High-temperature forming die for titanium alloy thin-wall part
By designing a high-temperature forming mold for titanium alloy thin-walled parts and using material flow to control the bosses and grooves, the wrinkles and cracks of large and complex titanium alloy thin-walled parts are solved, achieving overall high-quality forming, reducing costs and cycles.
Patent Information
- Application Number
- CN202510558575.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2025-07-01
AI Technical Summary
The prior art is difficult to accurately and with high quality to form large, curvature-variable and complex structures of titanium alloy thin-walled parts at high temperatures, which are prone to forming defects such as wrinkles and cracks, and traditional methods require disassembly into multiple parts to increase costs and cycles.
A high-temperature forming mold of titanium alloy thin-walled parts is designed, including upper and lower molds, material flow control bosses and grooves. By regulating the position and size of the device, the dynamic flow control of the material is realized to prevent wrinkles and cracks, and is formed using conventional equipment.
The overall high-quality forming of large and complex titanium alloy thin-walled parts is achieved, which improves the forming quality and accuracy, eliminates the need for special equipment research and development, and reduces costs and cycles.
Smart Images
Figure CN120228172A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a high-temperature forming die for titanium alloy thin-walled parts, belonging to the technical field of process equipment design and manufacturing. Background Art
[0002] Due to poor plastic forming performance at room temperature and easy generation of defects such as cracks, titanium alloy is generally plastically formed at high temperature. The hot forming temperature of titanium alloy is generally between 700°C and 800°C. The traditional forming method for titanium alloy thin-walled parts is to first place the coupled forming die in the forming equipment for heating. After the die temperature rises to the forming temperature and the temperature is uniform, load the titanium alloy sheet, heat the sheet for several minutes and then close the die for forming. This forming method is suitable for parts with single curvature, small size and small plastic deformation of materials. However, with the development of equipment such as aerospace, ordnance, ships and rail transit, more and more large-scale and integral complex titanium alloy thin-walled parts with irregular shapes and large curvature changes are used in equipment research and development. When such titanium alloy thin-walled parts are formed by traditional titanium alloy forming methods, forming defects such as wrinkling and cracking are likely to occur, and in severe cases, even the forming die may be damaged. If such thin-walled components are disassembled into multiple parts, it will increase the production process, cost and cycle, and at the same time, the forming quality is difficult to guarantee. How to achieve precise and high-quality forming of such titanium alloy thin-walled parts is a problem that needs to be solved urgently. Therefore, there is an urgent need for an innovative method and tooling for precise and high-quality forming of titanium alloy thin-walled parts at high temperature to achieve the integral, high-efficiency and precise forming of complex titanium alloy thin-walled components. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to provide a high-temperature forming die for titanium alloy thin-walled parts. The die design can be applied on conventional high-temperature plastic forming equipment for titanium alloy without the need to develop or purchase special equipment. At the same time, combined with the requirements of material flow during forming for the specific structural characteristics of titanium alloy components (thinning or thickening), relying on the design of special control devices on the die, dynamic flow control of titanium alloy materials during the forming process is realized, enabling the materials to flow purposefully and preventing defects such as cracking or wrinkling of titanium alloy thin-walled parts. The present invention can effectively improve the forming quality and accuracy of complex thin-walled components of titanium alloy. The specific content of the present invention is not limited to titanium alloy sheets, and is also applicable to complex thin-walled components formed from other materials at high temperature.
[0004] According to one aspect of the present application, there is provided a high-temperature forming die for titanium alloy thin-walled parts, which is composed of an upper die (1), a lower die (2), an upper template stock process allowance area (3), a lower template stock process allowance area (4), a material flow control boss (5), a material flow control groove (6), and an upper die extension boss (7).
[0005] The upper die (1) and the lower die (2) are provided with part profile areas with matching shapes for part forming.
[0006] Outside the part profile area of the upper die (1), there is an upper die blank process allowance area (3), and on the upper die blank process allowance area (3), there are material flow control bosses (5);
[0007] Outside the part profile area of the lower die (2), there is a lower die blank process allowance area (4), and on the lower die blank process allowance area (4), there are material flow control grooves (6).
[0008] The material flow control bosses (5) are arranged on one side or both sides of the part profile area of the upper die (1), and are specifically determined according to the part structure characteristics and the material flow trend during forming.
[0009] The positions of the material flow control bosses (5) correspond to those of the material flow control grooves (6), and their shapes match. When the upper die (1) and the lower die (2) are closed, the material flow control bosses (5) fall into the material flow control grooves (6), but there is a gap δ between the material flow control bosses (5) and the material flow control grooves (6).
[0010] The material flow control bosses (5) are arranged at the corresponding positions of the parts where wrinkles are likely to occur during the forming of the part structure characteristics, and at the same time avoid the parts where the part structure characteristics are likely to rupture during forming.
[0011] The material flow control grooves (6) penetrate the lower die (2) horizontally to prevent the material from being subjected to strong tensile stress due to the closed structure, resulting in material rupture.
[0012] The gap δ follows the following formula:
[0013] δ = 1.1 × t
[0014] where t is the part thickness.
[0015] The cross-section of the material flow control bosses (5) is rectangular or semi-circular, and the cross-section at any place has the same shape and size, and the edges are rounded. The R of the rounded corners is designed according to the following formula:
[0016] R = (D - 10) ÷ 2;
[0017] In the formula, D is the cross-section width;
[0018] If D is less than 10 mm, then R = D ÷ 2;
[0019] The bottom edge of one side of the material flow control boss (5) close to the part profile area of the upper die (1) is parallel to the bottom edge of the part profile area of the upper die (1) close to the material flow control boss (5), and the distance L 调 is:
[0020]
[0021] where h 传 is the height between the upper and lower dies when wrinkles appear during the traditional coupled-mode forming process, h 传 can be determined by forming simulation. When using a traditional coupled die for forming simulation, when wrinkles begin to appear in the material during the simulation, the height between the upper and lower dies is h 传 , and α is the acute angle formed by the part profile area of the upper die (1) near the material flow control boss (5) and the bottom surface of the die. By calculating the maximum acute angle α 大 and the minimum acute angle α 小 , the position of the boss can be obtained according to the above formula.
[0022] The length of the material flow control boss (5) should be at least 3 mm to 5 mm longer than the length of the wrinkling-prone part on both sides when the part structure features are formed;
[0023] The height h of the material flow control boss (5) should be designed according to the following formula:
[0024] h = h 传 +(3 mm to 5 mm);
[0025] The part profile area of the upper die (1) is provided with an upper die extension boss (7) along the easily cracked end of the part. The ridge line of the upper die extension boss (7) is parallel to the plane of the process allowance area (3) of the upper template material. The function of the upper die extension boss (7) is to guide the forward extension of the easily cracked area and prevent cracking defects from occurring in the effective area of the part during forming.
[0026] According to another aspect of the present application, there is provided a process method for forming a titanium alloy thin-walled part using a mold that dynamically adjusts the material flow and suppresses defects during the high-temperature forming process of the titanium alloy thin-walled part, using the above-mentioned high-temperature forming mold for titanium alloy thin-walled parts.
[0027] 1) The length dimension L of the sheet material required for forming is designed according to the following formula:
[0028] L = L 型 + L 调 + L 凹 +(50 - 80 mm)
[0029] where L 型 is the length of the developed material at the part profile of the lower die 2, and L 凹 is the perimeter of the cross-section of the material flow control groove. An additional allowance of (50 - 80 mm) is added according to the complexity of the part to supplement the material flow.
[0030] 2) During forming, as the upper die moves downward, the material flow control boss 5 gradually falls into the material flow control groove 6. The sheet metal process margin area loaded between the two will be clamped by the two, thereby stretching the sheet metal in the corresponding part forming area of this part, preventing the material from accumulating in the corresponding part forming area, and further preventing the generation of wrinkles in this part.
[0031] 3) At the same time, the material in the extension boss 7 area will gradually thin due to the small bending radius. After thinning, due to the friction and interference between the material and the die, etc., it will effectively inhibit the thinning of the material at the easily cracked end of the part and prevent the occurrence of cracking defects.
[0032] 4) After forming, heat preservation and pressure holding, the part can be taken out, and the sheet metal process margin area can be cut off, and the final part can be cut out according to the theoretical shape.
[0033] The process method and die design for dynamically regulating material flow and inhibiting defect generation during the hot forming of titanium alloy thin-walled parts provided by the present invention can design a control device on the tooling according to the structural characteristics of the component and the material flow trend during forming. By reasonably designing the size and position distribution of the control device, directional elimination control is carried out on the instability wrinkling area to prevent the generation of wrinkle defects. At the same time, it can also ensure that there is enough material for supplement at the easily cracked place to prevent local cracking. The present invention can realize the overall high-quality precise forming of titanium alloy thin-walled parts with large size, variable curvature and complex structural characteristics, and strongly support the research, development and iterative upgrade of various complex equipment. At the same time, this die design and process method can realize the high-quality forming of titanium alloy thin-walled parts without using special dedicated equipment, and there is no need for additional equipment research and development and investment. Description of the Drawings
[0034] Figure 1 Schematic diagram of the integral complex titanium alloy thin-walled part to be prepared in Example 1;
[0035] Figure 2 Schematic diagram of the upper die;
[0036] Figure 3 Schematic diagram of the lower die;
[0037] Figure 4 Schematic diagram of the material flow control boss;
[0038] Figure 5 Schematic diagram of the material flow control groove;
[0039] Figure 6 Schematic diagram of the extension boss.
[0040] Among them, 1 is the upper die, 2 is the lower die, 3 is the upper die sheet metal process margin area, 4 is the lower die sheet metal process margin area, 5 is the material flow control boss, 6 is the material flow control groove, and 7 is the upper die extension boss. Detailed Embodiments
[0041] The following further describes the detailed embodiments of the present invention in conjunction with the accompanying drawings. The following examples are used to illustrate the present invention but not to limit the application scope of the present invention.
[0042] Example 1
[0043] Prepare an integrated complex titanium alloy thin-walled part as Figure 1 shown.
[0044] The mold mainly includes an upper mold 1, a lower mold 2, an upper template stock process allowance area 3, a lower template stock process allowance area 4, a material flow control boss 5, a material flow control groove 6, and an upper mold extension boss 7.
[0045] Among them, the upper mold 1 and the lower mold 2 adopt a coupled mold design method in the part profile area.
[0046] Among them, on both sides of the part profile area of the upper mold 1, an upper template stock process allowance area 3 is designed, and a material flow control boss 5 is designed on the upper template stock process allowance area 3.
[0047] Among them, the material flow control boss 5 can be designed on one side or both sides of the upper template stock process allowance area 3 according to the part structure characteristics and the material flow trend during forming. In this embodiment, in order to ensure that the wrinkle defect can be fully eliminated, the control bosses 5 are designed on both sides respectively.
[0048] Among them, the material flow control boss 5 is designed at the corresponding position of the part structure feature where wrinkling is likely to occur during forming, and at the same time, the position where the part structure feature is likely to crack during forming is avoided.
[0049] Among them, the cross-section of the material flow control boss 5 can be designed as a rectangle or a semicircle, and the edge of the material flow control boss 5 is chamfered with a fillet. The fillet R is designed according to the following formula:
[0050] R = (D - 10) ÷ 2
[0051] In the formula, D is the cross-section width. If D is less than 10 mm, then R is designed with the maximum possible design amount. In this embodiment, the initial designed cross-section width of the material flow control boss 5 is 40 mm, and the edge chamfer R is 15 mm.
[0052] The bottom edge of the side of the material flow control boss (5) close to the part profile area of the upper mold (1) is parallel to the bottom edge of the part profile area of the upper mold (1) close to the material flow control boss (5), and the distance L 调 is:
[0053]
[0054] In the formula, h传 During the traditional coupled die forming process, when wrinkles appear, the height h between the upper die and the lower die 传 can be determined through forming simulation. When using a traditional coupled die for forming simulation, when wrinkles begin to appear in the material during the simulation process, the height between the upper die and the lower die is h 传 , α is the acute angle formed by the part profile area of the upper die (1) near the material flow control boss (5) and the bottom surface of the die. By calculating the maximum acute angle α formed by this part profile area and the bottom surface of the die 大 and the minimum acute angle α 小 , the position of the boss can be obtained according to the above formula. In this embodiment, according to the traditional coupled die for forming simulation, it is found that when the height between the upper die and the lower die is 45 mm, the material shows a tendency to wrinkle, then h 传 is 45 mm, the minimum acute angle formed by the wrinkled part of the part and the bottom surface of the die is 45°, and the maximum is 73°, then 13.76 mm ≤ L 调 ≤ 45 mm, L 调 can take 45 mm.
[0055] Among them, the outer contour of the material flow control boss 5 should be consistent with the outer contour of the part profile of the upper die, and the length should exceed the length of the part structure feature prone to wrinkling during forming, with both sides being 3 mm - 5 mm long respectively.
[0056] Among them, the height h of the material flow control boss 5 should be designed according to the following formula:
[0057] h = h 传 +(3 mm - 5 mm)
[0058] In this embodiment, h 传 is 45 mm, then h takes 50 mm.
[0059] Among them, an extended boss 7 is designed along the part profile area of the upper die 1 at the end of the part prone to cracking. The ridge line of the extended boss 7 is parallel to the plane of the process allowance area 3 of the upper template material. The function of this extended boss 7 is to guide the front extension of the prone-to-crack area and prevent cracking defects from occurring in the effective area of the part during forming.
[0060] Among them, on the lower die 2, material flow control grooves 6 are designed at the corresponding positions of the material flow control bosses 5 of the upper die 1. The material flow control bosses 5 and the material flow control grooves 6 are designed in a coupled mode. When the upper die 1 and the lower die 2 are closed, the material flow control bosses 5 fall into the material flow control grooves 6.
[0061] Among them, the material flow control grooves 6 are designed in a through form to prevent strong tensile stress on the material caused by a closed structure, resulting in material rupture.
[0062] Among them, the gap δ between the material flow control boss 5 and the material flow control groove 6 is designed according to the following formula:
[0063] δ = 1.1×t
[0064] Where t is the material thickness. In this embodiment, the thickness of the raw material is 1.6 mm, so δ = 1.76 mm.
[0065] During the high-temperature forming process of the above titanium alloy thin-walled parts, the process method for forming titanium alloy thin-walled parts by dynamically adjusting the material flow and suppressing defects using the mold is as follows:
[0066] 1) The length dimension L of the sheet metal required for forming is designed according to the following formula:
[0067] L = L 型 + L 调 + L 凹 +(50 - 80 mm)
[0068] In the formula, L 型 is the length of the developed material at the part surface of the lower die 2, and L 凹 is the perimeter of the cross-section of the material flow control groove. An additional allowance of (50 - 80 mm) is added according to the complexity of the part to supplement the material flow. In this embodiment, the length L 型 of the developed material at the part surface of the lower die 2 is 623 mm, L 调 is 45 mm, and L 凹 is 140 mm. Since the material flow control bosses 5 are provided on both sides of the mold,
[0069] then L = 623 + 45×2 + 140×2 + 50 = 1043 mm. For the convenience of cutting the raw material, L is taken as 1050 mm.
[0070] 2) During forming, place the mold on the heating platform of a conventional hot forming equipment, heat the mold to the forming temperature, and keep it warm for a period of time to make the mold temperature uniform.
[0071] 3) After the mold temperature is uniform, place the sheet metal on the lower die, and then start closing the mold.
[0072] 4) As the upper die moves down, the material starts to flow unevenly along with the part and mold structure features. The material in the small bending radius part thins, and the material in the parts with concave and other material receiving parts thickens.
[0073] 5) When the material flow control boss 5 just falls into the material flow control groove 6, the process allowance part of the sheet metal loaded between the two will be clamped by the two, so as to stretch the sheet metal in the corresponding part forming area of the part, prevent the material from accumulating in the corresponding part forming area, and further prevent the generation of wrinkles in this part.
[0074] 6) Meanwhile, due to the small bending radius, the material at the extended boss 7 will gradually thin out. After thinning, due to the friction and interference between the material and the mold, it will effectively inhibit the thinning of the material at the easily cracked end of the part and prevent the occurrence of cracking defects.
[0075] 4) After the mold closing is completed, the part can be taken out after holding the pressure for a certain time while maintaining the temperature, and the process allowance area of the sheet metal is cut off, and the final part is cut out according to the theoretical contour.
[0076] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can make several modifications or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims
1. A high temperature forming die for titanium alloy thin-walled parts, characterized in that: The mold comprises an upper mold (1), a lower mold (2), an upper mold material process margin area (3), a lower mold material process margin area (4), a material flow regulating boss (5), a material flow regulating groove (6), and an upper mold extension boss (7).
2. The high temperature forming die for titanium alloy thin-walled parts according to claim 1, characterized in that: The upper die (1) and the lower die (2) are provided with part profile areas with matching shapes for forming parts.
3. The high temperature forming die for titanium alloy thin-walled parts according to claim 2, characterized in that: An upper mold plate material process margin area (3) is provided outside the part molding surface area of the upper mold (1), and a material flow regulating boss (5) is provided on the upper mold plate material process margin area (3); A lower template material process margin area (4) is provided outside the part profile area of the lower mold (2), and a material flow regulating groove (6) is provided on the lower template material process margin area (4).
4. The high temperature forming die for titanium alloy thin-walled parts according to claim 3, characterized in that: The material flow regulating boss (5) is arranged on one side or both sides of the part molding surface area of the upper mold (1), and is specifically determined according to the structural characteristics of the part and the material flow trend during molding.
5. The high temperature forming die for titanium alloy thin-walled parts according to claim 4, characterized in that: The material flow regulating boss (5) corresponds to the material flow regulating groove (6) in position and has matching shape. When the upper mold (1) and the lower mold (2) are molded together, the material flow regulating boss (5) falls into the material flow regulating groove (6), but a gap δ exists between the material flow regulating boss (5) and the material flow regulating groove (6).
6. The high temperature forming die for titanium alloy thin-walled parts according to claim 5, characterized in that: The material flow regulating boss (5) is arranged at a position corresponding to a part that is prone to wrinkling when the structural feature of the part is formed, while avoiding a part that is prone to rupture when the structural feature of the part is formed.
7. The high temperature forming die for titanium alloy thin-walled parts according to claim 6, characterized in that: The material flow regulating groove (6) passes through the lower die (2) transversely, thereby preventing the closed structure from causing strong tensile stress on the material, thereby preventing the material from breaking.
8. The high temperature forming die for titanium alloy thin-walled parts according to claim 5, characterized in that: The gap δ complies with the following formula: δ = 1.1 × t; Where t is the part thickness.
9. The high temperature forming die for titanium alloy thin-walled parts according to claim 7, characterized in that: The cross section of the material flow regulating boss (5) is rectangular or semicircular, and the cross section at any point has the same shape and size, and the edge is rounded. The R of the rounded corner is designed according to the following formula: R = (D-10) ÷ 2; Where D is the cross-sectional width; If D is less than 10 mm, then R = D ÷ 2; The bottom edge of one side of the material flow regulating boss (5) close to the part profile area of the upper die (1) is parallel to the bottom edge of the part profile area of the upper die (1) close to the material flow regulating boss (5), and the distance L 调 for: Where h 传 The height between the upper and lower dies when wrinkles appear in the traditional coupled die forming process, h 传 It can be determined by forming simulation. Using traditional coupled molds for forming simulation, when the material begins to wrinkle during the simulation, the height between the upper and lower molds is h. 传 α is the acute angle between the part profile area of the upper die (1) near the material flow regulating boss (5) and the bottom surface of the die. By calculating the maximum acute angle α between the part profile area and the bottom surface of the die 大 and the minimum acute angle α 小 , according to the above formula, the boss position can be obtained; The length of the material flow regulating boss (5) should be at least 3 mm to 5 mm longer on both sides than the length of the part that is prone to wrinkling during the forming of the structural features of the part; The height h of the material flow regulating boss (5) should be designed according to the following formula: h=h 传 +(3mm~5mm)。 10. The high temperature forming die for titanium alloy thin-walled parts according to claim 7, characterized in that: The upper die (1) is provided with an upper die extension boss (7) along the easily-fragile end of the part in the part molding surface area, the ridge line of the upper die extension boss (7) is parallel to the plane of the upper die plate material process margin area (3), and the function of the upper die extension boss (7) is to guide the easily-fragile area to extend forward, so as to prevent fracture defects from occurring in the effective area of the part during forming.