Boring and milling machine stability analysis method, device, equipment and medium

Abstract

The invention relates to a boring and milling machine stability analysis method, device, equipment and medium, and belongs to the technical field of machine tools, the boring and milling machine stability analysis method comprises the following steps: constructing a cutter constitutive model and a workpiece constitutive model, carrying out thermal-mechanical coupling dynamic explicit solution on the cutter constitutive model and the workpiece constitutive model by adopting a Lagrangian grid, three-way cutting force under the face milling and drilling working conditions is calculated; and performing statics general step analysis on the constructed finite element analysis model of the boring and milling machine by taking the three-way cutting force as a constraint condition to obtain stress distribution of the boring and milling machine under the processing load, and determining the stability of the boring and milling machine based on the stress distribution, so that the stability of the boring and milling machine is improved.

Description

Technical Field

[0001] The invention relates to the technical field of machine tools, and in particular to a method, device, equipment and medium for analyzing the stability of a boring and milling machine. Background Art

[0002] Boring and milling machines are mainly used in important industries such as aerospace, hydropower, and shipbuilding. They are suitable for processing complex features such as drilling, milling, and milling grooves of large and super-large parts. Due to their high-efficiency and high-precision milling functions, they are currently widely used in the processing of large parts such as supports for large machinery, oil drilling platforms, and large water conservancy generators. They can process end faces, inner holes, inclined holes, and curved surfaces of various large-sized, high-hardness, and difficult-to-process materials. The machine tool has milling, boring, drilling, reaming, tapping and other functions. When equipped with a rotary worktable, it can realize the processing of multiple surfaces of the workpiece in one clamping, so that one machine can be used for multiple purposes, thereby improving the machine tool production efficiency of the workpiece.

[0003] In order to achieve precision machining of large parts, a lot of research has been carried out on cutting machining. Cutting force is an important physical quantity that characterizes the cutting process, and it is also the basis for studying load, deformation, vibration, etc. Commonly used cutting force modeling methods include empirical formulas, analytical models, mechanical models, finite element models, etc. The existing cutting process load prediction methods are mostly aimed at working conditions with small material removal and small tool size, with the goal of precision machining, reducing tool wear, and optimizing surface machining quality.

[0004] However, face milling with disc milling cutters has the advantages of large cutting area and high processing efficiency, and is often used in the plane processing of large components. For the disc milling processing of gantry milling machines with a size of several hundred millimeters, it is necessary to build a large-scale cutting process prediction model. Heavy-loaded boring and milling machines often use large-sized disc milling cutters, accompanied by a large number of deep hole processing processes, with a large amount of material removal, resulting in high cutting loads and easy deformation of the spindle, which leads to low stability during the cutting process of the boring and milling machine. Summary of the invention

[0005] In view of this, it is necessary to provide a boring and milling machine stability analysis method, device, equipment and medium to solve the technical problem of low stability during the cutting process of large components of the boring and milling machine.

[0006] In order to solve the above problems, the present invention provides a boring and milling machine stability analysis method, comprising: Constructing a tool constitutive model and a workpiece constitutive model, using Lagrangian grids to perform thermal-mechanical coupling dynamic explicit solutions to the tool constitutive model and the workpiece constitutive model, and calculating three-dimensional cutting forces under face milling and drilling conditions; Taking the three-dimensional cutting force as a constraint condition, a static general step analysis is performed on the constructed finite element analysis model of the boring and milling machine to obtain the stress distribution of the boring and milling machine under the machining load, and the stability of the boring and milling machine is determined based on the stress distribution.

[0007] In a possible implementation, the construction of a three-dimensional solid model of a center-mounted planer-type boring and milling machine includes: The tool constitutive model and the workpiece constitutive model are solved dynamically and explicitly using Lagrangian grids to calculate the three-dimensional cutting forces under face milling and drilling conditions, including: Acquire the properties of the tool and the workpiece, wherein the properties include thermophysical properties, material constitutive properties, friction equations, and dynamic properties; Setting working condition parameters, wherein the working condition parameters at least include feed speed, rotation speed, and cutting depth; After assigning the attribute to the tool constitutive model and the workpiece constitutive model, a cutting finite element simulation model is constructed based on the tool constitutive model and the workpiece constitutive model; Based on the working condition parameters, the cutting finite element simulation model is simulated to obtain the three-dimensional cutting forces under face milling and drilling conditions.

[0008] In a possible implementation, the tool includes a disc milling cutter and a drill bit, and the disc milling cutter is composed of a plurality of indexable inserts.

[0009] In a possible implementation, the calculation formula of the workpiece constitutive model is: , , , , , in, is the flow stress of the material under the conditions of strain, strain rate and temperature, is the strain hardening term, is the strain rate strengthening term, is the temperature thermal softening term, is the yield stress, is the initial deformation temperature, is the current deformation temperature, is the adiabatic temperature, is the plastic strain, is the plastic strain rate, is the reference strain, is the reference strain rate, , is the material constant, , , , , , is the constitutive coefficient.

[0010] In a possible implementation, taking the three-dimensional cutting force as a constraint condition, performing a static general step analysis on the constructed finite element analysis model of the boring and milling machine to obtain the stress distribution of the boring and milling machine under the machining load includes: A finite element analysis model of a boring and milling machine is constructed, the three-dimensional cutting force is coupled to the finite element analysis model of the boring and milling machine, and after a gravity load is applied to the boring and milling machine, a static general step analysis is performed on the finite element analysis model of the boring and milling machine to obtain the stress distribution of the boring and milling machine under the machining load.

[0011] In a possible implementation, constructing a finite element analysis model of a boring and milling machine includes: A plurality of finite element analysis models of the boring and milling machine are established according to the spindle position and the spindle overhang of the boring and milling machine, wherein the spindle position includes the bottom, the middle and the top, and the spindle overhang includes the first spindle overhang, the second spindle overhang and the third spindle overhang.

[0012] In a possible implementation manner, determining the stability of the boring and milling machine based on the stress distribution includes: A safety threshold is set, the yield strength of the boring and milling machine material is determined, the safety factor of the boring and milling machine is calculated based on the stress distribution and the yield strength, and the stability of the boring and milling machine is judged based on the safety factor and the safety threshold.

[0013] On the other hand, the present invention also provides a boring and milling machine stability analysis device, comprising: A cutting force acquisition module is used to construct a tool constitutive model and a workpiece constitutive model, and to solve the tool constitutive model and the workpiece constitutive model using a Lagrangian grid for a thermal-mechanical coupling dynamic explicit solution to calculate the three-dimensional cutting force under face milling and drilling conditions; The stability judgment module is used to perform a static general step analysis on the constructed boring and milling machine finite element analysis model with the three-dimensional cutting force as a constraint condition, obtain the stress distribution of the boring and milling machine under the processing load, and determine the stability of the boring and milling machine based on the stress distribution.

[0014] In another aspect, the present invention further provides an electronic device, comprising: a processor and a memory; The memory stores a computer-readable program executable by the processor; When the processor executes the computer-readable program, the steps in the boring and milling machine stability analysis method as described above are implemented.

[0015] On the other hand, the present invention also provides a computer-readable storage medium, which stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps in the boring and milling machine stability analysis method as described above.

[0016] The beneficial effects of the present invention are: taking the three-dimensional cutting force as the constraint condition, a static general step analysis is performed on the constructed finite element analysis model of the boring and milling machine, the stress distribution of the boring and milling machine under the processing load is obtained, the stability of the boring and milling machine is determined based on the stress distribution, the cutting force load in the processing process is introduced into the finite element analysis model of the boring and milling machine as a boundary condition, the large-scale milling and drilling process is simulated, the stress distribution of the boring and milling machine under the processing load is explored, and the stability of the boring and milling machine is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A flow chart of an embodiment of a method for analyzing the stability of a boring and milling machine provided by the present invention; Figure 2 A schematic diagram of three-dimensional cutting forces of a disc milling cutter face milling in the boring and milling machine stability analysis method provided by the present invention; Figure 3 A schematic diagram of three-dimensional cutting forces of drilling for the boring and milling machine stability analysis method provided by the present invention; Figure 4 A schematic diagram of applying coupled concentrated force in the boring and milling machine stability analysis method provided by the present invention; Figure 5a A schematic diagram of stress distribution of a first group of finite element simulation models of boring and milling machines in the boring and milling machine stability analysis method provided by the present invention; Figure 5b A schematic diagram of stress distribution of the fifth group of boring and milling machine finite element simulation models of the boring and milling machine stability analysis method provided by the present invention; Figure 6a Schematic diagram of column stress results when the spindle is located at the bottom and the spindle overhang is 0% for the boring and milling machine stability analysis method provided by the present invention Figure 6b Schematic diagram of column stress results when the spindle is located in the middle and the spindle overhang is 0% for the boring and milling machine stability analysis method provided by the present invention Figure 6c A schematic diagram of the column stress results when the spindle of the boring and milling machine stability analysis method provided by the present invention is located at the top and the spindle overhang is 0%; Figure 6d A schematic diagram of the column stress results when the spindle of the boring and milling machine stability analysis method provided by the present invention is located at the top and the spindle overhang is 100%; Figure 7A schematic structural diagram of an embodiment of a boring and milling machine stability analysis device provided by the present invention; Figure 8 A schematic structural diagram of an embodiment of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0018] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0019] The present invention discloses a method, device, equipment and medium for analyzing the stability of a boring and milling machine, which can be used in a computer. The method, equipment or computer-readable storage medium involved in the present invention can be integrated with the above-mentioned equipment or can be relatively independent.

[0020] A specific embodiment of the present invention discloses a method for analyzing the stability of a boring and milling machine, which can be executed by a computer, and specifically by one or more processors of the computer. Figure 1 As shown in the figure, the stability analysis method of boring and milling machine includes: S101, constructing tool constitutive model and workpiece constitutive model, using Lagrangian grid to perform thermal-mechanical coupling dynamic explicit solution on tool constitutive model and workpiece constitutive model, and calculating three-dimensional cutting force under face milling and drilling conditions; S102. Taking the three-dimensional cutting force as a constraint condition, a static general step analysis is performed on the constructed finite element analysis model of the boring and milling machine to obtain the stress distribution of the boring and milling machine under the machining load, and the stability of the boring and milling machine is determined based on the stress distribution.

[0021] Among them, the simulation software AdvantEdge is used to construct the tool constitutive model, workpiece constitutive model and boring and milling machine finite element analysis model. Among them, the workpiece constitutive model is a Power-Law model, that is, a power-law model, which supports the import of tools of any shape from the outside, and provides a dynamic explicit solution of thermal-mechanical coupling based on Lagrangian grid. In the position with large deformation gradient, it will automatically adopt an adaptive redivision strategy for mesh refinement, which can well capture the influence of tool shape on the cutting process; the three-dimensional cutting force under face milling and drilling conditions is imported into the finite element analysis model of the boring and milling machine as a constraint condition, and the stress condition of the boring and milling machine under the processing load is simulated and calculated, which can accurately predict the stress distribution of the boring and milling machine during the processing process, and has certain guiding significance for the design of the boring and milling machine.

[0022] Compared with the prior art, the boring and milling machine stability analysis method provided in this embodiment constructs a tool constitutive model and a workpiece constitutive model, and uses Lagrangian grid to dynamically explicitly solve the tool constitutive model and the workpiece constitutive model using thermal-mechanical coupling, and calculates the three-dimensional cutting force under face milling and drilling conditions; with the three-dimensional cutting force as a constraint condition, a static general step analysis is performed on the constructed boring and milling machine finite element analysis model to obtain the stress distribution of the boring and milling machine under the machining load, and the stability of the boring and milling machine is determined based on the stress distribution, and the cutting force load in the machining process is introduced into the finite element analysis model of the boring and milling machine as a boundary condition, and the large-scale milling and drilling processes are simulated to obtain the stress distribution of the boring and milling machine under the machining load, thereby improving the stability of the boring and milling machine.

[0023] In some embodiments, in step S101, a tool constitutive model and a workpiece constitutive model are constructed, and the tool constitutive model and the workpiece constitutive model are dynamically explicitly solved by thermal coupling of Lagrangian grid, and the three-dimensional cutting force under face milling and drilling conditions is calculated. The geometric features of the disc milling cutter and the drill bit are imported into the finite element analysis software to construct a tool constitutive model. The tool and the workpiece are both constructed by Lagrangian grid, wherein the tool edge position grid is manually refined, the minimum unit size is 2 μm, and the unit attribute is a six-node quadratic triangular unit, which can generate quadratic interpolation and capture the linear stress distribution within each unit. The disc milling cutter has a diameter of 200 mm and a drill bit has a diameter of 100 mm. The disc milling cutter is composed of multiple indexable blades, that is, the disc milling cutter is composed of 12 indexable blades. For this non-standard disc milling cutter, it needs to be manually imported into the simulation software, and the blade and the cutter body are checked so that the software can identify and assign materials. The process of dynamically explicitly solving the model by thermal coupling of Lagrangian grid is as follows: obtaining the properties of the tool and the workpiece, Among them, the properties include thermal physical properties, material constitutive properties, friction equations, and dynamic properties. According to the actual working conditions, the working condition parameters are set, wherein the working condition parameters at least include feed speed, rotation speed, and cutting depth. The actual working conditions are divided into disc milling cutter face milling and drill drilling. For the 45 steel face milling process of the boring and milling machine, the set working condition parameters are: rotation speed 250r / min, cutting depth 8mm, feed speed 150mm / min; for the 45 steel drilling process, the working condition parameters are set to: rotation speed 300r / min, feed speed 100mm / min; after assigning the properties to the tool constitutive model and the workpiece constitutive model (Power-Law model), a cutting finite element simulation model is constructed based on the tool constitutive model and the workpiece constitutive model; based on the working condition parameters, the cutting finite element simulation model is simulated to obtain the three-dimensional cutting force under face milling and drilling conditions; the workpiece material is AISI-1045 steel, and the chemical composition of the AISI-1045 steel material is obtained through the software material library. For the chemical composition of the AISI-1045 steel material, please refer to Table 1. Table 1

[0024] The physical properties of AISI-1045 steel are shown in Table 2. Table 2

[0025] Thermal properties of AISI-1045 steel, see Table 3, Table 3

[0026] The calculation formula of the Power-Law model is: , , , , , in, is the flow stress of the material under the conditions of strain, strain rate and temperature, is the strain hardening term, is the strain rate strengthening term, is the temperature thermal softening term, is the yield stress, is the initial deformation temperature, is the current deformation temperature, is the adiabatic temperature, is the plastic strain, is the plastic strain rate, is the reference strain, is the reference strain rate, , is the material constant, , , , , , is the constitutive coefficient, and the constitutive parameters of the Power-Law model for cutting simulation AISI-1045 steel material are shown in Table 4. Table 4

[0027] Through milling and drilling simulation, the cutting force of the boring and milling machine under face milling and drilling conditions is obtained. The stable section is extracted and the average value is calculated. The three-dimensional cutting force results are obtained. The three-dimensional cutting force is the load force on the X, Y, and Z axes. The three-dimensional cutting force diagram of the disc milling cutter face milling can be found in Figure 2 For the three-dimensional cutting force diagram of drilling, please refer to Figure 3For the three-way cutting force results, please refer to Table 5. Table 5

[0028] Through AdvantEdge finite element processing simulation software, the load during boring and milling machine processing can be calculated. Taking drill drilling as an example, the load forces on the X, Y, and Z axes are X=17829.5N, Y=8530.3N, and Z=209998N respectively.

[0029] In some embodiments, in step S102, a static general step analysis is performed on the constructed boring and milling machine finite element analysis model with the three-dimensional cutting force as a constraint condition to obtain the stress distribution of the boring and milling machine under the processing load, and the three-dimensional cutting force is coupled to the boring and milling machine finite element analysis model, and after the gravity load is applied to the boring and milling machine, a static general step analysis is performed on the boring and milling machine finite element analysis model to obtain the stress distribution of the boring and milling machine under the processing load; multiple groups of boring and milling machine finite element analysis models are established according to the position of the boring and milling machine spindle and the spindle overhang, wherein the spindle position includes the bottom, the middle and the top, and the spindle overhang includes the first spindle overhang (0%), the second spindle overhang (50%) and the third spindle overhang (100%), and a total of 9 groups of boring and milling machine finite element analysis models are established, and the overall material of the boring and milling machine is HT300, with a Young's modulus of 130 Gpa and a density of 7300. , Poisson's ratio is 0.25, meshing of the boring and milling machine is performed in the simulation software, the global size is 20, the mesh unit is tetrahedron, and the mesh type is C3D4 unit; the three-way cutting force is coupled to the shaft end, that is, the coupled concentrated force is applied to the boring and milling machine. For the schematic diagram of applying the coupled concentrated force, please refer to Figure 4 At the same time, a gravity load is applied to the entire boring and milling machine, and the movement and rotation of the bottom of the boring and milling machine in the X, Y, and Z directions are constrained. The analysis step adopts the general static analysis step, opens the large geometric deformation, and the initial step length is 0.01. The finite element analysis model of the boring and milling machine is simulated and analyzed to obtain the stress distribution of the boring and milling machine under the processing load, that is, the stress distribution of the boring and milling machine under the drilling-gravity load. The stress distribution diagram of the first group of boring and milling machine finite element simulation models can be found in Figure 5a The first group of boring and milling machine finite element simulation models is a boring and milling machine finite element simulation model with the spindle position at the top and the spindle overhang of 0% under drilling-gravity load. The stress distribution diagram of the fifth group of boring and milling machine finite element simulation models can be found in Figure 5b The fifth group of boring and milling machine finite element simulation models is a boring and milling machine finite element simulation model in which the spindle position of the boring and milling machine is in the middle and the spindle overhang is 50% under drilling-gravity load.

[0030] The drilling-gravity load will have different effects on the gantry according to the different spindle extension lengths of the boring and milling machine. When the spindle overhang is the same, the maximum stresses under the three groups of positions (bottom, middle, and top) are basically the same. When the extension is 0%, the average stress is 44.20 MPa; when the extension is 50%, the average stress is 54.07 MPa; when the extension is 100%, the average stress is 88.75 MPa. However, when the spindle is at the same height, the increase in the spindle overhang will significantly increase the maximum stress of the gantry, that is, the longer the spindle extension length, the greater the load on the gantry. Please refer to Table 6 for the maximum stress under the drilling-gravity load. Table 6

[0031] Since the maximum stress of the boring and milling machine after loading occurs at the end of the spindle, it is not comprehensive to only consider the spindle force for the overall analysis of the boring and milling machine. Therefore, the spindle and saddle parts with the largest stress are removed, and the main body of the gantry is retained for analysis. Taking the spindle overhang of 0% as an example, when the spindle is at the bottom, the maximum stress of the gantry is 8.7 MPa; when the spindle is in the middle, the maximum stress of the gantry is 12.11 MPa; when the spindle is at the top, the maximum stress of the gantry is 17.13 MPa. The main stress concentration part of the gantry is at the rear leg of the column, and as the spindle position is extended, the stress on the column gradually increases. For the schematic diagram of the column stress results when the spindle is at the bottom and the spindle overhang is 0%, please refer to Figure 6a , for a schematic diagram of the column stress results with the spindle located in the middle and the spindle overhang being 0%, see Figure 6b , for a schematic diagram of the column stress results with the spindle at the top and the spindle overhang being 0%, see Figure 6c When the spindle is at the top, the stress will spread to the entire gantry. At the same time, the stress analysis of the column at the same height and different overhang conditions is carried out. The schematic diagram of the column stress results when the spindle is at the top and the spindle overhang is 100% can be found in Figure 6d , with the main axis at the top and the extension lengths of 0% and 100% respectively, as shown in the figure. Figure 6c as well as Figure 6d As shown, the results are: the stress conditions of the test bench body are basically the same, which shows that the influence of the spindle extension length on the column is very small. However, considering the overall structure, under the same load, the longer the spindle extension length, the greater the torque on the end of the shaft, which causes stress concentration at the end of the spindle.

[0032] The stability of the boring and milling machine is judged based on the stress distribution, the safety threshold is set, the yield strength of the boring and milling machine material is determined, the safety factor of the boring and milling machine is calculated based on the stress distribution and yield strength, and the stability of the boring and milling machine is judged based on the safety factor and the safety threshold. When the safety factor is greater than the safety threshold, it means that the boring and milling machine has good strength under drilling-gravity load, that is, good stability. Taking the maximum stress of 17.45 MPa in the column as an example, the equivalent stress of the column in 9 groups of simulation results is in the range of 8 to 17 MPa. When the yield strength of the HT300 material is 300 MPa, the calculation formula of the safety factor of the boring and milling machine is: , in, is the safety factor, is the yield strength of the material, is the maximum stress, and its safety threshold is 17. The calculated safety factor is 17.19. It can be seen that the safety factor of the gantry body is above 17, that is, the safety factor of the boring and milling machine is above 17, indicating that the boring and milling machine has good strength and stability under the working load.

[0033] In order to better implement the boring and milling machine stability analysis method in the embodiment of the present invention, based on the boring and milling machine stability analysis method, correspondingly, Figure 7 As shown, the embodiment of the present invention further provides a boring and milling machine stability analysis device, and the boring and milling machine stability analysis device 700 includes: The cutting force acquisition module 701 is used to construct a tool constitutive model and a workpiece constitutive model, and to solve the tool constitutive model and the workpiece constitutive model using a Lagrangian grid for a thermal-mechanical coupling dynamic explicit solution to calculate the three-dimensional cutting force under face milling and drilling conditions; The stability judgment module 702 is used to perform a static general step analysis on the constructed boring and milling machine finite element analysis model with the three-dimensional cutting force as a constraint condition, obtain the stress distribution of the boring and milling machine under the processing load, and determine the stability of the boring and milling machine based on the stress distribution.

[0034] like Figure 8 As shown, the present invention also provides an electronic device 800 , which can be a computing device such as a mobile terminal, a desktop computer, a notebook, a palmtop computer, a server, etc. The electronic device 800 includes a processor 801 , a memory 802 , and a display 803 . Figure 8 Only some components of the electronic device 800 are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0035] In some embodiments, the memory 802 may be an internal storage unit of the electronic device 800, such as a hard disk or memory of the electronic device 800. In other embodiments, the memory 802 may also be an external storage device of the electronic device 800, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 800. Further, the memory 802 may also include both an internal storage unit of the electronic device 800 and an external storage device. The memory 802 is used to store application software and various data installed in the electronic device 800, such as program codes installed in the electronic device 800. The memory 802 may also be used to temporarily store data that has been output or is to be output. In one embodiment, a boring and milling machine stability analysis program is stored on the memory 802, and the boring and milling machine stability analysis program can be executed by the processor 801, thereby realizing the boring and milling machine stability analysis method of each embodiment of the present invention.

[0036] In some embodiments, the processor 801 may be a central processing unit (CPU), a microprocessor or other data processing chip, and is used to run program codes or process data stored in the memory 802, such as a boring and milling machine stability analysis method.

[0037] In some embodiments, the display 803 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch device, etc. The display 803 is used to display identification information of the boring and milling machine stability analysis program and to display a visual user interface. The components 801-803 of the electronic device 800 communicate with each other via a system bus.

[0038] In some embodiments, when the processor 801 executes the boring and milling machine stability analysis program in the memory 802, the various steps in the boring and milling machine stability analysis method described in the above embodiments are implemented. Since the boring and milling machine stability analysis method has been described in detail above, it will not be repeated here.

[0039] Accordingly, the present invention also provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, the steps or functions in the boring and milling machine stability analysis method provided by the above-mentioned method embodiments can be implemented.

[0040] In summary, the boring and milling machine stability analysis method, device, equipment and medium provided by the present invention construct a tool constitutive model and a workpiece constitutive model, and use Lagrangian grid to dynamically explicitly solve the tool constitutive model and the workpiece constitutive model using thermal-mechanical coupling to calculate the three-dimensional cutting force under face milling and drilling conditions; with the three-dimensional cutting force as a constraint condition, the constructed boring and milling machine finite element analysis model is subjected to a static general step analysis to obtain the stress distribution of the boring and milling machine under machining load, and the stability of the boring and milling machine is determined based on the stress distribution, thereby improving the stability of the boring and milling machine.

[0041] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0042] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for analyzing the stability of a boring and milling machine, characterized in that: include: Constructing a tool constitutive model and a workpiece constitutive model, using Lagrangian grids to perform thermal-mechanical coupling dynamic explicit solutions to the tool constitutive model and the workpiece constitutive model, and calculating three-dimensional cutting forces under face milling and drilling conditions; Taking the three-dimensional cutting force as a constraint condition, a static general step analysis is performed on the constructed finite element analysis model of the boring and milling machine to obtain the stress distribution of the boring and milling machine under the machining load, and the stability of the boring and milling machine is determined based on the stress distribution.

2. The boring and milling machine stability analysis method according to claim 1, characterized in that: The tool constitutive model and the workpiece constitutive model are solved dynamically and explicitly using Lagrangian grids for thermal-mechanical coupling to calculate the three-dimensional cutting forces under face milling and drilling conditions, including: Acquire the properties of the tool and the workpiece, wherein the properties include thermophysical properties, material constitutive properties, friction equations, and dynamic properties; Setting working condition parameters, wherein the working condition parameters at least include feed speed, rotation speed, and cutting depth; After assigning the attribute to the tool constitutive model and the workpiece constitutive model, a cutting finite element simulation model is constructed based on the tool constitutive model and the workpiece constitutive model; Based on the working condition parameters, the cutting finite element simulation model is simulated to obtain the three-dimensional cutting forces under face milling and drilling conditions.

3. The boring and milling machine stability analysis method according to claim 2, characterized in that: The tool comprises a disc milling cutter and a drill bit, wherein the disc milling cutter is composed of a plurality of indexable blades.

4. The boring and milling machine stability analysis method according to claim 2, characterized in that: The calculation formula of the workpiece constitutive model is: ， ， ， ， ， in, is the flow stress of the material under the conditions of strain, strain rate and temperature, is the strain hardening term, is the strain rate strengthening term, is the temperature thermal softening term, is the yield stress, is the initial deformation temperature, is the current deformation temperature, is the adiabatic temperature, is the plastic strain, is the plastic strain rate, is the reference strain, is the reference strain rate, , is the material constant, , , , , , is the constitutive coefficient.

5. The boring and milling machine stability analysis method according to claim 4, characterized in that: The method of performing a static general step analysis on the constructed boring and milling machine finite element analysis model with the three-dimensional cutting force as a constraint condition to obtain the stress distribution of the boring and milling machine under the machining load includes: A finite element analysis model of a boring and milling machine is constructed, the three-dimensional cutting force is coupled to the finite element analysis model of the boring and milling machine, and after a gravity load is applied to the boring and milling machine, a static general step analysis is performed on the finite element analysis model of the boring and milling machine to obtain the stress distribution of the boring and milling machine under the machining load.

6. The boring and milling machine stability analysis method according to claim 5, characterized in that: The construction of the finite element analysis model of the boring and milling machine includes: A plurality of finite element analysis models of the boring and milling machine are established according to the spindle position and the spindle overhang of the boring and milling machine, wherein the spindle position includes the bottom, the middle and the top, and the spindle overhang includes the first spindle overhang, the second spindle overhang and the third spindle overhang.

7. The boring and milling machine stability analysis method according to claim 6, characterized in that: Determining the stability of the boring and milling machine based on the stress distribution includes: A safety threshold is set, the yield strength of the boring and milling machine material is determined, the safety factor of the boring and milling machine is calculated based on the stress distribution and the yield strength, and the stability of the boring and milling machine is judged based on the safety factor and the safety threshold.

8. A boring and milling machine stability analysis device, characterized in that: include: A cutting force acquisition module is used to construct a tool constitutive model and a workpiece constitutive model, and to solve the tool constitutive model and the workpiece constitutive model using a Lagrangian grid for a thermal-mechanical coupling dynamic explicit solution to calculate the three-dimensional cutting force under face milling and drilling conditions; The stability judgment module is used to perform a static general step analysis on the constructed boring and milling machine finite element analysis model with the three-dimensional cutting force as a constraint condition, obtain the stress distribution of the boring and milling machine under the processing load, and determine the stability of the boring and milling machine based on the stress distribution.

9. An electronic device, characterized in that: including memory and processor; The memory stores a computer-readable program executable by the processor; When the processor executes the computer-readable program, the steps in the boring and milling machine stability analysis method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps in the boring and milling machine stability analysis method as described in any one of claims 1-7.

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