A Laser Cleaning Simulation Method Based on Multi-Field Coupling of Light-Thermal-Flow

Abstract

The present invention proposes a laser cleaning simulation method based on the multi-field coupling of light-thermal-flow. The method includes the following steps: Step 1: Light field modeling; Step 2: Thermal field modeling; Step 3: Flow field modeling; Step 4: Introduce a weight coefficient to establish a multi-physical field coupling model of the light field, thermal field and flow field; Step 5: Conduct laser cleaning simulation research. The method takes into account that during the laser cleaning process, different physical states will cause inconsistent weight coefficients of different physical fields, and the model established by considering the weight coefficient in the laser cleaning model will more accurately reflect the actual process of the material to be cleaned by laser cleaning, solving the problem that the weight coefficient has been simplified and ignored in the previous research in the constructed multi-field coupling model.

Description

Technical Field

[0001] The present invention relates to the technical field of laser cleaning, and particularly to a laser cleaning simulation method based on multi-field coupling of light-thermal-flow. Background Art

[0002] Green manufacturing has become one of the five major projects for the future development and construction of China, and it is a modern manufacturing mode with ecological environment and resource benefits as the core consideration factors. Laser cleaning technology is known as the "most potential green cleaning technology in the 21st century". Laser cleaning technology refers to a process in which an externally applied laser beam acts on the surface of the contaminants to be cleaned, and the contaminants are removed and collected through complex physical and chemical reactions between the laser and the contaminants.

[0003] Currently, the mechanism research of laser cleaning globally is still in the exploratory stage, and the mechanism of laser cleaning under the multi-field coupling of light-thermal-flow is still unclear. Therefore, giving a simulation scheme under the multi-field coupling of light-thermal-flow and obtaining the action mechanism between the laser and the material to be cleaned are urgent problems to be solved.

[0004] In previous studies, only the simulation analysis of laser cleaning of the material to be cleaned under the action of the light field, thermal field, and flow field was considered separately. This research method cannot truly reflect the action characteristics between the laser and the material to be cleaned. Previous studies ignored the coupling relationship between the light-thermal-flow fields and did not consider the mutual influence between the light-thermal-flow fields, making it difficult to obtain a true simulation of laser cleaning.

[0005] In addition, in the constructed multi-field coupling model, the weight coefficients were simplified and ignored in previous studies, and the weight coefficients in different physical fields are particularly important. In previous studies, the considered models and factors were not comprehensive, and it was impossible to truly reflect the action state between the laser and the material to be cleaned, making it difficult to accurately obtain the parameters and morphology during and after the laser cleaning process. Therefore, how to efficiently and accurately obtain the laser cleaning simulation is an important problem that needs to be solved urgently. Summary of the Invention

[0006] The object of the present invention is to address the problems of "only considering the simulation analysis of laser cleaning of the material to be cleaned under the action of the light field, thermal field, and flow field separately" and "in the constructed multi-field coupling model, the weight coefficients were simplified and ignored in previous studies" existing in the prior art, and a laser cleaning simulation method based on multi-field coupling of light-thermal-flow is proposed.

[0007] The present invention is realized through the following technical solutions. The present invention proposes a laser cleaning simulation method based on multi-field coupling of light-thermal-flow, and the method includes the following steps:

[0008] Step 1: Light field modeling: Construct an energy coupling model and establish a transient optical model of the substrate surface;

[0009] Step 2: Thermal field modeling: Construct a heat conduction and heat flow model, establish a laser model with a Gaussian distribution, and use the Green's function for solution to obtain the surface temperature;

[0010] Step 3: Flow field modeling: Construct a flow field model and determine the flow field boundary conditions based on the particle flow and plasma expansion;

[0011] Step 4: Introduce weight coefficients and establish a multi-physics coupling model of the optical field, thermal field, and flow field: Introduce weight coefficients G(J), R(J), and L(J) to establish a multi-physics coupling model of the optical field, thermal field, and flow field;

[0012] Step 5: Conduct laser cleaning simulation research.

[0013] Furthermore, in Step 1, during the laser cleaning process, the optical field acts on the substrate surface, and through inverse bremsstrahlung absorption, the free electrons on the metal surface are excited. The energy coupling model is:

[0014]

[0015]

[0016] where C e and C l are the electron heat capacity and lattice heat capacity; T e and T l are the electron temperature and lattice temperature respectively; k e is the electron thermal conductivity, g is the electron-phonon coupling coefficient, and I eff is the laser heat source term.

[0017] Furthermore, in Step 1, according to the Drude classical free electron gas theory, construct a transient optical model, and the dielectric function equation is expressed as:

[0018]

[0019]

[0020] In the formula, ε1 is the real part of the dielectric function; ε2 is the imaginary part of the dielectric function; ρ e is the free electron density, is the laser frequency, m e is the electron mass, ε0 is the vacuum permittivity, and τ e is the electron relaxation time;

[0021] The complex refractive index of the free electron gas is expressed as:

[0022]

[0023] Among them, is the normal refractive index, is the extinction coefficient, and the expression is:

[0024]

[0025]

[0026] The reflectivity R and absorption coefficient α during the laser cleaning process are expressed as:

[0027]

[0028]

[0029] Furthermore, in step 2, during the laser cleaning process, the heat flux of heat conduction is on the plane and is proportional to the local temperature gradient, and the expression is:

[0030] Φ(z) = -k(dT / dz)

[0031] where k is the thermal conductivity of the material and z is the thickness; the heat flux equation is expressed as:

[0032]

[0033] where Cp is the specific heat; the laser satisfies the Gaussian distribution, and the expression is:

[0034] q(x,y) = 2(1 - R)I / πr 2 *exp(-2(x 2 + y 2 ) / r 2 )

[0035] In the formula, q is the energy density of the laser, I is the peak energy of the incident laser, R is the reflectivity, and r is the beam spot radius.

[0036] Furthermore, in step 2, the thermal diffusivity K d is expressed as:

[0037] K d = k / p*Cp

[0038] Assuming that the thermal and optical parameters are invariant with temperature, the analytical solution is obtained using the Green's function, and the expression is:

[0039] T(z,t) = 2(1 - R)I / πr 2 *(K d t / k)*(ierfc(z / kt) - ierfc(z 2 + r 2 / kt))

[0040] where ierfc is the complementary error function, and the expression is:

[0041]

[0042] Under the action of a single laser pulse, the temperature on the surface of the irradiated target is:

[0043] T(0,t) = 2(1 - R)P / k * (K d t / π).

[0044] Furthermore, in step 3, if the temperature of the laser cleaning is too high, the substrate material will melt and form a flow field. Therefore, the flow field modeling of laser cleaning is carried out, and the expression is:

[0045]

[0046] where c l , ρ l , k l are the heat capacity, mass density, and thermal conductivity of the liquid respectively, n x is the density of excited particles, H is the vapor height, and σ PI is the photoionization cross-section;

[0047] According to the Hertz-Knudsen equation, the surface evaporation rate is expressed as

[0048]

[0049] where p is the vapor surface pressure, ρ is the substance density, m is the average mass of the particles, and k b is the Boltzmann constant, and T(0,t) is the surface temperature;

[0050] According to the Clapeyron equation, the vapor surface pressure is expressed as:

[0051]

[0052] In the formula, p b is 1 atm, L is the latent heat of the target material, and T b is the boiling temperature at pressure p b ;

[0053] The density of excited particles n x is expressed as:

[0054] n x (T p ) = n0 exp(-ε / k b T p )

[0055] Wherein, n0 is the total particle density, ε is the energy from the ground state to the first excited state, and Tp is the plasma temperature.

[0056] Further, in Step 3, during the laser cleaning process, when the plasma expands outward, the plasma length changes with time, and the kinetic equation of plasma expansion is expressed as:

[0057]

[0058] Where dX / dt and dY / dt are the expansion velocities of the plasma edges X and Y, respectively;

[0059] The velocity v of the hot particles is expressed as:

[0060]

[0061] Based on the law of conservation of energy, the flow field boundary condition is expressed as:

[0062]

[0063] Further, in Step 4, the multi-physical field coupling model is:

[0064]

[0065] Wherein, G(J), R(J), and L(J) are the weight coefficients of the optical field, thermal field, and flow field, respectively.

[0066] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the laser cleaning simulation method based on optical-thermal-flow multi-field coupling are implemented.

[0067] The present invention also provides a computer-readable storage medium for storing computer instructions, and when the computer instructions are executed by a processor, the steps of the laser cleaning simulation method based on optical-thermal-flow multi-field coupling are implemented.

[0068] Advantages of the present invention:

[0069] The present invention proposes a laser cleaning simulation method based on the multi-field coupling of light, heat, and fluid flow. The method considers the simulation analysis of laser cleaning the material to be cleaned under the coupling action of the light field, heat field, and fluid flow field. In the COMSOL Multiphysics simulation, it truly reflects the action characteristics of the laser and the material to be cleaned, and realizes obtaining parameters and topography during and after the laser cleaning process. Secondly, the method takes into account that during the laser cleaning process, different physical states will cause inconsistent weight coefficients of different physical fields. The model established by considering the weight coefficients in the laser cleaning model will more accurately reflect the actual process of laser cleaning the material to be cleaned, and solves the problem that the weight coefficients are simplified and ignored in the previously constructed multi-field coupling model. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0071] Figure 1 It is a flow chart of a laser cleaning simulation method based on the multi-field coupling of light, heat, and fluid flow according to the present invention.

[0072] Figure 2 It is a mesh division diagram of a three-dimensional geometric model.

[0073] Figure 3 It is a topography diagram of cross-sections at different times under a laser energy density of 3 J / cm 2 ².

[0074] Figure 4 It is a diagram of the highest surface temperature and topography under a laser energy density of 3 J / cm 2 ².

[0075] Figure 5 It is a diagram of the highest surface temperature and topography under a laser energy density of 9 J / cm 2 ².

[0076] Figure 6 It is a diagram of the highest surface temperature and topography under a laser energy density of 15 J / cm 2 ².

[0077] Figure 7 It is a diagram of the highest surface temperature and topography under a laser energy density of 19 J / cm 2 ². DETAILED DESCRIPTION OF THE EMBODIMENTS

[0078] 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. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. 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.

[0079] Combined with Figures 1-7 , the present invention proposes a laser cleaning simulation method based on multi-field coupling of light-thermal-flow. The method includes the following steps:

[0080] Step 1: Optical field modeling: Construct an energy coupling model and establish a transient optical model on the substrate surface;

[0081] Step 2: Thermal field modeling: Construct a heat conduction and heat flow model, establish a Gaussian distribution laser model, and use the Green's function to solve to obtain the surface temperature;

[0082] Step 3: Flow field modeling: Construct a flow field model and determine the flow field boundary conditions according to the particle flow and plasma expansion;

[0083] Step 4: Introduce weight coefficients and establish a multi-physics field coupling model of the optical field, thermal field, and flow field: Introduce weight coefficients G(J), R(J), and L(J) to establish a multi-physics field coupling model of the optical field, thermal field, and flow field;

[0084] Step 5: Conduct laser cleaning simulation research.

[0085] In step 1, during the laser cleaning process, the optical field acts on the substrate surface, and through inverse bremsstrahlung absorption, free electrons on the metal surface are excited. The energy coupling model is:

[0086]

[0087]

[0088] Among them, C e and C l are the electron heat capacity and lattice heat capacity; T e and T l are the electron temperature and lattice temperature respectively; k e is the electron thermal conductivity, g is the electron-phonon coupling coefficient, and I eff is the laser heat source term.

[0089] In step 1, according to the Drude classical free electron gas theory, a transient optical model is constructed, and the dielectric function equation is expressed as:

[0090]

[0091]

[0092] where ε1 is the real part of the dielectric function; ε2 is the imaginary part of the dielectric function; ρ e is the free electron density, is the laser frequency, m e is the electron mass, ε0 is the vacuum permittivity, τ e is the electron relaxation time;

[0093] The complex refractive index of the free electron gas is expressed as:

[0094]

[0095] where, is the normal refractive index, is the extinction coefficient, and the expression is:

[0096]

[0097]

[0098] The reflectivity R and absorption coefficient α during the laser cleaning process are expressed as:

[0099]

[0100]

[0101] In step 2, during the laser cleaning process, the heat flux of heat conduction is on the plane and is proportional to the local temperature gradient, and the expression is:

[0102] Φ(z) = -k(dT / dz)

[0103] where k is the thermal conductivity of the material, z is the thickness; the heat flow equation is expressed as:

[0104]

[0105] where Cp is the specific heat; the laser satisfies the Gaussian distribution, and the expression is:

[0106] q(x,y) = 2(1 - R)I / πr 2 *exp(-2(x 2 +y 2 ) / r 2 )

[0107] In the formula, q is the energy density of the laser, I is the peak energy of the incident laser, R is the reflectivity, and r is the beam spot radius.

[0108] In step 2, the thermal diffusivity K d is expressed as:

[0109] K d = k / p * Cp

[0110] Assume that the thermal and optical parameters are invariant with temperature, and the analytical solution is obtained using the Green's function. The expression is:

[0111] T(z, t) = 2(1 - R)I / πr 2 *(K d t / k)*(ierfc(z / √kt) - ierfc(z 2 + r 2 / √kt))

[0112] where ierfc is the complementary error function, and the expression is:

[0113]

[0114] Under the action of a single laser pulse, the temperature of the irradiated target surface is:

[0115] T(0, t) = 2(1 - R)P / k * (K d t / π).

[0116] In step 3, if the temperature of laser cleaning is too high, the substrate material will melt and form a flow field. Thus, the flow field modeling of laser cleaning is carried out. The expression is:

[0117]

[0118] where, c l , ρ l , k l are the specific heat capacity, mass density, and thermal conductivity of the liquid respectively, n x is the density of excited particles, H is the vapor height, σ PI is the photoionization cross-section, usually taken as 1.3×10 -17 cm 2 ;

[0119] According to the Hertz-Knudsen equation, the surface evaporation rate is expressed as

[0120]

[0121] where, p is the vapor surface pressure, ρ is the substance density, m is the average mass of particles, k b is the Boltzmann constant, and T(0, t) is the surface temperature;

[0122] According to the Clapeyron equation, the vapor surface pressure is expressed as:

[0123]

[0124] where p b is 1 atm, L is the latent heat of the target material, and T b is the boiling temperature at pressure p b ;

[0125] The density n of excited particles x is expressed as:

[0126] n x (T p ) = n0 exp(-ε / k b T p )

[0127] where n0 is the total particle density, ε is the energy from the ground state to the first excited state, and Tp is the plasma temperature.

[0128] In step 3, during the laser cleaning process, when the plasma expands outward, the plasma length changes with time, and the kinetic equation for plasma expansion is expressed as:

[0129]

[0130] where dX / dt and dY / dt are the expansion velocities of the plasma edges X and Y, respectively;

[0131] The velocity v of hot particles is expressed as:

[0132]

[0133] Based on the law of conservation of energy, the flow field boundary conditions are expressed as:

[0134]

[0135] In step 4, the multi-physics coupling model is:

[0136]

[0137] where G(J), R(J), and L(J) are the weight coefficients of the optical field, thermal field, and flow field, respectively.

[0138] In step 5, the multi-physics coupling model is simulated in COMSOL Multiphysics to obtain the interaction characteristics between the laser and the material to be cleaned, and thus the parameters and morphology during and after the laser cleaning process can be obtained. For details, see Figure 4 , Figure 5 , Figure 6 and Figure 7 , Figure 4 which are the surface maximum temperature map and morphology at a laser energy density of 3 J / cm 2 .Figure 5 At a laser energy density of 9 J / cm 2 the surface maximum temperature map and topography. Figure 6 At a laser energy density of 15 J / cm 2 the surface maximum temperature map and topography. Figure 7 At a laser energy density of 19 J / cm 2 the surface maximum temperature map and topography.

[0139] The present invention also provides an electronic device, including a memory and a processor, where the memory stores a computer program, and when the processor executes the computer program, the steps of the laser cleaning simulation method based on the multi-field coupling of light-thermal-fluid are implemented.

[0140] The present invention also provides a computer-readable storage medium for storing computer instructions, and when the computer instructions are executed by a processor, the steps of the laser cleaning simulation method based on the multi-field coupling of light-thermal-fluid are implemented.

[0141] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct rambus random access memory (DRRAM). It should be noted that the memory of the method described in the present invention is intended to include but not limited to these and any other suitable types of memory.

[0142] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from a website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wirelessly (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that the computer can access or a data storage device such as a server or data center that includes one or more integrated available media. The available medium can be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a high-definition digital video disc (DVD)), or a semiconductor medium (such as a solid state disc (SSD)), etc.

[0143] In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in the processor or the instructions in the form of software. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as being executed and completed by the hardware processor, or executed and completed by the combination of the hardware and software modules in the processor. The software module can be located in a mature storage medium in the art such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, register, etc. This storage medium is located in the memory, and the processor reads the information in the memory and combines its hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

[0144] It should be noted that the processor in the embodiments of the present application can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiments can be completed by the integrated logic circuit in the hardware of the processor or instructions in the form of software. The above-mentioned processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as being executed and completed by a hardware decoding processor, or executed and completed by a combination of hardware and software modules in the decoding processor. The software module can be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory, and the processor reads the information in the memory and combines its hardware to complete the steps of the above method.

[0145] The above has introduced in detail a laser cleaning simulation method based on multi-field coupling of light-thermal-flow proposed by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A laser cleaning simulation method based on light-heat-fluid multi-field coupling, characterized in that: The method comprises the following steps: Step 1: Light field modeling: construct an energy coupling model and establish a transient optical model of the substrate surface; Step 2: Thermal field modeling: construct heat conduction and heat flow models, establish a Gaussian distribution laser model, and use Green's function to solve and obtain the surface temperature; Step 3: Flow field modeling: Construct a flow field model and determine the flow field boundary conditions based on particle flow and plasma expansion; Step 4: Introduce weight coefficients to establish a multi-physics coupling model of light field, thermal field and flow field: Introduce weight coefficients G(J), R(J) and L(J) to establish a multi-physics coupling model of light field, thermal field and flow field; Step 5: Conduct laser cleaning simulation research; In step 3, the temperature of laser cleaning is too high, the substrate material will melt, and a flow field will be formed. Therefore, the laser cleaning flow field modeling is carried out, and the expression is: Among them, c l , ρ l ,k l are heat capacity, mass density and thermal conductivity of the liquid, n x is the excited particle density, H is the vapor height, σ PI is the photoionization cross section; According to the Hertz-Knudsen equation, the rate of surface evaporation is expressed as Where p is the vapor surface pressure, ρ is the material density, m is the average mass of the particles, and k b is the Boltzmann constant, T(0,t) is the surface temperature; According to the Clapeyron equation, the steam surface pressure is expressed as: Where p b is 1atm, L is the latent heat of the target material, T b is the pressure p b Boiling temperature below Excited particle density n x It is expressed as: n x (T p )=n0 exp(-ε b / k b / T p ) Where n0 is the total particle density, ε b is the energy from the ground state to the first excited state, Tp is the plasma temperature; In step 3, during the laser cleaning process, as the plasma expands outward, the plasma length changes with time, and the kinetic equation for plasma expansion is expressed as: Where dX / dt and dY / dt are the expansion speeds of the plasma edges X and Y, respectively; The thermal particle velocity v is expressed as: Based on the law of conservation of energy, the flow field boundary conditions are expressed as: In step 4, the multiphysics coupling model is: Among them, G(J), R(J) and L(J) are the weight coefficients of light field, thermal field and flow field respectively; C e is the electron heat capacity, T e is the electron temperature, R is the reflectivity, u(t) represents the evaporation rate, k is the thermal conductivity of the material, K d Expressed as thermal diffusivity.

2. The method according to claim 1, characterized in that: In step 1, during the laser cleaning process, the light field acts on the substrate surface and excites the free electrons on the metal surface through inverse bremsstrahlung absorption. The energy coupling model is: Among them, C e and C l are the electron heat capacity and lattice heat capacity; T e and T l are the electron temperature and lattice temperature respectively; k e is the electronic thermal conductivity, g is the electron-phonon coupling coefficient, I eff is the laser heat source term.

3. The method according to claim 2, characterized in that In step 1, a transient optical model is constructed according to Drude's classical free electron gas theory, and the dielectric function equation is expressed as: Where ε1 is the real part of the dielectric function; ε2 is the imaginary part of the dielectric function; ρ e is the free electron density, is the laser frequency, m e is the electron mass, ε0 is the vacuum dielectric constant, τ e is the electron relaxation time; The complex refractive index of a free electron gas is expressed as: in, is the normal refractive index, is the extinction coefficient, and its expression is: The reflectivity R and absorption coefficient α during laser cleaning are expressed as:

4. The method according to claim 3, characterized in that: In step 2, during the laser cleaning process, the heat flux of heat conduction is on the plane and is proportional to the local temperature gradient, expressed as: Φ(z)=-k(dT / dz) Where k is the thermal conductivity of the material and z is the thickness; the heat flow equation is expressed as: Where Cp is the specific heat; the laser satisfies the Gaussian distribution, and the expression is: q(x,y)=2(1-R)I / πr 2 *exp(-2(x 2 +y 2 ) / r 2 ) Where q is the energy density of the laser, I is the peak energy of the incident laser, R is the reflectivity, and r is the beam spot radius.

5. The method according to claim 4, characterized in that In step 2, the thermal diffusion coefficient K d It is expressed as: K d =k / p*Cp Assuming that the thermal and optical parameters remain constant with temperature, the analytical solution is obtained using the Green's function, which is expressed as: T(z,t)=2(1-R)I / πr 2 *(K d t / k)*(ierfc(z / kt)-ierfc(z 2 +r 2 / kt)) Where ierfc is the complementary error function, expressed as: Under the action of a single laser pulse, the temperature of the irradiated target surface is: T(0,t)=2(1-R)P / k*(K d t / π)。 6. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

7. A computer-readable storage medium for storing computer instructions, characterized in that: When the computer instructions are executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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