A virtual impact experiment method for paint coating of a suspended launching device

Abstract

The present application relates to a kind of virtual impact test method of paint coating of suspension launching device, and particularly to a kind of virtual impact test method of paint coating of suspension launching device.The measurement range of experimental table is relatively narrow, the error of test result is greater, and the production cycle of paint coating is longer.The present application obtains the relationship of pit depth x about punch initial velocity V using transient dynamics theory and finite element simulation, and obtains the equation of pit depth x about punch initial velocity V by fitting;Build the impact test physical platform of paint coating of suspension launching device, obtain the pit depth x of paint coating when drop hammer falls from different height H, and obtain the equation of pit depth x about drop hammer height H by fitting;According to the analytical expression of punch initial velocity v about drop hammer height H, calculate the punch initial velocity under different height conditions, obtain the pit depth and residual stress under different height conditions;According to criterion, evaluate the strength of paint film.The confidence of impact strength of paint coating of suspension launching device is improved, the experimental period is shortened, and the experimental efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coating experiments of suspended launching devices, in particular to a virtual impact experiment method for paint coating of a suspended launching device. BACKGROUND

[0002] Coating is an important material for a suspended launching device, which can enhance the structural strength, improve the wear resistance and corrosion resistance of the structure, and thus improve the safety and reliability of the carrier. However, the coating may be subjected to the coupling of various complex and severe environments during service, thereby affecting the safety of the carrier, and the impact environment is particularly concerned.

[0003] At present, the impact strength of paint coating is mainly evaluated by physical experiment. The article "Analysis of Paint Coating Drying" (Mao Zhe, Yin Zhongqiu, Hu Jianfeng, published in Modern Paint and Coating, No. 9, 2023) combined with GB / T 8264-2008 "Painting Technology Terminology", and pointed out through analysis that the proportion of paint, the thickness of paint coating, temperature and the quality of paint will affect the performance of paint coating. Therefore, the impact strength of paint coating is easily affected by environmental factors such as temperature and humidity, thereby reducing the performance of the coating. According to the experimental results in the laboratory at present, the measurement range of the experimental table is narrow, and only the pit depth of the paint coating within a certain height range can be measured, and the lower the drop height, the greater the test result error. The sample test is prone to jumping due to impact, resulting in errors in the results. In addition, the production cycle of paint coating is long. SUMMARY

[0004] The purpose of the present application is to provide a virtual impact experiment method for paint coating of a suspended launching device, which solves the problem that the impact experiment results of the paint coating of the suspended launching device are affected by various environmental coupling factors such as temperature and humidity, so as to improve the confidence of the impact strength of the paint coating of the suspended launching device, shorten the experimental period, and improve the experimental efficiency.

[0005] The virtual impact experiment method for paint coating of a suspended launching device according to the present application is as follows:

[0006] S1, a virtual impact test platform for paint coating of a suspended launching device is constructed;

[0007] S2, the relationship between the pit depth x and the initial speed V of the punch is obtained by using the transient dynamics theory and finite element simulation;

[0008] S3, the equation of the pit depth x with respect to the initial speed V of the punch is fitted based on the Origin data processing platform;

[0009] S4, build a physical platform for impact test of paint coating of a suspended launching device, and obtain the pit depth x of the paint coating when the drop hammer falls from different heights H through a limited number of physical experiments;

[0010] S5, obtain the equation of pit depth x with respect to drop hammer height H based on the Origin data processing platform;

[0011] S6, obtain the analytical expression of the initial velocity v of the punch with respect to the drop hammer height H by simultaneously solving the equations;

[0012] S7, calculate the initial velocity of the punch under different height conditions, and use it as the load condition of the virtual impact test of the paint coating of the suspended launching device, and obtain the pit depth and residual stress under different height conditions;

[0013] S8, evaluate the strength of the paint film according to the criterion.

[0014] Advantageously, the virtual impact test digital model and the Lagrangian finite element model are established in S1.

[0015] Advantageously, the construction of the Lagrangian finite element numerical model mainly includes the construction of the material constitutive model, the construction of the link relationship, the mesh division and the element type, and the boundary conditions and load conditions.

[0016] Advantageously, S2 includes the following steps:

[0017] S2.1, calculate the maximum speed and minimum speed of the drop hammer at the maximum range Hmax and the minimum range Hmin respectively by the free fall formula, obtain the curve of the change of the punch speed with time by collision simulation, and determine the initial speed range of the punch;

[0018] S2.2, calculate the equivalent stress range and deformation range based on von Mises, i.e. the residual stress range and pit depth range of the paint coating.

[0019] Advantageously, a three-dimensional model and a numerical model of the drop hammer colliding with the punch are constructed in S2.1, and the numerical model includes the construction of the material constitutive model of the drop hammer and the punch, the construction of the grid model, the construction of the link relationship, the setting of the load conditions and the boundary conditions.

[0020] Advantageously, the equation of pit depth x with respect to the initial speed V of the punch obtained in S3 is:

[0021]

[0022] Advantageously, the equation of pit depth x with respect to drop hammer height H obtained in S5 is:

[0023]

[0024] Advantageously, the analytical expression of the punch initial velocity v with respect to the drop height H is:

[0025]

[0026] Advantageously, 50mm≤H≤800mm.

[0027] Advantageously, S8 is judged by GB / T 1732-2020 Impact Test Method for Paint Coatings.

[0028] Beneficial effects: through the virtual impact experiment of the suspension launching device, the impact strength of the coating can avoid the influence of environmental coupling such as temperature and humidity, improve the precision of the experimental results, avoid the production of the paint coating, significantly improve the experimental period and improve the experimental efficiency, avoid the problem that the measurement range of the existing experimental table is limited, and then the mechanical behavior under any working condition can be obtained, avoid the problem that the experimental result precision is low due to system error, measurement error and other factors in the physical experiment process, avoid the physical experiment, and therefore the experimental cost can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a virtual experiment overall flow chart of the paint coating impact strength of the suspension launching device.

[0030] Figure 2 It is a structural schematic diagram of the impact test platform.

[0031] Figure 3 It is a schematic diagram of the drop hammer and the punch in the impact strength experimental platform. DETAILED DESCRIPTION

[0032] The application will be further described in detail below with reference to the drawings.

[0033] The application takes the tinplate as a base body and polyurethane paint as a coating to specifically explain a virtual impact experiment method of the suspension launching device coating. The tinplate has a size of 150mm*50mm*0.28mm, and the coating has a size of 150mm*50mm*0.02mm.

[0034] Referring to Figure 1 , the method comprises the following steps:

[0035] S1, a virtual impact test platform of the paint coating of the suspension launching device is constructed.

[0036] Mainly including establishing a virtual impact experiment digital model and a Lagrange finite element model.

[0037] Referring to Figure 2 , the impact test platform comprises a heavy hammer 1, a punch 2, a die 3 and a base 4, and the base body coated with the paint coating is placed in the die 3.

[0038] The virtual impact experiment digital model is composed of a punch, a base, a base body and a paint coating, the base body is coated with the paint coating, the punch is located above the base body, and the base body is located above the base.

[0039] The construction of the Lagrange finite element numerical model mainly includes the construction of the material constitutive model, the construction of the link relationship, the mesh division and the element type, and the boundary condition and the load condition.

[0040] S2, the relationship between the pit depth x and the initial speed V of the punch is obtained by using the transient dynamics theory and finite element simulation.

[0041] The method mainly includes the following steps:

[0042] S2.1: the maximum and minimum falling hammer speeds at the maximum and minimum ranges Hmax and Hmin of the falling hammer are calculated respectively by using the free fall formula, a three-dimensional model and a numerical model of the falling hammer colliding with the punch are constructed, and see Figure 3 , the numerical model includes the construction of the falling hammer and the punch material constitutive model, the construction of the grid model, the construction of the link relationship, the setting of the load condition and the boundary condition. The maximum and minimum speeds of the falling hammer are set in the simulation platform, the change rule curve of the punch speed with time is obtained through the collision simulation, the maximum and minimum initial speeds of the punch are obtained according to the change rule curve, and the initial speed range of the punch is determined.

[0043] The falling hammer and the hammer head are both made of Q235 steel, and Johnson-Cook model is used; the grid adopts unstructured grid Solid186 and Solid187; the punch and the falling hammer adopt frictionless contact; the boundary condition is to release the Z direction constraint of the punch, and the other directions are zero displacement constraint. The maximum and minimum values of the initial speed of the punch are set as the load. The change rule curve of the punch speed with time is obtained through post-processing.

[0044] S2.2: according to the initial speed range of the punch, the equivalent stress range and the deformation range of the paint coating are calculated based on von Mises, that is, the residual stress range and the pit depth range of the paint coating.

[0045] S3, the equation of the pit depth x with respect to the initial speed V of the punch is obtained by fitting based on the Origin data processing platform:

[0046]

[0047] Step 4, build a paint coating impact experiment physical platform of the suspended launching device, and obtain the pit depth x of the paint coating when the falling hammer falls from different heights H through a limited number of physical experiments. The method mainly includes the following steps:

[0048] Step 4.1: make the paint coating on the base body;

[0049] Step 4.2: Place the substrate on the test bench, adjust the ruler, and set different drop hammer heights;

[0050] Step 4.3: Press the button to make the drop hammer free fall;

[0051] Step 4.4: Measure the crater depth by using a vernier caliper.

[0052] Step 5: Based on the Origin data processing platform, the equation of the crater depth x with respect to the drop hammer height H is fitted as:

[0053]

[0054] Step 6: The analytical expression of the punch initial speed v with respect to the drop hammer height H is obtained by solving the equations simultaneously:

[0055]

[0056] Step 7: The punch initial speed under different height conditions is obtained through the analytical expression of the punch initial speed v with respect to the drop hammer height H, and this is used as the load condition of the virtual impact test of the paint coating of the suspended launching device. The crater depth and residual stress under different height conditions are obtained through the virtual impact test.

[0057] Step 8: According to the criterion of "GB / T1732-2020 Impact Test Method for Paint Coating", the strength of the paint coating is evaluated.

[0058] As analyzed above, the present application solves the problem that the impact test results of the paint coating of the suspended launching device are affected by various environmental coupling factors such as temperature and humidity, improves the confidence of the impact strength of the paint coating of the suspended launching device, shortens the experimental period, improves the efficiency of the experiment, and reduces the experimental cost.

[0059] Those skilled in the art will readily understand that the above description is only a preferred example of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A virtual impact test method for paint coating of a suspended launching device, characterized in that, The method comprises the following steps: S1, a virtual impact test platform for paint coating of a suspended launching device is constructed; A virtual impact experiment digital model and a Lagrange finite element model are established, and the construction of the Lagrange finite element numerical model mainly includes construction of a material constitutive model, construction of a linkage relationship, mesh division and element type, and boundary conditions and load conditions; S2, the relationship of pit depth x with the initial speed V of the punch is obtained by using transient dynamics theory and finite element simulation; S3, the equation of pit depth x with the initial speed V of the punch is fitted based on an Origin data processing platform, and is as follows: ； S4, a paint coating impact experiment physical platform for the suspended launching device is built, and the pit depth x of the paint coating when the drop hammer falls from different heights H is obtained through a limited number of physical experiments; S5, the equation of pit depth x with the drop hammer height H is fitted based on an Origin data processing platform, and is as follows: S6, the analytical expression of the initial speed v of the punch with the drop hammer height H is obtained by simultaneously solving the equations, and is as follows: ； S7, the initial speed of the punch under different height conditions is calculated, and this is used as the load condition of the virtual impact experiment of the paint coating of the suspended launching device, so as to obtain the pit depth and residual stress under different height conditions; S8, the strength of the paint film is evaluated according to the criterion.

2. The method of claim 1, wherein: S2 comprises the following steps: S2.1, the maximum speed and the minimum speed of the drop hammer at the maximum range Hmax and the minimum range Hmin are respectively calculated through a free fall formula, the change rule curve of the speed of the punch with time is obtained through collision simulation, and the initial speed range of the punch is determined; S2.2, the equivalent stress range and the deformation range are calculated based on von Mises, that is, the residual stress range and the pit depth range of the paint coating.

3. The method of claim 2, wherein: In S2.1, a three-dimensional model and a numerical model of the collision of the drop hammer and the punch are constructed, and the numerical model includes construction of a material constitutive model of the drop hammer and the punch, construction of a mesh model, construction of a linkage relationship, setting of load conditions and boundary conditions.

4. The method of claim 3, wherein: 。 5. The method of claim 1, wherein: In S8, GB / T1732-2020 Impact Test Method for Paint Coating is used as the criterion.

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