Multi-step combined forming method for porous conical cylindrical curved surface component

Abstract

The application belongs to the technical field of high-end manufacturing, and provides a multi-process composite forming method and device for a porous conical cylindrical curved member, which comprises the following steps: providing a heated metal flat plate blank; performing laser punching on the metal flat plate blank to form a porous plate with dot array holes; performing deep drawing processing on the porous plate when the porous plate is in a first preset temperature range to form a porous straight cylinder member; performing blanking on the bottom of the porous straight cylinder member; controlling the temperature of the blanked porous straight cylinder member to be in a second preset temperature range, and performing multi-pass bulging-spinning composite forming at the temperature until the member reaches a target curved surface profile; and performing profile inspection on the formed member. The process route breaks the bottleneck that the traditional technology cannot simultaneously ensure precision and preform holes, avoids the emergence of a welding mode, and provides reliable technical support for the large-scale and consistent production of high-precision porous curved surface members.

Description

Technical Field

[0001] This application belongs to the field of high-end manufacturing technology, and specifically relates to a multi-process composite forming method for porous conical curved surface components. Background Technology

[0002] Porous conical curved surface components, with their combined advantages of high strength and excellent heat dissipation, have become key heat dissipation and load-bearing components in aerospace, high-end equipment, and other fields with stringent thermal management requirements. Through their unique porous structure design, these components achieve efficient heat conduction and dissipation while ensuring structural load-bearing capacity, directly impacting the operational stability and service life of the final equipment. With the continuous upgrading of the performance of aircraft and other equipment, increasingly stringent requirements have been placed on the manufacturing precision and production efficiency of porous conical curved surface components, making traditional manufacturing technologies inadequate for this development trend.

[0003] However, porous conical cylindrical curved surface components are not simply conical inclined surface structures; their complex curved surface features pose significant challenges to high-precision and automated manufacturing. Currently, both of the industry's mainstream forming technologies suffer from core defects that are difficult to overcome: Firstly, the use of hydraulic bulging technology faces a dilemma between "pre-drilled holes and forming accuracy." If holes are pre-drilled before bulging, the process of sealing and treating these holes after bulging will inevitably damage the high-precision curved surface of the component, seriously affecting the surface accuracy and consistency of the final product. If drilling is performed on the complex curved surface after bulging to avoid this problem, it faces problems such as extremely difficult drilling positioning and complex processing technology. Therefore, most of the time, the whole component is often bulged in sections and then drilled, and finally welded into a whole. This inevitably introduces weld seams, leading to a reduction in component performance.

[0004] Secondly, the use of internal and external rigid mold constraint segmented bulging technology results in high mold costs and difficulties in demolding. To avoid the hole handling problems of hydraulic bulging, the industry has tried using internal and external rigid mold constraint segmented bulging technology, but this has introduced multiple new obstacles. The accuracy of this technology is highly dependent on the external mold constraint that is completely in contact with the product's outer surface, leading to complex mold structure design, high processing difficulty, and a sharp increase in mold manufacturing costs. During the forming process, the conical part is prone to "biting" or sticking with the surfaces of the internal and external molds, requiring a lot of manual intervention during demolding. This not only seriously restricts production efficiency but may also affect product consistency due to differences in manual operation, further increasing the difficulty of quality control.

[0005] In summary, neither of the existing hydraulic bulging nor internal and external rigid mold constrained segmented bulging technologies can simultaneously achieve the forming accuracy and cost reduction and efficiency improvement goals of multi-hole conical curved surface components, becoming a technical bottleneck restricting their large-scale application in high-end fields such as aerospace. Summary of the Invention

[0006] To address the above problems, this application provides a multi-stage composite forming method for porous conical curved surface components, comprising the following steps: Provide heated metal plate blanks; Laser drilling is performed on metal flat blanks to form a porous plate with a lattice of holes. When the perforated plate is within the first preset temperature range, it is deep drawn to form a perforated straight cylindrical component. The bottom of the porous straight cylindrical component is punched; The temperature of the punched porous straight cylindrical component is controlled within a second preset temperature range, and multiple bulging-spinning composite forming is performed at this temperature until the component reaches the target curved surface profile. In each pass, the punch drives the segmented die to bulge to an intermediate target profile. Then, while the segmented die is kept expanded as an internal support, a spinning wheel is used to spin-shape the workpiece to make it fit the mold. Perform contour inspection on the formed components.

[0007] Furthermore, the metal plate blank is a circular slab with a solid, un-drilled area reserved in the middle. The diameter of the solid area is adapted to the inner diameter of the porous straight cylindrical component formed by deep drawing.

[0008] Furthermore, the diameter of the solid region satisfies: , where d s Let d be the inner diameter of the porous straight cylindrical component. t Let k be the target diameter at one end of the porous conical cylinder component. t The safety factor ranges from 0.5 to 0.8.

[0009] Furthermore, the initial hole diameter and hole spacing on the metal plate blank are determined based on the target hole parameters of the porous conical cylinder component and calculated using a predetermined verification method to compensate for the deformation effects caused by subsequent deep drawing and bulging processes.

[0010] Furthermore, the verification methods include: The proportionality coefficients of the influence of deformation on hole diameter and hole spacing are obtained through process simulation. Calculate the initial hole diameter and hole spacing based on the influence ratio coefficient and the target hole parameters.

[0011] Furthermore, the number of lobes in the bulging mold shall not be less than 8.

[0012] Furthermore, after the segmented mold has fully expanded, the gap between adjacent modules satisfies: t b ≤0.3 l b , where t b For the gap, l b This is the arc length of the working surface of a single module.

[0013] Furthermore, the segmented die is provided with a limiting structure to constrain the axial movement of the sheet metal during the bulging process.

[0014] Furthermore, the limiting structure is a limiting plate, one end of which is provided with a hypotenuse, and the inclination angle α of the hypotenuse ranges from 10° to 20°.

[0015] Furthermore, the height of the segmented die is greater than the height of the porous cylindrical component formed by deep drawing.

[0016] Furthermore, the segmented mold achieves bulging and repositioning by sliding a slider at its bottom within a groove in the mold base. The slider's stroke satisfies the following conditions: , where L h d represents the total stroke of the slider. t Let d be the target diameter at one end of the component. s The inner diameter of the porous straight cylindrical component.

[0017] Furthermore, the contact height of the wheel surface is 3 to 6 times the original thickness of the metal plate blank.

[0018] Furthermore, the total number of passes N in the bulging-spinning composite forming process is determined by the following formula: Where ceil is the floor function, and d t Let d be the target diameter at one end of the component. s denoted as the inner diameter of the porous straight cylindrical component, and r is the diameter bulging ratio for a single pass, ranging from 5% to 10%.

[0019] Furthermore, the additional length of the segmented die relative to its bulging is 1.5 to 3 times the thickness of the original metal plate blank.

[0020] Furthermore, the angle of the punch, the angle of the segmented die, and the tilt angle α are the same.

[0021] Furthermore, the proportionality coefficients for obtaining the influence of deformation on the aperture and aperture spacing through process simulation include: The aperture on the flat blank is equal to the aperture on the porous conical part; The vertical spacing between the holes on the flat blank is equal to the vertical spacing between the holes on the multi-hole tapered cylinder part. The left-right spacing of the holes on the flat blank is equal to the left-right spacing of the holes on the multi-hole conical cylinder part; The deep drawing and bulging simulation is performed based on the initial porous flat blank drawing; The vertical and horizontal spacing of the porous holes in the final simulation results are measured to obtain the proportional coefficient of the influence of deformation on the hole diameter and its spacing.

[0022] Furthermore, the segmented mold slides within a groove on the mold base via a slider at its bottom to achieve bulging and repositioning, including: A guide rod is provided in the groove, and an elastic element is sleeved on the guide rod. The split mold abuts against the guide rod.

[0023] Compared with the prior art, this application has the following advantages: Compared to the dilemma faced by traditional hydraulic bulging processes—where pre-drilling holes damages the curved surface, while post-drilling holes presents positioning difficulties and stress release impacts accuracy—this solution adopts an innovative approach: "precision drilling on a flat plate followed by bulging and then integral spinning." This process completes all high-precision laser drilling at the flat plate blank stage, ensuring hole position accuracy from the outset. Subsequently, the perforated plate is integrally composite-formed, achieving a high-precision curved surface in one step. This completely avoids the weld seam and performance degradation problems introduced by traditional processes involving segmented forming and welding assembly, providing a reliable solution for the large-scale, consistent manufacturing of high-precision multi-hole curved surface components. Compared to the segmented bulging technology constrained by internal and external rigid molds, this solution abandons the complex external rigid mold that is indispensable in traditional segmented bulging and completely conforms to the component's outer contour. Instead, after bulging, the segmented mold itself serves as an internal support, and a spinning wheel is used for outer surface spinning and shaping. This combination of "internal expansion + external rotation" greatly simplifies the mold structure (requiring only a split mold and a rotating wheel), significantly reducing the mold's design complexity, processing difficulty, and manufacturing cost, and also drastically shortening the mold preparation cycle.

[0024] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 A front view of a porous conical curved surface component according to an embodiment of this application is shown; Figure 2 A partial enlarged view of the porous conical curved surface component according to an embodiment of this application is shown; Figure 3 A schematic flowchart of a multi-step composite forming method for a porous conical curved surface component according to an embodiment of this application is shown. Figure 4 This is a diagram of the initial porous metal plate structure. Figure 5 This is a magnified view of a portion of the initial porous metal plate. Figure 6 This is a structural diagram of a straight cylindrical porous component; Figure 7 This is a structural diagram of the bulging-spinning straightening die; Figure 8 This is a diagram of the bottom structure of the split mold; Figure 9 This is a structural diagram of the lower mold base for bulging. Figure 10 for Figure 9 Half-section view of section AA of the bulging lower mold base; Figure 11 This is a structural diagram of the bulging die punch; Figure 12 This is a diagram of the rotating wheel structure.

[0027] in: 1. Punch; 2. Bolt; 3. Limiting plate; 4. Split die; 5. Bulging lower die base; 6. Rotating wheel; 7. Robotic arm; 8. Support rod; 9. Positioning hole; 10. First through hole; 11. Slider; 12. Second through hole; 13. Slide groove; 14. Spring mounting hole; 15. Spring; 16. Guide rod. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] The high-temperature alloy porous conical curved surface component to be formed in this embodiment is as follows: Figure 1 and Figure 2 As shown, the diameter d of its smaller end face t It is 251mm in diameter and has a bottom diameter d. f It is 346mm long and has an arc length of L. z It is 89.6mm, and the height is h. z The plate is 70mm thick and 1mm wide. The target hole diameter r on the component is... z The hole spacing is 0.4mm, and the vertical spacing L is... z1 It is 1.5mm, and the left and right spacing is L. z2 It is 9.8mm.

[0030] First, determine the diameter d of the original circular flat plate blank according to formula (1).b The formula is as follows:

[0031] Calculated d b =251mm + 2 × 89.6mm + 8mm (with a margin of 8mm) ≈ 440mm, where L t This is a margin. A diameter d is reserved at the center of the billet. c The solid area is not drilled, and the diameter d c The inner diameter d of the straight cylindrical part formed by subsequent deep drawing s Same. Determined according to formula (2), mainly to ensure that each part of the component undergoes a certain amount of plastic deformation during the bulging process, and to prevent cracking, specifically:

[0032] k t For safety factors, the value ranges from 0.5 to 0.8; in this embodiment, it is set to 0.65. Therefore, d... s The value range is 163.15mm~251mm, and in this embodiment, d is taken as... s =200mm, therefore d c =200mm.

[0033] like Figure 3 As shown, this embodiment provides a multi-process composite forming method for porous conical curved surface components, including: Step S101: Provide a heated metal plate blank.

[0034] Step S102: Laser drilling is performed on the metal flat plate blank to form a porous plate with a lattice of holes, such as... Figure 4 As shown. Specifically, the key to this application is that it does not simply form the perforated sheet material directly, but rather, through process simulation and verification calculations, it accurately predicts how the shape and spacing of the holes will change during subsequent plastic deformations such as deep drawing and bulging (e.g., hole diameter enlargement, hole spacing elongation). Then, it reverse-engineers (compensates) the size and spacing of the holes on the initial flat blank.

[0035] In the precision assurance stage (laser drilling), the highest precision requirements for the holes are first met in an independent and optimized environment (laser processing). In subsequent processes, the focus is on solving the problem of forming complex curved surfaces. At this point, the holes have become an inherent property of the blank, and the forming process only needs to focus on how to efficiently and with high quality deform the blank with holes into the target curved surface, without having to be distracted by the machining of the holes.

[0036] Lasers excel at drilling precision holes on flat surfaces, while spun forming excels at shaping complex curved surfaces. The process route of this application connects them in series and uses pre-compensation (i.e., reverse design of the size and spacing of holes on the initial flat blank) as a link to enable them to work together, ultimately achieving efficient parallel assurance of "hole accuracy" and "surface accuracy," breaking the bottleneck of mutual constraints between the two in traditional processes.

[0037] Specifically, such as Figure 5 As shown, to compensate for deep drawing and bulging deformation, the initial hole parameters on the flat blank need to be designed. The verification method is as follows (see [reference needed]). Figure 2 , Figure 5 There is a verification method for the hole diameter and the spacing between holes in the initial flat blank. First, assume that the hole diameter r on the flat blank is... b The aperture r on the porous tapered part z The vertical spacing L of the holes on the flat blank is equal. b1 The vertical spacing L of the holes on the multi-hole conical cylinder part z1 Equal, the left and right spacing L of the holes on the flat blank b2 The left and right spacing L of the holes on the multi-hole conical cylinder part z2 Equal; then, based on the assumptions, an initial porous flat blank is drawn to simulate deep drawing and bulging, and the pore diameter r of the final simulation result is calculated. s The vertical spacing L of the holes s1 and left and right spacing L s2 Measurements were taken to obtain the proportional coefficient of the influence of deformation on the aperture and its spacing, and the formula (3) was used for calculation; finally, based on the calculated proportional coefficient of the dimensional influence caused by deformation and the aperture r of the multi-hole conical part, the results were obtained. z and the vertical spacing L of its holes z1 and left and right spacing L z2 Specifically, let's first assume the blank hole diameter r. b =r z =0.4mm, hole spacing L b1 =L z1 =1.5mm, L b2 =L z2 =9.8mm, process simulation was performed. The simulated pore size (the simulated pore size) r was obtained after deformation. s =0.46mm, Spacing (vertical spacing between holes) L s1 =1.64mm, the left and right spacing of the hole L s2 =10.93mm. The influence ratio coefficient k is calculated according to formula (3). r =0.4 / 0.46≈0.87, k1=1.5 / 1.64≈0.91, k2=9.8 / 10.93≈0.90, formula (3) is:

[0038] in, This is the proportionality coefficient for the effect of deformation on aperture. This is a proportionality coefficient representing the effect of deformation on the vertical spacing of the holes. This is the proportionality coefficient for the influence of deformation on the left and right spacing of the hole.

[0039] Then, by reverse calculation using formula (4), the initial hole diameter r to be machined on the blank can be obtained. b =0.87×0.4mm≈0.35mm, initial hole vertical spacing L b1 =0.91×1.5mm≈1.37mm, left and right spacing L b2 =0.90×9.8mm≈8.82mm. Formula (4) is:

[0040] Subsequently, the billet heated to 1000°C is positioned at the laser drilling station and processed into a regular multi-hole matrix according to the above design parameters.

[0041] Step S103: When the perforated plate is within the first preset temperature range, it is deep-drawn to form a perforated cylindrical component. Specifically, the temperature of the laser-processed perforated plate is measured. If the temperature (e.g., 880℃) is higher than the minimum forming temperature (800℃), it is transferred to a deep-drawing die for deep drawing to form an inner diameter d. s For a height of 200mm, if the forming temperature is below the minimum, reheat until the height h is within the first preset temperature range. s The perforated straight cylindrical component with a diameter of 120mm is calculated according to formula (5) (see reference). Figure 4 and Figure 6 The formula is:

[0042] Then, the cylindrical component is clamped and its bottom is punched. That is, step S104 is performed to punch the bottom of the perforated cylindrical component.

[0043] Step S105: Control the temperature of the punched porous straight cylindrical component within a second preset temperature range, and perform multi-pass bulging-spinning composite forming at this temperature until the component reaches the target curved surface contour. If the temperature does not reach the second preset temperature range, it needs to be reheated until it meets the second preset temperature range. In each pass, the punch drives the segmented die to bulge to an intermediate target contour. Then, while the segmented die remains expanded as an internal support, the spinning wheel 6 is used to spin-shape the workpiece to make it fit the mold. Specifically, as shown... Figures 7 to 12As shown, the bulging-spinning composite die mainly includes a punch 1, a segmented die 4, a limiting plate 3, a lower die base, and a spinning wheel 6. The number of segments in the segmented die 4 is determined by the number of segments. Each segmented die 4 has a limiting plate 3, which restricts the upward movement of the sheet metal during the bulging process. The limiting plate 3 has four positioning holes 9, and a first through hole 10 in the center for engagement with bolts 2. The size of the first through hole 10 is the same as the size of the second through hole 12 on the segmented die 4. Figure 8 As shown. The other end of the limiting plate 3 is a bevel. The bevel angle γ of the segmented mold 4 is the same as the bevel angle α, both ranging from 10 to 20°. This is designed to prevent the punch from self-locking when sliding on the bevel. Furthermore, to ensure that the punch 1 can slide smoothly on the segmented mold 4, the angle β of the punch 1 is consistent with the bevel angle γ of the segmented mold 4. The thickness h of the limiting plate 3 is... x The value ranges from 5 to 15 mm, and the additional length t relative to the bulging segmented mold is... x It is 1.5 to 3 times the thickness of the original metal plate blank.

[0044] The height of the segmented mold 4 is h. f It must be greater than the height h of the straight cylindrical part. s The height is 3-6mm, and its other side is a bevel. The angle of punch 1 is the same as the bevel angle α of the limiting plate 3. The segmented mold 4 has a second through hole 12, which is fitted with a bolt. There is a slider 11 at the bottom, and the height of slider 11 is h. b The value range is 5~15mm, and the radius R of the arc at one end of slider 11 is... h Same as the bolt radius. Furthermore, the height h of the segmented mold... f Height h of straight cylindrical parts s The height is 4mm, which is 124mm. The angle α of the inclined side of the limiting plate 3 is 15°, and its protruding length t x The stroke is 3mm. The slider 11 at the bottom of the split mold has a stroke L. h Take 30mm, satisfying L h The requirement of >(251-200) / 2=25.5mm is met, which means that formula (6) is satisfied: (6). Working stroke s of spring 15 w The length is 20mm, and the free length L0 is 40mm. The contact surface height h of the rotating wheel 6 is... r It is 3-6 times the original slab thickness. Specifically, the contact surface height h of the spinning wheel 6... r Take 4 times the plate thickness, i.e., 4mm. Measure the temperature of the punched cylindrical component. If the temperature is below 800℃ (e.g., 720℃), return it to the furnace for 10 minutes. The total number of forming passes N is calculated according to formula (7). The single-pass bulging rate r is taken as 8%, and the range of r value is 5%-10%. Therefore, N=ceil(ln(251 / 200) / ln(1+0.08)=3 passes. The formula is:

[0045] It should be noted that, in order to ensure the surface accuracy of the segmented bulging component and prevent obvious ridges or unevenness from appearing on the component surface due to excessive gaps in the segmenting mold, the final bulging gap t of the segmenting mold needs to be adjusted. b Perform the verification. The verification is based on formula (8): t b ≤0.3l b (8) Among them, l b This is the arc length of the working surface of a single segmented mold.

[0046] Given that the number of segments is 16, the final target diameter of the component after bulging is 251 mm (i.e., the diameter d at the small end). t Therefore, the circumference of the inner cavity formed by the segmented mold is C = π × d. t ≈3.14×251≈788.14mm.

[0047] The sum of the arc length and gap of the working surface of a single segmented mold, t b +l b =C / 16≈788.14 / 16≈49.26mm According to formula (8), the maximum allowable gap t b (max)≈11.37mm.

[0048] Design gap t b =11.28mm, which meets the requirement of 11.28mm≤11.37mm. Therefore, the design is reasonable and can effectively ensure the quality of the formed curved surface.

[0049] To ensure that the slider 11 has sufficient rigidity and to prevent deformation during the bulging process, its edge width t h and edge length L b The verification must meet the requirements of formula (9):

[0050] Given that the radius R of the arc at one end of slider 11 h =6mm. Therefore, the design value t is taken as 6mm. h =6mm, L b =8mm, all of which meet the requirement of ≥6mm, ensuring the rigidity of slider 11.

[0051] refer to Figure 9 and Figure 10 The bulging lower mold base 5 has a clearance fit between the slide groove 13 and the slide block 11, and the width of the slide groove 13 is W. c The width is the same as that of slider 11. To reduce the friction between slider 11 and groove 13, the depth of groove 13 is t. c It must be greater than the height h of slider 11b The length L of the slide groove 13 c Determined according to the following formula (10):

[0052] The length L of the groove 13 on the bulging lower mold base 5 is... c It needs to accommodate the movement of slider 11 and is determined according to formula (10); Given the value L b =8mm,R h =6mm,L h Substituting 30mm into the formula, we get: L c =2×(8+6+30)=2×44=88mm This length ensures that slider 11 slides smoothly within its travel range.

[0053] To ensure the rigidity of the lower die holder 5, the height h of the lower die holder 5 is... m The depth should be greater than twice the 13t of the groove. c .

[0054] Spring 15 is installed in the hole of slide groove 13 in lower mold base 5. Guide rod 16 is sleeved on spring 15, with one end of guide rod 16 being arc-shaped to facilitate the installation and guidance of spring 15. One side of segmented mold 4 abuts against guide rod 16. This allows segmented mold 4 to slide within slide groove 13 of mold base via its bottom slider to achieve expansion and repositioning. The diameter d of spring mounting hole 14 is... h It should satisfy formula (11).

[0055]

[0056] In the formula Indicates the width W of groove 13 c and 13-meter deep groove c The minimum of the two. Specifically, given W... c =18mm, t c =10mm, therefore min(W) c , t c =10mm. For ease of processing and installation, the design takes d as 10mm. h =8mm, to meet the requirement of less than 10mm.

[0057] To facilitate the installation of spring 15, the diameter of spring 15 is... It should be slightly smaller than the diameter of the mounting hole. It satisfies the following formula:

[0058] In the formula The gap is defined as d, with a value ranging from 1 to 2 mm. t =d h l g =8 1 = 7mm.

[0059] Spring 15 working stroke It must be less than the total stroke of slider 11, which is the distance L between sliders 11. h To prevent spring 15 from bending in its free state, the free length L0 of spring 15 should be greater than or equal to 3 / 2 of the working stroke of spring 15. .

[0060] Furthermore, the spring mounting hole 14 has a depth of L. h And guide rod 16 length L d The formula should be satisfied:

[0061] Given that the free length of spring 15 is L0 = 40 mm, and the working stroke is s w =20mm, then: L h =40 20 = 20mm Guide rod 16, length L d It needs to be between 1 / 3×40≈13.3mm and 2 / 3×40≈26.7mm, and less than or equal to L. h =20mm. Therefore, take L. d =18mm is reasonable.

[0062] Guide rod 16 diameter d d Calculate (gap l) according to formula (14) g Still take 1mm): =7 1 = 6mm (14) like Figure 11 As shown, the angle β of punch 1 (bulging die punch) and the angle α of the inclined side of the limiting plate 3 are the same. The height h of the bulging die punch 1 is... c It must be sufficient to ensure that the segmented model can be fully driven, and must satisfy formula (15): (15) Given the thickness h of the limiting plate 3 x =10mm, segmented mold height h f =124mm, therefore h x +h f =134mm. The punch height h in the original document... c=140mm meets the requirement of being greater than 134mm, and the design is reasonable.

[0063] Repeat the bulging-spinning composite forming steps until the component reaches the target curved surface profile. Specifically, place the workpiece on the composite station. In the multi-pass bulging process, the intermediate target diameter d of each pass... i It is calculated based on the diameter of the previous pass using a fixed bulging ratio. The calculation formula is: (16) In the formula The target diameter of the workpiece at the intermediate point of the (i-1)th pass.

[0064] In this example, the single-stage diameter bulging ratio r = 8%, and the initial diameter d s =200mm.

[0065] First pass: The punch presses down, pushing the split die to expand radially, and according to formula (16), the inner diameter of the upper end of the workpiece is expanded from 200mm to 216mm. The punch stops pressing down, and the split die continues to expand as an internal support. At this time, the CNC rotary wheel 6 spins and shapes the workpiece along this intermediate contour trajectory, so that it completely fits the die, and the rotary wheel 6 withdraws.

[0066] Second pass: Repeat the above process, expand the inner diameter from 216mm to 233.28mm according to formula (16) and perform spinning correction, and remove the blade from the spinning wheel 6.

[0067] Third pass (final pass): The inner diameter is bulged from 233.28 mm to the target diameter of 251 mm according to formula (16), and then fine-tuned.

[0068] As the rotary wheel 6 retracts its blade and the punch returns to its original position, the split mold contracts under the elastic force of the spring 15, smoothly separating from the formed component and achieving stable demolding.

[0069] Step S107: Perform contour inspection on the formed component. Specifically, perform shape contour dimension inspection on the finally formed porous conical curved surface component, mark it if it passes inspection, and transfer it to the storage area.

[0070] Furthermore, this embodiment includes multiple temperature monitoring and reheating steps to ensure that each process is carried out within the optimal plastic forming temperature range of the material, effectively preventing cracking or incomplete forming due to insufficient temperature. Simultaneously, it provides clear calculation formulas and value ranges for key parameters such as the diameter of the solid area in the center of the blank, the number and gap of the segmented molds, the stroke of slider 11, the size of the spinning wheel 6, and the number of forming passes, providing a quantitative basis for the stable implementation of the process and ensuring the quality stability of mass production. Through a scientific hole design verification method, the influence of plastic deformation on the hole diameter and hole spacing is pre-compensated, producing qualified initial blanks in one go, reducing trial-and-error costs and material waste. The entire process has a high degree of integration, is easy to automate and streamline production, and meets the modern manufacturing industry's pursuit of low cost and high efficiency.

[0071] It should be noted that this embodiment also includes a support rod 8 and a robotic arm 7. One end of the robotic arm 7 is slidably mounted on the support rod 8 and can move up and down along the height of the support rod 8. The other end of the robotic arm 7 is equipped with a rotating wheel 6. Additionally, Figure 12 h a The height of the spool is used to ensure the structural rigidity of the spool. Its value is determined based on hr and must meet the following conditions: Rotary wheel 6 height h a The contact surface height h of the rotating wheel 6 is greater than twice that of the rotating wheel 6. r To ensure the spinning wheel body has sufficient strength and rigidity to withstand the enormous pressure generated during spinning without deformation, thus guaranteeing forming accuracy. The contact surface height h of the spinning wheel 6 in this application is... r It is four times the thickness of the original slab, providing sufficient contact area during spinning to uniformly transfer force and effectively suppress wrinkling of the slab.

[0072] h r and h a These are the key design parameters of the 6-wheel mechanism, ensuring that it can work effectively and has the necessary structural strength.

[0073] In summary, this application also has the following advantages: Since there is no external rigid die to cover and constrain the part, after spinning and shaping, only the return stroke of punch 1 needs to be driven. The split die 4 can automatically shrink under the action of the reset mechanism (such as spring 15) and separate from the inner wall of the component, achieving non-destructive, fast, and stable demolding. This completely solves the problems of difficult demolding, excessive manual intervention, and easy damage to the surface of the component caused by "die biting" or adhesion in traditional internal and external rigid die bulging. It effectively improves the level of production automation and the first-pass yield of products, and ensures the consistency of the surface quality and dimensional accuracy of the component.

[0074] This solution provides a complete set of parameter design and control methods, forming a closed-loop technology system from billet design to final forming. It includes: Blank design: The initial hole diameter and hole spacing are back-calculated by verification methods (such as formulas (1)-(5)) to compensate for subsequent plastic deformation and ensure the accuracy of the final hole parameters.

[0075] Process planning: Formula (8) controls the gap of the split mold 4, formula (6) determines the slider stroke, and formula (7) calculates the total number of forming passes, providing quantitative guidance for the stable implementation of the process.

[0076] Process control: The temperature windows for key processes such as deep drawing (first preset temperature) and bulging-spinning (second preset temperature) were defined, as well as the range of key parameters such as the contact height of the spinning wheel and the angle of the limiting plate.

[0077] This system transforms the entire forming process from "trial and error based on experience" to "scientific controllability," improving the success rate and repeatability of the process and providing universal guidance for the process development of components of different specifications.

[0078] By accurately calculating the blank dimensions (as in formula (1)) and optimizing the process path, the material processing allowance and waste generation are reduced. At the same time, the introduction of spinning process can refine the material grains while forming, improve the hardness and smoothness of the component surface, thereby further improving the comprehensive mechanical properties of the component while ensuring dimensional accuracy.

[0079] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A multi-process composite forming method for a porous conical curved surface component, characterized in that, Includes the following steps: Provide heated metal plate blanks; The metal plate blank is laser-drilled to form a porous plate with a lattice of holes; When the perforated plate is within a first preset temperature range, it is subjected to deep drawing to form a perforated cylindrical component. The bottom of the porous straight cylindrical component is punched; The temperature of the punched porous straight cylindrical component is controlled within a second preset temperature range, and multiple passes of bulging-spinning composite forming are performed at this temperature until the component reaches the target curved surface profile. In each pass, the segmented die is first bulged to an intermediate target profile by driving the punch, and then the workpiece is spinned and shaped by a spinning wheel while the segmented die is kept expanded as an internal support, so that it fits the mold. Perform contour inspection on the formed components.

2. The multi-process composite forming method for porous conical curved surface components according to claim 1, characterized in that, The metal plate blank is a circular plate blank with a solid area without holes reserved in the middle. The diameter of the solid area is adapted to the inner diameter of the porous straight cylindrical component formed by deep drawing.

3. The multi-process composite forming method for porous conical curved surface components according to claim 2, characterized in that, The diameter of the solid region satisfies: , where d s Let d be the inner diameter of the porous straight cylindrical component. t k is the target diameter at one end of the porous conical cylinder component. t The safety factor ranges from 0.5 to 0.

8.

4. The multi-process composite forming method for porous conical curved surface components according to claim 1 or 2, characterized in that, The initial hole diameter and hole spacing on the metal plate blank are determined based on the target hole parameters of the porous conical cylinder component and calculated using a predetermined verification method to compensate for the deformation caused by subsequent deep drawing and bulging processes.

5. The multi-process composite forming method for porous conical curved surface components according to claim 4, characterized in that, The verification method includes: The proportionality coefficients of the influence of deformation on hole diameter and hole spacing are obtained through process simulation. The initial aperture and aperture spacing are calculated based on the influence ratio coefficient and the target aperture parameters.

6. The multi-process composite forming method for porous conical curved surface components according to claim 1, characterized in that, The number of lobes in the bulging mold is not less than 8.

7. The method according to claim 6, characterized in that, After the segmented mold is fully expanded, the gap between adjacent modules satisfies: t b ≤0.3 l b , where t b For the gap, l b This is the arc length of the working surface of a single segmented mold.

8. The method according to claim 1, characterized in that, The segmented mold is provided with a limiting structure to constrain the axial movement of the sheet metal during the bulging process.

9. The multi-process composite forming method for porous conical curved surface components according to claim 8, characterized in that, The limiting structure is a limiting plate, one end of which is provided with a hypotenuse, and the inclination angle α of the hypotenuse is in the range of 10° to 20°.

10. The multi-process composite forming method for porous conical curved surface components according to claim 1, characterized in that, The height of the segmented die is greater than the height of the porous straight cylindrical component formed by deep drawing.

11. The multi-process composite forming method for porous conical curved surface components according to claim 1, characterized in that, The segmented mold slides within a groove on the mold base via a slider at its bottom to achieve bulging and repositioning. The stroke of the slider satisfies the following: , where L h d represents the total stroke of the slider. t Let d be the target diameter at one end of the component. s The inner diameter is the porous straight cylindrical component.

12. The multi-process composite forming method for porous conical curved surface components according to claim 1, characterized in that, The contact height of the wheel surface is 3 to 6 times the original thickness of the metal plate blank.

13. The multi-process composite forming method for porous conical curved surface components according to claim 1, characterized in that, The total number of passes N in the bulging-spinning composite forming process is determined by the following formula: Where ceil is the floor function, and d t ds is the target diameter at one end of the component, r is the inner diameter of the porous straight cylindrical component, and r is the diameter bulging rate per pass, ranging from 5% to 10%.

14. The multi-process composite forming of porous conical curved surface components according to claim 8, characterized in that, The length of the segmented die relative to its bulging segmented die is 1.5 to 3 times the thickness of the original metal plate blank.

15. The multi-process composite forming method for porous conical curved surface components according to claim 9, characterized in that, The angle of the punch, the angle of the split die, and the tilt angle α are the same.

16. The multi-process composite forming method for porous conical curved surface components according to claim 5, characterized in that, The proportionality coefficients for the influence of deformation on the aperture and hole spacing obtained through process simulation include: The aperture on the flat blank is equal to the aperture on the porous conical part; The vertical spacing between the holes on the flat blank is equal to the vertical spacing between the holes on the multi-hole tapered cylinder part. The left-right spacing of the holes on the flat blank is equal to the left-right spacing of the holes on the multi-hole conical cylinder part; The deep drawing and bulging simulation is performed based on the initial porous flat blank drawing; The vertical and horizontal spacing of the porous holes in the final simulation results are measured to obtain the proportional coefficient of the influence of deformation on the hole diameter and its spacing.

17. The multi-process composite forming method for porous conical curved surface components according to claim 11, characterized in that, The segmented mold slides within a groove on the mold base via a slider at its bottom to achieve bulging and repositioning, including: A guide rod is provided in the groove, and an elastic element is sleeved on the guide rod. The split mold abuts against the guide rod.

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