Workpiece machining method and workpiece machining system

Abstract

The invention discloses a workpiece machining method and a workpiece machining system.The workpiece machining method comprises the steps that a rigid weak area of a target workpiece is obtained, and a profiling supporting structure model is constructed based on geometrical characteristics of the rigid weak area; processing a workpiece semi-finished product, wherein the thickness of the workpiece semi-finished product in the rigid weak area is greater than that of the target workpiece in the rigid weak area; preparing a supporting structure based on the profiling supporting structure model; and under rigidity compensation of the supporting structure, subtractive machining is carried out on the workpiece semi-finished product, and a target workpiece is obtained. According to the method, the problems of geometric accuracy instability and surface quality degradation caused by insufficient rigidity in the machining process of the complex weak-rigidity workpiece can be solved, and the stability in the machining process is ensured and the machining accuracy and the surface quality are improved by quickly generating the supporting structure and enhancing the rigidity of the workpiece.

Description

Technical Field

[0001] The present invention belongs to the technical field of workpiece processing, and particularly relates to a workpiece processing method and a workpiece processing system. Background Art

[0002] In the field of processing complex and weakly rigid workpieces, due to the insufficient structural rigidity of the workpieces themselves, technical bottlenecks such as geometric accuracy instability and surface quality deterioration are commonly faced during the processing. To break through this predicament, the current industry mainly adopts three types of technical routes:

[0003] 1. Copying fixture technology: By customizing a special support structure that highly matches the shape of the workpiece, although this solution can provide local rigidity enhancement, it has significant limitations in practical applications. Its technical adaptability is restricted by the geometric features of the workpiece, and it is difficult to effectively clamp workpieces such as impellers and disk-shaped workpieces with undercut structures or complex irregular contours. Moreover, a matching fixture needs to be newly developed for each new model workpiece, increasing production costs and production cycles.

[0004] 2. Filling material support technology: Using media such as gypsum and polymer composites to fill the cavities of workpieces. Although this solution has a certain degree of shape adaptability, there is a risk of support failure under high-speed machining conditions. During the processing, the alternating stress caused by cutting vibration is likely to cause the filling material to break and fall off. A more prominent problem is that a large amount of man-hours are required for filling and removing residual materials in the pre- and post-processing links, extending the production cycle.

[0005] 3. Automated flexible fixture technology: Achieving dynamic clamping through a multi-degree-of-freedom adjustment mechanism, which theoretically has the advantage of adapting to workpieces of different shapes. However, in practical applications, this technology faces significant efficiency constraints: Each time the workpiece type and processing program are changed, a large amount of time is required for fine debugging of clamping parameters. When the structural differences of the workpieces are large, it is often necessary to re-plan the clamping scheme. Such repeated adjustments result in a large proportion of the technical preparation link in the overall processing flow, inevitably extending the production cycle.

[0006] Although the existing technical systems provide solutions in different dimensions, they have not effectively balanced the contradictions among processing quality, production efficiency, and cost control.

[0007] Therefore, in view of the above technical problems, it is necessary to provide a workpiece processing method and a workpiece processing system. Summary of the Invention

[0008] The object of the present invention is to provide a workpiece processing method and a workpiece processing system, which can solve the problems of geometric accuracy instability and surface quality deterioration caused by insufficient rigidity during the processing of complex and weakly rigid workpieces. By quickly generating a support structure, the rigidity of the workpiece is enhanced, thereby ensuring the stability during the processing and improving the processing accuracy and surface quality.

[0009] To achieve the above object, the technical solution provided by a specific embodiment of the present invention is as follows:

[0010] A workpiece processing method, the workpiece processing method comprising:

[0011] Obtain the rigid weak area of the target workpiece, and construct a profiling support structure model based on the geometric features of the rigid weak area;

[0012] Machine a workpiece semi-finished product, the thickness of the workpiece semi-finished product in the rigid weak area being greater than the thickness of the target workpiece in the rigid weak area;

[0013] Prepare a support structure based on the profiling support structure model;

[0014] Under the rigid compensation of the support structure, perform subtractive machining on the workpiece semi-finished product to obtain a target workpiece.

[0015] In one or more embodiments of the present invention, obtaining the rigid weak area of the target workpiece includes:

[0016] Perform finite element analysis on the target workpiece, and define the area with the maximum deformation of the target workpiece as the rigid weak area of the target workpiece.

[0017] In one or more embodiments of the present invention, the profiling support structure model includes a linear support model, a grid support model, a tree support model, a block support model, a column support model, a cone support model, and a trapezoid support model; and / or, the support structure includes a fully wrapped support structure, a semi-wrapped support structure, and an embedded support structure.

[0018] In one or more embodiments of the present invention, the set thickness of the profiling support structure model is positively correlated with the vibration amplitude of the target workpiece in the rigid weak area.

[0019] In one or more embodiments of the present invention, the workpiece processing method includes: preparing a support structure by 3D printing.

[0020] In one or more embodiments of the present invention, the printing material for the 3D printing includes ethylene-vinyl acetate copolymer; and / or, the 3D printing includes fused deposition modeling printing.

[0021] In one or more embodiments of the present invention, based on the profiling support structure model, 3D printing is performed on the rigid weak area of the semi-finished workpiece to obtain a support structure, and the size of the support structure matches the size of the rigid weak area; and / or,

[0022] Based on the profiling support structure model, 3D printing is performed on the tooling surface to obtain a support structure, and the size of the support structure matches the size of the rigid weak area.

[0023] In one or more embodiments of the present invention, subtractive machining is performed on the semi-finished workpiece to reduce the thickness of the semi-finished workpiece in the rigid weak area, and the support structure is synchronously removed to obtain a target workpiece.

[0024] In one or more embodiments of the present invention, the workpiece processing method further includes:

[0025] Preparing the support structure and performing subtractive machining based on the same processing equipment, and the coordinate system in the subtractive machining process coincides with the coordinate system in the process of preparing the support structure.

[0026] In one or more embodiments of the present invention, the target workpiece includes a blisk, the blisk includes a disk and a plurality of first blades arranged at intervals along the circumferential direction of the disk on the outer side wall of the disk, the first blade includes a first outer surface and a second outer surface arranged opposite to each other, and the rigid weak area of the blisk includes the first blade;

[0027] The workpiece processing method further includes:

[0028] Machining a blisk semi-finished product, and the thickness of the first blade of the blisk semi-finished product is greater than the thickness of the first blade of the target blisk;

[0029] Preparing a first support structure on the first outer surface of the first blade of the blisk semi-finished product, and preparing a second support structure on the second outer surface of the first blade of the blisk semi-finished product, the first support structure fits the first outer surface of the first blade, and the second support structure fits the second outer surface of the first blade.

[0030] In one or more embodiments of the present invention, the target workpiece includes an impeller, the impeller includes a hub plate and a plurality of second blades arranged at intervals along the circumferential direction of the hub plate on the outer side wall of the hub plate, the second blade includes a third outer surface and a fourth outer surface arranged opposite to each other, and the rigid weak area of the impeller includes the second blade;

[0031] The workpiece processing method further includes:

[0032] Machining an impeller semi-finished product, and the thickness of the second blade of the impeller semi-finished product is greater than the thickness of the second blade of the target impeller;

[0033] Prepare a support structure between the third outer surface of the second blade of the semi-finished impeller, the outer side wall of the hub plate, and the fourth outer surface of the adjacent second blade, and the support structure fits the third outer surface of the second blade, the outer side wall of the hub plate, and the fourth outer surface of the adjacent second blade.

[0034] In one or more embodiments of the present invention, the target workpiece includes a housing-type workpiece, the housing-type workpiece includes a housing, an inner cavity is formed on one side of the housing, and the rigid weak area of the housing-type workpiece includes the housing;

[0035] The workpiece processing method further includes:

[0036] Machine a semi-finished housing-type workpiece, and the thickness of the housing of the semi-finished housing-type workpiece is greater than the thickness of the target housing-type workpiece;

[0037] Prepare a support structure on the inner wall of the inner cavity or the surface of the tooling, and the support structure matches the size of the inner wall of the inner cavity.

[0038] The technical solution provided by another specific embodiment of the present invention is as follows:

[0039] A workpiece processing system includes:

[0040] A model construction module for obtaining the rigid weak area of the target workpiece and constructing a profiling support structure model based on the geometric features of the rigid weak area;

[0041] A first processing module for processing a semi-finished workpiece, and the thickness of the semi-finished workpiece in the rigid weak area is greater than the thickness of the target workpiece in the rigid weak area;

[0042] A support structure preparation module for preparing a support structure based on the profiling support structure model;

[0043] A second processing module for performing subtractive machining on the semi-finished workpiece under the rigid compensation of the support structure to obtain the target workpiece.

[0044] Compared with the prior art, the workpiece processing method and workpiece processing system of the present invention provide rigid compensation for the rigid weak area of the workpiece by preparing a support structure adaptable to workpieces of any complex shape, thereby ensuring the stability during the processing, improving the processing accuracy and surface quality, without the need for additional customized fixtures, and without additional chemical cleaning or physical cleaning steps;

[0045] The present invention solves the problems of geometric accuracy instability and surface quality deterioration caused by insufficient rigidity during the processing of complex weak-rigid workpieces at a low cost, and effectively balances the processing quality, production efficiency, and cost control;

[0046] The present invention can perform intelligent printing through a numerical control system without increasing labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0048] Figure 1 It is a flowchart of a workpiece processing method in the present invention;

[0049] Figure 2 It is a structural block diagram of a workpiece processing system in the present invention;

[0050] Figure 3a It is a schematic structural diagram of a blisk in Embodiment 1 of the present invention;

[0051] Figure 3b and Figure 3c It is a schematic diagram of a profiling support structure model in Embodiment 1 of the present invention;

[0052] Figure 3d and Figure 3e It is a schematic diagram of the support structure of the blisk in Embodiment 1 of the present invention;

[0053] Figure 4a It is a schematic structural diagram of an impeller in Embodiment 2 of the present invention;

[0054] Figure 4b It is a schematic diagram of the support structure of the impeller in Embodiment 2 of the present invention;

[0055] Figure 5a It is a schematic structural diagram of a housing workpiece in Embodiment 3 of the present invention;

[0056] Figure 5b It is a bottom view of the housing workpiece in Embodiment 3 of the present invention;

[0057] Figures 6a to 6d It is a schematic diagram of the processing flow of the housing workpiece in Embodiment 3 of the present invention; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0058] To enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0059] Unless otherwise clearly stated, in the whole specification and claims, the term "comprising" or its variations such as "including" or "having" etc. will be understood to include the stated elements or components, without excluding other elements or other components.

[0060] "Coupled" or "connected" or "linked" in the specification includes both direct connection and indirect connection. Indirect connection is a connection through an intermediate medium, such as a connection through an electrical conduction medium, which may have parasitic inductance or parasitic capacitance; indirect connection may also include a connection through other active or passive devices on the basis of achieving the same or similar functional purposes, such as a connection through circuits or components such as switches, follower circuits, etc. Additionally, in the present invention, words such as "first", "second", etc. are mainly used to distinguish one technical feature from another technical feature, and do not necessarily require or imply that there is a certain actual relationship, quantity, or order between these technical features.

[0061] In the detailed description of the specification, reference is made to the accompanying drawings that form a part of it, where the same reference numerals always represent the same components, and which are shown by way of exemplary embodiments that can be implemented. It should be understood that other embodiments can be utilized without departing from the scope of the present application, and structural or logical changes can be made. Therefore, the following detailed description should not be regarded as limiting.

[0062] The various operations in the specification can be described as a plurality of discrete actions or operations in the order that is most helpful for understanding the claimed subject matter. However, the described order should not be construed as implying that these operations must be order-related. Specifically, these operations may not be performed in the order presented. The described operations can be performed in an order different from the described embodiments. Various additional operations can be performed in additional embodiments and / or the described operations can be omitted.

[0063] For the purposes of the present application, the phrase "A and / or B" means (A), (B), or (A and B). For the purposes of the present application, the phrase "A, B, and / or C" means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C).

[0064] Various components and devices may be referred to or shown in the singular in this document (e.g., "MOS transistor", "transistor", "switch", etc.), but this is merely for convenience of discussion, and any element referred to in the singular may include a plurality of such elements in accordance with the teachings herein.

[0065] The specification describes the use of the phrases "in this embodiment" or "in other embodiments" or "in some embodiments", which may each refer to one or more of the same or different embodiments. In addition, the terms "comprising", "including", "having", etc. used with respect to the embodiments of this application are synonymous.

[0066] It should be noted that in the prior art, subtractive machining is usually performed on complex and weakly rigid workpieces. The main processes of subtractive machining include:

[0067] First rough machining: quickly remove the surplus material in the blank;

[0068] Semi-finishing machining: prepare a workpiece semi-finished product with a preliminary target workpiece shape, where a finishing allowance is reserved for the workpiece semi-finished product;

[0069] First finishing machining: complete the workpiece forming using carbide cutting tools and remove the finishing allowance;

[0070] Second finishing machining: remove the remaining residual allowance in the remaining areas.

[0071] It can be understood that during the finishing process of complex and weakly rigid workpieces, problems such as geometric accuracy instability and surface quality deterioration are likely to occur due to insufficient rigidity.

[0072] As Figure 1 shown, the present invention discloses a workpiece processing method, and the method includes:

[0073] S10, obtain the rigidly weak area of the target workpiece, and construct a profiling support structure model based on the geometric features of the rigidly weak area;

[0074] S20, machine the workpiece semi-finished product, and the thickness of the workpiece semi-finished product in the rigidly weak area is greater than the thickness of the target workpiece in the rigidly weak area;

[0075] S30, prepare a support structure based on the profiling support structure model;

[0076] S40, perform subtractive machining on the workpiece semi-finished product under the rigid compensation of the support structure to obtain the target workpiece.

[0077] The present invention enhances the rigidity of the rigidly weak area of the workpiece by quickly generating a functional support structure, thereby ensuring stability during the machining process and improving machining accuracy and surface quality.

[0078] Furthermore, the present invention conducts finite element analysis on the target workpiece, and defines the region with the maximum deformation of the target workpiece as the rigid weak region of the target workpiece. The profiling support structure models include a linear support model, a grid support model, a tree support model, a block support model, a column support model, a conical support model, and a trapezoidal support model. The support structures include a fully enclosed support structure, a semi-enclosed support structure, and an embedded support structure.

[0079] Furthermore, in the present invention, the support structure is prepared by 3D printing, especially by fused deposition modeling (FDM) printing. Among them, the printing material for 3D printing includes ethylene-vinyl acetate copolymer. The workpiece processing method of the present invention prepares the support structure and performs subtractive machining based on the same processing equipment, and the coordinate system in the subtractive machining process coincides with the coordinate system in the process of preparing the support structure.

[0080] As Figure 2 shown, the present invention also discloses a workpiece processing system 200, including:

[0081] A model construction module 21, configured to obtain the rigid weak region of the target workpiece, and construct a profiling support structure model based on the geometric features of the rigid weak region;

[0082] A first processing module 22, configured to process a workpiece semi-finished product, and the thickness of the workpiece semi-finished product in the rigid weak region is greater than the thickness of the target workpiece in the rigid weak region;

[0083] A support structure preparation module 23, configured to prepare a support structure based on the profiling support structure model;

[0084] A second processing module 24, configured to perform subtractive machining on the workpiece semi-finished product under the rigid compensation of the support structure to obtain the target workpiece.

[0085] The following further illustrates the present invention with specific embodiments.

[0086] Embodiment 1:

[0087] As Figure 3a shown, the target workpiece in this embodiment includes a blisk 20, the blisk 20 includes a disk 21 and a plurality of first blades 22 arranged at intervals along the circumferential direction of the disk 21 on the outer side wall of the disk, and the first blades 22 include a first outer surface 221 and a second outer surface 222 arranged opposite to each other. It can be understood that the rigid weak region of the blisk 20 includes the first blades 21.

[0088] It should be noted that the structural features of the target workpiece and the workpiece semi-finished product are similar (both can be referred to Figure 3aAs shown in the figure, the difference is that the semi-finished workpiece has a machining allowance extending in the first direction at the position corresponding to the first blade 22 (i.e., the rigid weak area of the blisk), that is, the thickness of the semi-finished workpiece in the rigid weak area is greater than the thickness of the target workpiece in the rigid weak area. Therefore, the structures of the target blisk and the blisk semi-finished product in this embodiment are both described by Figure 3a the structure shown.

[0089] A workpiece processing method in this embodiment specifically includes:

[0090] S21, obtain the rigid weak area of the target blisk, and construct a profiling support structure model based on the geometric features of the rigid weak area.

[0091] Step S21 in this embodiment specifically includes:

[0092] S211, construct a three-dimensional model of the target blisk, and define material properties based on the processing material of the target blisk:

[0093] Specifically:

[0094] Based on the modeling module of NX software, according to the design drawing requirements of the target workpiece (i.e., the blisk 20 as shown in Figure 3a the figure), construct a three-dimensional solid model of the target blisk, and define material properties based on the processing material of the target blisk. In this embodiment, the blisk made of aluminum alloy 6061 is taken as the specific implementation object;

[0095] In the preprocessing module of NX software, create a new FEM (finite element model) and simulation file, select the solver as Simcenter Nastran, and configure the solution type as "real eigenvalue" to complete the creation of the modal analysis engineering file.

[0096] Select the workpiece geometric model, and through the "assign material" function, load and bind the physical property parameters of Al6061 aluminum alloy from the NX material library. The physical property parameters include elastic modulus, Poisson's ratio, density, etc.

[0097] S212, perform mesh division on the three-dimensional model of the target blisk.

[0098] Specifically, use the CTETRA(10) type tetrahedral element to perform mesh division on the three-dimensional model of the target blisk, and set the mesh size to 1mm. This type of element has strong adaptability to complex surfaces and irregular geometric features, which can ensure the accuracy of modal analysis. In other optional embodiments, other types of elements can be selected for mesh division based on different target workpieces.

[0099] S213. Apply full - degree - of - freedom fixed constraints to the 3D model of the target blisk based on its clamping working conditions and material properties to simulate the rigid fixation state in actual machining.

[0100] S214. Obtain the natural frequencies and corresponding vibration mode data of each order of the target blisk, and generate a displacement nephogram. Specifically, it includes: calling the Solution module to perform real eigenvalue solution to obtain the natural frequencies and corresponding vibration mode data of the blisk, and generating a displacement nephogram through the post - processing interface.

[0101] S215. Extract the regions with the maximum deformation amount in each vibration mode based on the displacement nephogram, and define the region with the maximum deformation amount of the target workpiece as the rigid weak region of the blisk. Specifically: Based on the analysis of the displacement nephogram, extract the regions with the maximum deformation amount in each vibration mode and determine them as the rigid weak regions of the workpiece. For example, the region with an amplitude greater than the set amplitude threshold in the displacement nephogram is defined as the rigid weak region. Taking the blisk workpiece as an example, the tip region of its blade usually has a significantly higher amplitude than other regions and is generally recognized as a key rigid weak region.

[0102] S216. Construct a profiling support structure model based on the geometric features of the rigid weak region.

[0103] The profiling support structure model in this embodiment includes a linear support model, a grid - shaped support model, a tree - shaped support model, a block - shaped support model, a column - shaped support model, a conical support model, a trapezoidal support model, and custom supports that those skilled in the art can create based on the modeling function of NX software. In this embodiment, the trapezoidal support model is used to balance the support stiffness and material consumption.

[0104] As Figure 3b shown, for the geometric features of the cantilever of the blisk blade in this embodiment, a semi - wrapping profiling support structure model is selected for construction. In the profiling support structure model, a first support structure 231 and a second support structure 232 are designed for each first blade 22. The first support structure 231 corresponds to the first outer surface 221 of the first blade, and the second support structure 232 corresponds to the second outer surface 222 of the first blade. The first support structure 231 and the second support structure 232 form a semi - wrapping support for the blisk 20.

[0105] Furthermore, the set parameters in the profiling support structure model include the set contact surface of the profiling support structure model (corresponding to the surface in the support structure that needs to physically contact the rigid weak region of the workpiece semi - finished product) and the set thickness of the profiling support structure model.

[0106] As Figure 3cThe sectional view of the profiling support structure model shown, the semi-finished workpiece includes a workpiece main body part 201 and a surplus part 202 provided on the surface of the workpiece main body part 201 in its rigid weak area. The workpiece main body part 201 is the target workpiece, and the surplus part 202 is the reserved finishing allowance, that is, the part where the thickness of the semi-finished workpiece in the rigid weak area increases relative to the target workpiece in the rigid weak area. A gap is provided between the set contact surface of the profiling support structure model and the semi-finished workpiece, and the gap is used to prevent process interference during the support structure preparation process.

[0107] Specifically include:

[0108] Set the thickness of the semi-finished workpiece in the rigid weak area, and obtain the thickness L2 of the surplus part 202 based on the set thickness of the semi-finished workpiece in the rigid weak area and the thickness of the target workpiece in the rigid weak area;

[0109] The gap L3 between the set contact surface of the profiling support structure model and the semi-finished workpiece satisfies L3 = 0.5 * D, where D is the set layer height for each layer during the 3D printing process.

[0110] Furthermore, L3 = L2 - L1, where L1 is the distance between the set contact surface of the profiling support structure model and the target workpiece (i.e., the workpiece main body part 201).

[0111] Specifically, in this embodiment, the distance L1 between the first surface 2311 of the first support structure 231 and the first outer surface 221 of the workpiece main body part 201 (i.e., the blade theoretical profile) satisfies: L1 = L2 + (0.5 * D), where L2 is the thickness of the surplus part, that is, the reserved machining allowance, and D is the set layer height for each layer during the 3D printing process, thereby preventing interference during the printing process. Similarly, it can be known that in this embodiment, the distance L5 between the first surface 2321 of the second support structure 232 and the surface of the workpiece main body part 201 (i.e., the blade theoretical profile) also satisfies: L5 = L4 + (0.5 * D), and L4 is the thickness of the surplus part at the second outer surface 222 of the first blade 22.

[0112] Refer Figure 3d As shown, it should be noted that after the actual 3D printing is completed, there is no distance between the first surface 2311 of the first support structure 231 and the semi-finished workpiece.

[0113] In this embodiment, the set thickness of the support structure is dynamically adjusted according to the vibration amplitude of the rigid weak area, and the set thickness of the profiling support structure model is positively correlated with the vibration amplitude of the target workpiece in the rigid weak area. In this embodiment, the set thickness is adjusted based on the vibration amplitude of the first blade 22, and the greater the amplitude of the first blade 22, the greater the thickness increment of the support structure.

[0114] S22. Machine the semi-finished blisk, where the thickness of the semi-finished blisk in the weak rigidity region is greater than the thickness of the target blisk in the weak rigidity region. The structure of the semi-finished blisk can be referred to Figure 3a as shown.

[0115] Specifically, it includes:

[0116] Rough machine the disk of the blisk: Quickly remove the surplus material in the disk area of the blank.

[0117] Semi-finish machine the blades: Machine the semi-finished blisk, where the thickness of the semi-finished blisk in the weak rigidity region is greater than the thickness of the target blisk in the weak rigidity region. The thickness of the semi-finished blisk in the weak rigidity region strictly meets the thickness set during the process of constructing the profiling support structure model in step S21.

[0118] S23. Prepare the support structure based on the profiling support structure model.

[0119] It can be understood that the size of the support structure matches the size corresponding to the weak rigidity region.

[0120] Refer to Figure 3e as shown. Each first blade 22 includes two surfaces (the first outer surface 221 and the second outer surface 222 which are oppositely arranged). The first support structure 231 and the second support structure 231 proposed in this embodiment form a semi-wrapping support for the first blade 22.

[0121] Combined with Figures 3a to 3e as shown, step S23 specifically includes: Perform 3D printing on the first outer surface 221 of the first blade based on the profiling support structure model to obtain the first support structure 231, perform 3D printing on the second outer surface 222 of the first blade to obtain the second support structure 232. The first support structure 231 fits with the first outer surface 221 of the first blade, the second support structure 232 fits with the second outer surface 222 of the first blade, and the first support structure 231 covers the first outer surface 221 of the first blade, and the second support structure 232 covers the second outer surface 222 of the first blade.

[0122] Furthermore, in this embodiment, when preparing the support structure based on the profiling support structure model, it further includes:

[0123] S231. Set the printing device: In the NX additive manufacturing module, select the device model that matches the target FDM printer in the machine tool library, or reconfigure the printer device.

[0124] S232, Set the printing coordinate system: In this embodiment, the support structure is prepared and the subtractive machining is performed based on the same processing equipment. The coordinate system during the subtractive machining process coincides with the coordinate system during the preparation of the support structure. It can be understood that the machining coordinate system has been set in the subtractive process of machining the workpiece semi-finished product. Therefore, set the printing coordinate system to coincide with the machine tool machining coordinate system to ensure the positioning consistency between processes. Preferably, the printing additive process and the milling subtractive process are completed by the same five-axis machining center equipment.

[0125] S233, Set the printing nozzle parameters: Since the blades of the blisk are usually relatively high, the selected nozzle is relatively long, and the path needs to be completed through five-axis linkage. Therefore, it is necessary to set the nozzle shape and size. Usually, the nozzle size is set to be more than 1 mm larger than the actual size to prevent interference caused by the inconsistency between the ideal size and the actual size of the equipment.

[0126] S234, Print path programming: Since the structure of the blisk is relatively complex, selecting a multi-axis printing strategy can better complete the avoidance operation. At the same time, select the support part to be printed under this strategy as the printing target.

[0127] S235, Collision check: Use the machine tool simulation function to check whether interference occurs.

[0128] S236, Set the support printing parameters: Since the accuracy requirement for printing the support structure is relatively low and the efficiency requirement is relatively high, the selected printing parameters can be set according to the situation. In this embodiment, for a high printing speed, a 6 mm diameter nozzle with a larger flow rate is selected. The printing layer height during the printing process is set to 3 mm, the printing speed is set to 1000 mm / min, the filling method is selected as honeycomb or spiral with less idle travel, the filling density is selected as 25%, to ensure the support stability, and the printing material is selected as a high-viscosity EVA-based composite material (i.e., the printing material includes ethylene-vinyl acetate copolymer).

[0129] S237, G-code generation and verification: Convert the printing path into executable G-code for the target device through the NX post-processor, and use the virtual simulation module to verify that the code has no geometric interference, over-limit movement, and material accumulation defects.

[0130] S238, Execute the support printing process: After completing the blisk semi-finished product, replace the machine tool tool holder with an FDM printing device, calibrate the length of the printing equipment through the tool length sensor, clean the workpiece surface with an air gun, set the delivery of the consumables, execute the printing program, and drive the printing device to deposit the support material along the preset path.

[0131] It can be understood that after printing is completed, retract the printing device to the tool magazine and switch to the machining mode to facilitate the execution of the subtractive machining process.

[0132] S24, AsFigure 3e Under the rigid compensation of the shown support structure, subtractive machining is performed on the semi-finished workpiece. During the subtractive machining process, the thickness of the semi-finished workpiece in the rigid weak area is thinned, and the first support structure 231 and the second support structure 231 are removed to obtain the target workpiece.

[0133] Preferably, a cemented carbide tool is used in combination with a coolant to perform finish machining on the first blade 22, and the first support structure 231 and the second support structure 231 are removed synchronously during the finish machining process. Due to the hardness difference between the tool and the support material, the support structure can be ignored, and the first support structure 231 and the second support structure 231 on the first blade 22 can be peeled off. Finally, the remaining allowance of the disk 21 of the blisk and the remaining support structure are removed, without additional chemical or physical cleaning steps.

[0134] Example 2:

[0135] As Figure 4a shown, in this embodiment, the target workpiece includes an impeller. The impeller 30 includes a hub plate 31 and a plurality of second blades 32 arranged at intervals along the circumferential direction of the hub plate 31 on the outer side wall of the hub plate. The second blade 32 includes a relatively arranged third outer surface 321 and a fourth outer surface 322. The rigid weak area of the impeller 30 includes the second blade 32. It should be noted that for the impeller 30, the structural features of the target workpiece and the semi-finished workpiece are similar (both can be referred to Figure 4a shown), the difference is that the semi-finished workpiece is provided with machining allowance at the position corresponding to the second blade 32 (i.e., the rigid weak area of the impeller 30), that is, the thickness of the semi-finished workpiece in the rigid weak area is greater than the thickness of the target workpiece in the rigid weak area.

[0136] Specifically, the workpiece machining method in this embodiment includes:

[0137] S41, obtain the rigid weak area of the target workpiece, and construct a profiling support structure model based on the geometric features of the rigid weak area. Specifically, perform finite element analysis on the target workpiece, and define the area with the maximum deformation of the target workpiece as the rigid weak area of the target workpiece. Among them, the profiling support structure model includes a linear support model, a grid support model, a tree support model, a block support model, a column support model, a cone support model, and a trapezoid support model. The set thickness of the profiling support structure model is positively correlated with the vibration amplitude of the target workpiece in the rigid weak area.

[0138] S42, machine the semi-finished workpiece, and the thickness of the semi-finished workpiece in the rigid weak area is greater than the thickness of the target workpiece in the rigid weak area;

[0139] S43. Prepare a support structure based on the profiling support structure model. Specifically, in this embodiment, based on the profiling support structure model, 3D printing is performed in the rigid weak area of the semi-finished workpiece to obtain a support structure. The size of the support structure matches the size corresponding to the rigid weak area. The 3D printing includes fused deposition modeling printing, and the printing material for the 3D printing includes ethylene-vinyl acetate copolymer.

[0140] S44. Perform subtractive machining on the semi-finished workpiece under the rigid compensation of the support structure to obtain the target workpiece. Specifically, in this embodiment, subtractive machining is performed on the semi-finished workpiece to reduce the thickness of the semi-finished workpiece in the rigid weak area, and the support structure is synchronously removed to obtain the target workpiece.

[0141] It should be noted that for impeller-like workpieces (including ruled surface impellers, etc.), due to the high requirement for the surface finish of the second blade 32 of the impeller, side milling is usually used. In the case of side milling, the contact area between the cutting tool and the impeller workpiece increases, the cutting force increases, and the vibration also intensifies. Therefore, when designing the support structure, the support structure can be a fully enclosed support structure to provide a better support effect.

[0142] The workpiece processing method in this embodiment further includes:

[0143] Machine a semi-finished impeller. The thickness of the second blade of the semi-finished impeller is greater than the thickness of the second blade of the target impeller. Therefore, it can also be understood that the semi-finished impeller includes an impeller main body (whose size is equivalent to that of the target impeller) and a surplus part provided on the surface of the impeller main body;

[0144] As Figure 4b shown, based on the profiling support structure model, 3D printing is performed between the third outer surface 321 of the second blade 32, the outer side wall of the hub plate 31, and the fourth outer surface 322 of the adjacent second blade 32 to obtain a support structure 33. The support structure 33 is attached to the third outer surface 321 of the second blade 32, the outer side wall of the hub plate 31, and the fourth outer surface 322 of the adjacent second blade 32.

[0145] It can be understood that the steps such as the construction process of the profiling support structure model in this embodiment are similar to those in Embodiment 1, and will not be elaborated here.

[0146] Embodiment 3:

[0147] As Figure 5a 、 Figure 5b shown, in this embodiment, the target workpiece includes a housing-like workpiece 40. The housing-like workpiece includes a housing 42. An inner cavity 41 is formed on one side of the housing 42. The inner cavity 41 is disposed opposite to the housing 42 and has a shape and size that match each other, that is, the housing-like workpiece 40 is a hollow structure. The rigid weak area of the housing-like workpiece includes the housing 42.

[0148] Specifically, the workpiece processing method in this embodiment includes:

[0149] S51. Obtain the rigid weak area of the target housing workpiece, and construct a profiling support structure model based on the geometric features of the rigid weak area. Specifically, in this embodiment, finite element analysis is performed on the target workpiece, and the area with the maximum deformation of the target workpiece is defined as the rigid weak area of the target workpiece. Among them, the profiling support structure model includes a linear support model, a grid support model, a tree support model, a block support model, a column support model, a cone support model, and a trapezoid support model. The set thickness of the profiling support structure model is positively correlated with the vibration amplitude of the target workpiece in the rigid weak area.

[0150] S52. Machine a semi-finished housing workpiece, and the thickness of the semi-finished housing workpiece in the rigid weak area is greater than the thickness of the target workpiece in the rigid weak area;

[0151] S53. Prepare a support structure based on the profiling support structure model. Specifically, in this embodiment, based on the profiling support structure model, 3D printing is performed on the rigid weak area of the workpiece semi-finished product to obtain a support structure, and the size of the support structure matches the size corresponding to the rigid weak area. 3D printing includes fused deposition modeling printing, and the printing material for 3D printing includes ethylene-vinyl acetate copolymer.

[0152] S54. Under the rigid compensation of the support structure, perform subtractive machining on the semi-finished housing workpiece to obtain the target housing workpiece.

[0153] It should be noted that due to the thin-walled, complex-shaped, and hollow structural characteristics of the housing workpiece, its rigidity is poor. A support structure is arranged in the hollow part inside the shell (i.e., the part where the inner cavity is located) for filling, that is, an embedded support structure is provided to effectively improve the problem of insufficient rigidity of the shell parts and enhance the stability of part machining.

[0154] In this embodiment, the support structure can be directly printed on the first surface of the workpiece semi-finished product (i.e., the inner wall of the inner cavity), specifically including:

[0155] Machine a semi-finished housing workpiece, and the thickness of the shell of the semi-finished housing workpiece is greater than the thickness of the target housing workpiece. As Figure 6b shown, an inner cavity 41 is formed on one side of the semi-finished housing workpiece 401, and machining allowance is provided at a position opposite to the inner cavity 41;

[0156] Based on the profiling support structure model, 3D printing is performed on the inner wall of the inner cavity to obtain a support structure, and the first surface of the support structure fits the inner wall of the inner cavity. Under the rigid compensation of the support structure, perform subtractive machining on the workpiece semi-finished product to obtain the target workpiece, and then remove the support structure.

[0157] It should be noted that in addition to printing the support structure on the milled workpiece (i.e., the first surface of the semi-finished workpiece), the support structure can also be placed on the fixture to achieve the reuse of the support structure. For the convenience of clamping, a certain gap (such as 0.5 mm) needs to be left between the side of the support structure and the side wall of the inner cavity 41. Further, in this embodiment, the processing method of the support structure on the fixture requires clamping the target workpiece twice.

[0158] Combined with Figures 6a to 6d As shown, another workpiece processing method in this embodiment specifically includes:

[0159] Providing a blank 400 as Figure 6a shown, the blank 400 includes a first surface and a second surface arranged oppositely, clamping the blank, and performing rough machining, semi-finishing machining and finishing machining on the first surface of the blank 400 to obtain a semi-finished housing workpiece 401 as Figure 6b shown. As Figure 6b shown, an inner cavity 41 (shown by the dotted line in the figure) is formed on one side of the semi-finished housing workpiece 401, and a machining allowance extending in a direction away from the inner cavity 41 is formed on the other side;

[0160] As Figure 6c shown, performing 3D printing on the surface of the fixture 43 based on the profiling support structure model to obtain the support structure 44, wherein the first surface of the support structure 44 matches the size of the inner wall of the inner cavity. It can be understood that the support structure can just be embedded within the inner cavity 41. A gap is left between the side of the support structure and the side wall of the inner cavity 41, thereby realizing the reuse of the support structure 44, and the width of the gap is preferably 0.5 mm;

[0161] Combined with Figure 6c and Figure 6d shown, clamping the semi-finished housing workpiece 401 on the fixture 43, and making the first surface of the support structure 44 fit with the inner wall of the inner cavity 41, and performing subtractive machining, including rough machining, semi-finishing machining and finishing machining on the housing 42 (i.e., the outer surface opposite to the inner cavity) to obtain the target workpiece. After the subtractive machining is completed, removing the target workpiece from the support structure 44.

[0162] It can be understood that the construction process and other steps of the profiling support structure model in this embodiment are similar to those in Embodiment 1, and will not be elaborated here.

[0163] From the above technical solutions, it can be seen that the present invention has the following beneficial effects:

[0164] The workpiece processing method and workpiece processing system of the present invention prepare a support structure adaptable to workpieces of any complex shape, provide rigidity compensation for the weak rigidity areas of the workpieces, thereby ensuring stability during the processing, improving the processing accuracy and surface quality, without the need for additional customized fixtures, and without the need for additional chemical cleaning or physical cleaning steps;

[0165] The present invention solves the problems of geometric accuracy instability and surface quality deterioration caused by insufficient rigidity during the processing of complex weak-rigidity workpieces at a low cost, and effectively balances the processing quality, production efficiency and cost control;

[0166] The present invention can be intelligently printed through a numerical control system without increasing labor costs.

[0167] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced by the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0168] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A workpiece processing method, characterized in that, The workpiece processing method includes: Obtaining the rigid weak area of the target workpiece, and constructing a profiling support structure model based on the geometric features of the rigid weak area; Processing a workpiece semi-finished product, the thickness of the workpiece semi-finished product in the rigid weak area being greater than the thickness of the target workpiece in the rigid weak area; Preparing a support structure based on the profiling support structure model; Performing subtractive machining on the workpiece semi-finished product under the rigid compensation of the support structure to obtain the target workpiece.

2. The workpiece processing method according to claim 1, characterized in that, Obtaining the rigid weak area of the target workpiece includes: Performing finite element analysis on the target workpiece, and defining the area with the maximum deformation amount of the target workpiece as the rigid weak area of the target workpiece.

3. The workpiece processing method according to claim 1, characterized in that, The profiling support structure model includes a linear support model, a grid support model, a tree support model, a block support model, a column support model, a cone support model, and a trapezoid support model; and / or, The support structure includes a fully wrapped support structure, a semi-wrapped support structure, and an embedded support structure.

4. The workpiece processing method according to claim 1, characterized in that, The set thickness of the profiling support structure model is positively correlated with the vibration amplitude of the target workpiece in the rigid weak area.

5. The workpiece processing method according to claim 1, characterized in that, The workpiece processing method includes: preparing the support structure by 3D printing.

6. The workpiece processing method according to claim 5, characterized in that The printing material for the 3D printing includes ethylene-vinyl acetate copolymer; and / or, The 3D printing includes fused deposition modeling printing.

7. The workpiece processing method according to claim 5, wherein, Based on the profiling support structure model, performing 3D printing on the rigid weak area of the workpiece semi-finished product to obtain a support structure, the size of the support structure matching the size of the rigid weak area; and / or, Based on the profiling support structure model, performing 3D printing on the surface of the tooling to obtain a support structure, the size of the support structure matching the size of the rigid weak area.

8. The workpiece processing method according to claim 1, characterized in that, Performing subtractive machining on the workpiece semi-finished product to reduce the thickness of the workpiece semi-finished product in the rigid weak area, and synchronously removing the support structure to obtain the target workpiece.

9. The workpiece processing method according to claim 1, wherein The workpiece processing method further includes: Preparing the support structure and performing subtractive machining based on the same processing equipment, and the coordinate system in the subtractive machining process coincides with the coordinate system in the process of preparing the support structure.

10. The workpiece processing method according to claim 1, characterized in that, The target workpiece includes a blisk, the blisk includes a disk and a plurality of first blades arranged at intervals along the circumferential direction of the disk on the outer side wall of the disk, the first blades include a first outer surface and a second outer surface arranged oppositely, and the rigid weak area of the blisk includes the first blades; The workpiece processing method further includes: Processing a blisk semi-finished product, the thickness of the first blades of the blisk semi-finished product being greater than the thickness of the first blades of the target blisk; Preparing a first support structure on the first outer surface of the first blades of the blisk semi-finished product, and preparing a second support structure on the second outer surface of the first blades of the blisk semi-finished product, the first support structure fitting the first outer surface of the first blades, and the second support structure fitting the second outer surface of the first blades.

11. The workpiece processing method according to claim 1, characterized in that, The target workpiece includes an impeller, the impeller includes a hub plate and a plurality of second blades arranged at intervals along the circumferential direction of the hub plate on the outer side wall of the hub plate, the second blades include a third outer surface and a fourth outer surface arranged oppositely, and the rigid weak area of the impeller includes the second blades; The workpiece processing method further includes: Processing a semi-finished impeller, wherein the thickness of the second blade of the semi-finished impeller is greater than the thickness of the second blade of the target impeller; Preparing a support structure between the third outer surface of the second blade of the semi-finished impeller, the outer side wall of the hub plate, and the fourth outer surface of the adjacent second blade, and the support structure is attached to the third outer surface of the second blade, the outer side wall of the hub plate, and the fourth outer surface of the adjacent second blade.

12. The workpiece processing method according to claim 1, characterized in that, The target workpiece includes a housing workpiece, the housing workpiece includes a housing, an inner cavity is formed on one side of the housing, and the rigid weak area of the housing workpiece includes the housing; The workpiece processing method further includes: Processing a semi-finished housing workpiece, wherein the thickness of the housing of the semi-finished housing workpiece is greater than the thickness of the target housing workpiece; Preparing a support structure on the inner wall of the inner cavity or the surface of the tooling, and the support structure is matched with the size of the inner wall of the inner cavity.

13. A workpiece processing system, characterized in that, Including: A model construction module, configured to obtain the rigid weak area of the target workpiece and construct a profiling support structure model based on the geometric features of the rigid weak area; A first processing module, configured to process a semi-finished workpiece, and the thickness of the semi-finished workpiece in the rigid weak area is greater than the thickness of the target workpiece in the rigid weak area; A support structure preparation module, configured to prepare a support structure based on the profiling support structure model; A second processing module, configured to perform subtractive processing on the semi-finished workpiece under the rigid compensation of the support structure to obtain the target workpiece.

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