Solid hair metal joint structure safety margin assessment method and system based on phase field method
The safety margin evaluation of the metal joint structure is solved through the phase field method, and the safety problem of composite shell solid rocket engines under complex stress states is achieved, and the integrity analysis and optimization design of metal joints are realized.
Patent Information
- Application Number
- CN202510673708.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-23
- Publication Date
- 2025-07-29
AI Technical Summary
The prior art is difficult to effectively evaluate the safety margin and failure mechanism of metal joints of composite shell solid rocket engines under complex stress states, and traditional methods are difficult to fully describe their damage and fracture behavior.
The phase field method is used for geometric modeling, mesh division, physical model setting and finite element simulation. Combined with elastic mechanics and fracture phase field model, the phase field variable distribution and evolution of metal joints are analyzed, and the cracking load and safety margin are determined.
The integrity analysis of the metal joint structure under complex stress states is achieved, and its safety margin and crack propagation behavior can be accurately evaluated, and the structural optimization design can be guided.
Smart Images
Figure CN120387346A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of method inventions, and particularly relates to a method and system for evaluating the safety margin of a solid rocket motor metal joint structure based on the phase field method. Background Art
[0002] Solid rocket motors are widely used in the aerospace field due to their advantages such as good mobility, high reliability, and easy maintenance. Among them, a composite shell solid rocket motor is composed of parts such as a carbon fiber epoxy composite wound cylinder, a head, a metal joint, and a skirt. In particular, joints are installed at the front and rear polar holes of the shell and are combined with connection structures such as snap rings and retaining rings to connect components such as igniters and nozzles. At the same time, the joints are also used for opening reinforcement of the head. Therefore, the metal joint structure is an important load-bearing component during the operation of a solid rocket motor, and the reliability of its mechanical properties such as strength and stiffness needs to be ensured.
[0003] At present, traditional solid strength theories are no longer sufficient to adapt to the failure mechanism research of metal joints under complex stress states, and it is difficult to establish a corresponding safety margin evaluation method. Using a single fracture mechanics or damage mechanics theory, it is also difficult to completely obtain the damage and fracture behaviors of the metal joint structure under complex stress states.
[0004] To address the above problems, this patent constructs a safety margin evaluation method for the metal joint structure of a composite shell solid rocket motor based on the phase field method, which can be used for the failure mechanism research of typical joint structures under complex stress states, clarify the crack initiation and propagation mechanisms in the weak areas under structural loading, and obtain the corresponding crack initiation load. Summary of the Invention
[0005] To solve the above problems, the present invention provides a method and system for evaluating the safety margin of a solid rocket motor metal joint structure based on the phase field method. The present invention is applicable to the integrity analysis of the metal joint structure in a composite shell solid rocket motor.
[0006] To achieve the above object, the present invention adopts the following technical solutions:
[0007] A method for evaluating the safety margin of a solid rocket motor metal joint structure based on the phase field method, comprising:
[0008] Step 1: Perform geometric modeling and mesh division on the research object;
[0009] Step 2: Set the physical models and related parameters required for each part of the research object on the basis of Step 1;
[0010] Step 3: Set boundary conditions for the model in Step 2 and perform finite element simulation. When the working conditions meet the given load conditions, end the simulation and output the results;
[0011] Step 4: Determine the cracking load and safety margin of the metal joint based on the distribution and evolution of the phase field variables in the result file of Step 3.
[0012] A further improvement of the present invention is that in Step 1, geometric modeling and mesh division are performed on the research object, including:
[0013] Perform geometric modeling on the research object: including a housing, a plug, a metal joint, and a snap ring;
[0014] Use hexahedral mesh elements to perform mesh division on the structure: use hexahedral mesh elements to discretize the geometric model, and perform mesh refinement on the metal joint part to analyze the distribution of phase field variables.
[0015] A further improvement of the present invention is that in Step 2, physical models and related parameters required for each part of the research object are set on the basis of Step 1, including:
[0016] Set the physical models and related parameters required for each part of the research object: For the research object obtained in Step 1, an elastic mechanics model is applied to the housing part, and an elastoplastic mechanics and fracture phase field model is applied to the metal joint part; both the metal joint and the housing need to set conventional mechanical parameters, namely Young's modulus E and Poisson's ratio v, while the former additionally requires the initial yield stress σ0 and plastic modulus H related to plastic deformation ′ , as well as the regularization parameter l related to the phase field and the fracture toughness G IC ; The phase field regularization parameter l is used to regularize the surface energy function and is closely related to the width of the smeared crack.
[0017] A further improvement of the present invention is that the selection of the regularization parameter l is related to the characteristic scale of the current research object on the one hand, and to E, G of the material IC and the critical stress σ c on the other hand, especially when the crack surface geometry function adopts the AT-2 equation.
[0018] A further improvement of the present invention is that in Step 3, boundary conditions are set for the model in Step 2 and finite element simulation is performed. When the working condition meets the given load condition, the simulation is ended and the results are output, including:
[0019] Set boundary conditions and perform finite element simulation. When the working condition meets the given load condition, end the simulation and output the results: Based on the mechanical model in Step 2, apply pressure boundaries to the inner boundaries of the housing, plug, and metal joint; at the same time, set displacement-related constraints on other boundaries of the research object; finally, perform finite element simulation after all settings are completed, and end the simulation when the internal pressure reaches the required load level; the output results include the distribution of basic displacement field variables and phase field variables, and also consider field variables such as equivalent stress, principal stress, and equivalent plastic strain.
[0020] A further improvement of the present invention lies in that in step 4, based on the distribution and evolution of the phase field variables in the result file of step 3, the cracking load and safety margin of the metal joint are determined, including:
[0021] Determine the cracking load and safety margin of the metal joint according to the distribution and evolution of the phase field variables: as the load level increases, local plastic deformation occurs in the snap ring groove of the metal joint and the crack driving force gradually increases. When the local crack driving force is greater than the set softening energy threshold w0, the phase field variable d starts to evolve from 0. When the phase field variable approaches 1, it indicates that the metal joint has cracked;
[0022] The load corresponding to the cracking of the metal joint is the cracking load. Comparing the cracking load with the ultimate bearing capacity of the joint can be used to analyze the safety margin of the metal joint structure; to capture the crack propagation behavior inside the joint, the displacement field results of the inner boundary of the research object are used as displacement boundaries for further simulation analysis; as the displacement load increases, the crack gradually propagates into the joint, increasing the overall failure probability of the structure.
[0023] A safety margin evaluation system for a solid - hair metal joint structure based on the phase - field method includes:
[0024] A modeling and mesh generation module for geometric modeling and mesh generation of the research object;
[0025] A model and parameter setting module for setting the physical models and related parameters required for each part of the research object based on the modeling and mesh generation module;
[0026] A simulation module for setting boundary conditions for the model in the model and parameter setting module and performing finite - element simulation, and ending the simulation and outputting results when the working condition meets the given load condition;
[0027] A result determination module for determining the cracking load and safety margin of the metal joint based on the distribution and evolution of the phase field variables in the result file of the simulation module.
[0028] A further improvement of the present invention lies in that the modeling and mesh generation module for geometric modeling and mesh generation of the research object includes:
[0029] Perform geometric modeling for the research object: including a shell, a plug cover, a metal joint, and a snap ring;
[0030] Use hexahedral mesh elements for mesh generation of the structure: discretize the geometric model using hexahedral mesh elements, and perform mesh refinement on the metal joint part to analyze the distribution of phase field variables.
[0031] A further improvement of the present invention lies in that the model and parameter setting module sets the physical models and related parameters required for each part of the research object on the basis of the modeling and mesh generation module, including:
[0032] Set the physical models and related parameters required for each part of the research object: For the research object obtained in step 1, the elastic mechanics model is applied to its shell part, and the elastoplastic mechanics and fracture phase field model are applied to the metal joint part; Conventional mechanical parameters, namely Young's modulus E and Poisson's ratio v, need to be set for both the metal joint and the shell, while the former additionally requires the initial yield stress σ0 and plastic modulus H related to plastic deformation ′ , as well as the regularization parameter l related to the phase field and the fracture toughness G IC ; The phase field regularization parameter l is used to regularize the surface energy function and is closely related to the width of the smeared crack.
[0033] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the steps of the method for evaluating the structural safety margin of a solid rocket motor metal joint based on the phase field method.
[0034] Compared with the prior art, the present invention has at least the following beneficial technical effects:
[0035] 1. The present invention can consider the real material mechanical parameters and structural deformation behaviors in a composite shell solid rocket motor, and can ensure the rationality of the analysis results when guiding the design and optimization of engineering structures.
[0036] 2. The phase field method adopted by the present invention can analyze the complete process of structural failure and the load curve under complex stress states, and meet the deformation behaviors of the metal materials widely used in joints in engineering practice.
[0037] 3. By analyzing the variation of the crack evolution behavior in the joint with parameters such as size and load level, the present invention can obtain the fracture criterion of the metal joint under internal pressure load and establish a safety margin evaluation method with engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS
[0038] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.
[0039] Figure 1 It is a flowchart of the method for evaluating the structural safety margin of a solid rocket motor metal joint based on the phase field method.
[0040] Figure 2 It is a schematic diagram of a geometric model, where Figure 2 (a) is the geometric structure, Figure 2 (b) is the plug cover part, Figure 2 (c) is the metal joint part, Figure 2 (d) is the snap ring part, Figure 2 (e) is the housing part.
[0041] Figure 3 It is a schematic diagram of a mesh generation scheme, where Figure 3 (a) is the mesh distribution, Figure 3 (b) is the plug cover part, Figure 3 (c) is the metal joint part, Figure 3 (d) is the snap ring part, Figure 3 (e) is the housing part.
[0042] Figure 4 It is a schematic diagram of crack approximation based on the phase field method, where Figure 4 (a) is the discrete crack, Figure 4 (b) is the smeared crack.
[0043] Figure 5 It is a schematic diagram of the internal pressure boundary.
[0044] Figure 6 It is a schematic diagram of the phase field variable distribution of the metal joint - crack initiation.
[0045] Figure 7 It is a schematic diagram of the phase field variable distribution of the metal joint - crack propagation.
[0046] Figure 8 This is the structural block diagram of the structural safety margin evaluation system for the solid - fixed metal joint based on the phase field method of the present invention. Detailed implementation manners
[0047] In the following text, only some exemplary embodiments are briefly described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present invention. Therefore, the drawings and the description are regarded as exemplary rather than restrictive.
[0048] In the description of the present invention, it should be understood that when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.
[0049] It should also be understood that the terms used in the specification of the present invention are merely for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms.
[0050] It should be further understood that the term "and / or" used in the specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.
[0051] Schematic diagrams of various structures according to the disclosed embodiments of the present invention are shown in the drawings. These figures are not drawn to scale, where certain details are enlarged for the purpose of clear expression, and certain details may be omitted. The shapes of various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art can additionally design regions / layers with different shapes, sizes, and relative positions according to actual requirements.
[0052] The embodiments of the present invention will be described in detail below with reference to the drawings.
[0053] Embodiment 1
[0054] The method for evaluating the structural safety margin of a solid hair metal joint based on the phase field method provided by the present invention is applicable to the integrity and safety margin analysis of the metal joint structure in a composite shell solid rocket engine. This method can consider the working conditions of the composite shell solid rocket engine in a typical service environment, obtain the evolution of the phase field variable, i.e., the crack, in the metal joint structure under a complex stress state through simulation, thereby obtaining the corresponding load at crack initiation and determining the safety margin of the metal joint structure. The main steps are as follows:
[0055] Step 1: Perform geometric modeling on the research object and conduct mesh division. For example, for a certain composite shell solid rocket engine, its geometric model is as Figure 2 shown, including parts such as a shell, a plug cover, a metal joint, and a snap ring. Subsequently, hexahedral mesh elements are used to divide the structure into meshes, and the mesh distribution is as Figure 3 shown, and the mesh of the metal joint part is refined to analyze the distribution of the phase field variable.
[0056] Step 2: Set the physical models and related parameters required for each part of the research object. For the research object obtained in Step 1, the elastic mechanics model is applied to the shell part, while the elastoplastic mechanics and fracture phase field models are applied to the metal joint part. Conventional mechanical parameters such as Young's modulus E and Poisson's ratio v need to be set for parts such as the metal joint and the shell. Additionally, the former requires the initial yield stress σ0 and plastic modulus H related to plastic deformation ′ , as well as the regularization parameter l related to the phase field and the fracture toughness G IC . Parameters other than l are related to the material properties of the research object and can therefore be measured through experiments. The phase field regularization parameter l is used to regularize the surface energy function and is closely related to the width of the smeared crack, as shown in Figure 4 . The selection of l is related to the characteristic scale of the current research object on the one hand and E, G IC of the material and the critical stress σ c on the other hand, especially when the crack surface geometry function adopts the AT-2 equation.
[0057] Step 3: Set the boundary conditions and perform finite element simulation. End the simulation and output the results when the working conditions meet the given load conditions. Based on the mechanical models in Step 2, pressure boundaries are applied to the inner boundaries of the shell, the plug cover, and the metal joint, as shown in Figure 5 ; at the same time, displacement-related constraints are set for other boundaries of the research object. Finally, after all settings are completed, perform finite element simulation and end the simulation when the internal pressure reaches the required load level. The output results include the distributions of basic displacement field variables and phase field variables, and additional field variables such as equivalent stress, principal stress, and equivalent plastic strain can also be considered.
[0058] Step 4: Determine the cracking load and safety margin of the metal joint based on the distribution and evolution of the phase field variables. For example: Taking the research object shown in Figure 2 as an example, as the load level increases, local plastic deformation occurs in the snap ring groove of the metal joint and the crack driving force gradually increases. When the crack driving force is greater than the set softening energy threshold w0, the phase field variable d starts to evolve from 0. When the phase field variable approaches 1, it indicates that cracking has occurred in the metal joint, as shown in Figure 6 .
[0059] The load corresponding to the cracking of the metal joint is the cracking load. Comparing the cracking load with the ultimate bearing capacity of the joint can be used to analyze the safety margin of the metal joint structure. To capture the crack propagation behavior in the joint, the displacement result calculated using the pressure load without considering the coupling of the phase field variable, that is, the displacement field result of the inner boundary of the research object, is used as the displacement boundary for another simulation analysis. The crack propagation behavior is shown in Figure 7 . As the displacement load increases, the crack gradually propagates into the joint, increasing the overall failure probability of the structure.
[0060] Example 2
[0061] As Figure 8 shown, the system for evaluating the structural safety margin of a hair-fixing metal joint based on the phase-field method provided by the present invention includes:
[0062] A modeling and mesh generation module for geometric modeling and mesh generation of the research object;
[0063] A model and parameter setting module for setting the physical models and related parameters required for each part of the research object based on the modeling and mesh generation module;
[0064] A simulation module for setting boundary conditions for the model in the model and parameter setting module and performing finite element simulation, and ending the simulation and outputting results when the working condition meets the given load condition;
[0065] A result determination module for determining the cracking load and safety margin of the metal joint based on the distribution and evolution of the phase-field variables in the result file of the simulation module.
[0066] Example 3
[0067] A computer-readable storage medium provided by the present invention, wherein the computer-readable storage medium stores a computer program, and the computer program implements the steps of the method for evaluating the structural safety margin of a hair-fixing metal joint based on the phase-field method when executed by a processor.
[0068] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0069] The present application is described with reference to the flowcharts and / or block diagrams of methods, systems, and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, as well as the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a system for implementing the specified functions in one Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.
[0070] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction device that implements the functions specified in one or more of the processes Figure 1 one or more of the processes and / or boxes Figure 1 specified in one or more of the boxes.
[0071] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more of the processes Figure 1 one or more of the processes and / or boxes Figure 1 specified in one or more of the boxes.
[0072] The foregoing has shown and described the basic principles, principal features and advantages of the present invention. To those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and that without departing from the spirit or essential characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, in whatever aspect, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description. Accordingly, all changes that fall within the meaning and range of the equivalents of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claim concerned.
[0073] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment contains only a single technical solution. This narrative manner of the specification is merely for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.
Claims
1. A method for evaluating the structural safety margin of a solid hair metal joint based on the phase field method, characterized in that, Including: Step 1: Conduct geometric modeling and mesh generation for the research object; Step 2: Based on Step 1, set the physical models and related parameters required for each part of the research object; Step 3: Set boundary conditions for the model in Step 2 and perform finite element simulation. End the simulation and output the results when the working conditions meet the given load conditions; Step 4: Determine the crack initiation load and safety margin of the metal joint based on the distribution and evolution of the phase field variables in the result file of Step 3.
2. The method for evaluating the structural safety margin of a hair-fixing metal joint based on the phase field method according to claim 1, wherein In the said Step 1, conducting geometric modeling and mesh generation for the research object includes: Conduct geometric modeling for the research object: including a shell, a plug, a metal joint, and a snap ring; Use hexahedral mesh elements to perform mesh generation on the structure: Discretize the geometric model using hexahedral mesh elements, and refine the mesh of the metal joint part to analyze the distribution of phase field variables.
3. The method for evaluating the structural safety margin of a solid hair metal joint based on the phase field method according to claim 2, characterized in that In the said Step 2, setting the physical models and related parameters required for each part of the research object based on Step 1 includes: Set the physical models and related parameters required for each part of the research object: For the research object obtained in Step 1, the elastic mechanics model is applied to its shell part, and the elastoplastic mechanics and fracture phase field models are applied to the metal joint part; Conventional mechanical parameters, namely Young's modulus E and Poisson's ratio v, need to be set for both the metal joint and the shell, while the former additionally requires the initial yield stress σ0 and plastic modulus H related to plastic deformation ′ , as well as the regularization parameter l related to the phase field and the fracture toughness G IC ; The phase field regularization parameter l is used to regularize the surface energy function and is closely related to the width of the smeared crack.
4. The method for evaluating the structural safety margin of a hair-fixing metal joint based on the phase field method according to claim 3, wherein The selection of the regularization parameter l is related to the characteristic scale of the current research object on the one hand and the E and G of the material IC and the critical stress σ c on the other hand, especially when the crack surface geometry function adopts the AT-2 equation.
5. The method for evaluating the structural safety margin of a hair-fixing metal joint based on the phase field method according to claim 1, wherein In the said Step 3, setting boundary conditions for the model in Step 2 and performing finite element simulation. End the simulation and output the results when the working conditions meet the given load conditions includes: Set boundary conditions and perform finite element simulation. End the simulation and output the results when the working conditions meet the given load conditions: Based on the mechanical model in Step 2, apply pressure boundaries to the inner boundaries of the shell, the plug, and the metal joint; at the same time, set displacement-related constraints for other boundaries of the research object; finally, perform finite element simulation after all settings are completed, and end the simulation when the internal pressure reaches the required load level; The output results include the distribution of basic displacement field variables and phase field variables, and also consider field variables such as equivalent stress, principal stress, and equivalent plastic strain.
6. The method for evaluating the structural safety margin of a solid hair metal joint based on the phase field method according to claim 1, characterized in that, In the said Step 4, determining the crack initiation load and safety margin of the metal joint based on the distribution and evolution of the phase field variables in the result file of Step 3 includes: Determine the crack initiation load and safety margin of the metal joint according to the distribution and evolution of the phase field variables: As the load level increases, local plastic deformation occurs in the snap ring groove of the metal joint and the crack driving force gradually increases. When the local crack driving force is greater than the set softening energy threshold w0, the phase field variable d starts to evolve from 0. When the phase field variable approaches 1, it indicates that the metal joint has cracked; The load corresponding to the crack initiation of the metal joint is the crack initiation load. Comparing the crack initiation load with the ultimate bearing capacity of the joint can be used to analyze the safety margin of the metal joint structure; To capture the crack propagation behavior inside the joint, the displacement field results of the inner boundary of the research object are used as displacement boundaries to perform simulation analysis again; As the displacement load increases, the crack gradually propagates into the joint, increasing the overall failure probability of the structure.
7. A system for evaluating the structural safety margin of a solid-state metal joint based on the phase field method, characterized in that Including: A modeling and mesh generation module, which conducts geometric modeling and mesh generation for the research object; A model and parameter setting module, which sets the physical models and related parameters required for each part of the research object based on the modeling and mesh generation module; A simulation module, which sets boundary conditions for the model in the model and parameter setting module and performs finite element simulation. End the simulation and output the results when the working conditions meet the given load conditions; A result determination module determines the cracking load and safety margin of the metal joint based on the distribution and evolution of the phase field variables in the result file of the simulation module.
8. The safety margin evaluation system for the solid hair metal joint structure based on the phase field method according to claim 7, characterized in that The modeling and meshing module performs geometric modeling and meshing on the research object, including: Performing geometric modeling on the research object: including a shell, a plug cover, a metal joint, and a snap ring; Meshing the structure using hexahedral mesh elements: discretizing the geometric model using hexahedral mesh elements and densifying the mesh of the metal joint part to analyze the distribution of the phase field variables.
9. The structural safety margin evaluation system for a hair-fixing metal joint based on the phase-field method according to claim 8, wherein The model and parameter setting module sets the physical models and related parameters required for each part of the research object on the basis of the modeling and meshing module, including: Set the physical models and related parameters required for each part of the research object: For the research object obtained in step 1, the elastic mechanics model is applied to its shell part, and the elastoplastic mechanics and fracture phase field models are applied to the metal joint part; Conventional mechanical parameters, namely Young's modulus E and Poisson's ratio v, need to be set for both the metal joint and the shell, while the former additionally requires the initial yield stress σ0 and plastic modulus H related to plastic deformation ′ , as well as the regularization parameter l related to the phase field and the fracture toughness G IC ; The phase field regularization parameter l is used to regularize the surface energy function and is closely related to the width of the smeared crack.
10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the steps of the method for evaluating the structural safety margin of a solid-fired metal joint based on the phase field method according to any one of claims 1-6.