Forging and pressing die for metal forge piece and die design method

Abstract

The invention relates to the field of dies, in particular to a forging die for a metal forge piece and a die design method.The metal forge piece is in a hollow cone shape and comprises a flange plate and a conical face located on the flange plate, and a through hole is formed in the conical face; the forging and pressing die comprises a female die and a male die which are oppositely arranged, forging and pressing protrusions are arranged on the female die and / or the male die, the height of the forging and pressing protrusions is 13-17 mm, and the hole diameter of the through hole is smaller than the diameter of the forging and pressing protrusions. According to the method, the average deformation, the underpressure value and the curved surface thickness of the forge piece can be effectively controlled to reach the ideal value range, the forging protrusions extrude materials in the forming process, more flange plate materials of the forge piece flow in, forming is more sufficient, and therefore it is ensured that the forge piece is formed in place, and meanwhile materials are saved.

Description

Technical Field

[0001] The invention relates to the field of dies, in particular to a forging die for a metal forging and a die design method. Background Art

[0002] With the rapid development of the global manufacturing industry, the market demand for forging dies has shown a sustained growth trend. This growth trend is particularly evident in several key areas, especially in the automotive, aerospace, and energy fields. The increasing demand for high-performance die forgings in these industries has not only promoted the vigorous development of related manufacturing industries, but also become an important driving force for the sustained growth of the forging die industry. In order to meet the strict requirements of these industries for high precision, high strength and high reliability of forging dies, die manufacturing companies have increased their investment in technology research and development and innovation, and continuously improved their own technical level and product quality. For the forging process of aluminum alloy sealing cover, there are mainly two kinds of forging dies in the existing traditional dies. The first kind of dies is as follows: Figure 6 As shown in a, the upper die is a male die and the lower die is a female die. The forming simulation is performed by using SIMUFACT FORMING software. Figure 6 As shown in Figure b, during the forging process, the contact area between the blank and the upper die is larger. In the high-temperature die, the blank is easy to adhere to the upper die, making it difficult to demold the workpiece, and it is difficult to ensure the appropriate posture and position of the blank when placed in the die.

[0003] The second mold is Figure 7 As shown in a, the upper die is a concave die, and the lower die is a convex die. The forming simulation is as follows: Figure 7 As shown in b, during the forging process, the material will flow in two directions, namely, the through hole and the flange, resulting in insufficient material flowing to the forging flange, causing the flange to be not formed in place, and the punch has no positioning structure, resulting in inaccurate positioning of the blank.

[0004] The three forging parameters, namely, the average deformation of forgings, the underpressure value and the thickness of forging surface, are important standards for measuring the production quality of metal forgings. The average deformation of forgings is the average deformation of each part of the forging after forming. If the average deformation of forgings is too large, the internal grains of the forgings will change, which will reduce the strength of the forgings. If the average deformation of forgings is too small, the material utilization rate will not be high, which will waste materials. The underpressure value refers to the distance between the upper and lower dies after the forgings are formed. When the flange is fully formed, the lower the underpressure value, the higher the material utilization rate. The thickness of forging surface refers to the thickness of the forging surface after the forging is formed. If the thickness of the forging surface is too large, the material utilization rate will be low. If the thickness of the forging surface is too small, it will be difficult to process and affect the qualified rate of forgings. When the existing mold is forging metal forgings with flanges, the three forging parameters will affect each other. When adjusting one of the parameters by adjusting the mold parameters, the other two parameters will deviate from the ideal values. For example, if the underpressure value is adjusted to a smaller value, the average deformation of the forging will inevitably increase and the thickness of the forging surface will decrease. Therefore, it is extremely difficult for traditional molds to control the three forging parameters at the same time by adjusting the mold.

[0005] When designing a mold, technicians will pursue the ideal value range of these three forging parameters as a standard for measuring the quality of the mold, that is, the average deformation of the forging is 50%-70%, the underpressure value is about 0.5 times the product thickness, and the forging surface thickness is 2-7 mm larger than the product thickness as a processing allowance (the theoretical value range is the optimal range under the mutual influence of the three forging parameters). Only when the forging parameters are within the above ideal value range can the mold ensure that the forging is formed in place and minimize the waste of raw materials. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a forging die and die design method for metal forgings, which can effectively control the average deformation, underpressure value and curved surface thickness of the forgings to reach an ideal value range. The forging protrusion squeezes the material during the forming process, so that more flange material of the forging flows in and the forming is more complete, thereby ensuring that the forgings are formed in place while saving materials.

[0007] The specific technical scheme of the present invention is as follows: a forging die for a metal forging, wherein the shape of the metal forging is a hollow cone, including a flange and a conical surface located on the flange, and a through hole is arranged on the conical surface; the forging die includes a die and a punch arranged opposite to each other, and a forging protrusion is arranged on the die and / or the punch, and the height of the forging protrusion is 13-17 mm, and the aperture of the through hole is smaller than the diameter of the forging protrusion.

[0008] Furthermore, the outer edges of the concave die and the convex die are planes, and after forging, a space for accommodating the flange is formed in the two planes.

[0009] Furthermore, a guide outer wall is disposed on the periphery of the plane of the male mold, and a corresponding guide inner wall is disposed on the periphery of the plane of the female mold.

[0010] Preferably, a forging protrusion is provided on the die.

[0011] Preferably, a positioning protrusion is provided on the male mold, and the positioning protrusion can be accommodated in the through hole.

[0012] Furthermore, a receiving groove is provided on the outer periphery of the forging protrusion, and the receiving groove is provided between the forging protrusion and a forming inclined surface of the die for forming a metal forging, and the receiving groove includes a first forming surface, a second forming surface and a forming inclined surface connected in sequence, and the first forming surface is connected to the forging protrusion.

[0013] Preferably, the width of the second profile is 18-22 mm, and the angle between the first profile and the second profile is 120°-130°.

[0014] The present invention also provides a die design method for a forging die of a metal forging, comprising the following steps: S1: blank selection: select a blank to perform a hot compression test, obtain performance parameters of the blank, and input the performance parameters of the blank into a computer simulation software.

[0015] S2: Preliminary drawing and design of the mold: Use computer 3D drawing software to design the punch and die according to the workpiece drawing, and design a forging protrusion in the middle of the punch and / or die.

[0016] S3: Die forming simulation: Import the die designed in S2 into the computer simulation software, set the die forging parameters, input the performance parameters of the billet and the forging deformation calculation formula, and then perform die forming simulation on the computer to obtain the forging parameters, which are the average deformation of the forging, the underpressure value and the forging surface thickness.

[0017] S4: Die and blank adjustment: Compare the forging parameters obtained in S3 with the ideal values, and adjust the shape of the forging protrusion, the width of the second profile, and the angle between the first profile and the second profile according to the parameter comparison results.

[0018] S5: Repeat S3 and S4 until the forging parameters reach the ideal values ​​and the optimal die parameters are obtained.

[0019] Furthermore, in S3, the calculation formula for the forging deformation is: , is the equivalent plastic strain.

[0020] Furthermore, in S3, the die forging parameters set are the die and blank temperature, the friction coefficient between the die and the blank, the upper die downward distance, and the maximum stop pressure of the die.

[0021] Compared with the prior art, the present invention has the following beneficial effects: Firstly, the present invention provides a forging protrusion in the die, and the forging protrusion squeezes the material during the forming process to prevent the material from flowing toward the inner hole of the forging, so that more material flows into the flange of the forging, and the flange is formed more fully, thereby ensuring that the forging is formed in place while saving material to a great extent; in addition, the height of the forging protrusion is 13-17 mm and the diameter of the forging protrusion is larger than the aperture of the through hole, so that the forging protrusion can be pressed on the blank and effectively squeeze the metal material to flow toward the conical surface and the flange, thereby ensuring the smooth forming of the forging.

[0022] Secondly, by adjusting the width of the second molding surface and the angle between the first molding surface and the second molding surface, the present invention can more easily and effectively control the average deformation of the forging, the underpressure value and the thickness of the forging surface to be within the ideal value range, thereby reducing the difficulty of mold structure design and the workload of subsequent mold debugging.

[0023] Thirdly, the accommodating groove on the outer periphery of the forging protrusion can accommodate excess material after the forging is formed, further reducing the underpressure value of the forging and the thickness of the forging surface, and avoiding the accumulation of excess material on the forging forming surface to have an adverse effect on the forging. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a product in an embodiment of the present invention; Figure 2 A schematic cross-sectional view of a mold structure according to an embodiment of the present invention; Figure 3 It is a schematic diagram of the structure of the forging protrusion and the accommodating groove in the die of an embodiment of the present invention; Figure 4 A computer simulation diagram of a mold forming according to an embodiment of the present invention; Figure 5 It is a computer simulation forming diagram of different forging protrusion heights in the embodiment of the present invention; in, Figure 5 a is a computer simulation forming diagram when the forging protrusion height is 12 in the embodiment of the present invention, Figure 5 b is the computer simulation forming diagram when the forging protrusion height is 13. Figure 5 c is a computer simulation forming diagram of the embodiment of the present invention when the forging protrusion height is 17, Figure 5 d is a computer simulation forming diagram when the forging protrusion height is 18 in the embodiment of the present invention; Figure 6 It is a schematic diagram of the first mold structure and simulation molding in the prior art; in, Figure 6a is a schematic diagram of the first mold structure in the prior art, Figure 6 b is a schematic diagram of the first computer simulation molding; Figure 7 It is a schematic diagram of the second mold structure and simulation molding in the prior art; in, Figure 7 a is a schematic diagram of the second mold structure in the prior art, Figure 7 b is a schematic diagram of the second computer simulation molding; In the figure: 1. die; 101. guide inner wall; 102. forming slope; 103. accommodating groove; 1031. first molding surface; 1032. second molding surface; 2. punch; 201. guide outer wall; 3. metal forging; 301. through hole; 302. conical surface; 303. flange; 4. forging protrusion; 5. positioning protrusion. DETAILED DESCRIPTION

[0025] To make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them.

[0026] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents some embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Example

[0027] A forging die for metal forgings, see Figure 1 and Figure 2The metal forging 3 is in the shape of a hollow cone, including a flange 303 and a conical surface 302 located on the flange 303, and a through hole 301 is provided on the conical surface 302; the forging die includes a die 1 and a punch 2 arranged oppositely, and a forging protrusion 4 is provided on the die 1, and the height of the forging protrusion 4 is 13-17 mm, and the aperture of the through hole 301 is smaller than the diameter of the forging protrusion 4. The forging protrusion 4 squeezes the material during the forming process, preventing the material from flowing toward the inner hole of the forging, so that more material flows into the flange 303 of the forging, and the forming of the flange 303 is more sufficient, thereby ensuring that the forging is formed in place and saving materials to a great extent; the height of the forging protrusion 4 is 13-17 mm and the diameter of the forging protrusion 4 is larger than the aperture of the through hole 301, so that the forging protrusion 4 can be pressed on the blank and effectively squeeze the metal material to flow toward the conical surface 302 and the flange 303, thereby ensuring the smooth forming of the forging. In addition, in this embodiment, the concave die 1 is used as the upper die and the convex die 2 is used as the lower die, so that the forging can be easily removed from the die after the forming is completed.

[0028] The outer edges of the concave die 1 and the convex die 2 are planes, and after forging, a space for accommodating the flange 303 is formed in the two planes. The arrangement of the forging protrusion 4 enables the metal material to flow more toward the conical surface 302 and the flange 303 under the extrusion of the forging protrusion 4 during the forging process of the die, until the entire accommodating space for accommodating the flange 303 is filled, thereby promoting the forming of the flange 303 of the metal forging 3 in place.

[0029] In this embodiment, the outer periphery of the plane of the punch 2 is provided with a guide outer wall 201, and the outer periphery of the plane of the die 1 is provided with a corresponding guide inner wall 101. The forming force of the forging die is huge, and the reaction force generated by the forging is also very huge. When the die moves downward, the reaction force acting on the upper die may cause the die 1 to shift during the forming process, causing the forging to deform or even damage the die profile. In this embodiment, the guide inner wall 101 and the guide outer wall 201 of the die 1 cooperate with each other to fix and guide the downward direction of the die, and apply the huge reaction force to the die body, so as to avoid the deviation of the die 1 under the constraint of the die body, thereby facilitating better forming of the forging.

[0030] In this embodiment, a positioning protrusion 5 is provided on the punch 2, and the positioning protrusion 5 can be accommodated in the through hole 301. When the die produces the metal forging 3, the blank is placed on the punch 2, and the positioning protrusion 5 is accommodated in the through hole 301 to fix the offset of the blank on the XY plane, so that the blank can be quickly positioned in the die, and the feeding is simpler and faster, which avoids the blank from moving due to the influence of the die force during the downward movement of the die, further improves the forming performance of the forging, and avoids defects such as deformation and cracking of the forging.

[0031] Furthermore, if Figure 3 As shown, the outer periphery of the forging protrusion 4 is provided with a receiving groove 103, which is provided between the forging protrusion 4 and the forming inclined surface 102 of the die for forming the metal forging 3, and the receiving groove 103 includes a first profile 1031, a second profile 1032 and the forming inclined surface 102 connected in sequence, and the first profile 1031 is connected to the forging protrusion 4. The receiving groove 103 can accommodate metal materials during the die forming process, and the metal materials will flow more to the flange 303 under the extrusion of the first profile 1031 and the second profile 1032 and the constraint of the forming inclined surface 102, further promoting the forming of the flange 303; and at the end of the forming process, the flange 303 is formed in place, and the excess material will be accumulated in the receiving groove 103 under the influence of pressure, further reducing the underpressure value of the forging and the thickness of the forging curved surface, and avoiding the accumulation of excess material on the forging forming surface to have an adverse effect on the forging.

[0032] After die design and forming simulation, in this embodiment, the width of the second profile 1032 in the forging die is preferably 18-22 mm, and the angle between the first profile 1031 and the second profile 1032 is preferably 120°-130°. When the width of the second profile 1032 of the forging die and the angle between the first profile 1031 and the second profile 1032 are both within this preferred range, the average deformation of the forging, the underpressure value and the thickness of the forging curved surface can be effectively controlled within the ideal value range pursued by the technicians, and the blank material utilization rate can be improved as much as possible while promoting the forming of the forging flange 303.

[0033] The three forging parameters, namely, the average deformation of the forging, the underpressure value and the thickness of the forging surface, are important standards for measuring the production quality of metal forgings 3. The average deformation of the forging is the average deformation of each part of the forging after forming. If the average deformation of the forging is too large, the internal grains of the forging will change, which will reduce the strength of the forging; if the average deformation of the forging is too small, the material utilization rate will not be high, which will waste materials. The underpressure value refers to the distance between the upper and lower dies after the forging is formed. When the flange 303 is fully formed, the lower the underpressure value, the higher the material utilization rate. The thickness of the forging surface refers to the thickness of the forging surface after the forging is formed. If the thickness of the forging surface is too large, the material utilization rate will be low. If the thickness of the forging surface is too small, it will be difficult to process and affect the qualified rate of the forging. These three forging parameters will affect each other. When adjusting one of the parameters by adjusting the mold parameters, the other two parameters will deviate from the ideal values. For example, if the underpressure value is adjusted to a smaller value, the average deformation of the forging will increase and the thickness of the forging surface will decrease. Therefore, it is extremely difficult for traditional molds to control these three forging parameters at the same time by adjusting the mold.

[0034] When designing and debugging the mold, the technicians adjust the mold through various means to pursue the ideal value range of the three forging parameters, namely the average deformation of the forging, the underpressure value and the forging surface thickness, as the standard for measuring the quality of the mold, that is, the average deformation of the forging is 50%-70%, the underpressure value is about 0.5 times the product thickness, and the forging surface thickness is 2-7 mm larger than the product thickness as the processing allowance (the theoretical value range is the optimal range under the mutual influence of the three forging parameters). Only when the forging parameters are within the above ideal value range can the mold ensure that the forging is formed in place and minimize the waste of raw materials.

[0035] In this embodiment, the thickness of the forging product is 15 mm, so the ideal value range is that the average deformation of the forging is 50%-70%, the underpressure value is ≤8, and the thickness of the forging surface is 17-22 mm. Only when the forging parameters are within the above ideal value range, the mold of this embodiment can ensure that the forging is formed in place and minimize the waste of raw materials.

[0036] In this embodiment, if Figure 3 As shown, the width of the second molding surface 1032 of the mold is set to A value, and the angle between the first molding surface 1031 and the second molding surface 1032 is set to B value, and a computer molding simulation test is performed, and the results are as follows: The heights of the forging protrusions 4 are set to 12, 13, 17, and 18 mm respectively, and the other factors remain the same to perform forging simulation. In this embodiment, the height of the forging protrusions 4 is set in the range of 13-17 mm. Figure 5 The simulation results are shown in the following table. If the height of the forging protrusion 4 is less than 13 mm, the average deformation of the forging will increase and the strength of the forging will be insufficient. If the height of the forging protrusion 4 is higher than 17 mm, the material cannot be squeezed into the flange 303 and the forging cannot be formed.

[0037]

[0038] In this embodiment, the height of the forging protrusion 4 is set to 15 mm, and the A value of the simulation test is 18-22 mm, and the B value is 120°-130°.

[0039] Set A=18mm, adjust B value, and perform forming simulation. The results are as follows:

[0040] Set A=20 mm, adjust B value, and perform forming simulation. The results are as follows:

[0041] Set A=22mm, adjust B value, and perform forming simulation. The results are as follows:

[0042] It can be seen that when the A value is 18-22 mm and the B value is 120°-130°, the average deformation, underpressure value and forging surface thickness of the forging are all within the ideal value range. When A is 20 mm and B is 120°, the forging surface thickness is the smallest, which saves the most material and has the best effect.

[0043] The embodiment of the present invention further provides a method for designing a forging die. The die design process requires the use of two computer softwares, SOLIDWORKS (a computer three-dimensional drawing software) and SIMUFACT FORMING (a computer die forming simulation software), which specifically includes the following steps: S1: blank selection: In this embodiment, 2195 aluminum-lithium alloy is selected as the blank, and a hot compression test is performed on the 2195 aluminum-lithium alloy to obtain material performance parameters, such as thermal conductivity, specific heat capacity, material density, Young's modulus, Poisson's ratio and thermal expansion coefficient, etc., which are input into SIMUFACT FORMING software, and a material database for 2195 aluminum-lithium alloy is established in SIMUFACT FORMING.

[0044] S2: Preliminary drawing design of mold: Use SOLIDWORKS software to design the mold structure according to the workpiece drawing, design the forging mold structure diagram as mentioned above, and import the mold structure diagram into SIMUFACT FORMING software.

[0045] S3: Die forming simulation: In SIMUFACT FORMING software, set the die temperature to 460 degrees, the blank temperature to 480 degrees, the friction coefficient at the contact between the blank and the die to 0.3, set the upper die pressing distance to 129.2 mm, the maximum die stop pressure to 12000t, and then input the blank parameters such as the original thickness of 33, the outer diameter of 750 mm, and the inner diameter of 380 mm and the forging deformation calculation formula (EFFPLS is the equivalent plastic strain), then start SIMUFACT FORMING software to simulate the die forming process and obtain forging parameters such as the average deformation of the forging, underpressure value, and forging surface thickness.

[0046] S4: Die and billet adjustment: According to the comparison between the forging parameters obtained in S3 and the ideal values, the ideal values ​​in this embodiment are that the forging surface thickness is 50-70%, the average deformation of the forging is 17-22 mm, and the underpressure value is less than or equal to 8. According to the parameter comparison results, the shape of the forging protrusion 4, the width of the second die surface 1032, the angle between the first die surface 1031 and the second die surface 1032, and the billet parameters are adjusted.

[0047] S5: Repeat S3 and S4 until the forged flange 303 fills the flange accommodation space. Figure 4 As shown, the forging parameters are within the ideal value range, and the optimal die parameters and billet parameters are obtained.

[0048] In this embodiment, the fixed blank parameters are blank thickness of 35 mm, outer diameter of 800 mm, and inner diameter of 400 mm.

[0049] In S3 of this embodiment, the values ​​of A and B are adjusted, and the forging parameter results are shown as follows. The die forming is simulated by controlling the variables separately to obtain the simulation results: Set A to 48 mm and adjust the value of B to get the following result:

[0050] Set A to 5 mm and adjust the value of B to get the following result:

[0051] (3) Set A to 20 mm and adjust the value of B to obtain the following results:

[0052] Analysis of simulation results: When the A value is increased, the flange cannot be formed in place, and the underpressure value is high, the average deformation of the forging is low, the thickness of the forging surface is large, and material will be wasted; when the A value is reduced, the flange is easy to form, but the underpressure is high, the deformation is too high, the thickness of the forging surface is large, and material will be wasted. When the A value remains unchanged and the B value is reduced, the force in the forming direction cannot be generated, resulting in large deformation of the surface and high underpressure; when the B value is increased, the material flows to the center of the two grooves, resulting in small deformation at the surface.

[0053] After simulation, the flange 303 of the final forging of this embodiment is fully filled, the forging surface thickness is 17.7 mm, the underpressure value is 7.15 mm, and the average deformation of the forging is 17.7 mm, which is within the ideal value range, thereby obtaining the preferred solution with mold parameters of A being 20 mm, B being 120 degrees, and blank parameters of 35 mm thickness, 800 mm outer diameter, and 400 mm inner diameter.

[0054] The production process of the metal forging 3 in this embodiment is as follows: blanking an aluminum alloy plate of Φ800×34, machining a middle hole of Φ400, the blanking weight is 35.249Kg, and after setting the die stroke according to the above-mentioned underpressure value, the blank is put into the mold to start forging; after die forging, machining is performed according to the forging size requirements, and finally the machined forging is subjected to solid solution 510℃×2h and 160℃×24h aging treatment to obtain a finished workpiece.

[0055] Comparative Example 1 like Figure 6As shown in a, a forging die for a metal forging comprises a metal forging 3, a die 1 and a punch 2. The metal forging 3 is in the shape of a hollow cone, comprising a flange 303 and a conical surface 302 located on the flange 303, and a through hole 301 is provided on the conical surface 302; the die 1 serves as the lower die, and the punch 2 serves as the upper die. When the die is working, the blank is first placed on the die 1, and the punch 2 moves downward. The middle surface of the punch 2 first contacts the blank, and then the conical surface 302 is forged. The die structure diagram is imported into the SIMUFACT FORMING software, and the same parameters are set as above to obtain the simulation results as shown in the figure. Figure 6 As shown in b, the flange 303 of the metal forging 3 cannot be formed in place, and during the operation of this type of mold, due to the large contact area between the punch 2 and the metal forging 3, the metal forging 3 is easy to adhere to the punch 2 after forming and move upward with the punch 2, making it difficult to remove the material.

[0056] Comparative Example 2 like Figure 7 As shown in Figure 1, a forging die for a metal forging includes a metal forging 3, a die 1 and a punch 2. The metal forging 3 is in the shape of a hollow cone, including a flange 303 and a conical surface 302 located on the flange 303. The conical surface 302 is provided with a through hole 301. The die 1 is used as an upper die, and the punch 2 is used as a lower die. The die structure diagram is imported into the SIMUFACTFORMING software, and the same parameters are set as above. The simulation results are as shown in Figure 1. Figure 7 As shown in b, the flange 303 of the metal forging 3 cannot be formed into place.

[0057] When faced with the problem of the flange 303 not being formed properly in the comparative example, technicians usually increase the thickness of the blank and add metal materials to force more metal materials to flow into the flange 303, so that the flange 303 is fully filled and formed properly. However, this method will increase the underpressure value of the metal forging 3, increase the thickness of the forging surface, require a large forming force, and seriously waste materials.

[0058] A person skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0059] One or more embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the present application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of the present application should be included in the protection scope of the present application.

Claims

1. A forging die for a metal forging, wherein the metal forging (3) is in the shape of a hollow cone, comprising a flange (303) and a conical surface (302) located on the flange (303), wherein a through hole (301) is provided on the conical surface (302); the forging die comprises a concave die (1) and a convex die (2) arranged opposite to each other, wherein: The die (1) and / or the punch (2) are provided with a forging protrusion (4); the height of the forging protrusion (4) is 13-17 millimeters, and the aperture of the through hole (301) is smaller than the diameter of the forging protrusion (4).

2. A forging die for a metal forging as claimed in claim 1, characterized in that: The outer edges of the concave die (1) and the convex die (2) are planes, and after forging, a space for accommodating the flange (303) is formed within the two planes.

3. A forging die for a metal forging as claimed in claim 2, characterized in that: The outer periphery of the plane of the male mold (2) is provided with a guide outer wall (201), and the outer periphery of the plane of the female mold (1) is provided with a corresponding guide inner wall (101).

4. A forging die for a metal forging as claimed in claim 1, characterized in that The die (1) is provided with a forging protrusion (4), and the height of the forging protrusion (4) is 15 millimeters.

5. A forging die for a metal forging as claimed in claim 4, characterized in that: The male mold (2) is provided with a positioning protrusion (5), and the positioning protrusion (5) can be accommodated in the through hole (301).

6. A forging die for a metal forging according to any one of claims 1 to 5, characterized in that: The outer periphery of the forging protrusion (4) is provided with a receiving groove (103), the receiving groove (103) being provided between the forging protrusion (4) and a forming inclined surface (102) of a die for forming a metal forging (3), the receiving groove (103) comprising a first forming surface (1031), a second forming surface (1032) and a forming inclined surface (102) connected in sequence, the first forming surface (1031) and the forging protrusion (4) being connected.

7. A forging die for a metal forging as claimed in claim 6, characterized in that: The width of the second profile (1032) is 18-22 millimeters, and the angle between the first profile (1031) and the second profile (1032) is 120°-130°.

8. A die design method for a forging die of a metal forging as claimed in claim 7, characterized in that: The steps include: S1: blank selection: select a blank to perform a hot compression test, obtain performance parameters of the blank, and input the performance parameters of the blank into a computer simulation software; S2: Preliminary drawing design of the mold: according to the workpiece drawing, the punch (2) and the die (1) are designed using computer three-dimensional drawing software, and a forging protrusion (4) is designed in the middle of the punch (2) and / or the die (1); S3: die forming simulation: the die designed in S2 is imported into the computer simulation software, the die forging parameters are set, the performance parameters of the blank and the calculation formula for the forging deformation are input, and the computer performs die forming simulation to obtain the forging parameters, which are the average deformation of the forging, the underpressure value and the thickness of the forging surface; S4: adjusting the die and the blank: comparing the forging parameters obtained in S3 with the ideal values, and adjusting the die parameters and the blank parameters according to the parameter comparison results, wherein the die parameters include the shape of the forging protrusion (4), the width of the second profile (1032), and the angle between the first profile (1031) and the second profile (1032); S5: Repeat S3 and S4 until the forging parameters reach the ideal values ​​and the optimal die parameters are obtained.

9. The die design method for a forging die of a metal forging according to claim 8, characterized in that: In S3, the calculation formula for forging deformation is: , is the equivalent plastic strain.

10. The die design method for a forging die of a metal forging according to claim 8, characterized in that: In S3, the die forging parameters set are die and billet temperature, die and billet friction coefficient, upper die downward distance, and die maximum stop pressure.

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