Simulation piece design method for simulating disc forging pre-rotation process

Abstract

The invention relates to a simulation part design method for simulating a disc forging pre-rotation process, and belongs to the field of aero-engine tests. The method solves at least one problem that the existing pre-rotation process simulation method for the high-temperature alloy large disc forge piece has a large gap between the simulation result and the actual simulation result, the simulation efficiency is low, and the mechanical property change of the pre-rotated material is difficult to accurately evaluate. The simulation part design method comprises the following steps: S1, establishing an initial model; s2, simplifying the model; s3, judging whether linear elastic mechanical analysis results of the initial model and the simplified model are consistent or not; s4, optimizing the rotating speed in linear elastic mechanical analysis, or adjusting the simplified model, and taking the simplified model and the rotating speed which can generate consistent results as a simulation part model and a process test rotating speed; and S5, making a simulation part based on the simulation part model, and carrying out a pre-rotation test at a process test rotating speed. According to the invention, the stress-strain and performance change of the actual disc forge piece in the pre-rotation process can be accurately and efficiently simulated.

Description

Technical Field

[0001] The invention relates to the technical field of aero-engine testing, and in particular to a simulation part design method for simulating a pre-rotation process of a disc forging. Background Art

[0002] The hot end rotating parts of aircraft engines are mainly made of high-temperature alloys, including high-pressure and low-pressure turbine discs, compressor discs, comb discs, etc. These high-temperature alloy disc forgings will inevitably introduce residual stress during the forging and heat treatment processes. Excessive residual stress will affect the dimensional stability of these disc forgings during service, thereby affecting the engine's working efficiency and even causing failures.

[0003] The pre-rotation process is a new method for eliminating residual stress in high-temperature alloy disc forgings in recent years. Most of the research on the pre-rotation process is currently focused on the parameter control of the pre-rotation process itself. However, since the high-temperature alloy disc forgings of aircraft engines are generally large in size and high in cost, if the rotation process parameters are not appropriate, the expected internal stress control effect may not be achieved, resulting in a waste of raw materials. In the prior art, although some people have applied computer simulation technology to simulate the pre-rotation process in an attempt to find suitable rotation process parameters through simulation methods, these computer simulation methods have problems such as a large gap between the simulation results and the actual situation and low simulation efficiency when simulating the pre-rotation process. These bottleneck problems limit its development and application. Summary of the invention

[0004] In view of the above analysis, the present invention aims to provide a simulation part design method for simulating the pre-rotation process of disc forgings, so as to solve at least one of the following problems existing in the existing simulation method for the pre-rotation process of large disc forgings of high-temperature alloys: (1) there is a large gap between the simulation results and the actual situation; (2) the simulation efficiency is low; (3) it is difficult to accurately evaluate the changes in the mechanical properties of the material after pre-rotation.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] The present invention provides a simulation part design method for simulating a pre-rotation process of a disc forging, the method comprising the following steps:

[0007] S1. Establish the initial model of the disc forging;

[0008] S2. Based on the stress-strain results of linear elastic mechanics analysis of the initial model, the structural features that have no obvious structural strength correlation in the initial model are eliminated; then the size is reduced to obtain a simplified model;

[0009] S3, performing a linear elastic mechanics analysis on the simplified model to obtain stress-strain results, and determining whether the stress-strain results of the linear elastic mechanics analysis of the initial model and the linear elastic mechanics analysis of the simplified model are consistent;

[0010] S4. Based on the judgment result of S3, if there is inconsistency, return to S3 to optimize the rotation speed in the linear elastic mechanics analysis, or return to S2 to adjust the simplified model and perform S3, through iterative optimization, until the stress-strain results of S2 and S3 are consistent, and the simplified model and rotation speed that can produce consistent stress-strain results are used as the simulation part model and process test rotation speed respectively;

[0011] S5. Based on the simulation part model of S4, a simulation part is manufactured and a pre-rotation test is performed at the process test rotation speed to verify the accuracy and reliability of the simulation part model and the simulation part in simulating the actual disc forging pre-rotation process.

[0012] Furthermore, in step S2, the size reduction ratio is controlled within a range of 50-75%.

[0013] Further, in step S2, the size reduction ratio also satisfies: a plurality of standard specimens for mechanical property testing can be taken out from the simulation part made based on the simulation part model in S4; step S5 also includes: after the pre-rotation test, a plurality of standard specimens are taken out from the simulation part, and the material mechanical properties of the standard specimens are obtained through mechanical property testing, and the changes in the material mechanical properties of the disc forging after the pre-rotation process are evaluated based on the material mechanical properties of the standard specimens.

[0014] Further, in step S1, the disc forging is a disc-shaft integrated forging with rotational symmetry, including a cylindrical body, one or more stepped inner holes are opened inside the cylindrical body, and the outer wall of the cylindrical body extends vertically outward to form one or more disc-shaped structures, and the central axes of all the stepped inner holes coincide with the central axis of the cylindrical body.

[0015] Furthermore, in step S1, the initial model is a two-dimensional axisymmetric geometric model.

[0016] Furthermore, in step S2, the main step of simplification includes: removing the thin-walled area above the step inner hole in the disc forging, and only retaining the axially 5% to 15% thin-walled area close to the step inner hole.

[0017] Furthermore, the main step of simplification also includes: removing the thick-walled area between the other end of the disc forging away from the thin-walled area and the adjacent disc-shaped structure, but retaining the axial 50%-70% thick-walled area close to the adjacent disc-shaped structure.

[0018] Furthermore, the linear elastic mechanics analysis includes: model preparation, initial condition setting, boundary conditions and load application; wherein the initial condition setting includes: initial stress is set to zero, initial temperature is set to room temperature;

[0019] The boundary conditions and load application include: fixing the radial displacement of the upper and lower end surfaces of the model, and then applying a rotation speed load to the entire model.

[0020] Further, the linear elastic mechanics analysis includes: material property definition and mesh division; wherein the material property definition includes: defining Young's modulus as 210-220 GPa, Poisson's ratio as 0.25-0.35, room temperature yield strength as 1100-1150 MPa, and room temperature tensile strength as 1500-1550 MPa; and / or,

[0021] The grid division includes: selecting a two-dimensional quadrilateral unit grid as the grid type, the grid size at the transition right angle of the model is 0.1 mm to 0.5 mm, and the grid size of the remaining parts is 1 mm to 2 mm.

[0022] Further, step S4 specifically includes the following steps:

[0023] S41. If the distribution trend of stress-strain results is consistent but the order of magnitude is inconsistent, use the parametric simulation function in the finite element analysis software to optimize the rotation speed of the linear elastic mechanics analysis in S3 until the equivalent rotation speed is determined, which can make the distribution trend and order of magnitude of the stress-strain results of S2 and S3 consistent;

[0024] S42. If the distribution trends of the stress-strain results are inconsistent, return to S2, adjust the structural features and / or dimensional scaling that have no obvious structural strength correlation, and then proceed to S3.

[0025] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0026] The present invention provides a simulation part design method for simulating a pre-rotation process of a disc forging, which realizes accurate and efficient simulation of stress, strain and performance changes of an actual disc forging in the pre-rotation process.

[0027] (1) The "simulated part model + process test rotation speed" determined by the method of the present invention can accurately and reliably predict the internal stress regulation effect of the actual disc forging after the pre-rotation process, thereby better guiding the optimization of process parameters and making more scientific and accurate process decisions, which in turn helps to improve the quality of large high-temperature alloy disc forgings. Specifically, the present invention reasonably simplifies the structure of the initial model of the disc forging and performs size reduction based on the results of linear elastic mechanics analysis of the disc forging to obtain a simplified model; based on the comparison of the results of linear elastic mechanics analysis of the simplified model with the results of the initial model, the simplified model and / or the rotation speed are optimized to find a "simplified model" and "rotation speed" that can ensure the consistency of stress-strain distribution of the "initial model" and the "simplified model", and preliminarily determine them as the "simulation part model" and "process test rotation speed"; a pre-rotation test is carried out based on the "simulation part model" and the "process test rotation speed", and through experimental verification, it is further ensured that the results of the pre-rotation simulation and process test based on the "simulation part model" and the "process test rotation speed" are consistent with the results of the actual disc forging after pre-rotation. In other words, it is ensured that the difference between the results of the pre-rotation simulation and process test based on the "simulation part model + process test rotation speed" and the results of the actual disc forging after pre-rotation is very small.

[0028] (2) When simplifying the model, reasonable elimination of structural features and dimensional scaling can reduce calculations and improve the computational efficiency of pre-rotation computer simulation based on "simulation model + process test speed"; compared with the existing simulation method, the "simulation model + process test speed" obtained based on the design method of the present invention is more accurate when simulating the actual disc forging pre-rotation process, and the efficiency is also significantly improved.

[0029] (3) In some preferred embodiments, the size reduction ratio of the simulated disc is controlled at 50-75%; such a setting can achieve the best balance between process feasibility and cost-effectiveness. Furthermore, the size reduction ratio also satisfies: multiple standard specimens for mechanical property testing can be taken out from the simulated part made based on the "simulated part model" so as to carry out mechanical property testing after the pre-rotation test. Since the "simulated part model + process test speed" can perform high-precision simulation of the physical phenomena (such as material deformation, stress state, etc.) of the actual disc forging during the pre-rotation process and after rotation, the mechanical property test results of the standard specimens taken out from the simulated part can be used as a reliable basis for evaluating the changes in the mechanical properties of the actual disc forging after pre-rotation, thereby providing a more comprehensive scientific basis for determining the optimal rotation process parameters. Based on "taking multiple standard specimens from the same simulated part", it helps to ensure the consistency and comparability of the mechanical property test results and improve the reliability and statistical significance of the test data.

[0030] (4) In some preferred embodiments, for a disk-shaft integrated forging with rotational symmetry, a two-dimensional axisymmetric geometric model is used for modeling, which can significantly reduce the amount of calculation and the number of grids, while maintaining sufficient accuracy to capture the key stress and strain distributions, thereby more efficiently performing subsequent simulation analysis and optimizing one or more of the disk forging structural features, dimensional scaling, and rotational speed.

[0031] (5) In some preferred embodiments, for the disk-shaft integrated forging with rotational symmetry, the simplified method adopted is preferably to remove most of the thin-walled area above the step inner hole. Further preferably, the thick-walled area between the other end of the disk forging away from the thin-walled area and the adjacent disk-shaped structure can be partially removed. The above preferred simplified method can ensure that there is almost no impact on subsequent simulation calculations and process tests, thereby further improving the efficiency of simulation calculations and simulation parts design while ensuring accuracy, and saving materials and reducing manufacturing costs during process tests.

[0032] (6) In some preferred embodiments, for the linear elastic mechanics analysis of the pre-rotation process simulation, by selecting and setting appropriate initial conditions, boundary conditions and load application, material property definition, and the type and size of mesh division, it helps to ensure the accuracy, effectiveness and efficiency of the linear elastic mechanics analysis for the pre-rotation process simulation.

[0033] (7) In some preferred embodiments, in step S4, according to the specific inconsistency of the stress-strain distribution trend and order of magnitude, the rotation speed and the model are optimized to achieve consistency. Specifically, when optimizing the rotation speed, the parametric simulation function can be used to quickly find the rotation speed parameter that makes the stress-strain distribution of the simplified model of the disc forging consistent with the stress-strain distribution of the initial model. This rotation speed parameter is the "equivalent rotation speed", which ensures that the simplified model can accurately reflect the stress-strain behavior of the actual disc forging during the pre-rotation process, thereby improving the reliability of the simulation and the prediction accuracy.

[0034] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0036] Figure 1A schematic diagram of the flow chart of the simulation component design method provided by the present invention;

[0037] Figure 2 A schematic structural diagram of an initial model of a disc forging provided in an embodiment of the present invention;

[0038] Figure 3 A schematic diagram of the structure of a simplified model provided by an embodiment of the present invention;

[0039] Figure 4 The stress distribution diagrams of the initial model and simplified model of the disc forging provided in the embodiment of the present invention obtained after linear elastic mechanics analysis, wherein (a) is the stress distribution diagram of the initial model, and (b) is the stress distribution diagram of the simplified model;

[0040] Figure 5 The strain distribution diagrams of the initial model and simplified model of the disc forging provided in the embodiment of the present invention obtained after linear elastic mechanics analysis, wherein (a) is the strain distribution diagram of the initial model, and (b) is the strain distribution diagram of the simplified model;

[0041] Figure 6 A comparison diagram of the plastic strain of a simulation part (MN for short) and an actual disc forging part (DJ for short) after pre-rotation provided in an embodiment of the present invention;

[0042] Figure 7 The initial residual stress distribution diagrams of the initial model and simplified model of the disc forging provided in the embodiment of the present invention obtained after thermal-mechanical coupling analysis, wherein (a) is the initial residual stress distribution diagram of the initial model, and (b) is the initial residual stress distribution diagram of the simplified model. DETAILED DESCRIPTION

[0043] 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.

[0044] Simulation design refers to the creation of a small or scaled-down model to represent the actual part in engineering and scientific research. This design is used to simulate performance under actual working conditions in order to test and evaluate the effectiveness, safety and functionality of the design before investing a lot of resources in full-scale production or construction. Based on the above concept, the inventor believes that simulation design can be used for the internal stress regulation effect of the pre-rotation process of large high-temperature alloy disc forgings and the prediction and verification of the change in the mechanical properties of the material after rotation, so as to solve at least one of the problems of the existing simulation method for the pre-rotation process of large high-temperature alloy disc forgings, namely, there is a large gap between the simulation results and the actual situation, the simulation efficiency is low, and it is difficult to accurately evaluate the change in the mechanical properties of the material after pre-rotation. However, there is currently no relevant technical solution for how to design a suitable simulation model that can solve at least one of the above problems.

[0045] Based on this, the present invention provides a simulation part design method for simulating a disk forging pre-rotation process, the method comprising the following steps:

[0046] S1. Establish the initial model of the disc forging;

[0047] S2. Based on the stress-strain results of linear elastic mechanics analysis of the initial model, the structural features that have no obvious structural strength correlation in the initial model are eliminated; then the size is reduced to obtain a simplified model;

[0048] S3, performing a linear elastic mechanics analysis on the simplified model to obtain stress-strain results, and determining whether the stress-strain results of the linear elastic mechanics analysis of the initial model and the linear elastic mechanics analysis of the simplified model are consistent;

[0049] S4. Based on the judgment result of S3, if there is inconsistency, return to S3 to optimize the rotation speed in the linear elastic mechanics analysis, or return to S2 to adjust the simplified model and perform S3, through iterative optimization, until the stress-strain results of S2 and S3 are consistent, and the simplified model and rotation speed that can produce consistent stress-strain results are used as the simulation part model and process test rotation speed respectively;

[0050] S5. Based on the simulation part model of S4, a simulation part is manufactured and a pre-rotation test is performed at the process test rotation speed to verify the accuracy and reliability of the simulation part model and the simulation part in simulating the actual disc forging pre-rotation process.

[0051] Compared with the prior art, the present invention provides a simulation part design method for simulating the pre-rotation process of disc forgings, which realizes accurate and efficient simulation of the stress, strain and performance changes of actual disc forgings in the pre-rotation process. The "simulation part model + process test speed" determined by the method of the present invention can accurately and reliably predict the internal stress regulation effect of the actual disc forging after the pre-rotation process, thereby better guiding the optimization of process parameters and making more scientific and accurate process decisions, which in turn helps to improve the quality of large disc forgings of high-temperature alloys. Specifically, the present invention reasonably simplifies the structure of the initial model of the disc forging and performs size reduction based on the results of linear elastic mechanics analysis of the disc forging to obtain a simplified model; based on the comparison of the results of linear elastic mechanics analysis of the simplified model with the results of the initial model, the simplified model and / or the rotation speed are optimized to find a "simplified model" and "rotation speed" that can ensure the consistency of stress-strain distribution of the "initial model" and the "simplified model", and preliminarily determine them as the "simulation part model" and "process test rotation speed"; a pre-rotation test is carried out based on the "simulation part model" and the "process test rotation speed", and through experimental verification, it is further ensured that the results of the pre-rotation simulation and process test based on the "simulation part model" and the "process test rotation speed" are consistent with the results of the actual disc forging after pre-rotation. In other words, it is ensured that the difference between the results of the pre-rotation simulation and process test based on the "simulation part model + process test rotation speed" and the results of the actual disc forging after pre-rotation is very small. When simplifying the model, reasonable elimination of structural features and dimensional scaling can reduce calculations and improve the computational efficiency of pre-rotation computer simulation based on "simulation part model + process test speed". Compared with the existing simulation methods, the "simulation part model + process test speed" obtained based on the design method of the present invention is more accurate and the efficiency is significantly improved when simulating the actual disc forging pre-rotation process.

[0052] Preferably, in step S2, the size reduction ratio is controlled at 50-75%. By setting it in this way, by selecting a suitable size reduction ratio, the process feasibility and cost-effectiveness can be optimally balanced; it can be understood that if the size reduction ratio is too small (<50%), the required process test speed (equivalent speed) is too high, which may exceed the equipment capacity of the pre-rotation test and make it difficult to achieve, and if the size reduction ratio is too large (>75%), it will not achieve the purpose of saving raw materials, which will be unfavorable for achieving the optimal balance between process feasibility and cost-effectiveness. Exemplarily, the size reduction ratio is 55%, 60%, 65%, and 70%.

[0053] Further preferably, in step S2, the size reduction ratio also satisfies: a plurality of standard specimens for mechanical property testing can be taken out from the simulation part made based on the simulation part model in S4; step S5 also includes: after the pre-rotation test, a plurality of standard specimens are taken out from the simulation part, and the material mechanical properties of the standard specimens are obtained through mechanical property testing, and the changes in the material mechanical properties of the disc forging after the pre-rotation process are evaluated based on the material mechanical properties of the standard specimens.

[0054] It can be understood that since the "simulation model + process test speed" can simulate the physical phenomena (such as material deformation, stress state, etc.) of the actual disc forging during the pre-rotation process and after rotation with high precision, the mechanical property test results of the standard specimens taken from the simulation can be used as a reliable basis for evaluating the changes in the mechanical properties of the actual disc forging after pre-rotation. The simulation model and process test speed obtained based on the design method of the present invention can be used to perform pre-rotation tests, which can not only verify the accuracy and reliability of the simulation model, but also provide a simple and reliable evaluation method for the changes in the mechanical properties of the actual disc forging after the pre-rotation process, thereby providing a more comprehensive scientific basis for determining the optimal rotation process parameters. Based on "taking multiple standard specimens from the same simulation", it helps to ensure the consistency and comparability of the mechanical property test results and improve the reliability and statistical significance of the test data.

[0055] Exemplarily, the standard specimens include, but are not limited to, tensile, creep, and fatigue specimens to verify the effect of the pre-rotation process on the mechanical properties of the material.

[0056] In some possible designs, in step S1, the disc forging is a disc-shaft integrated forging with rotational symmetry, and its structural features are as follows: the disc forging includes a cylindrical body, one or more stepped inner holes are provided inside the cylindrical body, the outer wall of the cylindrical body vertically extends outward to form one or more disc-shaped structures, and the central axes of all the stepped inner holes coincide with the central axis of the cylindrical body. Furthermore, the central axes of all the disc-shaped structures coincide with the central axis of the cylindrical body.

[0057] Exemplarily, the disc forging includes a cylindrical body, a stepped inner hole is formed inside the cylindrical body, and the outer wall of the cylindrical body extends vertically outward to form a disc-shaped structure. The outer diameter of the cylindrical body on one side of the disc-shaped structure may be the same as or different from the outer diameter of the cylindrical body on the other side of the disc-shaped structure. Figure 2 In this embodiment, the outer diameter of the cylindrical body on the upper side of the disc-shaped structure is greater than the outer diameter of the cylindrical body on the lower side of the disc-shaped structure.

[0058] For the disc-shaft integrated forging with rotational symmetry, in step S1, the initial model is a two-dimensional axisymmetric geometric model. Since the above-mentioned structural characteristics of the disc forging have obvious axisymmetric characteristics, that is, they have rotational symmetry around a certain axis, the use of a two-dimensional axisymmetric geometric model for modeling can significantly reduce the amount of calculation and the number of grids, while maintaining sufficient accuracy to capture the key stress and strain distribution, so as to more efficiently perform subsequent simulation analysis and optimization of one or more of the disc forging structural characteristics, size reduction, and rotation speed.

[0059] Specifically, in step S1, a computer modeling software is used to establish an initial model of the disc forging; illustratively, the computer modeling software includes but is not limited to UG, Solidworks, and Inventor.

[0060] It should be noted that step S1 also includes: before establishing the initial model of the disc forging, extracting the structural features and corresponding dimensional parameters of the disc forging. For the disc forging, the structural features include but are not limited to the inner and outer diameters, height, inner hole step width, outer diameter thin wall structure thickness, chamfer, transition arc and inclination angle of the disc forging.

[0061] Based on the structural characteristics of the above disc forging, the structural features include: the outer diameter D of the cylindrical body c and inner diameter d c And the total height H c , the depth of each step inner hole is H1, H2, ... H i and widths W1, W2, ... W i , the outer diameter of each disc-shaped structure is D1, D2, ... D j and thickness T1, T2, ... T j , the distance between the center of each disk-shaped structure and the center of one end of the cylindrical body is L1, L2, ... L j , where i is the number of step inner holes and j is the number of disc-like structures. It can be understood that the "depth" refers to the vertical distance from the center of one end of the cylindrical body to the bottom of each step inner hole; the "width" refers to the radius difference between two adjacent step inner holes.

[0062] In some possible designs, the bottom of one or more stepped inner holes is not perpendicular to the axis of the cylindrical body, but is inclined to a certain extent, and the structural feature also includes: the inclination angle of the bottom of the one or more stepped inner holes relative to the axis of the cylindrical body. When the cylindrical body has different outer diameters on both sides of one or more disc-shaped structures, the outer diameter D of the cylindrical body is c Specifically including D c1 , D c2 , ...D cf, f is a natural number and satisfies f≤j+1, j is the number of disk-like structures.

[0063] For the disk-shaft integrated forging with rotational symmetry, preferably, in step S2, the main step of simplification includes: removing the thin-walled area above the step inner hole in the disk forging, and only retaining 5% to 15% of the thin-walled area along the axial direction near the step inner hole. Exemplarily, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% of the thin-walled area is retained.

[0064] Further preferably, the main step of simplifying further includes: removing the thick-walled area between the other end of the disc forging away from the thin-walled area and the adjacent disc-shaped structure, but retaining 50%-70% of the thick-walled area along the axial direction close to the adjacent disc-shaped structure. Exemplarily, 53%, 55%, 57%, 60%, 63%, 65%, 67% of the thick-walled area are retained.

[0065] It should be noted that for the disk-shaft integrated forging with rotational symmetry, the above-mentioned preferred simplified method can ensure that there is almost no impact on subsequent simulation calculations and process tests, thereby further improving the efficiency of simulation calculations and simulation parts design while ensuring accuracy, and saving materials and reducing manufacturing costs during process tests.

[0066] The "thin-walled area" in the present invention refers to the area located on the side of the stepped inner hole with the largest diameter and where the difference between the inner and outer diameters of the cylindrical body is the smallest, such as Figure 2 The "thick wall area" refers to the part of the cylindrical body located between the other end of the disc forging away from the thin wall area and the adjacent disc-shaped structure, such as Figure 2 Middle section B.

[0067] Specifically, the linear elastic mechanics analysis includes the following steps:

[0068] (1) Model preparation: The model preparation mainly includes: importing the geometric model to be analyzed;

[0069] (2) Material property definition; the material property definition includes: defining Young's modulus as 210-220 GPa, Poisson's ratio as 0.25-0.35, room temperature yield strength as 1100-1150 MPa, and room temperature tensile strength as 1500-1550 MPa;

[0070] (3) initial condition setting; the initial condition setting includes: initial stress is set to zero, initial temperature is set to room temperature;

[0071] (4) Mesh division; the mesh division includes: selecting a two-dimensional quadrilateral unit mesh as the mesh type, the mesh size at the right angles of the model transition is 0.1 mm to 0.5 mm, and the mesh size of the remaining parts is 1 mm to 2 mm.

[0072] (5) Boundary conditions and load application; the boundary conditions and load application include: fixing the radial displacement of the upper and lower end surfaces of the model, and then applying a rotational speed load to the entire model.

[0073] The above parameter settings help ensure the accuracy, effectiveness and efficiency of linear elastic mechanics analysis for pre-rotation process simulation. Specifically, (a) defining appropriate material properties such as Young's modulus, Poisson's ratio, yield strength and tensile strength provides an accurate description of material behavior for the simulation, which is crucial for predicting the stress-strain response of the model in the pre-rotation process. (b) setting the initial stress to zero and the initial temperature to room temperature simplifies the starting state of the problem, avoids unnecessary initial deviations, and helps to more accurately simulate the physical phenomena of the disc forging in the pre-rotation process (e.g., deformation of the material, stress state, etc.). (c) by fixing the radial displacement of the upper and lower end faces of the model and applying a rotational load as a whole, the working conditions of the disc forging in the actual pre-rotation process can be simulated, ensuring the practical significance and application value of the simulation results. (d) using a smaller grid size (e.g., 0.1 mm to 0.5 mm) in key areas can capture stress concentration, while using a larger grid size (e.g., 1 mm to 2 mm) in other areas can reduce the amount of calculation. This adaptive grid division balances the computational cost and simulation accuracy.

[0074] It should be noted that the specific parameters and conditions for linear elastic mechanics analysis of the initial model and the simplified model are basically the same, and the rotation speeds can be the same or different.

[0075] It should be noted that step S4 specifically includes the following steps:

[0076] S41. If the distribution trend of stress-strain results is consistent but the order of magnitude is inconsistent, use the parametric simulation function in the finite element analysis software to optimize the rotation speed of the linear elastic mechanics analysis in S3 until the equivalent rotation speed is determined, which can make the distribution trend and order of magnitude of the stress-strain results of S2 and S3 consistent;

[0077] S42. If the distribution trends of the stress-strain results are inconsistent, return to S2, adjust the structural features and / or dimensional scaling that have no obvious structural strength correlation, and then proceed to S3.

[0078] Specifically, in step S41, the main steps of "using the parametric simulation function in the finite element analysis software to optimize the rotational speed of the linear elastic mechanics analysis in S3" include: using the parametric simulation function in the finite element analysis software, taking the rotational speed as a variable, and setting other parameters and conditions to remain unchanged, and finding an equivalent rotational speed that is consistent with the distribution trend and order of magnitude of the stress and strain results of S2 by batch calculation of different rotational speeds and outputting the stress and strain results corresponding to all rotational speeds.

[0079] It can be understood that in step S41, the parametric simulation function can be used to quickly find the speed parameter that makes the stress-strain distribution of the simplified model of the disc forging consistent with the stress-strain distribution of the initial model of the disc forging. This speed parameter is the "equivalent speed", which ensures that the simplified model can accurately reflect the stress-strain behavior of the actual disc forging during the pre-rotation process, thereby improving the reliability and prediction accuracy of the simulation. The "equivalent speed" plays a vital role in the accurate simulation of the simplified model and subsequent process tests, and is an important bridge connecting simulation and actual production.

[0080] In some possible implementations, step S2 also includes: performing a thermomechanical coupling analysis on the initial model to simulate the initial residual stress introduced by the actual disc forging during the forging and heat treatment process; step S3 also includes: performing a thermomechanical coupling analysis on the simplified model to obtain the initial residual stress introduced by the simplified model during the forging and heat treatment process; by comparison, the initial residual stresses of the two are consistent, further enhancing confidence in the simplified model; the simulation model obtained by the design method of the present invention can not only accurately, reliably and efficiently simulate the stress-strain behavior and performance changes in the pre-rotation process, but also accurately and efficiently predict the distribution of initial residual stress after manufacturing and heat treatment, that is, it has the ability to accurately simulate the entire actual process of the disc forging. The simulation model obtained by the design method of the present invention can accurately simulate the entire production process of the disc forging (including forging, heat treatment and pre-rotation processes), so as to better control and manage the stress and strain conditions at each stage, and provide reliable data for optimizing process parameters and operating conditions. Accurate simulation can reduce the number of trial and error, reduce material waste and production costs, and improve production efficiency.

[0081] It can be understood that “initial residual stress is consistent” includes: the distribution trend and order of magnitude of the initial residual stress of the initial model are completely consistent with the distribution trend and order of magnitude of the simplified model, or the difference is within the acceptable range of design requirements.

[0082] Specifically, the thermal-mechanical coupling analysis includes the following steps:

[0083] (a) Model preparation; the model preparation mainly includes: importing the geometric model to be analyzed;

[0084] (b) Material property definition; the material property definition includes: elastic modulus, Poisson's ratio, specific heat capacity, thermal conductivity, linear expansion coefficient, interface heat transfer coefficient, and stress-strain curves at different temperatures from room temperature to T1 of the material of the same material as the actual disc forging, T1 is 1100-1300°C, and T1 corresponds to the preset temperature of the solution aging heat treatment of the actual disc forging; the above material property definition parameters can be obtained by measuring the material, and the material is the same as the material of the actual disc forging; the temperature interval from room temperature to T1 can be selected according to the speed of change of the material properties in this interval, for example: the temperature interval is 5°C, 10°C, 20°C, 50°C, and 100°C.

[0085] (c) initial condition setting; the initial condition setting includes: the initial temperature is set to T1;

[0086] (d) Mesh division; the mesh division includes: selecting a two-dimensional quadrilateral unit mesh as the mesh type, the mesh size at the right angles of the model transition is 0.1 mm to 0.5 mm, and the mesh size of the remaining parts is 1 mm to 2 mm.

[0087] (e) Boundary conditions and load application; the boundary conditions include: fixing the upper and lower end faces of the model in the axial and circumferential directions, being free in the radial direction, and not setting initial stress.

[0088] The load application is divided into two steps: ① thermal calculation process: the ambient temperature is set to room temperature, the disc forging temperature is T1, the interface heat transfer coefficient is set, and the time is set to t1=2400-4800s; ② force calculation process: the initial temperature distribution and the terminal temperature distribution are brought into the thermal calculation.

[0089] (6) Thermal coupling settings: ① Thermal calculation process: set 900-1100 sub-steps, total time t1; ② Force calculation process: static calculation, set 1 to 5 sub-steps.

[0090] Specifically, in step S5, the specific methods of "verifying the accuracy and reliability of the simulation model and the simulation for simulating the actual disc forging pre-rotation process" include but are not limited to the following:

[0091] Method 1: Comparative analysis of deformation:

[0092] After the pre-rotation test, the simulated part is subjected to detailed geometric measurement to obtain its deformation data; similarly, the actual disc forging is subjected to the pre-rotation process and its deformation is measured; the deformation data of the simulated part and the actual disc forging are compared to evaluate the consistency between the two; if the deformation data match well, it means that the simulated part model and the simulated part made based on the simulated part model are accurate and reliable for simulating the actual disc forging pre-rotation process.

[0093] Method 2: Measurement and comparison of residual stress:

[0094] After the pre-rotation test, the residual stress of the simulated part is measured using techniques such as X-ray diffraction, neutron diffraction or profilometry; similarly, the residual stress of the actual disc forging is measured after the pre-rotation process; the residual stress data of the simulated part and the actual disc forging are compared to check the consistency of the stress value and the distribution pattern; if the stress value and the distribution pattern match well, it means that the simulated part model and the simulated part made based on the simulated part model are accurate and reliable for simulating the pre-rotation process of the actual disc forging.

[0095] Specifically, in method 2, the profile method is a technology used to measure the internal residual stress of metal material disk / ring forgings. The specific operation and standard requirements can be based on any one of the following two standards: (1) T / ZSA 168-2023 standard "Profile method for measuring residual stress of metal material disk / ring forgings"; (2) T / CSTM 00347-2020 standard "Profile method for measuring residual stress of metal material disk / ring forgings".

[0096] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments.

[0097] Example 1-1:

[0098] This embodiment provides a simulation part design method for simulating a disk forging pre-rotation process, the method comprising the following steps:

[0099] S1. Establish the initial model of the disc forging;

[0100] The disc forging is an integrated forging of the disc and shaft of an aircraft engine. The extracted structural features and corresponding dimensional parameters are as follows: The inner diameter d of the cylindrical body c = 108mm, the total height H of the cylindrical body c =370mm, the depth of the inner hole of the step H1 = 230mm, the width of the inner hole of the step W1 = 38.5mm, the outer diameter of the disc-shaped structure D1 = 460mm, the thickness of the disc-shaped structure T1 = 48mm, the distance between the center of the disc-shaped structure and the center of one end of the cylindrical body L1 = 301mm, the outer diameter of the cylindrical body above the disc-shaped structure D c1 = 268 mm, the outer diameter D of the cylindrical body below the disc-shaped structure c2 =232mm.

[0101] According to the above structural features and size parameters, the UG software is used to create a two-dimensional axisymmetric geometric model of the disc forging, such as Figure 2 shown.

[0102] S2. Using ANSYS analysis software, a linear elastic mechanics analysis is performed on the initial model of the disc forging to obtain the stress distribution and strain distribution of the initial model after pre-rotation; the linear elastic mechanics analysis specifically includes the following steps:

[0103] (1) Model preparation: Import the two-dimensional axisymmetric geometric model established in step S1, such as Figure 2 ;

[0104] (2) Material property definition: Young's modulus is defined as 217 GPa, Poisson's ratio is defined as 0.3, room temperature yield strength is defined as 1130 MPa, and room temperature tensile strength is defined as 1530 MPa;

[0105] (3) Initial condition setting: initial stress is set to zero, initial temperature is set to 25°C;

[0106] (4) Mesh division: The mesh type is a two-dimensional quadrilateral unit mesh. The mesh size at the transition right angle of the model is 0.3 mm, and the mesh size of the rest is 1 mm.

[0107] (5) Boundary conditions and load application: The radial displacements of the upper and lower end surfaces of the model are fixed, and then a rotation speed load is applied to the entire model at a speed of 24,000 rpm;

[0108] (6) Use the direct solver to output the stress distribution diagram and strain distribution diagram of the initial model, see Figure 4 (a) and Figure 5 (a); from Figure 4 (a) and Figure 5 It can be seen from (a) that the pre-rotation process has no obvious effect on the stress and strain distribution of the thin-walled area above the step inner hole and the lower end of the initial model. It can be eliminated as a structural feature with no obvious structural strength correlation. Specifically, the thin-walled area above the step inner hole in the initial model is eliminated, and only the 6% thin-walled area along the axial direction near the step inner hole is retained. In addition, the thick-walled area between the lower end of the initial model and the lower surface of the disc-shaped structure is eliminated, but the 56% thick-walled area along the axial direction below the disc-shaped structure is retained. Then, each side of the eliminated model is scaled down by 75% to obtain a simplified model, see Figure 3 ;

[0109] S3, performing linear elastic mechanics analysis on the simplified model to obtain stress distribution and strain distribution of the simplified model after pre-rotation, and determining whether the stress and strain results of the linear elastic mechanics analysis of the initial model and the linear elastic mechanics analysis of the simplified model are consistent;

[0110] S4. By comparison, it is found that the distribution trend of stress and strain results is consistent, but the order of magnitude is inconsistent. A parameterized table is created in ANSYS to list all different speed values ​​that need to be simulated. The parameterized simulation function module in ANSYS (such as the English name DesignXplorer) is used to take the speed as a variable, and other parameters and conditions are set unchanged. By batch calculating different speeds and outputting the stress and strain results corresponding to all speeds, the equivalent speed of 32600rpm is found to be consistent with the distribution trend and order of magnitude of the stress and strain results of S2. The stress distribution and strain distribution obtained by linear elastic mechanics analysis based on the simplified model of S3 and the equivalent speed are as follows: Figure 4 (b) and Figure 5 (b)

[0111] By comparison, it can be seen that the distribution trend and order of magnitude of the stress-strain distribution of the initial model are consistent with those of the simplified model. Figure 4 and Figure 5 It can be seen that the stress distribution of the initial model and the simplified model at their respective predetermined rotation speeds (the initial model speed is 24000rpm, and the simplified model speed is 32600rpm) shows that after pre-rotation, the stress at the corners of the upper and lower end faces of the transition zone of the disc-shaped structure is relatively large (red part), and the stress range in this area is 1500-1700MPa; the strain distribution shows that the equivalent plastic strain in the middle of the inner hole core of the disc-shaped structure is relatively large, and the equivalent plastic strain in this area ranges from 0.55% to 0.80%, and extends radially to the inside of the disc-shaped structure;

[0112] The simplified model of S3 and the equivalent speed of 32600 rpm were used as the simulation model and process test speed respectively.

[0113] S5. A simulated part is manufactured based on the simulated part model of S4 and a pre-rotation test is performed at 32600 rpm. After the pre-rotation test, a detailed geometric measurement is performed on the simulated part to obtain its deformation data. Similarly, the actual disc forging is subjected to a pre-rotation process at a rotation speed of 24000 rpm and its deformation is measured. The deformation data of the simulated part and the actual disc forging are compared, such as Figure 6 As shown, by comparison, the deformation data of the two are well matched, indicating that the simulation model and the simulation part are accurate and reliable for simulating the actual disc forging pre-rotation process.

[0114] In addition, after pre-rotation, the residual stresses of the simulated part and the actual disc forging were measured and compared by the contour method. Similarly, the stress values ​​and distribution patterns of the two matched well, which also shows that the simulated part model and the simulated part are accurate and reliable for simulating the pre-rotation process of the actual disc forging.

[0115] Embodiment 1-2:

[0116] This embodiment adds thermal-mechanical coupling analysis on the basis of embodiment 1-1 to further verify the simulation accuracy of the simplified model for the initial residual stress introduced by forging and heat treatment of disc forgings; the details are as follows:

[0117] Step S2 also includes: using ANSYS analysis software to perform a thermal-mechanical coupling analysis on the initial model of the disc forging to simulate the initial residual stress introduced by the disc forging during the forging and heat treatment process; the thermal-mechanical coupling analysis specifically includes the following steps:

[0118] a) Model preparation: Import the two-dimensional axisymmetric geometric model established in step S1, such as Figure 2 ;

[0119] b) Definition of material properties: By measuring the elastic modulus, Poisson's ratio, specific heat capacity, thermal conductivity, linear expansion coefficient, interface heat transfer coefficient of the same material as the disc forging at different temperatures from room temperature to 1200°C, as well as the stress-strain curves at different temperatures, the measured results are input into the ANSYS analysis software;

[0120] c) Initial condition setting: the initial temperature is set to 1200°C;

[0121] d) Mesh division: The mesh type is a two-dimensional quadrilateral unit mesh, the mesh size at the transition right angles of the model is 0.3 mm, and the mesh size of the rest is 1 mm.

[0122] e) Boundary conditions and load application; the boundary conditions include: the upper and lower end faces of the model are fixed axially and circumferentially, radially free, and no initial stress is set. The load application is divided into two steps: ① Thermal calculation process: the ambient temperature is set to 25°C, the disk forging temperature is 1200°C, the interface heat transfer coefficient is set based on the measured results, and the time is set to t1=3600s; ② Force calculation process: bring in the initial temperature distribution and the terminal temperature distribution of the thermal calculation.

[0123] f) Thermal coupling settings: ① Thermal calculation process: set 1000 substeps, total time 3600s; ② Force calculation process: static calculation, set 1 substep;

[0124] g) Use the thermal analysis solver and the statics solver to complete the thermal calculation process and the force calculation process respectively, and output the results, such as Figure 7 (a)

[0125] Step S3 also includes: using steps and parameter settings similar to those in (a) to (g) above to perform thermal-mechanical coupling analysis on the simplified model, and obtaining the following: Figure 7 (b) shows the results; by comparison, it can be seen that the distribution of initial residual stress of the full-size initial model and the simplified model is consistent, and Figure 7 It can be seen that the initial model and simplified model of the disc forging have the largest residual stress in the center transition zone of the cross section under the established production process. The specific calculated value is 500-550MPa, which is basically consistent with the initial residual stress of the actual disc forging under the established production process.

[0126] It can be seen that the simulation part model obtained by the design method of the embodiment of the present invention is suitable. It can not only accurately simulate the performance of the disc forging in actual manufacturing and heat treatment (for example, the initial residual stress distribution), but also accurately simulate the performance of the disc forging in the actual pre-rotation process (for example, the deformation and stress state of the material) through the "simulation part model + equivalent rotation speed". The simulation part is manufactured based on the simulation part model for pre-rotation test, and multiple standard specimens are directly taken out from the simulation part after pre-rotation for mechanical property testing. The mechanical properties of the disc forging after the actual pre-rotation process can also be comprehensively evaluated. The data provided by the accurate process simulation and mechanical property testing can better determine the optimal heat treatment and pre-rotation process parameters, thereby improving production efficiency and product quality, while reducing costs and saving materials.

[0127] Examples 1-3

[0128] The difference between this embodiment and embodiment 1-1 is that: in step S2, the thin-walled area above the step inner hole in the initial model is eliminated, and only the 3% thin-walled area along the axial direction close to the step inner hole is retained, and the remaining steps and parameters are similar to those of embodiment 1-1;

[0129] Since this embodiment does not adopt the preferred simplified method provided by the present invention (retaining a 5% to 15% thin-walled area along the axial direction near the step inner hole), in step S4 of this embodiment, it is found through comparison that the distribution trend of the stress-strain results is basically the same, and the difference in order of magnitude is larger than that of Example 1-1.

[0130] Examples 1-4

[0131] The difference between this embodiment and embodiment 1-1 is that: in step S2, the thick-walled area between the lower end of the initial model and the lower surface of the disc-shaped structure is eliminated, but the 40% thick-walled area along the axial direction below the disc-shaped structure is retained, and the remaining steps and parameters are similar to those of embodiment 1-1;

[0132] Since this embodiment does not adopt the preferred simplified method provided by the present invention (retaining the 50%-70% thick wall area along the axial direction close to the adjacent disc-shaped structure), in step S4 of this embodiment, it is found through comparison that the distribution trend of the stress-strain results is basically the same, and the difference in order of magnitude is larger than that of Example 1-1.

[0133] 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 designing a simulation part for simulating a pre-rotation process of a disc forging, characterized in that: The method comprises the following steps: S1. Establish the initial model of the disc forging; S2. Based on the stress-strain results of linear elastic mechanics analysis of the initial model, the structural features that have no obvious structural strength correlation in the initial model are eliminated; then the size is reduced to obtain a simplified model; S3, performing a linear elastic mechanics analysis on the simplified model to obtain stress-strain results, and determining whether the stress-strain results of the linear elastic mechanics analysis of the initial model and the linear elastic mechanics analysis of the simplified model are consistent; S4. Based on the judgment result of S3, if there is inconsistency, return to S3 to optimize the rotation speed in the linear elastic mechanics analysis, or return to S2 to adjust the simplified model and perform S3, through iterative optimization, until the stress-strain results of S2 and S3 are consistent, and the simplified model and rotation speed that can produce consistent stress-strain results are used as the simulation part model and process test rotation speed respectively; S5. Based on the simulation part model of S4, a simulation part is manufactured and a pre-rotation test is performed at the process test rotation speed to verify the accuracy and reliability of the simulation part model and the simulation part in simulating the actual disc forging pre-rotation process.

2. The design method according to claim 1, characterized in that: In step S2, the size reduction ratio is controlled within a range of 50-75%.

3. The design method according to claim 2, characterized in that: In step S2, the size reduction ratio also satisfies: a plurality of standard specimens for mechanical property testing can be taken out from the simulation part made based on the simulation part model in S4; Step S5 also includes: after the pre-rotation test, taking out a plurality of standard specimens from the simulation part, obtaining the material mechanical properties of the standard specimens through mechanical property testing, and evaluating the material mechanical property changes of the disc forging after the pre-rotation process based on the material mechanical properties of the standard specimens.

4. The design method according to claim 1, characterized in that: In step S1, the disc forging is a disc-shaft integrated forging with rotational symmetry, including a cylindrical body, one or more stepped inner holes are provided inside the cylindrical body, and the outer wall of the cylindrical body extends vertically outward to form one or more disc-shaped structures, and the central axes of all the stepped inner holes coincide with the central axis of the cylindrical body.

5. The design method according to claim 4, characterized in that: In step S1, the initial model is a two-dimensional axisymmetric geometric model.

6. The design method according to claim 4, characterized in that: In step S2, the main steps of simplification include: removing the thin-walled area above the step inner hole in the disc forging, and only retaining the axially 5% to 15% thin-walled area close to the step inner hole.

7. The design method according to claim 6, characterized in that: The main step of simplification also includes: removing the thick wall area between the other end of the disc forging away from the thin wall area and the adjacent disc-shaped structure, but retaining the axial 50%-70% thick wall area close to the adjacent disc-shaped structure.

8. The design method according to claim 1, characterized in that: The linear elastic mechanics analysis includes: model preparation, initial condition setting, boundary conditions and load application; wherein the initial condition setting includes: initial stress is set to zero, initial temperature is set to room temperature; The boundary conditions and load application include: fixing the radial displacement of the upper and lower end surfaces of the model, and then applying a rotation speed load to the entire model.

9. The design method according to claim 4, characterized in that: The linear elastic mechanics analysis includes: material property definition and mesh division; wherein the material property definition includes: defining Young's modulus as 210-220 GPa, Poisson's ratio as 0.25-0.35, room temperature yield strength as 1100-1150 MPa, and room temperature tensile strength as 1500-1550 MPa; and / or, The grid division includes: selecting a two-dimensional quadrilateral unit grid as the grid type, the grid size at the transition right angle of the model is 0.1 mm to 0.5 mm, and the grid size of the remaining parts is 1 mm to 2 mm.

10. The design method according to claim 1, characterized in that: Step S4 specifically includes the following steps: S41. If the distribution trend of stress-strain results is consistent but the order of magnitude is inconsistent, use the parametric simulation function in the finite element analysis software to optimize the rotation speed of the linear elastic mechanics analysis in S3 until the equivalent rotation speed is determined, which can make the distribution trend and order of magnitude of the stress-strain results of S2 and S3 consistent; S42. If the distribution trends of the stress-strain results are inconsistent, return to S2, adjust the structural features and / or dimensional scaling that have no obvious structural strength correlation, and then proceed to S3.

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