A method and device for predicting corrosion of a metal lap joint component

Abstract

The present invention discloses a method and device for predicting corrosion of metal lap joints. The method includes: collecting the structural parameters and material parameters of the metal lap joints; establishing a geometric model corresponding to the metal lap joints according to the structural parameters; setting the material, physical field, mesh and solver of the geometric model, and calculating the current density distribution; calculating the corrosion rate of the metal lap joints according to the current density distribution, and generating a corrosion rate distribution map to achieve prediction. By adopting the embodiment of the present invention, quantification of the corrosion process can be realized. By calculating the corrosion rate and generating a corrosion rate distribution map, prediction of the corrosion process is completed through modeling and simulation calculations based on the structural parameters and material parameters, reducing the operation and maintenance workload and improving the prediction efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of metal corrosion protection, and in particular, to a method and device for predicting the corrosion of metal lap joints. Background Art

[0002] The most widely used conductive materials in the power grid are copper and aluminum. In practical applications, the connection problem between copper conductors and aluminum conductors is inevitable. Since copper and aluminum are two metals with a large difference in electrode potential, when the contact surface of the two metals acts with moisture, carbon dioxide and other impurities in the air, it is extremely easy to form an electrolyte solution, thus forming a battery with aluminum as the negative electrode and copper as the positive electrode. An electrochemical reaction occurs between the two, causing aluminum to corrode, thereby reducing the safety of the copper-aluminum connection and affecting the safe operation of the power grid. In the prior art, to monitor or predict the corrosion of copper-aluminum lap joints, the method of manual inspection plus image recognition is usually adopted. Among them, the fractal dimension, total rust area, and average rust area of the binary images of metal corrosion images at multiple time points are calculated, the average rust area-time equation at multiple time points is fitted, and then the metal corrosion degree at a certain time point is comprehensively evaluated. However, the prior art has low prediction efficiency for the corrosion of metal lap joints, is difficult to quantify and evaluate, and the image sampling workload at multiple time points is large and the time span is long, which further reduces the prediction efficiency. Summary of the Invention

[0003] The present invention provides a method and device for predicting the corrosion of metal lap joints to solve the technical problems of low prediction efficiency and difficulty in quantification of the corrosion degree of metal lap joints in the prior art.

[0004] To solve the above technical problems, an embodiment of the present invention provides a method for predicting the corrosion of metal lap joints, including:

[0005] Collecting the structural parameters and material parameters of the metal lap joint;

[0006] According to the structural parameters and material parameters, establishing a geometric model, setting the material and physical fields of the geometric model, and calculating the current density distribution;

[0007] According to the current density distribution, calculating the corrosion rate of the metal lap joint and generating a corrosion rate distribution map for prediction.

[0008] After establishing a geometric model based on structural parameters and completing material testing of the bonding model using material parameters, the present invention sets up the physical field, mesh, and solver for simulation to obtain the current density distribution, thereby quantifying the corrosion process. In addition, based on the current density distribution, the corrosion rate is calculated and a corrosion rate distribution map is generated, realizing the prediction of the corrosion process through modeling and simulation calculations using structural parameters and material parameters, reducing the operation and maintenance workload, and improving the prediction efficiency.

[0009] Further, the collection of the structural parameters and material parameters of the metal lap joint component is specifically as follows:

[0010] According to on-site measurement of the metal lap joint component or the design drawing of the metal lap joint component, the structural parameters of the metal lap joint component are obtained; according to the product parameters of the metal lap joint component, the material parameters of the metal lap joint component are obtained.

[0011] The structural parameters of the present invention are from the metal lap joint component or the design drawing of the metal lap joint component, while the material parameters are mainly from the product parameters of the metal lap joint component. These two parameters are used for subsequent geometric model modeling and material setting, and no additional parameter collection and measurement are required to complete the calculation of current distribution and corrosion rate, improving the prediction efficiency.

[0012] Further, according to the structural parameters and material parameters, a geometric model is established, and the material and physical field of the geometric model are set, and the current density distribution is calculated, specifically as follows:

[0013] According to the structural parameters, a geometric model corresponding to the metal lap joint component is established;

[0014] According to the material parameters, the materials of each part of the geometric model are set;

[0015] The physical field of the secondary current distribution of the geometric model is set; the physical field of the current distribution - shell of the geometric model is set;

[0016] The tetrahedral mesh is selected to mesh the geometric model;

[0017] The solver is set, and according to the solver, the meshed geometric model is calculated to obtain the current density distribution.

[0018] The present invention sets the materials of each part of the geometric model according to material parameters, and by setting the physical field of the secondary current distribution, after setting the solver to a steady-state solver, it can calculate the surface current distribution of the metal lap joint component and quantify the intermediate process of corrosion rate calculation; adopts the current distribution-shell physical field to simulate the ion flow along the surface, avoiding grid meshing of the electrolyte liquid layer on the three-dimensional surface and improving the calculation and prediction efficiency; while adopting tetrahedral meshes can improve the corrosion prediction accuracy of the metal contact surface.

[0019] Further, the setting of the physical field of the secondary current distribution of the geometric model is specifically as follows:

[0020] Set the reference electrode potential and discretize the electrolyte potential using linear elements;

[0021] Select the geometric model and set the boundary conditions of the geometric model;

[0022] According to the boundary conditions, calculate the electrode domain potential of the geometric model.

[0023] Further, the selection of the geometric model and the setting of the boundary conditions of the geometric model are specifically as follows:

[0024] Among them, the geometric model includes: a first region and a second region; the boundary conditions include: a first boundary condition, a second boundary condition, and a third boundary condition;

[0025] Set the first boundary condition of the upper surface of the first region as the electrode current; set the second boundary condition of the lower surface of the second region as electrical grounding; set the third boundary condition of the outer surface of the geometric model as the electrode current density; set the initial value of the electrolyte potential of the geometric model.

[0026] The present invention calculates and obtains the electrode domain potential through the setting of the electrode potential, the discretization of the electrolyte potential, and the setting of the boundary conditions, which is used to calculate the surface current distribution in the electrochemical reaction of the metal lap joint component and realize the quantitative processing of corrosion prediction.

[0027] Further, the setting of the current distribution-shell physical field of the geometric model is specifically as follows:

[0028] Set the reference electrode potential and discretize the electrolyte potential using quadratic elements;

[0029] Set the boundary of the geometric model as the electrolyte domain, and calculate the electrolyte thickness and electrolyte conductivity according to the first empirical formula and the second empirical formula;

[0030] Electrode phases are set for the boundaries of the geometric model, and the electrolyte potential is calculated based on the electrolyte thickness and electrolyte conductivity.

[0031] After setting the electrode potential and electrolyte potential, the present invention obtains the electrolyte thickness and electrolyte conductivity through empirical formulas to simulate the ion flow conduction along the surface tangent, thereby avoiding meshing the electrolyte liquid layer on the three-dimensional surface and improving the corrosion prediction efficiency.

[0032] Furthermore, the first empirical formula is:

[0033] σ=48250.20-287264.66RH+683394.19RH 2 -811693.63RH 3 +481365.72RH 4 -114051.78RH 5 ;

[0034] Where σ is the electrolyte conductivity and RH is the relative humidity;

[0035]

[0036] Where s is the electrolyte thickness and tF is the thickness factor.

[0037] Furthermore, the electrode phase setting for the boundary of the geometric model is specifically as follows:

[0038] Wherein, the geometric model includes: a first region and a second region;

[0039] Setting the surface of the first region as an electrode surface, setting an external potential and selecting the potential as an electrode phase condition; setting the surface of the second region as an electrode surface, setting an external potential and selecting the potential as an electrode phase condition;

[0040] The anode Tafel equation is selected as the electrode kinetic expression of the first electrode reaction; the cathode Tafel equation is selected as the electrode kinetic expression of the second electrode reaction.

[0041] Furthermore, the corrosion rate is expressed as:

[0042]

[0043] in, is the corrosion rate, i is the local current density, n is the chemical equivalent coefficient, M is the relative molecular mass, F is the Faraday constant, and ρ is the metal density.

[0044] On the other hand, an embodiment of the present invention provides a method and device for predicting the corrosion of a metal lap joint component, including: a parameter acquisition module, a model establishment module, a first calculation module, and a second calculation module;

[0045] The parameter acquisition module is used to acquire the structural parameters and material parameters of the metal lap joint component;

[0046] The model establishment module is used to establish a geometric model corresponding to the metal lap joint component according to the structural parameters;

[0047] The first calculation module is used to establish a geometric model according to the structural parameters and material parameters, set the material and physical field of the geometric model, and calculate the current density distribution;

[0048] The second calculation module is used to calculate the corrosion rate of the metal lap joint component according to the current density distribution, and generate a corrosion rate distribution map to achieve prediction.

[0049] After establishing a geometric model through structural parameters and completing material testing of the combined model through material parameters in the present invention, the physical field, mesh, and solver are set for simulation to obtain the current density distribution, thereby realizing the quantification of the corrosion process; in addition, according to the current density distribution, the corrosion rate is calculated and a corrosion rate distribution map is generated, realizing the prediction of the corrosion process through modeling and simulation calculations based on structural parameters and material parameters, reducing the operation and maintenance workload, and improving the prediction efficiency. Description of the Drawings

[0050] Figure 1 It is a schematic flow chart of an embodiment of the method for predicting the corrosion of a metal lap joint component provided by the present invention;

[0051] Figure 2 It is a schematic diagram of an embodiment of the geometric model of the metal lap joint component provided by the present invention;

[0052] Figure 3 It is a schematic diagram of an embodiment of the corrosion rate distribution of the metal lap joint component provided by the present invention;

[0053] Figure 4 It is a schematic flow chart of another embodiment of the method for predicting the corrosion of a metal lap joint component provided by the present invention;

[0054] Figure 5 It is a schematic diagram of an embodiment of the mesh division of the metal lap joint component provided by the present invention;

[0055] Figure 6 It is a schematic diagram of an embodiment of the corrosion current density distribution of the metal lap joint component provided by the present invention;

[0056] Figure 7 Schematic structural diagram of an embodiment of the prediction device for corrosion of metal lap joints provided by the present invention. Detailed implementation manners

[0057] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are only a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0058] Embodiment 1

[0059] Please refer to Figure 1 , which is a schematic flowchart of an embodiment of the prediction method for corrosion of metal lap joints provided by an embodiment of the present invention, mainly including steps 101-103, specifically as follows:

[0060] Step 101: Collect the structural parameters and material parameters of the metal lap joint.

[0061] In this embodiment, the collection of the structural parameters and material parameters of the metal lap joint is specifically:

[0062] Obtain the structural parameters of the metal lap joint according to on-site measurement of the metal lap joint or the design drawing of the metal lap joint; obtain the material parameters of the metal lap joint according to the product parameters of the metal lap joint.

[0063] In this embodiment, the material parameters include: elastic modulus, Poisson's ratio, density, conductivity, relative magnetic permeability, coefficient of thermal expansion, constant-pressure heat capacity, relative nodal dielectric constant, thermal conductivity.

[0064] The structural parameters of the present invention are from the metal lap joint or the design drawing of the metal lap joint, while the material parameters are mainly from the product parameters of the metal lap joint. These two types of parameters are used for subsequent geometric model modeling and material setting, and no additional parameter collection and measurement are required to complete the calculation of current distribution and corrosion rate, improving the prediction efficiency.

[0065] Step 102: Establish a geometric model according to the structural parameters and material parameters, set the material and physical fields of the geometric model, and calculate the current density distribution.

[0066] Please refer to Figure 2 , which is a schematic diagram of an embodiment of the geometric model of the metal lap joint provided by the present invention. Among them, each part of the geometric model can be set as different materials. Figure 2The geometric model therein is mainly composed of the parts made of copper conductors and the parts made of aluminum conductors which are lapped; in addition, the materials of the various parts of the geometric model can be set according to the material parameters obtained in the previous step.

[0067] In this embodiment, since the corrosion caused by the electrochemical reaction of the metal lapping component is mainly caused by the connection of different metals with potential differences, when predicting the corrosion of each part of the geometric model corresponding to the metal lapping component, according to the material parameters, the materials of each part of the geometric model can be set.

[0068] Step 104: Calculate the corrosion rate of the metal lapping component according to the current density distribution, and generate a corrosion rate distribution map to achieve prediction.

[0069] In this embodiment, the expression of the corrosion rate is:

[0070]

[0071] where, is the corrosion rate, i is the local current density, n is the chemical equivalent coefficient, M is the relative molecular mass, F is the Faraday constant, ρ is the metal density; among them, the value of the Faraday constant is 96485 C / mol; when the materials of the metal lapping component are copper and aluminum, for aluminum alloy, the chemical equivalent coefficient is equal to 3, the relative molecular mass is the relative molecular mass of aluminum, and the metal density is the aluminum alloy density.

[0072] Please refer to Figure 3 , which is a schematic diagram of an embodiment of the corrosion rate distribution of the metal lapping component provided by the present invention, wherein the unit representing the corrosion rate is m / s, that is, the corrosion depth per second.

[0073] Please refer to Figure 4 , which is a schematic flow diagram of another embodiment of the method for predicting the corrosion of the metal lapping component provided by the present invention, mainly including steps 201-205, specifically as follows:

[0074] Step 201: Establish a geometric model corresponding to the metal lapping component according to the structural parameters.

[0075] In this embodiment, by measuring the metal lapping component or the design drawing of the metal lapping component on site, the structural dimensions of the metal lapping component can be obtained, and according to the structural dimensions, a geometric model can be established by using COMSOL Multiphysics simulation software.

[0076] Step 202: Set the materials of the various parts of the geometric model according to the material parameters.

[0077] In this embodiment, the metal lap joints where electrochemical reactions occur and thus corrosion occurs are often composed of lap joints of different metal materials. Therefore, after the geometric model is built, the materials of each part of the geometric model can be set. For example, select the part corresponding to the copper plate in the geometric model and set the material of this part to copper; select the part corresponding to the aluminum plate in the geometric model and set the material of this part to aluminum.

[0078] Step 203: Set the physical field of the secondary current distribution of the geometric model; set the physical field of the current distribution - shell of the geometric model.

[0079] In this embodiment, setting the physical field of the secondary current distribution of the geometric model specifically includes: setting the reference electrode potential and discretizing the electrolyte potential using linear elements; selecting the geometric model and setting the boundary conditions of the geometric model; calculating the electrode domain potential of the geometric model according to the boundary conditions.

[0080] In this embodiment, the reference electrode potential of the material is set to 0V.

[0081] In this embodiment, the calculation formula of the electrode domain potential is as follows:

[0082]

[0083]

[0084] where φ s is the electrode domain potential, i s is the electrode current density vector, with the unit of A / m 2 ; σ s is the conductivity, with the unit of S / m.

[0085] In this embodiment, selecting the geometric model and setting the boundary conditions of the geometric model specifically includes: where the geometric model includes: a first region and a second region; the boundary conditions include: a first boundary condition, a second boundary condition, and a third boundary condition; set the first boundary condition on the upper surface of the first region as the electrode current; set the second boundary condition on the lower surface of the second region as electrical grounding; set the third boundary condition on the outer surface of the geometric model as the electrode current density; set the initial value of the electrolyte potential of the geometric model.

[0086] In this embodiment, the first region can be a copper plate, and the second region can be an aluminum plate; the initial value of the electrolyte potential can be 0V, and the electric potential is 0V.

[0087] Through the setting of the electrode potential, the discretization of the electrolyte potential, and the setting of the boundary conditions, the potential of the electrode domain is calculated in the present invention, which is used to calculate the surface current distribution in the electrochemical reaction of metal lap components and realize the quantitative treatment of corrosion prediction.

[0088] In this embodiment, the setting of the current distribution-shell physical field of the geometric model is specifically as follows: set the reference electrode potential, and discretize the electrolyte potential using quadratic elements; set the boundary of the geometric model as the electrolyte domain, and calculate the electrolyte thickness and electrolyte conductivity according to the first empirical formula and the second empirical formula; set the electrode phase for the boundary of the geometric model, and calculate the electrolyte potential according to the electrolyte thickness and electrolyte conductivity.

[0089] In this embodiment, the first empirical formula is:

[0090] σ = 48250.20 - 287264.66RH + 683394.19RH 2 -811693.63RH<x 3 +481365.72RH 4 -114051.78RH 5 ;

[0091] where σ is the electrolyte conductivity and RH is the relative humidity;

[0092]

[0093] where s is the electrolyte thickness and tF is the thickness factor.

[0094] In this embodiment, the calculation formula of the electrolyte potential is as follows:

[0095]

[0096]

[0097] where φ l is the electrolyte potential of the electrolyte domain, s is the electrolyte thickness, and σ l is the electrolyte conductivity.

[0098] In this embodiment, the electrode phase setting for the boundary of the geometric model is specifically as follows: wherein, the geometric model includes a first region and a second region; the surface of the first region is set as the electrode surface, an external potential is set and the electric potential is selected as the electrode phase condition; the surface of the second region is set as the electrode surface, an external potential is set and the electric potential is selected as the electrode phase condition; the anodic Tafel equation is selected as the electrode kinetics expression for the first electrode reaction; the cathodic Tafel equation is selected as the electrode kinetics expression for the second electrode reaction.

[0099] Step 204: Select a tetrahedral mesh to mesh the geometric model.

[0100] In this embodiment, the mesh size of the tetrahedral mesh at the connection interface between the first region and the second region can be less than or equal to 1 / 2 of the overall mesh size, thereby improving the prediction accuracy of the corrosion rate at the contact surface between the first region and the second region; in addition, in the mesh element size setting, the mesh element size can be calibrated to general physics.

[0101] Please refer to Figure 5 , which is a schematic diagram of an embodiment of the mesh division of the metal lap joint component provided by the present invention. Among them, the tetrahedral mesh is selected for the mesh setting. The tetrahedral mesh has good geometric adaptability and is suitable for components with complex geometric shapes and large area ratios; therefore, for the metal lap joint component, using the tetrahedral mesh for mesh division can improve the accuracy of subsequent simulation and calculation.

[0102] Step 205: Set a solver and calculate the meshed geometric model according to the solver to obtain the current density distribution.

[0103] In this embodiment, the solver includes a transient solver and a steady-state solver; to calculate the corrosion rate of the metal lap joint component, the stable temperature under specific current and sunlight intensity needs to be obtained, so the steady-state solver is selected for calculation; in addition, the current density distribution includes a corrosion current density distribution and a redox density distribution.

[0104] Please refer to Figure 6 , which is a schematic diagram of an embodiment of the corrosion current density distribution of the metal lap joint component provided by the present invention. After selecting the steady-state solver for calculation, post-processing the results can obtain Figure 6 the corrosion current density distribution shown; in addition, post-processing the calculation results can also obtain the redox density distribution.

[0105] The present invention sets the materials of each part of the geometric model according to material parameters, and by setting the physical field of the secondary current distribution, after setting the solver as a steady-state solver, it can calculate the surface current distribution of the metal lap joint component and quantify the intermediate process of corrosion rate calculation; adopts the current distribution-shell physical field to simulate the ion flow along the surface, avoiding mesh division of the electrolyte liquid layer on the three-dimensional surface, improving the calculation and prediction efficiency; and adopting tetrahedral meshes can improve the corrosion prediction accuracy of the metal contact surface.

[0106] Please refer to Figure 7 , which is a schematic structural diagram of an embodiment of the prediction device for corrosion of a metal lap joint component provided by the present invention, mainly including: a parameter acquisition module 301, a first calculation module 302, and a second calculation module 303.

[0107] In this embodiment, the parameter acquisition module 301 is used to acquire the structural parameters and material parameters of the metal lap joint component.

[0108] In this embodiment, the parameter acquisition module 301 includes: a first parameter acquisition unit and a second parameter acquisition unit; the first parameter acquisition unit is used to obtain the structural parameters of the metal lap joint component according to on-site measurement of the metal lap joint component or the design drawing of the metal lap joint component; the second parameter acquisition unit is used to obtain the material parameters of the metal lap joint component according to the product parameters of the metal lap joint component.

[0109] The first calculation module 302 is used to establish a geometric model according to the structural parameters and material parameters, and set the materials and physical fields of the geometric model, and calculate the current density distribution.

[0110] In this embodiment, the first calculation module 302 includes: a model establishment unit, a material setting unit, a first physical field setting unit, a second physical field setting unit, a mesh division unit, and a calculation unit; the model establishment unit is used to establish a geometric model corresponding to the metal lap joint component according to the structural parameters; the material setting unit is used to set the materials of each part of the geometric model according to the material parameters; the first physical field setting unit is used to set the physical field of the secondary current distribution of the geometric model; the second physical field setting unit is used to set the current distribution-shell physical field of the geometric model; the mesh division unit is used to select tetrahedral meshes to perform mesh division on the geometric model; the calculation unit is used to set the solver and calculate the meshed geometric model according to the solver to obtain the current density distribution.

[0111] In this embodiment, the first physical field setting unit includes: a first potential setting subunit, a boundary condition setting subunit, and a first potential calculation unit; the first potential setting subunit is used to set the reference electrode potential and discretize the electrolyte potential using a linear unit; the boundary condition setting subunit is used to select the geometric model and set the boundary conditions of the geometric model; the first potential calculation unit is used to calculate the electrode domain potential of the geometric model according to the boundary conditions.

[0112] In this embodiment, the second physical field setting unit includes: a second potential setting subunit, a boundary setting unit, and a second potential calculation unit; the second potential setting subunit is used to set the reference electrode potential and discretize the electrolyte potential using a quadratic unit; the boundary setting unit is used to set the boundary of the geometric model as the electrolyte domain and calculate the electrolyte thickness and electrolyte conductivity according to the first empirical formula and the second empirical formula; the second potential calculation unit is used to perform electrode phase setting on the boundary of the geometric model and calculate the electrolyte potential according to the electrolyte thickness and electrolyte conductivity.

[0113] The second calculation module 303 is used to calculate the corrosion rate of the metal lap joint component according to the current density distribution and generate a corrosion rate distribution map for prediction.

[0114] After establishing a geometric model through structural parameters and completing material testing of the combined model through material parameters in the present invention, a physical field, a mesh, and a solver are set for simulation to obtain the current density distribution, thereby realizing the quantification of the corrosion process; in addition, according to the current density distribution, the corrosion rate is calculated and a corrosion rate distribution map is generated, realizing the prediction of the corrosion process through modeling and simulation calculations with structural parameters and material parameters, reducing the operation and maintenance workload and improving the prediction efficiency.

[0115] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. In particular, it is pointed out that for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for predicting corrosion of a metal lap joint component, characterized in that, Including: Collecting the structural parameters and material parameters of the metal lap joint component; According to the structural parameters and material parameters, establishing a geometric model, setting the material and physical fields of the geometric model, and calculating the current density distribution, specifically: establishing a geometric model corresponding to the metal lap joint component according to the structural parameters; setting the materials of each part of the geometric model according to the material parameters; setting the physical field of the secondary current distribution of the geometric model; Setting the physical field of the current distribution - shell of the geometric model; selecting a tetrahedral mesh to perform mesh division on the geometric model; setting a solver, and calculating the mesh - divided geometric model according to the solver to obtain the current density distribution; According to the current density distribution, the corrosion rate of the metal lap joint component is calculated, and a corrosion rate distribution map is generated for prediction; wherein, the expression of the corrosion rate is: ; wherein, is the corrosion rate, is the local current density, is the chemical equivalent coefficient, is the relative molecular mass, is the Faraday constant, is the metal density.

2. The method for predicting corrosion of the metal lap joint component according to claim 1, wherein, The collecting of the structural parameters and material parameters of the metal lap joint component is specifically: Obtaining the structural parameters of the metal lap joint component according to on - site measurement of the metal lap joint component or the design drawing of the metal lap joint component; obtaining the material parameters of the metal lap joint component according to the product parameters of the metal lap joint component.

3. The method for predicting corrosion of the metal lap joint component according to claim 1, wherein, The setting of the physical field of the secondary current distribution of the geometric model is specifically: Setting the reference electrode potential and discretizing the electrolyte potential using linear elements; Selecting the geometric model and setting the boundary conditions of the geometric model; Calculating the electrode domain potential of the geometric model according to the boundary conditions.

4. The method for predicting corrosion of the metal lap joint component according to claim 3, wherein The selecting of the geometric model and setting the boundary conditions of the geometric model is specifically: Among them, the geometric model includes: a first region and a second region; the boundary conditions include: a first boundary condition, a second boundary condition, and a third boundary condition; Setting the first boundary condition on the upper surface of the first region as the electrode current; setting the second boundary condition on the lower surface of the second region as electrical grounding; setting the third boundary condition on the outer surface of the geometric model as the electrode current density; setting the initial value of the electrolyte potential of the geometric model.

5. The method for predicting corrosion of the metal lap joint component according to claim 1, wherein, The setting of the physical field of the current distribution - shell of the geometric model is specifically: Setting the reference electrode potential and discretizing the electrolyte potential using quadratic elements; Setting the boundary of the geometric model as the electrolyte domain, and calculating the electrolyte thickness and electrolyte conductivity according to a first empirical formula and a second empirical formula; Performing electrode phase setting on the boundary of the geometric model, and calculating the electrolyte potential according to the electrolyte thickness and electrolyte conductivity.

6. The method for predicting corrosion of the metal lap joint component according to claim 5, wherein, The first empirical formula is: ； Among them, is the electrolyte conductivity, is the relative humidity; ； Among them, is the electrolyte thickness, is the thickness factor.

7. The method for predicting corrosion of the metal lap joint component according to claim 5, characterized in that, The performing of electrode phase setting on the boundary of the geometric model is specifically: Among them, the geometric model includes: a first region and a second region; Setting the surface of the first region as the electrode surface, setting the external potential and selecting the electric potential as the electrode phase condition; setting the surface of the second region as the electrode surface, setting the external potential and selecting the electric potential as the electrode phase condition; Selecting the anodic Tafel equation as the electrode kinetic expression for the first electrode reaction; selecting the cathodic Tafel equation as the electrode kinetic expression for the second electrode reaction.

8. A prediction device for corrosion of a metal lap joint component, characterized in that, Including: Parameter acquisition module, first calculation module and second calculation module; The parameter acquisition module is used to acquire the structural parameters and material parameters of the metal lap joint components; The first calculation module is used to establish a geometric model according to the structural parameters and material parameters, and set the materials and physical fields of the geometric model, and calculate the current density distribution. Specifically: establish a geometric model corresponding to the metal lap joint component according to the structural parameters; set the materials of each part of the geometric model according to the material parameters; set the physical field of the secondary current distribution of the geometric model; Set the current distribution-shell physical field of the geometric model; select tetrahedral mesh to perform mesh division on the geometric model; set the solver, and calculate the meshed geometric model according to the solver to obtain the current density distribution; The second calculation module is used to calculate the corrosion rate of the metal lap joint component according to the current density distribution and generate a corrosion rate distribution map for prediction; wherein, the expression of the corrosion rate is as follows: ; wherein, is the corrosion rate, is the local current density, is the chemical equivalent coefficient, is the relative molecular mass, is the Faraday constant, is the metal density.

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