A Simulation Model for Delamination Defects in Double-Layer Coatings and a Method for Analyzing Mechanical Behavior
By building a double-layer coating delamination defect model in ABAQUS simulation software, the variation law of coating adhesion is simulated, which solves the problem that existing technologies cannot effectively analyze coating delamination defects, realizes simulation analysis and repair guidance of coating defects, and reduces experimental costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-11-25
- Publication Date
- 2026-04-03
AI Technical Summary
Existing technologies make it difficult to establish three-dimensional simulation models to simulate changes in coating adhesion and cannot effectively analyze delamination defects between two coating layers, leading to coating detachment that threatens flight safety and makes detection and repair difficult.
A delamination defect model of a double-layer coating was built using ABAQUS simulation software. By creating a cylindrical substrate and coating in ABAQUS simulation software, the delamination defect model was defined, and delamination defects of different sizes were simulated on cohesive elements to perform mechanical behavior analysis.
It enables simulation of coating adhesion under delamination defects of different sizes, guiding coating defect analysis, detection and repair, and reducing experimental exploration costs.
Smart Images
Figure CN115831287B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of simulation analysis technology, specifically to a method for building a simulation model of delamination defects in a double-layer coating and analyzing its mechanical behavior. Background Technology
[0002] Complex functional coating systems composed of multiple layers, interfaces, and materials are designed to prevent corrosion damage to aircraft skin, improve aircraft survivability and combat effectiveness, and therefore require high physical and mechanical properties and reliability. However, during service, delamination defects are prone to occur within multi-layered coating systems. These defects can lead to coating detachment, threatening flight safety. Because delamination defects are located within the coating, they are difficult to detect and repair visually. Therefore, it is necessary to conduct failure analysis of coating delamination defects and explore their impact on coating adhesion, providing a theoretical basis for coating defect analysis, detection, and repair.
[0003] In recent years, simulation analysis methods such as cohesive elements and extended finite element method have been widely used in the failure analysis of coating delamination defects. However, most of these methods focus on delamination defects between the coating and the substrate, with few simulation analyses of the interface between two coating layers. Furthermore, current research primarily uses two-dimensional simulation models, neglecting the creation of three-dimensional models to simulate the delamination process, thus failing to directly simulate the numerical changes in coating adhesion. Additionally, current research rarely incorporates pre-fabricated delamination defect models into the coating model, and the size of the delamination defect model cannot be modified. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention proposes a simulation model for delamination defects in double-layer coatings and a method for analyzing their mechanical behavior. This provides a rapid and convenient analytical method for analyzing coating delamination defects, helping to guide coating defect analysis, detection, and repair, and reducing experimental exploration costs.
[0005] The technical problem to be solved by this invention is achieved by the following technical solution:
[0006] A method for constructing a simulation model of delamination defects in a double-layer coating and analyzing its mechanical behavior is as follows:
[0007] Step (1) Based on the cylindrical substrate and the first and second coatings covering the cylindrical substrate, a 1:1 model is built in ABAQUS simulation software, including the construction of the cylindrical substrate, the construction of the coatings, and the definition of the layered defect model.
[0008] Step (II) In the Material Manager of the ABAQUS simulation software, establish the material properties of the matrix, the first coating layer, the second coating layer, and the cohesive element respectively;
[0009] Step (3): In the analysis module of the ABAQUS simulation software, open the analysis step manager to create an analysis step, and set the field output in the field output manager;
[0010] Step (4) Establish rigid body constraints in the constraint manager of the ABAQUS simulation software, and create boundary conditions in the boundary condition manager in the load module;
[0011] Step (5): In the job module of the ABAQUS simulation software, open the job manager, create a new job, and submit it. Then, in the job editing page, click the parallel tab to start the calculation.
[0012] Step (VI) Following the steps above, establish a layered defect model with a radius of 1-9 mm and simulate the drawing process. Then, analyze the simulation results to find that: defects with a radius of 1-5 mm have a small impact on the bonding force between the first coating and the second coating, while defects with a radius of 6-9 mm have a large impact on the bonding force between the first coating and the second coating.
[0013] Preferably, in step (i), the cylindrical substrate has dimensions of φ20mm×30mm, the first coating has a thickness of 0.5mm, and the second coating has a thickness of 0.06mm.
[0014] Preferably, the specific process of constructing the cylindrical base in step (i) is as follows:
[0015] Click the "Create Part" button in the Parts module of the ABAQUS simulation software, set the basic features of the model to a three-dimensional deformable solid, and select the stretching class;
[0016] Click on the sketch to enter the 2D planar drawing interface. Draw the planar view of the cylindrical base. Click the "Construct Circle" button to draw a circle with a radius of 10mm. After completing the section sketch, set the cylinder thickness to 30mm in the pop-up dialog box to complete the construction of the φ20mm×30mm cylindrical base.
[0017] Preferably, the specific process of coating construction in step (i) is as follows:
[0018] Create a reference line parallel to the central axis of the cylinder, and establish reference points along the side of the cylinder at vertical distances of 0.5 mm and 0.56 mm from the end face;
[0019] The cylinder is divided along the reference line and reference point to obtain a 3-layer cylinder. The first layer is a coating with a thickness of 0.5 mm, the second layer is a coating with a thickness of 0.06 mm, and the third layer is the substrate.
[0020] Preferably, the specific process of defining the layered defect model in step (i) is as follows:
[0021] Click on the sketch to enter the 2D drawing interface. Draw a circle of size 1-9mm concentric with the cylinder to assist in mesh division.
[0022] Click the "Create Mesh" button in the mesh step to generate a mesh;
[0023] To introduce delamination defects between the first and second coating layers, an offset layer is formed on the end face of the second coating layer using the offset command. The thickness of the layer is defined as 0. The cohesive unit represents the interface between the two coating layers.
[0024] Use the mesh editing tool to delete the mesh in the area with the same center diameter as the cylinder, representing the corresponding defect.
[0025] Preferably, the material properties of the cylindrical substrate, the first coating, and the second coating in step (ii) include elastic modulus and Poisson's ratio.
[0026] Preferably, the material properties of the cohesive unit in step (ii) include normal stress, shear stress, elastic modulus, x-direction shear modulus, y-direction shear modulus, and viscosity coefficient.
[0027] Preferably, the specific process of establishing the analysis step in step (iii) is as follows: create a general dynamic explicit analysis step step-1, set the maximum number of incremental steps to 1000, the maximum incremental step size to 0.05, and set the analysis time length to 1.
[0028] Preferably, the specific process of setting the field output in step (iii) is as follows: create F-Output-1, set the scope of action to the entire model, and set the output variable states to E, S, SDEG, and STATUS.
[0029] Preferably, the boundary conditions created in step (iv) include cylindrical substrate corner condition BC-1 and coating boundary condition BC-2.
[0030] The beneficial effects of this invention are:
[0031] 1. The simulation modeling object of this invention is the delamination defect between two coating layers, and it can simulate the variation law of the bonding force between the two coating layers under delamination defects of different sizes.
[0032] 2. In this invention, a cohesive unit with zero thickness is established between two coatings to represent the bonding surface between the two coatings. The mechanical behavior of the cohesive unit under the action of constraint force represents the bonding force between the two coatings.
[0033] 3. This invention simulates delamination defects with radii of 1 to 9 mm by deleting meshes with radii of 1 to 9 mm from the cohesive unit. The invention also simulates delamination defects of 1 to 9 mm in size and analyzes the simulation results to obtain the variation law of the bonding force between two coatings under delamination defects of different sizes.
[0034] 4. This invention helps guide the analysis, detection and repair of coating defects, and reduces the cost of experimental exploration. Attached Figure Description
[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments:
[0036] Figure 1 This is a flowchart of the present invention;
[0037] Figure 2 This is a schematic diagram of the simulation model in this invention;
[0038] Figure 3 This is a schematic diagram of the 2mm defect cohesive unit in this invention;
[0039] Figure 4 This is a schematic diagram of the simulation results of the present invention. Detailed Implementation
[0040] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with the accompanying drawings and embodiments.
[0041] like Figure 1 As shown, a simulation model for delamination defects in a double-layer coating and a method for analyzing its mechanical behavior are presented, with the following steps:
[0042] Step (1) Model Building
[0043] A 1:1 model was built in ABAQUS simulation software based on the actual shape and dimensions of the simulation object. The simulation object of this invention is a cylindrical substrate with a diameter of φ20mm × 30mm, covered with two layers: a first coating with a thickness of 0.5mm and a second coating with a thickness of 0.06mm. The model building process involves building the cylindrical substrate, building the coating layers, and introducing a layered defect model. For example... Figure 2 As shown.
[0044] 1) Base model construction
[0045] a. Click the Create Part button in the Parts module, set the basic features of the model to 3D deformable solid, and select the Extrusion class.
[0046] b. Click on the sketch to enter the 2D planar drawing interface, draw the planar view of the cylindrical base, and click the "Construct Circle" button to draw a circle with a radius of 10mm. After the section sketch is completed, set the cylinder thickness to 30mm in the pop-up dialog box to complete the construction of the φ20mm×30mm cylindrical base.
[0047] 2) Coating model construction
[0048] a. Create a reference line parallel to the central axis of the cylinder, and establish reference points along the side of the cylinder at vertical distances of 0.5mm and 0.56mm from the end face.
[0049] The cylinder is divided along the reference line and reference point to obtain a 3-layer cylinder. The first layer is a first coating with a thickness of 0.5 mm, the second layer is a second coating with a thickness of 0.06 mm, and the third layer is the substrate.
[0050] 3) Define a layered defect model
[0051] In this invention, the radius of the layered defect model is 1 to 9 mm. Taking the establishment of a layered defect with a radius of 2 mm as an example.
[0052] a. Click on the sketch to enter the 2D plane drawing interface, and draw a 2mm circle concentric with the cylinder to assist in mesh division.
[0053] b. Click the "Create Mesh" button in the mesh step to generate a mesh.
[0054] c. To introduce delamination defects between the first and second coating layers, an offset layer of cohesive elements is formed on the end face of the second coating layer using the offset command. The thickness of this cohesive element is defined as 0, and it represents the interface between the two coating layers. For example... Figure 3 As shown.
[0055] d. Use the mesh editing tool to delete the mesh of the circular area with a center diameter of 2mm, representing a defect of 2mm.
[0056] Step (II) Material Property Definition
[0057] The definition of material properties plays an important role in the simulation process. Material properties are established for the matrix, the first coating layer, the second coating layer, and the cohesive element in the material manager.
[0058] The elastic modulus and Poisson's ratio of the substrate, the first coating layer, and the second coating layer are shown in the table below:
[0059] matrix First coating layer Second coating elastic modulus 67000Mpa 3160Mpa 9120Mpa Poisson's ratio 0.3 0.3 0.3
[0060] The material properties of the cohesive unit are shown in the table below:
[0061]
[0062] Step (3) Establish the analysis step and set the field output.
[0063] When creating an analysis step, open the analysis step manager in the analysis step module, create a general dynamic explicit analysis step step-1, set the maximum number of increment steps to 1000, the maximum increment step size to 0.05, and set the analysis time length to 1.
[0064] Create F-Output-1 in the Field Output Manager, set its scope to the entire model, and set the output variable status to E, S, SDEG, and STATUS.
[0065] Step (4) Set boundary conditions and loading method
[0066] a. Apply rigid body constraints to the model, create a reference point RP-1, and set its position at a certain distance from the cylinder surface on the axis of the cylindrical model. Create rigid body constraints in the constraint manager and couple the microwave absorbing coating element to point RP-1.
[0067] b. Create boundary conditions in the load module. Create a new boundary condition BC-1 for the matrix. Open the boundary condition manager, click Create, select an analysis type named Symmetric / Antisymmetric / Completely Fixed in the mechanical category, select the bottom surface of the cylinder model, and select Completely Fixed, which means that the matrix is completely fixed.
[0068] c. Create boundary condition BC-2 for the absorbing coating in the Boundary Condition Manager. Select the displacement / rotation analysis type in the Mechanical category. Since RP-1 has established a coupling relationship with the first coating layer, select the reference point RP-1 and set the displacement in the U3 direction to 1, which means pulling the absorbing layer along the U3 direction (axial direction).
[0069] Step (5) Run the calculation
[0070] Enter the job module, click the job manager to create a new job. To improve efficiency, you can perform an overall check before submitting. Click data check, and check and debug the entire modeling and setup process according to the prompts and errors. When the debugging is complete and no errors are displayed, click the submit button. In the job editing page, click the parallel tab to start the calculation.
[0071] Step (VI) Simulation Result Analysis
[0072] Following the steps described above, establish delamination defect models with radii ranging from 1 to 9 mm and simulate the drawing process. For example... Figure 4 As shown.
[0073] The force required when the first coating layer just detaches from the surface of the second coating layer is the bonding force between the two. The simulation results of the bonding force under the defect model of 1-9mm are shown in the table below:
[0074]
[0075] Based on simulation results, when the radius of the delamination defect is 1–5 mm, the bonding force between the first and second coating layers changes little, remaining essentially the same as when there are no defects. This indicates that defects with a radius of 1–5 mm (i.e., the defect size accounts for 10%–50% of the total area) have a relatively small impact on the bonding force. When the defect radius is 6–9 mm, the bonding force gradually decreases, indicating that defects with a radius of 6–9 mm (60%–90%) have a significant impact on the bonding force between the two coating layers.
[0076] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely prisms of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.
Claims
1. A method for constructing a simulation model of delamination defects in a double-layer coating and analyzing its mechanical behavior, characterized in that: The steps are as follows: Step (1) Based on the cylindrical substrate and the first and second coatings covering the cylindrical substrate, a 1:1 model is built in ABAQUS simulation software, including the construction of the cylindrical substrate, the construction of the coatings, and the definition of the layered defect model. Step (2) In the Material Manager of the ABAQUS simulation software, establish the material properties of the matrix, the first coating layer, the second coating layer, and the cohesive element respectively; Step (3): In the analysis module of the ABAQUS simulation software, open the analysis step manager to create an analysis step, and set the field output in the field output manager; Step (4) Establish rigid body constraints in the constraint manager of the ABAQUS simulation software, and create boundary conditions in the boundary condition manager in the load module; Step (5): In the job module of the ABAQUS simulation software, open the job manager, create a new job and submit it. Then, in the job editing page, click the parallel tab to start the calculation. Step (VI) Following the steps above, establish a delamination defect model with a radius of 1-9 mm and simulate the drawing process. Then, analyze the simulation results to find that: defects with a radius of 1-5 mm have a small impact on the bonding force between the first coating and the second coating, while defects with a radius of 6-9 mm have a large impact on the bonding force between the first coating and the second coating. The specific process of constructing the cylindrical base in step (one) is as follows: Click the "Create Part" button in the Parts module of the ABAQUS simulation software, set the basic features of the model to a three-dimensional deformable solid, and select the stretching class; Click on the sketch to enter the 2D planar drawing interface, draw the planar view of the cylindrical base, click the construct circle button to draw a circle with a radius of 10mm; after the section sketch is completed, set the cylinder thickness to 30mm in the pop-up dialog box to complete the construction of the φ20mm×30mm cylindrical base; The specific process of coating construction in step (one) is as follows: Create a reference line parallel to the central axis of the cylinder, and establish reference points along the side of the cylinder at vertical distances of 0.5mm and 0.56mm from the end face; The cylinder is divided along the reference line and reference point to obtain a 3-layer cylinder. The first layer is a coating with a thickness of 0.5 mm, the second layer is a coating with a thickness of 0.06 mm, and the third layer is the substrate. The specific process of defining the layered defect model in step (one) is as follows: Click on the sketch to enter the 2D drawing interface. Draw a circle of size 1-9mm concentric with the cylinder to assist in mesh division. Click the "Create Mesh" button in the mesh step to generate a mesh; To introduce delamination defects between the first and second coating layers, an offset layer is formed on the end face of the second coating layer using the offset command. The thickness of the layer is defined as 0. The cohesive unit represents the interface between the two coating layers. Use the mesh editing tool to delete the mesh in the area with the same center diameter as the cylinder, representing the corresponding defect.
2. The method for constructing a simulation model and analyzing the mechanical behavior of a double-layer coating delamination defect according to claim 1, characterized in that: In step (1), the cylindrical substrate has dimensions of φ20mm×30mm, the thickness of the first coating is 0.5mm, and the thickness of the second coating is 0.06mm.
3. The method for constructing a simulation model and analyzing the mechanical behavior of a double-layer coating delamination defect according to claim 1, characterized in that: In step (ii), the material properties of the cylindrical substrate, the first coating, and the second coating include elastic modulus and Poisson's ratio.
4. The method for constructing a simulation model and analyzing the mechanical behavior of a double-layer coating delamination defect according to claim 1, characterized in that: The material properties of the cohesive unit in step (ii) include normal stress, shear stress, elastic modulus, x-direction shear modulus, y-direction shear modulus, and viscosity coefficient.
5. The method for constructing a simulation model and analyzing the mechanical behavior of a double-layer coating delamination defect according to claim 1, characterized in that: The specific process for establishing the analysis step in step (iii) is as follows: create a general dynamic explicit analysis step-1, set the maximum number of increment steps to 1000, the maximum increment step size to 0.05, and set the analysis time length to 1.
6. The method for constructing a simulation model and analyzing the mechanical behavior of a double-layer coating delamination defect according to claim 1, characterized in that: The specific process for setting the field output in step (iii) is as follows: create F-Output-1, set the scope of action to the entire model, and set the output variable states to E, S, SDEG, and STATUS.
7. The method for constructing a simulation model and analyzing the mechanical behavior of a double-layer coating delamination defect according to claim 1, characterized in that: The boundary conditions created in step (iv) include cylindrical substrate corner condition BC-1 and coating boundary condition BC-2.
Citation Information
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