Laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback

Abstract

The invention discloses a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback, and relates to the technical field of laser cladding, and the method comprises the following steps: constructing a laser cladding single-channel three-dimensional numerical simulation model, and endowing thermophysical parameters of a nonlinear material to the laser cladding single-channel three-dimensional numerical simulation model; adding a physical field and coupling to set boundary conditions; carrying out grid division on the established model and establishing a transient research step; and carrying out a laser cladding experiment to process a transient simulation result. According to the method, the laser cladding molten pool morphology prediction model is established, the dynamic behavior process of the molten pool is accurately simulated, prediction errors are effectively reduced, high-precision prediction of the laser cladding molten pool morphology is achieved, and reliable data support is provided for actual production. And laser cladding process parameters such as laser power, scanning speed and powder feeding rate are adjusted in real time according to a prediction result, so that the morphology of a molten pool is optimized, and the coating quality is improved. Therefore, the subsequent processing links are reduced, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of laser cladding, and in particular to a method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback. Background Art

[0002] Laser cladding (LC) technology boasts high energy density, low pollution, a small heat-affected zone, and high bonding strength. It is also unrestricted by part shape and can be used to repair and reinforce complex critical parts. It is widely used in mold repair, additive manufacturing, surface modification, and the aerospace industry. Specifically, this technology uses a high-energy laser beam to melt the cladding material and rapidly solidify it on the substrate surface, forming a coating with specialized properties. The coating's geometric morphology plays a critical role in its performance and functional applications. In industrial applications, melt pool size is a key parameter for evaluating LC process control and quality. Melt pool morphology is influenced by multiple factors, including LC processing conditions (such as laser power, scanning speed, and powder feed rate), material properties (such as melting point and density differences), and the interaction between the substrate and cladding material. Precise control of these parameters allows optimization of the cladding layer's geometric characteristics, thereby improving both its performance and the overall quality of the part.

[0003] LC is a dynamic, rapid solidification process with significant uncertainty, and cooling rates can reach 105K / s. Some unstable physical dynamics are not strictly coupled to specific processing conditions. This instability introduces significant uncertainty into the identification and certification of LC melt pool morphology, making melt pool morphology prediction more complex. However, conventional laser cladding processes rely primarily on experienced operators to adjust parameters, making precise control difficult. Computer-based numerical simulations are expected to address this challenge, and their significant advantages in macroscopic morphology prediction have attracted significant interest from many scholars. However, there are two main limitations: first, the predefined melt pool shape limits the model's predictive power and applicability; second, the influence of the free motion of the melt pool surface on the melt pool morphology is not considered, making it difficult to achieve accurate predictions of the melt pool morphology using the model. Summary of the Invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by the present invention is that the existing laser cladding process is difficult to achieve precise control, the predefined molten pool shape limits the predictive ability and applicability of the model, and does not consider the influence of the free movement of the molten pool surface on the molten pool morphology, making it difficult to achieve accurate prediction of the molten pool morphology by the model.

[0006] To solve the above technical problems, the present invention provides the following technical solutions: a method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback, comprising constructing a three-dimensional numerical simulation model of a single-pass laser cladding, assigning thermophysical parameters of nonlinear materials to the three-dimensional numerical simulation model of the single-pass laser cladding; adding physical fields and coupling to set boundary conditions; meshing the established model and establishing a transient research step; conducting laser cladding experiments and correcting the transient simulation results.

[0007] As a preferred solution of the laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback described in the present invention, wherein: the said constructing a three-dimensional numerical simulation model of a single-pass laser cladding and assigning thermal physical parameters of nonlinear materials to the three-dimensional numerical simulation model of a single-pass laser cladding includes establishing a three-dimensional numerical simulation model of a single-pass laser cladding, adopting symmetric boundary conditions, and setting the size of the substrate.

[0008] As a preferred embodiment of the method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback described in the present invention, the method comprises: constructing a three-dimensional numerical simulation model of a single-pass laser cladding, and assigning thermophysical parameters of a nonlinear material to the three-dimensional numerical simulation model of the single-pass laser cladding, comprising assigning thermophysical parameters of the nonlinear material, and calculating the specific heat capacity, thermal conductivity, surface tension, and density of the cladding powder and the substrate based on JMatPro commercial software;

[0009] Based on the characteristics of the material's solid-liquid transition, the material's liquidus temperature is obtained as a basis for material assignment and obtaining the simulated molten pool size;

[0010] Based on the thermophysical parameters of the matrix and powder, they are assigned to the model and expressed as:

[0011]

[0012] Among them, φ represents the material thermal property judgment parameter, T, T m 、T l and T s Denote the temperature variable, melting point, liquidus temperature, and solidus temperature, respectively. S(x) denotes a smooth step function. z, z0, and Δz denote the vertical displacement variable, the initial surface level, and the size of the transition zone in the z direction, respectively.

[0013] As a preferred solution of the laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback described in the present invention, the physical field addition and coupled setting of boundary conditions include the introduction of laminar flow, fluid heat transfer and deformation geometry physical fields based on the multi-physical processes of melt flow, heat transfer and cladding layer protrusion involved in the laser cladding molten pool process;

[0014] The Laminar Flow interface and the Fluid Heat Transfer interface are coupled to form the non-isothermal flow and Marangoni convection physics fields;

[0015] Deformation geometry is used to simulate the process of powder injection, melting, and solidification to form a coating;

[0016] The influence on the geometry of the molten pool is the laser input energy Q and the movement speed V of the solid-liquid interface caused by powder filling. p , expressed as:

[0017]

[0018] Where t represents time, α represents laser absorption rate, P represents laser power, rs represents laser spot radius, v represents scanning speed, (x, y) represents the coordinates of the center of the spot, (x0, y0) represents the coordinates of the initial laser beam position, m f represents the mass flow rate, η m Powder utilization rate, ρ m represents the powder density, r p represents the mass flow radius, z represents the unit vector parallel to the laser direction;

[0019] Introduce correction factors a and b to correct Q and V p , that is, Q′=a×Q and Vp′=b×Vp.

[0020] As a preferred solution of the laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback described in the present invention, wherein: the step of meshing the established model and establishing a transient study includes performing regional meshing based on reliability and rationality;

[0021] Create a transient study step, study the time and step size, and use the transient study step;

[0022] Transient solvers include absolute tolerance, time stepping, maximum number of iterations, PARDISO solver, and error.

[0023] As a preferred embodiment of the method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback described in the present invention, the method comprises: conducting a laser cladding experiment to process transient simulation results, performing a laser cladding experiment, selecting a laser parameter combination, capturing the morphological changes of the molten pool by a high-speed camera, and analyzing the shape, size, and dynamic behavior of the molten pool;

[0024] The transient simulation results were post-processed using COMSOL software, and the three-dimensional morphology of the molten pool was obtained based on the liquidus temperature of the material.

[0025] As a preferred embodiment of the method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback described in the present invention, the laser cladding experiment processing transient simulation results includes using Image Pro software to compare and analyze the sizes of the experimental molten pool monitoring and the numerical simulation molten pool to determine whether the error is within 10%;

[0026] After introducing the boundary condition correction factor, the dynamic diagram of the numerical simulation melt pool is obtained.

[0027] Another object of the present invention is to provide a laser cladding molten pool morphology prediction system based on numerical simulation and monitoring feedback, which can solve the problem of difficulty in achieving precise control in the current laser cladding process by establishing a three-dimensional numerical simulation model of a single laser cladding pass.

[0028] As a preferred solution of the laser cladding molten pool morphology prediction system based on numerical simulation and monitoring feedback described in the present invention, it includes: a laser cladding single-pass three-dimensional numerical simulation model construction module, a thermophysical property parameter assignment module, and a correction factor introduction module; the laser cladding single-pass three-dimensional numerical simulation model construction module is used to establish a multi-physical field coupling numerical model involving melt flow, heat transfer and cladding layer protrusion; the thermophysical property parameter assignment module is used to capture the dynamic process of the laser cladding molten pool in real time based on the molten pool monitoring system; the correction factor introduction module is used to introduce boundary condition correction factors based on real-time monitoring feedback of the molten pool.

[0029] A computer device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback.

[0030] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback.

[0031] Beneficial effects of the present invention: The laser cladding melt pool morphology prediction method based on numerical simulation and monitoring feedback provided by the present invention establishes a laser cladding melt pool morphology prediction model. By combining numerical simulation with real-time monitoring and feedback technology, the method effectively reduces prediction errors by accurately simulating the dynamic behavior of the melt pool, achieving high-precision prediction of laser cladding melt pool morphology and providing reliable data support for actual production. Furthermore, the present invention can adjust laser cladding process parameters such as laser power, scanning speed, and powder feed rate in real time based on the prediction results, thereby optimizing the melt pool morphology and improving coating quality. This helps to reduce subsequent processing steps and lower production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 An overall flow chart of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback provided in the first embodiment of the present invention.

[0034] Figure 2 A numerical simulation geometric model and mesh division schematic diagram of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback is provided in the first embodiment of the present invention.

[0035] Figure 3 A thermophysical parameter diagram of a substrate and cladding powder in a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback is provided in the first embodiment of the present invention.

[0036] Figure 4 A laser cladding molten pool monitoring dynamic diagram of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback is provided in the first embodiment of the present invention.

[0037] Figure 5 The first embodiment of the present invention provides a three-dimensional temperature field result and a schematic diagram of the obtained molten pool morphology of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback.

[0038] Figure 6 The first embodiment of the present invention provides a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback and a numerical simulation molten pool development dynamic diagram consistent with the molten pool monitoring parameters.

[0039] Figure 7 A size comparison diagram of a numerical model (before correction) and molten pool monitoring of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback provided in a second embodiment of the present invention.

[0040] Figure 8 A dynamic diagram of molten pool development after correction of a numerical simulation model of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback provided in a second embodiment of the present invention.

[0041] Figure 9 A size comparison diagram of a numerical model (after correction) and molten pool monitoring of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback provided in a second embodiment of the present invention.

[0042] Figure 10 A numerical model (verification) of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback is provided as a second embodiment of the present invention, showing a dynamic diagram of molten pool development.

[0043] Figure 11 A second embodiment of the present invention provides a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback and a molten pool monitoring diagram consistent with the process parameters of the numerical model (verification).

[0044] Figure 12 A size comparison diagram of a numerical model (verification) and molten pool monitoring of a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback provided in the second embodiment of the present invention. DETAILED DESCRIPTION

[0045] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0046] Example 1, reference Figures 1-10 , which is an embodiment of the present invention, provides a method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback, comprising:

[0047] S1: Construct a three-dimensional numerical simulation model of a single laser cladding pass and assign the thermal physical properties of nonlinear materials to the three-dimensional numerical simulation model of a single laser cladding pass.

[0048] Furthermore, Figure 2 A three-dimensional numerical simulation model of a single laser cladding pass was established. To reduce the computational time, symmetric boundary conditions were used to improve computational efficiency (only half of the model was calculated). The dimensions of the substrate were length × width × height = 15 mm × 5 mm × 4 mm.

[0049] It should be noted that if Figure 3 , the thermal physical parameters of nonlinear materials are assigned. Among them, the cladding powder (Fe 50 Mn 30 Co 10 Cr 10 The specific heat capacity, thermal conductivity, surface tension, and density of the high-entropy alloy (HEA) and the matrix (17-4Ph stainless steel) were determined. Furthermore, the liquidus temperature of the material was determined based on the solid-liquid transition characteristics of the material, which served as the basis for material assignment and the size of the simulated melt pool.

[0050] Based on the thermophysical parameters of the matrix and powder, they are assigned to the model using the following function:

[0051]

[0052] Where φ represents the material thermophysical property parameter, T, Tm, Tl, and Ts represent the temperature variable, melting point, liquidus temperature, and solidus temperature, respectively. S(x) represents a smooth step function to avoid numerically unfavorable sharp steps. z, z0, and Δz represent the vertical displacement variable, the initial surface level, and the size of the transition zone in the z direction, respectively.

[0053] S2: Add physical fields and couple to set boundary conditions.

[0054] Furthermore, physical fields are added and coupled, and boundary conditions are set. This model is based on the multi-physical processes of melt flow, heat transfer, and cladding layer protrusion involved in the laser cladding molten pool process, and introduces laminar flow, fluid heat transfer, and deformation geometry physics fields respectively. Among them, the laminar flow interface and the fluid heat transfer interface are coupled to form non-isothermal flow and Marangoni convection physics fields. Deformation geometry is used to simulate the process of continuous powder injection, melting, and solidification to finally form a coating. The main factors that have a significant impact on the geometry of the molten pool are the laser input energy (Q) and the movement speed of the solid-liquid interface caused by powder filling (Vp), which can be expressed as:

[0055]

[0056] Where, t represents time, α represents laser absorption rate, P represents laser power, rs represents laser spot radius, v represents scanning speed, (x, y) represents the coordinates of the center of the spot, and (x0, y0) represents the coordinates of the initial laser beam position. f represents the mass flow rate, η m Powder utilization rate, represents the powder density, r p represents the mass flow radius, and z represents the unit vector parallel to the laser direction. Since the geometric dimensions of the molten pool are also affected by other factors, it is unrealistic to simulate and take all factors into account. Therefore, the present invention introduces correction factors a and b to correct Q and V respectively. p , that is, Q′=a×Q and V p ′ = b × Vp. In addition, the initial temperature of the model is 293.15 K, and the initial velocity at the exit is 0 m / s. The symmetry plane and the bottom plane are adiabatic boundaries.

[0057] S3: Mesh the established model and establish a transient study step.

[0058] Furthermore, the established model was meshed. The model was divided into three regions to achieve local mesh refinement in the key computational domain, and the sweep method was used to further improve the computational speed and convergence.

[0059] It should be noted that a transient study step is established. The study is set to a time of 1 second, a step size of 0.0005 seconds, and a transient study step. The transient solver includes the absolute tolerance, time stepping, maximum number of iterations, PARDISO solver, and error.

[0060] S4: Conduct laser cladding experiments to process transient simulation results.

[0061] Furthermore, laser cladding experiments were carried out, and the laser parameter combinations were selected as follows: laser power, P (2000W), scanning speed, v (540mm / min), spot diameter, D (3mm) and powder mass flow rate, mf (18g / min). Figure 4 ,The morphological changes of the molten pool are captured by a high-speed camera, and the shape, size and dynamic behavior of the molten pool are analyzed.

[0062] Further, such as Figure 5 , the transient simulation results are post-processed using COMSOL software, specifically the three-dimensional temperature field drawing. Figure 6 , based on the liquidus temperature of the material, the three-dimensional morphology of the molten pool is obtained by numerical simulation.

[0063] Furthermore, the image pro software is used to compare and analyze the size of the experimental molten pool monitoring and the numerical simulation molten pool to determine whether the error is within 10%. Figure 7 The average deviations between the simulation and the melt pool before correction are 26.45% and 22.50% in length and width, respectively. The results show that the error is greater than 10%, so we return to step 3 in the process and repeat the cycle.

[0064] Furthermore, Figure 8 , after introducing the boundary condition correction factor, the dynamic diagram of the numerical simulation molten pool is obtained. Figure 9 Compared to the first cycle, the numerical model results after introducing correction factors a = 1.12 and b = 1.4 respectively show that the average deviation of the simulated melt pool length and width relative to the melt pool monitoring is 8.74% and 5.54%, respectively. The simulation error is less than 10%, indicating that the model has the ability to predict the melt pool morphology.

[0065] Example 2, reference Figure 10-12 , which is an embodiment of the present invention, provides a laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0066] First, based on the numerical simulation model calibrated in Example 2, the process parameter combination (P=1600W, v=540mm / min, D=3mm, mf=18g / min) was changed to further verify the reliability of the calibrated numerical model.

[0067] like Figure 10 , obtain the dynamic development diagram of the melt pool of the simulation calculation of the verification group. Figure 11 ,Based on the real-time monitoring system, the laser cladding molten pool capture image under the verification parameter combination is obtained.

[0068] like Figure 12 The dimensions of the melt pools from the simulated and experimentally measured melt pools were compared for validation purposes. Statistical results show that the average deviations in length and width of the simulated melt pools relative to experimental monitoring were 6.60% and 4.49%, respectively. These results demonstrate the reliability and broad application value of the laser cladding melt pool morphology prediction method based on numerical simulation and real-time monitoring feedback.

[0069] Example 3, an embodiment of the present invention, provides a laser cladding molten pool morphology prediction system based on numerical simulation and monitoring feedback, including a laser cladding single-pass three-dimensional numerical simulation model construction module, a thermophysical property parameter assignment module, and a correction factor introduction module.

[0070] Among them, the laser cladding single-pass three-dimensional numerical simulation model construction module is used to establish a multi-physical field coupling numerical model involving melt flow, heat transfer and cladding layer protrusion; the thermophysical property parameter assignment module is used to capture the dynamic process of the laser cladding molten pool in real time based on the molten pool monitoring system; the correction factor introduction module is used to introduce boundary condition correction factors based on real-time monitoring feedback of the molten pool.

[0071] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program code.

[0072] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0073] More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic devices), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering, or processing in another suitable manner as necessary, and then stored in a computer memory.

[0074] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having logic gate circuits for implementing logical functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc. It should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention and are not intended to be limiting. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications should be encompassed by the claims of the present invention.

[0075] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for predicting the morphology of a laser cladding molten pool based on numerical simulation and monitoring feedback, characterized in that: include: Construct a three-dimensional numerical simulation model of a single laser cladding pass and assign the thermophysical parameters of nonlinear materials to the three-dimensional numerical simulation model of a single laser cladding pass; Add physical fields and couple to set boundary conditions; Mesh the established model and establish a transient study step; Conduct laser cladding experiments and calibrate transient simulation results.

2. The method for predicting the laser cladding molten pool morphology based on numerical simulation and monitoring feedback according to claim 1, characterized in that: The construction of a single-pass laser cladding three-dimensional numerical simulation model and the assignment of nonlinear material thermophysical parameters to the single-pass laser cladding three-dimensional numerical simulation model include establishing a single-pass laser cladding three-dimensional numerical simulation model, adopting symmetric boundary conditions, and setting the size of the substrate.

3. The method for predicting the laser cladding molten pool morphology based on numerical simulation and monitoring feedback according to claim 2, characterized in that: The method comprises constructing a single-pass three-dimensional numerical simulation model of laser cladding, assigning thermophysical parameters of nonlinear materials to the single-pass three-dimensional numerical simulation model of laser cladding, and calculating the specific heat capacity, thermal conductivity, surface tension and density of the cladding powder and the substrate based on JMatPro commercial software; Based on the characteristics of the material's solid-liquid transition, the material's liquidus temperature is obtained as a basis for material assignment and obtaining the simulated molten pool size; Based on the thermophysical parameters of the matrix and powder, they are assigned to the model and expressed as: Among them, φ represents the material thermal property judgment parameter, T, T m 、T l and T s Denote the temperature variable, melting point, liquidus temperature, and solidus temperature, respectively. S(x) denotes a smooth step function. z, z0, and Δz denote the vertical displacement variable, the initial surface level, and the size of the transition zone in the z direction, respectively.

4. The method for predicting laser cladding molten pool morphology based on numerical simulation and monitoring feedback according to claim 3, characterized in that: The physical field addition and coupled boundary condition setting include multi-physical processes of melt flow, heat transfer and cladding layer protrusion involved in the laser cladding molten pool process, respectively introducing laminar flow, fluid heat transfer and deformation geometry physical fields; The Laminar Flow interface and the Fluid Heat Transfer interface are coupled to form the non-isothermal flow and Marangoni convection physics fields; Deformation geometry is used to simulate the process of powder injection, melting, and solidification to form a coating; The influence on the geometry of the molten pool is the laser input energy Q and the movement speed V of the solid-liquid interface caused by powder filling. p , expressed as: Where t represents time, α represents laser absorption rate, P represents laser power, rs represents laser spot radius, v represents scanning speed, (x, y) represents the coordinates of the center of the spot, (x0, y0) represents the coordinates of the initial laser beam position, m f represents the mass flow rate, η m Powder utilization rate, ρ m represents the powder density, r p represents the mass flow radius, z represents the unit vector parallel to the laser direction; Introduce correction factors a and b to correct Q and V p , that is, Q′=a×Q and Vp′=b×Vp.

5. The method for predicting the laser cladding molten pool morphology based on numerical simulation and monitoring feedback according to claim 4, characterized in that: The steps of meshing the established model and establishing a transient study include performing regional meshing based on reliability and rationality; Create a transient study step, study the time and step size, and use the transient study step; Transient solvers include absolute tolerance, time stepping, maximum number of iterations, PARDISO solver, and error.

6. The method for predicting the laser cladding molten pool morphology based on numerical simulation and monitoring feedback according to claim 5, characterized in that: The laser cladding experiment processing transient simulation results includes conducting a laser cladding experiment, selecting a laser parameter combination, capturing the morphological changes of the molten pool by a high-speed camera, and analyzing the shape, size and dynamic behavior of the molten pool; The transient simulation results were post-processed using COMSOL software, and the three-dimensional morphology of the molten pool was obtained based on the liquidus temperature of the material.

7. The method for predicting laser cladding molten pool morphology based on numerical simulation and monitoring feedback according to claim 6, characterized in that: The laser cladding experiment processing transient simulation results include using image pro software to compare and analyze the size of the experimental molten pool monitoring and the numerical simulation molten pool to determine whether the error is within 10%; After introducing the boundary condition correction factor, the dynamic diagram of the numerical simulation melt pool is obtained.

8. A system using the method for predicting laser cladding pool morphology based on numerical simulation and monitoring feedback according to any one of claims 1 to 7, characterized in that: It includes a laser cladding single-pass three-dimensional numerical simulation model construction module, a thermophysical property parameter assignment module, and a correction factor introduction module; The laser cladding single-pass three-dimensional numerical simulation model building module is used to establish a multi-physics field coupling numerical model involving melt flow, heat transfer and cladding layer protrusion; The thermophysical property parameter assignment module is used to capture the dynamic process of the laser cladding molten pool in real time based on the molten pool monitoring system; The correction factor introduction module is used to introduce boundary condition correction factors based on real-time monitoring feedback of the molten pool.

9. A computer 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 laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback are implemented as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the laser cladding molten pool morphology prediction method based on numerical simulation and monitoring feedback according to any one of claims 1 to 7 are implemented.

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