximum surface shape error is 5.46 mm; the ablation area of the absorption layer corresponding to the “+” shot peening area is as shown in FIG. 9d. Figure 9b As shown in FIG. 9b, the geometric surface shape comparison between the experimentally formed surface and the numerically predicted surface is as shown in FIG. 9c, and the maximum surface shape error is 5.46 mm; the ablation area of the absorption layer corresponding to the “+” shot peening area is as shown in FIG. 9d. Figure 7b 、 8b As shown in FIG. 9b, the experimentally formed surface in 9b is an actual shot forming surface obtained through a laser shot forming experiment, and the numerically predicted surface is a shot forming surface predicted according to the shot forming deformation prediction method provided in the embodiments of the present application. As can be seen from Figure 7b 、 8b As shown in FIG. 9b, the experimentally formed surface in 9b is an actual shot forming surface obtained through a laser shot forming experiment, and the numerically predicted surface is a shot forming surface predicted according to the shot forming deformation prediction method provided in the embodiments of the present application. As can be seen from

[0075] According to the embodiments of the present application, a small-sized calibration sample is subjected to full-coverage shot forming according to preset process parameters, and then three-layer equivalent inherent strain calibration is performed. The calibration method is simpler and more efficient, and the calibration result is more accurate. The shot forming deformation prediction is performed based on three-layer equivalent inherent strain, and compared with the previous way of discretizing and layering the actual inherent strain for import, the modeling process is simpler and more direct, and the modeling efficiency is effectively improved. In addition, the embodiments of the present application are not only suitable for laser shot peening, but also suitable for mechanical shot peening, ultrasonic shot peening and other processes, and have high universality.

[0076] Based on the same inventive concept, the present application also provides a shot forming deformation prediction system based on three-layer equivalent inherent strain. It should be noted that the system exemplified below is an example of the system corresponding to the above-mentioned one method embodiment, and in other system embodiments, the functions of the unit modules and the number of modules can be set according to the above-mentioned method embodiments.

[0077] As shown in FIG. 9b, the experimentally formed surface in 9b is an actual shot forming surface obtained through a laser shot forming experiment, and the numerically predicted surface is a shot forming surface predicted according to the shot forming deformation prediction method provided in the embodiments of the present application. As can be seen from Figure 10 The shot forming deformation prediction system comprises:

[0078] The calibration module 1 calibrates the three-layer equivalent inherent strain under the preset process parameters based on the calibration sample of the preset size, and the preset process parameters are the process parameters used for processing the target wall plate.

[0079] The model establishing module 2 establishes a finite element model of the target wallboard, divides the finite element model into three layers along the thickness direction of the finite element model, and divides a planar grid.

[0080] The data loading module 3 loads the three-layer equivalent inherent strain obtained through calibration into the shot blasting area of the finite element model.

[0081] The analysis module 4 activates the inherent strain field and performs elastic analysis to obtain a deformation prediction result.

[0082] Compared with the prior art, the calibration module 1 performs full-coverage shot blasting forming on a small-size calibration sample according to preset process parameters, and then performs calibration of three-layer equivalent inherent strain. The calibration method is more simple and efficient, and the calibration result is more accurate. The analysis module 4 performs deformation prediction of shot blasting forming based on three-layer equivalent inherent strain. Compared with the previous method of discretizing and layering the actual inherent strain for import, the modeling process is more simple and direct, and the modeling efficiency is effectively improved.

[0083] In an optional embodiment, as shown in Figure 11 The calibration module 1 includes:

[0084] The shot blasting device 11 performs full-coverage shot blasting forming on the calibration sample according to the preset process parameters.

[0085] The measurement module 12 measures the minimum principal curvature k1 and the maximum principal curvature k2 of the calibration sample after forming.

[0086] The calculation module 13 calculates the numerical value of the three-layer equivalent inherent strain according to the minimum principal curvature k1 and the maximum principal curvature k2.

[0087] The embodiment provides an implementation manner of a calibration module. Full-coverage shot blasting forming is performed on a small-size calibration sample according to preset process parameters, and then the numerical value of the three-layer equivalent inherent strain is calculated according to the measured minimum principal curvature k1 and maximum principal curvature k2 of the calibration sample after forming. The calibration method is more simple and efficient, and the calibration result is more accurate.

[0088] The embodiment of the application further provides a computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the steps of the shot blasting forming deformation prediction method according to any one of the embodiments.

[0089] It should be noted that the computer storage medium can include, but is not limited to, a portable disc, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device, or any suitable combination of the above. In a possible implementation, the present application can also provide a program product in the form of a program code for implementing data processing, which is used to make the terminal device execute a plurality of steps in the method according to any one of the above embodiments when the program product is run on the terminal device.

[0090] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above-described embodiments are not described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0091] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent application scope. It should be noted that for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

[0092] Those skilled in the art can understand that the above-described embodiments are specific embodiments for implementing the present application, and in actual applications, various changes can be made in form and details without departing from the spirit and scope of the present application.

Claims

1. A shot peening deformation prediction method based on three-layer equivalent inherent strain, characterized in that: include: Step S1: Calibrate the three-layer equivalent inherent strain under preset process parameters based on a calibration sample of preset size, where the preset process parameters are the process parameters used when processing the target wallboard; Step S2: establishing a finite element model of the target wall panel, dividing the finite element model into three layers along the thickness direction and dividing the model into plane grids; Step S3: loading the calibrated three-layer equivalent inherent strain into the shot peening area of ​​the finite element model; Step S4: Activate the inherent strain field and perform elastic analysis to obtain deformation prediction results.

2. The method according to claim 1, characterized in that The calibration sample in step S1 at least meets the following conditions: The thickness h of the calibration specimen and the target wall panel is the same; The calibration specimen and the target siding are made of the same material; In-plane plate length of calibration specimen in It is the maximum principal component value of the inherent moment corresponding to the preset process parameters.

3. The shot peening deformation prediction method according to claim 1, characterized in that: Step S1 includes: According to the preset process parameters, the calibration sample is subjected to full coverage shot peening; Measuring the minimum principal curvature k1 and the maximum principal curvature k2 of the calibration sample after shot peening; The values ​​of the equivalent inherent strains of the three layers are calculated based on the minimum principal curvature k1 and the maximum principal curvature k2.

4. The shot peening deformation prediction method according to claim 3, characterized in that: The calculation method of the three-layer equivalent inherent strain is as follows: Among them, the x direction is defined as the direction of minimum principal curvature, the y direction is defined as the direction of maximum principal curvature, k2>k1, is the three-layer equivalent inherent strain in the x direction, are the equivalent inherent strain values ​​of the first, second and third layers in the x-direction, is the three-layer equivalent inherent strain in the y direction, are the equivalent inherent strain values ​​of the first, second and third layers in the y direction, respectively.

5. The shot peening deformation prediction method according to claim 1, wherein: The step S3 comprises: Implanting thermal expansion coefficients in three layers of units along the thickness direction of the shot peening area respectively, so as to load the calibrated three-layer equivalent inherent strain into the shot peening area of ​​the finite element model, wherein the thermal expansion coefficient implanted in each layer of units corresponds to the equivalent inherent strain value of the layer; The thermal expansion coefficient is expressed as: Among them, α1, α2, and α3 represent the thermal expansion coefficient values ​​of the first, second, and third layers, respectively; Represent the equivalent inherent strain values ​​corresponding to the first, second and third layers respectively; are the equivalent inherent strain values ​​of the first, second and third layers in the x-direction, respectively; are the equivalent inherent strain values ​​of the first, second and third layers in the y direction, respectively.

6. The shot peening deformation prediction method according to claim 5, characterized in that: The step S4 comprises: The inherent strain field that embeds the thermal expansion coefficient into the shot peening area is activated by loading the global temperature field ΔT, where ΔT=1.

7. The shot peening deformation prediction method according to claim 1, characterized in that: The elasticity analysis in step S4 includes: like No geometric nonlinear analysis is performed; like Then perform geometric nonlinear analysis; Wherein, k2 is the maximum principal curvature value of the calibration specimen after shot peening; l is the in-plane plate length of the calibration specimen; and h is the thickness of the calibration specimen.

8. The shot peening deformation prediction method according to claim 1, characterized in that: Before activating the inherent strain field, also include: Set boundary conditions to eliminate rigid body displacement during the numerical simulation of the plate.

9. A shot peening deformation prediction system based on three-layer equivalent inherent strain, applied to the shot peening deformation prediction method according to any one of claims 1 to 8, characterized in that: include: Calibration module: used to calibrate the three-layer equivalent inherent strain under preset process parameters based on a calibration specimen of preset size, where the preset process parameters are the process parameters used when processing the target wall panel; Model building module: used for building a finite element model of the target wall panel, dividing the finite element model into three layers along the thickness direction and dividing the plane grid; Data loading module: used for loading the calibrated three-layer equivalent inherent strain into the shot peening area of ​​the finite element model; Analysis module: used to activate the inherent strain field and perform elastic analysis to obtain deformation prediction results.

10. The shot peening deformation prediction system according to claim 9, characterized in that: The calibration module includes: Shot peening equipment: used for performing full coverage shot peening on the calibration sample according to the preset process parameters; Measuring module: used to measure the minimum principal curvature k1 and the maximum principal curvature k2 of the calibration sample after forming; Calculation module: used for calculating the values ​​of the equivalent inherent strains of the three layers according to the minimum principal curvature k1 and the maximum principal curvature k2.

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