Forging forming method and die for large hinge beam die forging for airplane

Abstract

The invention discloses a forging forming method and die for a large hinge beam die forging for an airplane, and relates to the technical field of forging. According to the specific technical scheme, the method comprises the steps of heating before forging, cast ingot forging changing, machining, blank making heating, forging blank making, saw cutting, polishing damage repairing, first heating number heating of die forging, first heating number forging of die forging, first trimming, first corrosive washing damage repairing, second heating number heating of die forging, second heating number forging of die forging, second trimming, second corrosive washing damage repairing and size detection. According to the forging forming method for the 7050 aluminum alloy large hinge beam forge piece for the airplane, the forge piece which is qualified in size and uniform in structure property is obtained, and the use requirement is met.

Description

Technical Field

[0001] The invention belongs to the technical field of alloy forging, and in particular relates to a forging method and a die for a large hinge beam die forging for an aircraft. Background Art

[0002] There is a typical forging on large aircraft, which is the largest die forging among the high-strength and high-toughness 7050 aluminum alloy aviation mounting beam precision die forgings: hinge beam die forging. The hinge beam die forging is a precision die forging and a beam structure die forging. The maximum size of the part is 453.3×441.4×2860mm, and the maximum outer contour size of the die forging is 496×700×3237mm.

[0003] Hinge beam forgings such as Figure 1 and Figure 2 As shown, Figure 1 A first side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention; Figure 2 It is a second side view structural schematic diagram of the 7050 aluminum alloy hinge beam die forging provided by the embodiment of the present invention. It is a relatively complex large aluminum alloy forging. The maximum outer length of the forging exceeds 3000mm, the maximum thickness is 496mm, and the minimum thickness is 146mm. The forging has an overall asymmetrical structure on the left and right sides, with a maximum drop of more than 300mm, and the volume distribution in the length direction is uneven, mainly concentrated at one end. Its basic body mainly includes multiple steps of the support part 101, the inner side of the support part is supported by three main side ribs 102, and its main body support part 101 extends forward to form a front beam part 104, and the connection is composed of three planes of different heights. The other side of the support part 101 is composed of a connecting boss 105, and there are 11 processing bosses 103 evenly distributed around the whole. The overall structural shape of the forging is complex, the slope is large, there is no directionality and symmetry correspondence, and the molding difficulty is high. It belongs to the type of forging that is difficult to mold and prone to defects.

[0004] The hinge beam die forging itself is a relatively precise die forging, which is a frame beam type die forging with a deep cavity, high ribs, large cross-section changes, small rounded corners, many bosses, and a relatively complex structure. The shape of the hinge beam die forging is basically close to the parts, with small machining allowance, high surface quality requirements, and high dimensional accuracy requirements; the die forging has a deep cavity, high ribs and a large bevel angle, which makes it difficult to die forge; the 7050 alloy is prone to coarse grains, and it is difficult to control the uniformity of organizational properties, and the metal flow direction is not easy to control; the forging size specifications are large, which increases the difficulty of various aspects in disguise, and there is less experience in the molding of related products. At the same time, the product working environment requirements are high, and the comprehensive performance requirements are high. Therefore, the biggest difficulty of hinge beam die forgings is the difficulty in dimensional control and the difficulty in controlling the uniformity of organizational properties.

[0005] Therefore, how to provide a forging method for large hinge beam forgings of 7050 aluminum alloy for aircraft to improve product quality and accumulate product experience and performance data is a technical problem that urgently needs to be solved by technical personnel in this field. Summary of the invention

[0006] Based on the above background, the purpose is to provide a forging method for large hinge beam forgings of 7050 aluminum alloy for aircraft, so as to obtain forgings with qualified size and uniform microstructure and properties to meet the use requirements.

[0007] In view of this, according to one aspect of an embodiment of the present invention, a forging method for a large hinge beam die forging for an aircraft is provided, comprising:

[0008] Step S01: heating before forging: the upper and lower flat anvils and the drawing anvil of the die are heated to a fixed temperature of 350-450°C and kept warm for ≥10 hours; the 7050 aluminum alloy ingot is heated to 440±10°C and kept warm for 770-1070 minutes to form a blank;

[0009] Step S02: Ingot reforging: using upper and lower flat anvils and a drawing anvil, the billet is taken out of the furnace for forging after reaching the minimum holding time, and after three fires, it is upsetting and drawing to form a reforged billet;

[0010] Step S03 machining: peel the outer surface of the forged blank, the surface roughness after outer circle machining is Ra6.3, the pinhole at the end needs to be polished to a smooth transition, and the grinding width-to-depth ratio is not less than 6:1;

[0011] Step S04: Blank heating: the drawing anvil is heated to a fixed temperature of 350-450°C and kept at this temperature for ≥10 hours; the machined reforging blank is heated to 440±10°C and kept at this temperature for 640-940 minutes;

[0012] Step S05 forging: using a drawing anvil, the heated forging blank is taken out of the furnace for forging after reaching the minimum holding time, and the forging is flattened to a preset length from the end including the sawn surface, and the remaining part is respectively drawn to three preset sizes. During the drawing process, the downward pressure is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃;

[0013] Step S06: sawing: sawing the end of the forged blank after forging, the sawing length is controlled at a preset value, the edge chamfer of the rear end face is R5-R10, the sawing surface roughness is Ra3.2, and a forging is formed;

[0014] Step S07: Grinding and repairing: Grinding the surface defects of the forgings and making them smooth, and chamfering the edges by R5 to R10;

[0015] Step S08: First heating of die forging: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used to raise the upper and lower dies; the forging after grinding and repair is heated to 440±10°C and kept warm for 640-940 minutes;

[0016] Step S09: First die forging: forging after loading the die, setting the zero position after the upper and lower dies are closed, performing die lifting and lubrication once during the pressing process, and air cooling or wind cooling to room temperature after forging;

[0017] Step S10: first trimming: trimming the forgings produced by the first forging;

[0018] Step S11: First etching and repairing: etching and cleaning the forging after the first trimming, grinding and removing the surface defects and making a smooth transition, chamfering the edges R5 to R10, and etching and cleaning again after grinding, and checking the surface again until the defects are completely removed;

[0019] Step S12: Die forging second heating: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used to raise the upper and lower dies; the forging after the first etching and repair is heated to 440±10°C and kept warm for 400-580 minutes;

[0020] Step S13: forging the second die forging: after loading the die, forging is performed, the upper and lower dies are closed and set to zero position, and air-cooled or wind-cooled to room temperature after forging;

[0021] Step S14: second trimming: trimming the forging after the second forging;

[0022] Step S15: Second etching and repairing: chemically etching the forging after the second trimming, grinding and removing the surface defects and making a smooth transition, chamfering the edges R5 to R10, and etching again after grinding, and checking the surface again until the defects are completely removed;

[0023] Step S16: Dimension inspection: Dimension inspection is performed on the forging after the second etching and cleaning repair, and a large hinge beam die forging for aircraft is formed after passing the inspection.

[0024] Optionally, step S02 also includes: first upsetting and drawing, heating temperature 440±10℃, heat preservation 340~640min, upsetting pressing speed setting value 5~10mm / s during deformation process, pressing amount ≤70mm during drawing process, feed amount ≤300mm, transfer time ≤150s, start forging temperature ≥410℃, final forging temperature ≥350℃, and mold temperature ≥250℃.

[0025] Optionally, step S02 also includes: a second upsetting and drawing process, a heating temperature of 440±10°C, a heat preservation of 290 to 590 minutes, an upsetting pressing speed setting value of 5 to 10 mm / s during the deformation process, a pressing amount during the drawing process of ≤70 mm and a feeding amount of ≤300 mm, a transfer time of ≤150 seconds, a start forging temperature of ≥410°C, a final forging temperature of ≥350°C, and a mold temperature of ≥250°C.

[0026] Optionally, step S02 also includes: a third time of drawing and rounding to obtain a modified forging blank, air cooling to room temperature after forging, the downward pressure during the drawing process is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410°C, the final forging temperature is ≥350°C, and the mold temperature is ≥250°C.

[0027] Optionally, after step S03, the method further includes:

[0028] According to the requirements of ASTM B594, the outer cylindrical surface of the machined forged blank is tested by contact method piece by piece, and the testing level is A.

[0029] Optionally, after step S03, the method further includes:

[0030] Step S031 Sampling: sawing is performed at any end of the processed forged blank, and the length of the sawing sample is ≥80mm. The samples include longitudinal tensile samples, high-magnification test blocks, fracture samples, and low-magnification test pieces. The sawing end face edge chamfers are R5-R10, and the sawing surface roughness is Ra3.2;

[0031] Step S032: heat treatment of the sample: performing solution treatment and aging treatment on the sample;

[0032] Step S033: Sample testing: Mechanical properties testing is performed on longitudinal tensile specimens, and acceptance is based on the performance indicators of AMS4108, where the heat treatment thickness is ≤51mm;

[0033] The low-power tissue examination is carried out on a low-power test machine and is carried out in accordance with the requirements of GJB2351;

[0034] High-magnification microstructure inspection is carried out on a high-magnification test machine in accordance with the requirements of GJB2351;

[0035] The fracture microstructure inspection is carried out on the fracture test block according to the requirements of GJB2351.

[0036] Optionally, the method for solution treating the sample in step S032 also includes: using a heat treatment furnace, loading the sample after the furnace temperature is stabilized at 476±5°C, and the sample loading distance is more than 50mm; the heating system is set at 476±5°C, and the heat preservation is 60-70min, the heating medium is air, and after the heat preservation is completed, the sample is taken out of the furnace and water-cooled, the water temperature is 33-36°C, and the transfer time is 15s.

[0037] Optionally, the method for aging the sample in step S032 also includes: using a heat treatment furnace, loading the sample after the furnace temperature stabilizes at 121±5°C, and the sample loading distance is more than 50mm; the first stage of the heating system is set at a constant temperature of 121±5°C, and the temperature is kept for 360 to 370 minutes; the second stage is set at a constant temperature of 177±5°C, and the temperature is kept for 540 to 550 minutes, the heating medium is air, and the sample is cooled by air after the temperature is kept.

[0038] According to another aspect of an embodiment of the present invention, a forging die for large hinge beam die forgings for aircraft is provided, comprising a forging modification die 3, a blanking die 4 and a forging die 5, wherein the forging modification die 3 further comprises a forging modification upper die 301 and a forging modification lower die 302, the blanking die 4 is used to round and shape the blank to a blank 303, the blanking die 4 further comprises a blanking upper die 401 and a blanking lower die 402, the forging die 5 comprises a forging upper die 501, a forging lower die 502, a forging guide post 503 and a forging ejector 504, during die forging 1, the blank 505 is placed on the die forging lower die 502, the plane of the first platform 506 of the lower die is in contact with the plane of the large end of the blank 505 and stabilized, the die forging upper die 501 is pressed down to contact the blank, and the blank metal first fills the plane 506, When continuing to flow, it is restricted by the surrounding cavity and the burr groove 516 of the outermost circle of the die forging lower die 502, forcing the blank metal to flow as a whole toward the second platform 507, the third platform 508, the fourth platform 509, the fifth platform 510, the sixth platform 511 and the seventh platform 512 of the lower die through the lower die 502, where the depths of the lower die increase successively; the pre-forged blank is placed in the die forging lower die 502, and the metal continues to flow under the downward pressure of the die forging upper die 501, filling each part of the cavity piece by piece to complete the final forging; the die forging ejector 504 is used to eject the forging, and the die forging guide pin 503 is used to position the die forging upper die 501 and the die forging lower die 502.

[0039] The forming process of the 7050 aluminum alloy hinge beam forging provided by the present invention has been tested by multiple pieces and multiple batches of anatomical physical and chemical tests. The overall deformation of the forging is uniform, the microstructure is not overburned, the grains are uniform, and the streamlines are distributed along the shape of the forging. All the tests of the prepared forgings meet the requirements of AMS4108 and GJB2351, including: room temperature tensile, hardness: HB153 to HB155, conductivity: 39.54% IACS to 40.31% IACS, low magnification: grain size level 1, high magnification: not overburned, stress corrosion: qualified, fracture toughness: KIC = 33.1MPa·m 1 / 2, fracture: no non-metallic inclusions, no oxide film. The forming process parameters are relatively reasonable, each forging is well formed, the batch production stability is excellent, and the process has the finalization conditions, indicating that the hinge beam die forging forming process has achieved the expected goal and meets the use requirements of commercial aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 1 is a first side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention;

[0041] Figure 2 1 is a second side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention;

[0042] Figure 3 It is a structural schematic diagram of the modified forging die of the present invention;

[0043] Figure 4 It is a structural schematic diagram of the blank making mold of the present invention;

[0044] Figures 5-1 to 5-4 It is a structural schematic diagram of the die forging die of the present invention.

[0045] Description of reference numerals:

[0046] 1-7050 aluminum alloy hinge beam die forging, 101-support part 101, 102-side ribs, 103-processing boss, 104-front beam part, 105-connecting boss, 301-forging die upper die, 302-forging die lower die, 303-forging blank, 401-blank making die upper die, 402-blank making die lower die, 403-blank making blank, 501-die forging die upper die, 502-die forging die lower die, 503 -die forging die guide pin, 504-die forging die ejector, 505-die forging blank, 506-lower die first platform, 507-lower die second platform, 508-lower die third platform, 509-lower die fourth platform, 510-lower die fifth platform, 511-lower die sixth platform, 512-lower die seventh platform, 513-lower die first slope, 514-lower die second slope, 515-lower die third slope, 516-burr groove. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] According to one aspect of an embodiment of the present invention, a forging method for a large hinge beam die forging for an aircraft is provided, comprising:

[0049] Step S01: Heating before forging: The upper and lower flat anvils and the drawing anvil of the die are heated to a fixed temperature of 350-450°C and kept at this temperature for ≥10 hours. The 7050 aluminum alloy ingot is heated to 440±10°C and kept at this temperature for 770-1070 minutes to form a blank. Before step S01, sawing and blanking may also be included: Ingot specification: 7050 aluminum alloy, the diameter after processing and removing the segregation layer is Sawing length 1345~1355mm.

[0050] Step S02: Ingot reforging: using upper and lower flat anvils and a drawing anvil, the billet is taken out of the furnace for forging after reaching the minimum holding time, and after three fires, it is upsetting and drawing to form a reforged billet;

[0051] Step S03 machining: peel the outer surface of the forged blank, the surface roughness after outer circle machining is Ra6.3, the pinhole at the end needs to be polished to a smooth transition, and the grinding width-to-depth ratio is not less than 6:1;

[0052] Step S04: Blank heating: the drawing anvil is heated to a fixed temperature of 350-450°C and kept at this temperature for ≥10 hours; the machined reforging blank is heated to 440±10°C and kept at this temperature for 640-940 minutes;

[0053] Step S05 forging: using a drawing anvil, the heated forging blank is taken out of the furnace for forging after reaching the minimum holding time, and the forging is flattened to a preset length from the end including the sawn surface, and the remaining part is respectively drawn to three preset sizes. During the drawing process, the downward pressure is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃;

[0054] Step S06: sawing: sawing the end of the forged blank after forging, the sawing length is controlled at a preset value, the edge chamfer of the rear end face is R5-R10, the sawing surface roughness is Ra3.2, and a forging is formed;

[0055] Step S07: Grinding and repairing: Grinding the surface defects of the forgings and making them smooth, and chamfering the edges by R5 to R10;

[0056] Step S08: First heating of die forging: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used to raise the upper and lower dies; the forging after grinding and repair is heated to 440±10°C and kept warm for 640-940 minutes;

[0057] Step S09: First die forging: forging after loading the die, setting the zero position after the upper and lower dies are closed, performing die lifting and lubrication once during the pressing process, and air cooling or wind cooling to room temperature after forging;

[0058] Step S10: first trimming: trimming the forgings produced by the first forging;

[0059] Step S11: First etching and repairing: etching and cleaning the forging after the first trimming, grinding and removing the surface defects and making a smooth transition, chamfering the edges R5 to R10, and etching and cleaning again after grinding, and checking the surface again until the defects are completely removed;

[0060] Step S12: Die forging second heating: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used to raise the upper and lower dies; the forging after the first etching and repair is heated to 440±10°C and kept warm for 400-580 minutes;

[0061] Step S13: forging the second die forging: after loading the die, forging is performed, the upper and lower dies are closed and set to zero position, and air-cooled or wind-cooled to room temperature after forging;

[0062] Step S14: second trimming: trimming the forging after the second forging;

[0063] Step S15: Second etching and repairing: chemically etching the forging after the second trimming, grinding and removing the surface defects and making a smooth transition, chamfering the edges R5 to R10, and etching again after grinding, and checking the surface again until the defects are completely removed;

[0064] Step S16: Dimension inspection: Dimension inspection is performed on the forging after the second etching and cleaning repair, and a large hinge beam die forging for aircraft is formed after passing the inspection.

[0065] Furthermore, step S02 also includes: the first upsetting and drawing, the heating temperature is 440±10℃, the heat preservation is 340~640min, the upsetting pressing speed setting value of the deformation process is 5~10mm / s, the pressing amount during the drawing process is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃.

[0066] Furthermore, step S02 also includes: second upsetting and drawing, heating temperature 440±10℃, heat preservation 290~590min, upsetting pressing speed setting value 5~10mm / s during deformation process, pressing amount ≤70mm and feeding amount ≤300mm during drawing process, transfer time ≤150s, start forging temperature ≥410℃, final forging temperature ≥350℃, and mold temperature ≥250℃.

[0067] Furthermore, step S02 also includes: a third time of drawing and rounding to obtain a modified forging blank, air cooling to room temperature after forging, the downward pressure during the drawing process is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410°C, the final forging temperature is ≥350°C, and the mold temperature is ≥250°C.

[0068] Furthermore, after step S03, the method further includes:

[0069] According to the requirements of ASTM B594, the outer cylindrical surface of the machined forged blank is tested by contact method piece by piece, and the testing level is A.

[0070] Furthermore, after step S03, the method further includes:

[0071] Step S031 Sampling: sawing is performed at any end of the processed forged blank, and the length of the sawing sample is ≥80mm. The samples include longitudinal tensile samples, high-magnification test blocks, fracture samples, and low-magnification test pieces. The sawing end face edge chamfers are R5-R10, and the sawing surface roughness is Ra3.2;

[0072] Step S032: heat treatment of the sample: performing solution treatment and aging treatment on the sample;

[0073] Step S033: Sample testing: Mechanical properties testing is performed on longitudinal tensile specimens, and acceptance is based on the performance indicators of AMS4108, where the heat treatment thickness is ≤51mm;

[0074] The low-power tissue examination is carried out on a low-power test machine and is carried out in accordance with the requirements of GJB2351;

[0075] High-magnification microstructure inspection is carried out on a high-magnification test machine in accordance with the requirements of GJB2351;

[0076] The fracture microstructure inspection is carried out on the fracture test block according to the requirements of GJB2351.

[0077] Furthermore, the method of performing solution treatment on the sample in step S032 also includes: using a heat treatment furnace, loading the sample after the furnace temperature is stabilized at 476±5°C, and the sample loading distance is more than 50mm; the heating system is set at 476±5°C, and the heat preservation is 60-70min, the heating medium is air, and after the heat preservation is completed, the sample is taken out of the furnace and water-cooled, the water temperature is 33-36°C, and the transfer time is 15s.

[0078] Furthermore, the method for aging the sample in step S032 also includes: using a heat treatment furnace, loading the sample after the furnace temperature stabilizes at 121±5°C, and the sample loading distance is more than 50mm; the first stage of the heating system is set at a temperature of 121±5°C, and the temperature is kept for 360 to 370 minutes; the second stage is set at a temperature of 177±5°C, and the temperature is kept for 540 to 550 minutes. The heating medium is air, and the sample is cooled by air after the temperature is kept.

[0079] According to another aspect of an embodiment of the present invention, a forging die for large hinge beam die forgings for aircraft is provided, comprising a forging modification die 3, a blanking die 4 and a forging die 5, wherein the forging modification die 3 further comprises a forging modification upper die 301 and a forging modification lower die 302, the blanking die 4 is used to round and shape the blank to a blank 303, the blanking die 4 further comprises a blanking upper die 401 and a blanking lower die 402, the forging die 5 comprises a forging upper die 501, a forging lower die 502, a forging guide post 503 and a forging ejector 504, during die forging 1, the blank 505 is placed on the die forging lower die 502, the plane of the first platform 506 of the lower die is in contact with the plane of the large end of the blank 505 and stabilized, the die forging upper die 501 is pressed down to contact the blank, and the blank metal first fills the plane 506, When continuing to flow, it is restricted by the surrounding cavity and the burr groove 516 of the outermost circle of the die forging lower die 502, forcing the blank metal to flow as a whole toward the second platform 507, the third platform 508, the fourth platform 509, the fifth platform 510, the sixth platform 511 and the seventh platform 512 of the lower die through the lower die 502, where the depths of the lower die increase successively; the pre-forged blank is placed in the die forging lower die 502, and the metal continues to flow under the downward pressure of the die forging upper die 501, filling each part of the cavity piece by piece to complete the final forging; the die forging ejector 504 is used to eject the forging, and the die forging guide pin 503 is used to position the die forging upper die 501 and the die forging lower die 502.

[0080] Example 1

[0081] refer to Figure 1-Figure 4 , Figure 1 A first side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention; Figure 2 1 is a second side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention; Figure 3 It is a structural schematic diagram of the forging die of the present invention; Figure 4 It is a structural schematic diagram of the blank making mold of the present invention; Figure 5-1 to Figure 5-4 : is a structural schematic diagram of the die forging die of the present invention; a forming process of a 7050 aluminum alloy hinge beam die forging 1 provided in an embodiment of the present invention comprises:

[0082] Step 1) Cutting: Ingot specification: 7050 aluminum alloy, after processing and removing the segregation layer, the diameter is Sawing length 1345~1355mm;

[0083] Step 2) Heating before forging: The upper and lower flat anvils of the die and the 500 mm drawing anvil are heated to a fixed temperature of 350-450°C and kept warm for ≥10 hours; the ingot is heated to 440±10°C and kept warm for 770-1070 minutes;

[0084] Step 3-1) Ingot forging for 1 fire: Use a 2500-ton hydraulic press with upper and lower flat anvils. After the billet reaches the minimum holding time, it is taken out of the furnace for forging. The heated 7050 ingot is taken out for upsetting. It is upsetting from a height of 1345mm to 680mm, and then it is pulled to a square of 560mm×1100mm. 1100 continues upsetting to 560mm. After it continues to be pulled to a square of 560mm×1100mm, the hot material is returned to the furnace for heating. The billet heating temperature is 440±10℃, and it is kept warm for 340~640min. 1 fire is completed. The setting value of the upsetting pressing speed during the deformation process is 5~10mm / s, the pressing amount during the pulling process is ≤70mm, the billet feed amount is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃;

[0085] Step 3-2) Ingot forging 2-fire: Use a 2500-ton hydraulic press with upper and lower flat anvils. After the billet reaches the minimum holding time, it is taken out of the furnace for forging. The billet is upset from 1100mm to 560mm, shaped to 560mm×780mm×780mm, and then stretched to a square □480mm×1500mm. After that, the hot material is returned to the furnace for heating. The billet heating temperature is 440±10℃, and the insulation is 290~590min. The 2-fire is completed. The setting value of the upsetting pressing speed during the deformation process is 5~10mm / s, the pressing amount during the stretching process is ≤70mm, the billet feed amount is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃;

[0086] Step 3-3) Ingot forging 3 times: Use a 2500 ton hydraulic press with a 500 mm long anvil. After the billet reaches the minimum holding time, it is taken out of the furnace for forging. The billet is taken out and turned from square □480mm to square □485mm. Finally, it is rolled and stretched to obtain the forged billet. After forging, air cool to room temperature. During the drawing process, the downward pressure is ≤70mm, the billet feed is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the die temperature is ≥250℃;

[0087] Step 4) Machining: Use a lathe to peel the outer surface of the forged billet. The surface roughness after outer circle machining is Ra6.3, the pinhole at the end needs to be polished to a smooth transition, and the grinding width-to-depth ratio is not less than 6:1;

[0088] Step 5) Ultrasonic flaw detection: According to the requirements of ASTM B594, the outer cylindrical surface of the forging is tested by contact method piece by piece, and the flaw detection level is Class A.

[0089] Step 6) Sampling: Saw at any end of the forging, the length of the sawing sample is ≥80mm, and the sampling content includes: 2 longitudinal tensile specimens (1 / 2 radius), 3 high-magnification test blocks (center, 1 / 2 radius, surface), 1 fracture specimen, and 1 low-magnification test piece. The length of the forging after sawing is ≥1630mm, the sawing end face edge chamfer is R5~R10, and the sawing surface roughness is Ra3.2;

[0090] Step 7) Heat treatment of samples: Solution treatment: Use 96# aluminum alloy heat treatment furnace, and load the furnace after the furnace temperature stabilizes at 476±5℃, with a sample loading distance of more than 50mm; The heating system is set at 476±5℃, and the temperature is kept for 60-70min. The heating medium is air. After the insulation is completed, the furnace is taken out and water-cooled. The water temperature is 33-36℃, and the transfer time is 15s; Aging treatment: Use 96# aluminum alloy heat treatment furnace, and load the furnace after the furnace temperature stabilizes at 121±5℃, with a sample loading distance of more than 50mm; The first stage of the heating system is set at 121±5℃, and the temperature is kept for 360-370min; The second stage is set at 177±5℃, and the temperature is kept for 540-550min. The heating medium is air. After the insulation is completed, the furnace is taken out and air-cooled;

[0091] Step 8) Sample testing: Mechanical properties (tensile) test is carried out on longitudinal tensile specimens: acceptance according to AMS4108, where the heat treatment thickness is ≤51mm;

[0092] Low-power tissue examination is carried out on a low-power test machine: inspection is carried out in accordance with the requirements of GJB2351;

[0093] High-magnification tissue inspection is carried out on a high-magnification test machine: inspection is carried out in accordance with the requirements of GJB2351;

[0094] The fracture microstructure inspection is carried out on the fracture test block: the inspection is carried out according to the requirements of GJB2351;

[0095] Step 9) Blank heating: 500 mm long anvil is heated to a fixed temperature of 350-450°C, and kept warm for ≥10 hours; the blank is heated to 440±10°C, and kept warm for 640-940 minutes;

[0096] Step 10) Forging: Use a 2500 ton hydraulic press with a 500 mm drawing anvil. After the billet reaches the minimum holding time, take it out of the furnace for forging. Take out the heated billet and forge it from the end containing the sawn surface to 420 ± 10 mm, with a length of 375 to 400 mm. The remaining parts are drawn to

[0097] During the drawing process, the downward pressure is ≤70mm, the billet feeding amount is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the die temperature is ≥250℃;

[0098] Step 11) Sawing: Cutting the blank End, the length of the blank after sawing is controlled at 2920~2950mm, the edge chamfer of the rear end face after sawing is R5~R10, and the roughness of the sawn surface is Ra3.2.

[0099] Step 12) Grinding and repairing: Grind away any possible cracks, folds, sharp corners, and other defects on the forging surface and make them smooth, with edge chamfers of R5 to R10;

[0100] Step 13) Die forging 1 fire heating: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used between the upper and lower dies to raise the height by 50-100mm; the blank is heated to 440±10°C and kept warm for 640-940min;

[0101] Step 14) Die forging 1: Use a 50,000-ton hydraulic press to load the die for forging. Set the zero position after the upper and lower dies are closed. Press down from a height of 370 mm to 70 mm at a speed of 5 mm / s. Lift the upper die to lubricate the die cavity surface and the blank. Press down from a closing height of 80 mm at a speed of 3 mm / s to a height of 20 ± 5 mm. The thickness of the extended section is measured to be 191 ± 5 mm. Air cool or wind cool to room temperature after forging.

[0102] Step 15) Trimming: Trim according to the trimming wire frame dedicated to forgings. The burr residue after trimming is 15 to 40 mm, and the local position is allowed to be greater than 40 mm;

[0103] Step 16) Etching and repairing: Forgings are chemically etched to remove surface oil and other attachments. Any defects such as cracks, folds, sharp corners, etc. that may exist on the surface are polished and removed and rounded, with edge chamfers of R5 to R10. After polishing, they need to be etched again and the surface checked again until the defects are completely removed;

[0104] Step 17) Die forging 2-fire heating: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used between the upper and lower dies to raise the height by 50-100mm; the blank is heated to 440±10°C and kept warm for 400-580min;

[0105] Step 18) Die forging 2: Use a 50,000-ton hydraulic press to load the die for forging. Set the zero position after the upper and lower dies are closed. Press down from a height of 40 mm at a speed of 2 mm / s to a height of 6±4 mm. The thickness of the extended section is measured to be 171±5 mm. After forging, air cool or wind cool to room temperature.

[0106] Step 19) Trimming: Trim the edges according to the trimming wire frame specially used for forgings, and the residual burr after trimming is 5 to 35 mm;

[0107] Step 19) Etching and repairing: Forgings are chemically etched to remove surface oil and other attachments. Any defects such as cracks, folds, sharp corners, etc. that may exist on the surface are polished and removed and rounded, with edge chamfers of R5 to R10. After polishing, they need to be etched again and the surface checked again until the defects are completely removed;

[0108] Step 20) Dimension inspection: Perform three-dimensional scanning on each forging piece and compare it with the digital model of the forging piece to check whether there is any incomplete cavity or deformation.

[0109] Through multiple pieces and multiple batches of anatomical physical and chemical tests, the overall deformation of the forging is uniform, the microstructure is not over-burned, the grains are uniform, and the streamlines are distributed along the shape of the forging. The 7050 aluminum alloy large hinge beam forgings prepared by the present invention meet the requirements of AMS4108 and GJB2351 in all tests, including: room temperature tensile, hardness: HB153 to HB155, conductivity: 39.54% IACS to 40.31% IACS, low magnification: grain size level 1, high magnification: not over-burned, stress corrosion: qualified, fracture toughness: K IC =33.1MPa·m 1 / 2 , fracture: no non-metallic inclusions, no oxide film. The forming process parameters are relatively reasonable, and each forging is well formed, indicating that the development of the hinge beam die forging process has achieved the expected goal and meets the use requirements of commercial aircraft.

[0110] Specifically, in step 2), the upper and lower flat anvils of the die are heated to a fixed temperature of 400°C, heated and kept warm for more than 10 hours, and the billet is kept warm for 960 minutes; in step 3-1), the start forging temperature is 415°C, the final forging temperature is 387°C, the forging plan is upsetting to 670-690mm, and then stretched to a square Continue to upsetting to 550-570mm, then stretch to square This process completes the upsetting deformation in two directions of the original ingot direction; in step 3-2), the billet is kept warm for 828 minutes, the start forging temperature is 417°C, the final forging temperature is 387°C, the forging plan is upset to 550-570mm, and then drawn to the square Continue to lengthen and reshape to the four sides This process completes the upsetting deformation in the last direction of the original ingot direction; in step 3-3), the billet is kept warm for 300 minutes, the upper and lower flat anvils are changed to 500mm long anvils, the start forging temperature is 417℃, the final forging temperature is 382℃, and the forging plan is chamfered and drawn to eight sides. Continue rolling until In step 9), the die 500mm drawing anvil is set at 400℃, heated and kept warm for more than 10 hours, and the billet is kept warm for 770min; in step 10), the start forging temperature is 417℃, the final forging temperature is 372℃, and the forging plan is used to upset the sawing end to 410-430mm, and then continue to draw four steps respectively. In step 13), the die forging die is set at a constant temperature of 400°C, heated and kept warm for more than 10 hours, and the billet is kept warm for 669 minutes; in step 14), a 50,000-ton die forging hydraulic press is equipped with a special die forging die, the start forging temperature is 416°C, the final forging temperature is 406°C, and the two pressing processes are set to a pressing speed of 5mm / s and 3mm / s respectively, the underpressure is 23-25mm, and the pressure is 43,000 tons; in step 14), a 50,000-ton die forging hydraulic press is equipped with a special die forging die, the billet is kept warm for 477 minutes, the start forging temperature is 415°C, the final forging temperature is 406°C, the pressing speed is set to 2mm / s, the underpressure is 6-8mm, and the pressure is 50,000 tons.

[0111] Example 2

[0112] For ease of understanding, the present invention also provides a set of dies used in conjunction with the above-mentioned 7050 aluminum alloy hinge beam die forging 1 forming method, including a reforming forging die 3, a blanking die 4, and a die forging die 5. Figure 1-Figure 4 , Figure 1 A first side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention; Figure 2 1 is a second side structural schematic diagram of a 7050 aluminum alloy hinge beam die forging provided in an embodiment of the present invention; Figure 3 It is a structural schematic diagram of the forging die of the present invention; Figure 4 It is a structural schematic diagram of the blank making mold of the present invention; Figure 5-1 to Figure 5-4 It is a structural schematic diagram of the die forging die of the present invention; when in use:

[0113] First, the cylindrical ingot is upset and stretched in three directions by using a forging die 3, which includes an upper forging die 301 and a lower forging die 302. The blank is rounded and shaped into a blank 303 by using a billet making die 4, which includes an upper billet making die 401 and a lower billet making die 402.

[0114] Then, the blank is flattened at one end by using a blank-making mold 4 , and then stretched in multiple steps to a blank 403 . The blank-making mold 4 includes a blank-making upper mold 401 and a blank-making lower mold 402 .

[0115] Afterwards, a die forging die 5 is used to perform die forging 1 to form a pre-forged part. The die forging die 5 includes a die forging upper die 501, a die forging lower die 502, a die forging guide post 503, and a die forging ejector 504.

[0116] During the die forging, the blank 505 is placed on the die forging lower die 502, and the 506 plane is in contact with the plane of the big end of the blank 505 to stabilize it. The die forging upper die 501 is pressed down to contact the blank. The metal first fills the 506 plane. When it continues to flow, it is restricted by the surrounding cavity and the burr groove 516, forcing the metal to flow through the slopes 513, 514, and 515 as a whole to the grooves 507, 508, 509, 510, 511, and 512. Because the groove 512 has the largest depth and requires the most metal filling, the metal overflowing from the front groove will eventually flow to 512. However, in order to control the die forging to not cause excessive deformation, a fixed pressing amount is set, and the thickness of the groove 507 is used as the control dimension. The cavity will not be filled at all places.

[0117] Finally, the die forging die 5 is continued to be used for die forging 2, and the pre-forged blank is placed in the die forging lower die 502. Under the downward pressure of the die forging upper die 501, the metal continues to flow and fills the cavity piece by piece to complete the final forging 1, and then the forging is ejected out of the die by the ejector 504.

[0118] Example 3

[0119] A forging method for a large hinge beam die forging for an aircraft comprises the following steps:

[0120] Sawing and cutting → Heating before forging → Ingot forging 1, 2, 3 fires → Machining → Ultrasonic flaw detection → Sampling → Sample heat treatment → Sample testing → Billet heating → Forging billet → Sawing → Grinding and repairing → Die forging 1 fire heating → Die forging 1 fire → Trimming → Cleaning and repairing → Die forging 2 fire heating → Die forging 2 fire → Trimming → Cleaning and repairing → Dimension testing

[0121] Step 1) Cutting: Ingot specification: 7050 aluminum alloy, after processing and removing the segregation layer, the diameter is Sawing length 1345~1355mm;

[0122] Step 2) Heating before forging: The upper and lower flat anvils of the die and the 500 mm drawing anvil are heated to a fixed temperature of 350-450°C and kept warm for ≥10 hours; the ingot is heated to 440±10°C and kept warm for 770-1070 minutes;

[0123] Step 3-1) Ingot forging for 1 fire: Use a 2500-ton hydraulic press with upper and lower flat anvils. After the billet reaches the minimum holding time, it is taken out of the furnace for forging. The heated 7050 ingot is taken out for upsetting. It is upsetting from a height of 1345mm to 680mm, and then it is pulled to a square of 560mm×1100mm. 1100 continues upsetting to 560mm. After it continues to be pulled to a square of 560mm×1100mm, the hot material is returned to the furnace for heating. The billet heating temperature is 440±10℃, and it is kept warm for 340~640min. 1 fire is completed. The setting value of the upsetting pressing speed during the deformation process is 5~10mm / s, the pressing amount during the pulling process is ≤70mm, the billet feed amount is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃;

[0124] Step 3-2) Ingot forging 2-fire: Use a 2500-ton hydraulic press with upper and lower flat anvils. After the billet reaches the minimum holding time, it is taken out of the furnace for forging. The billet is upset from 1100mm to 560mm, shaped to 560mm×780mm×780mm, and then stretched to a square □480mm×1500mm. After that, the hot material is returned to the furnace for heating. The billet heating temperature is 440±10℃, and the insulation is 290~590min. The 2-fire is completed. The setting value of the upsetting pressing speed during the deformation process is 5~10mm / s, the pressing amount during the stretching process is ≤70mm, the billet feed amount is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃;

[0125] Step 3-3) Ingot forging 3 times: Use a 2500 ton hydraulic press with a 500 mm long anvil. After the billet reaches the minimum holding time, it is taken out of the furnace for forging. The billet is taken out and turned from square □480mm to square □485mm. Finally, it is rolled and stretched to obtain the forged billet. After forging, air cool to room temperature. During the drawing process, the downward pressure is ≤70mm, the billet feed is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the die temperature is ≥250℃;

[0126] Step 4) Machining: Use a lathe to peel the outer surface of the forged billet. The surface roughness after outer circle machining is Ra6.3, the pinhole at the end needs to be polished to a smooth transition, and the grinding width-to-depth ratio is not less than 6:1;

[0127] Step 5) Ultrasonic flaw detection: According to the requirements of ASTM B594, the outer cylindrical surface of the machined forged blank is subjected to contact flaw detection piece by piece, and the flaw detection level is Class A.

[0128] Step 6) Sampling: Saw at any end of the processed forged blank, the length of the sawn sample is ≥80mm, and the sampling content includes: 2 longitudinal tensile specimens (1 / 2 radius), 3 high-magnification test blocks (center, 1 / 2 radius, surface), 1 fracture specimen, and 1 low-magnification test piece. The length of the forging after sawing is ≥1630mm, the edge chamfer of the sawn end face is R5~R10, and the roughness of the sawn surface is Ra3.2;

[0129] Step 7) Heat treatment of samples: Solution treatment: Use 96# aluminum alloy heat treatment furnace, and load the furnace after the furnace temperature stabilizes at 476±5℃, with a sample loading distance of more than 50mm; The heating system is set at 476±5℃, and the temperature is kept for 60-70min. The heating medium is air. After the insulation is completed, the furnace is taken out and water-cooled. The water temperature is 33-36℃, and the transfer time is 15s; Aging treatment: Use 96# aluminum alloy heat treatment furnace, and load the furnace after the furnace temperature stabilizes at 121±5℃, with a sample loading distance of more than 50mm; The first stage of the heating system is set at 121±5℃, and the temperature is kept for 360-370min; The second stage is set at 177±5℃, and the temperature is kept for 540-550min. The heating medium is air. After the insulation is completed, the furnace is taken out and air-cooled;

[0130] Step 8) Sample testing: Mechanical properties (tensile) test is carried out on longitudinal tensile specimens: acceptance according to AMS4108, where the heat treatment thickness is ≤51mm;

[0131] Low-power tissue examination is carried out on a low-power test machine: inspection is carried out in accordance with the requirements of GJB2351;

[0132] High-magnification tissue inspection is carried out on a high-magnification test machine: inspection is carried out in accordance with the requirements of GJB2351;

[0133] The fracture microstructure inspection is carried out on the fracture test block: the inspection is carried out according to the requirements of GJB2351;

[0134] Step 9) Blank heating: 500 mm long anvil is heated to a fixed temperature of 350-450°C, and kept warm for ≥10 hours; the blank is heated to 440±10°C, and kept warm for 640-940 minutes;

[0135] Step 10) Forging: Use a 2500 ton hydraulic press with a 500 mm drawing anvil. After the billet reaches the minimum holding time, take it out of the furnace for forging. Take out the heated billet and forge it from the end containing the sawn surface to 420 ± 10 mm, with a length of 375 to 400 mm. The remaining parts are drawn to

[0136] During the drawing process, the downward pressure is ≤70mm, the billet feeding amount is ≤300mm, the billet transfer time is ≤150s, the billet start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the die temperature is ≥250℃;

[0137] Step 11) Sawing: Cutting the blank End, the length of the blank after sawing is controlled at 2920~2950mm, the edge chamfer of the rear end face after sawing is R5~R10, and the roughness of the sawn surface is Ra3.2.

[0138] Step 12) Grinding and repairing: Grind away any possible cracks, folds, sharp corners, and other defects on the forging surface and make a smooth transition, with edge chamfers of R5 to R10;

[0139] Step 13) Die forging first heating: Die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used between the upper and lower dies to raise the height by 50-100mm; the forging is heated to 440±10°C and kept warm for 640-940min;

[0140] Step 14) Die forging first fire forging: Use a 50,000-ton hydraulic press to load the die for forging. Set the zero position after the upper and lower dies are closed. Press down from a height of 370 mm to 70 mm at a pressing speed of 5 mm / s. Lift the upper die to lubricate the die cavity surface and the blank. Press down from a closing height of 80 mm at a pressing speed of 3 mm / s to a height of 20±5 mm. Measure the thickness of the extended section to 191±5 mm. Air cool or wind cool to room temperature after forging.

[0141] Step 15) Trimming: Trim according to the trimming wire frame dedicated to forgings. The burr residue after trimming is 15 to 40 mm, and the local position is allowed to be greater than 40 mm;

[0142] Step 16) Etching and repairing: Forgings are chemically etched to remove surface oil and other attachments. Any defects such as cracks, folds, sharp corners, etc. that may exist on the surface are polished and removed and rounded, with edge chamfers of R5 to R10. After polishing, they need to be etched again and the surface checked again until the defects are completely removed;

[0143] Step 17) Die forging 2-fire heating: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used between the upper and lower dies to raise the height by 50-100mm; the blank is heated to 440±10°C and kept warm for 400-580min;

[0144] Step 18) Die forging 2: Use a 50,000-ton hydraulic press to load the die for forging. Set the zero position after the upper and lower dies are closed. Press down from a height of 40 mm at a speed of 2 mm / s to a height of 6±4 mm. The thickness of the extended section is measured to be 171±5 mm. After forging, air cool or wind cool to room temperature.

[0145] Step 19) Trimming: Trim the edges according to the trimming wire frame specially used for forgings, and the residual burr after trimming is 5 to 35 mm;

[0146] Step 19) Etching and repairing: Forgings are chemically etched to remove surface oil and other attachments. Any defects such as cracks, folds, sharp corners, etc. that may exist on the surface are polished and removed and rounded, with edge chamfers of R5 to R10. After polishing, they need to be etched again and the surface checked again until the defects are completely removed;

[0147] Step 20) Dimension inspection: Perform three-dimensional scanning on each forging piece and compare it with the digital model of the forging piece to check whether there is any incomplete cavity or deformation.

[0148] Preferably, in the above step 2), the upper and lower flat anvils of the mold are heated to a fixed temperature of 400°C, heated and kept warm for more than 10 hours, and the blank is kept warm for 960 minutes.

[0149] In the step 3-1), the starting forging temperature is 415°C, the final forging temperature is 387°C, the forging scheme is upsetting to 670-690mm, and then stretched to a square Continue to upsetting to 550-570mm, then stretch to square This process completes the upsetting deformation in two directions of the original ingot.

[0150] In the step 3-2), the billet is kept warm for 828 minutes, the start forging temperature is 417°C, the final forging temperature is 387°C, the forging scheme is upsetting to 550-570 mm, and then stretched to a square Continue to lengthen and reshape to the four sides This process completes the upsetting deformation in the last direction of the original ingot.

[0151] In the step 3-3), the billet is kept warm for 300 minutes, the upper and lower flat anvils are changed to 500 mm long anvils, the start forging temperature is 417 ° C, the final forging temperature is 382 ° C, and the forging plan is chamfered and drawn to eight sides. Continue rolling until

[0152] Preferably, in the above step 9), the temperature of the 500 mm drawing anvil of the mold is set at 400° C., and the heating and heat preservation is carried out for more than 10 hours, and the blank is kept warm for 770 minutes.

[0153] Preferably, in the above step 10), the starting forging temperature is 417°C, the final forging temperature is 372°C,

[0154] Forging plan: The saw cut end is upset to 410-430mm, and then extended to four steps.

[0155] Preferably, in the above step 13), the die forging die is kept at a constant temperature of 400° C., heated and kept warm for more than 10 hours, and the blank is kept warm for 669 minutes.

[0156] Preferably, in the above step 14), a 50,000-ton die forging hydraulic press is equipped with a special die forging die, the start forging temperature is 416°C, the final forging temperature is 406°C, the two pressing processes are set at pressing speeds of 5mm / s and 3mm / s respectively, the underpressure is 23-25mm, and the pressure is 43,000 tons.

[0157] In the above step 14), a 50,000-ton die forging hydraulic press is equipped with a special die forging die, the billet is kept warm for 477 minutes, the start forging temperature is 415°C, the final forging temperature is 406°C, the pressing speed is set to 2 mm / s, the underpressure is 6 to 8 mm, and the pressure is 50,000 tons.

[0158] The above is only a specific embodiment of the present invention, and the present invention is described in detail. The unexplained part is a conventional technology. However, the protection scope of the present invention is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A forging method for a large hinge beam die forging for an aircraft, characterized in that: include: Step S01: heating before forging: the upper and lower flat anvils and the drawing anvil of the die are heated to a fixed temperature of 350-450°C and kept warm for ≥10 hours; the 7050 aluminum alloy ingot is heated to 440±10°C and kept warm for 770-1070 minutes to form a blank; Step S02: Ingot reforging: using upper and lower flat anvils and a drawing anvil, the billet is taken out of the furnace for forging after reaching the minimum holding time, and after three fires, it is upsetting and drawing to form a reforged billet; Step S03 machining: peel the outer surface of the forged blank, the surface roughness after outer circle machining is Ra6.3, the pinhole at the end needs to be polished to a smooth transition, and the grinding width-to-depth ratio is not less than 6:1; Step S04: Blank heating: the drawing anvil is heated to a fixed temperature of 350-450°C and kept at this temperature for ≥10 hours; the machined reforging blank is heated to 440±10°C and kept at this temperature for 640-940 minutes; Step S05 forging: using a drawing anvil, the heated forging blank is taken out of the furnace for forging after reaching the minimum holding time, and the forging is flattened to a preset length from the end including the sawn surface, and the remaining part is respectively drawn to three preset sizes. During the drawing process, the downward pressure is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃; Step S06: sawing: sawing the end of the forged blank after forging, the sawing length is controlled at a preset value, the edge chamfer of the rear end face is R5-R10, the sawing surface roughness is Ra3.2, and a forging is formed; Step S07: Grinding and repairing: grinding and smoothing the surface defects of the forgings, chamfering the edges R5-R10; Step S08: First heating of die forging: heating the die forging die to a fixed temperature of 420-480°C, keeping the temperature for ≥30 hours, and using a pad to raise the upper and lower dies; heating the forgings after grinding and repairing to 440±10°C, keeping the temperature for 640-940 minutes; Step S09: First die forging: forging after loading the die, setting the zero position after the upper and lower dies are closed, performing die lifting and lubrication once during the pressing process, and air cooling or wind cooling to room temperature after forging; Step S10: first trimming: trimming the forgings produced by the first forging; Step S11: First etching and repairing: etching and cleaning the forging after the first trimming, grinding and removing the surface defects and making a smooth transition, chamfering the edges R5 to R10, and etching and cleaning again after grinding, and checking the surface again until the defects are completely removed; Step S12: Die forging second heating: the die forging die is heated to a fixed temperature of 420-480°C and kept warm for ≥30 hours, and a pad is used to raise the upper and lower dies; the forging after the first etching and repair is heated to 440±10°C and kept warm for 400-580 minutes; Step S13: forging the second die forging: after loading the die, forging is performed, the upper and lower dies are closed and set to zero position, and air-cooled or wind-cooled to room temperature after forging; Step S14: second trimming: trimming the forging after the second forging; Step S15: Second etching and repairing: chemically etching the forging after the second trimming, grinding and removing the surface defects and making a smooth transition, chamfering the edges R5 to R10, and etching again after grinding, and checking the surface again until the defects are completely removed; Step S16: Dimension inspection: Dimension inspection is performed on the forging after the second etching and cleaning repair, and a large hinge beam die forging for aircraft is formed after passing the inspection.

2. The method according to claim 1, characterized in that Step S02 also includes: the first upsetting and drawing, the heating temperature is 440±10℃, the heat preservation is 340~640min, the upsetting pressing speed setting value is 5~10mm / s during the deformation process, the pressing amount during the drawing process is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃.

3. The method according to claim 1, characterized in that Step S02 also includes: second upsetting and drawing, heating temperature 440±10℃, keeping warm for 290~590min, setting value of upsetting pressing speed during deformation process 5~10mm / s, pressing amount ≤70mm and feeding amount ≤300mm during drawing process, transfer time ≤150s, start forging temperature ≥410℃, final forging temperature ≥350℃, and mold temperature ≥250℃.

4. The method according to claim 1, characterized in that: Step S02 also includes: a third time of drawing and rounding to obtain a modified forging blank, air cooling to room temperature after forging, the downward pressure during the drawing process is ≤70mm, the feed amount is ≤300mm, the transfer time is ≤150s, the start forging temperature is ≥410℃, the final forging temperature is ≥350℃, and the mold temperature is ≥250℃.

5. The method according to claim 1, characterized in that After step S03, the method further includes: According to the requirements of ASTM B594, the outer cylindrical surface of the machined forged blank is tested by contact method piece by piece, and the testing level is A.

6. The method according to claim 1, characterized in that After step S03, the method further includes: Step S031 Sampling: sawing is performed at any end of the processed forged blank, and the length of the sawing sample is ≥80mm. The samples include longitudinal tensile samples, high-magnification test blocks, fracture samples, and low-magnification test pieces. The sawing end face edge chamfers are R5-R10, and the sawing surface roughness is Ra3.2; Step S032: heat treatment of the sample: performing solution treatment and aging treatment on the sample; Step S033: Sample testing: Mechanical properties testing is performed on longitudinal tensile specimens, and acceptance is based on the performance indicators of AMS4108, where the heat treatment thickness is ≤51mm; The low-power tissue examination is carried out on a low-power test machine and is carried out in accordance with the requirements of GJB2351; High-magnification microstructure inspection is carried out on a high-magnification test machine in accordance with the requirements of GJB2351; The fracture microstructure inspection is carried out on the fracture test block according to the requirements of GJB2351.

7. The method according to claim 6, characterized in that The method for solution treating the sample in step S032 also includes: using a heat treatment furnace, loading the sample after the furnace temperature stabilizes at 476±5°C, and the sample loading distance is more than 50mm; the heating system is set at 476±5°C, and the heat preservation is 60-70min, the heating medium is air, and after the heat preservation is completed, the sample is taken out of the furnace and water-cooled, the water temperature is 33-36°C, and the transfer time is 15s.

8. The method according to claim 6, characterized in that The method for aging the sample in step S032 also includes: using a heat treatment furnace, loading the sample after the furnace temperature stabilizes at 121±5°C, and the sample loading distance is more than 50mm; the first stage of the heating system is set at a constant temperature of 121±5°C, and the temperature is kept for 360 to 370 minutes; the second stage is set at a constant temperature of 177±5°C, and the temperature is kept for 540 to 550 minutes. The heating medium is air, and the sample is cooled by air after the temperature is kept.

9. A forging die for large hinge beam die forgings for aircraft, characterized in that: The invention comprises a forging die (3), a blank making die (4) and a die forging die (5), wherein the forging die (3) further comprises a forging upper die (301) and a forging lower die (302), the blank making die (4) is used for rounding and shaping the blank into a blank (303), the blank making die (4) further comprises a blank making upper die (401) and a blank making lower die (402), the die forging die (5) comprises a die forging upper die (501), a die forging lower die (502), a die forging guide pin (503) and a die forging ejector (504), during die forging, the blank (505) is placed on the die forging lower die (502), the plane of the first platform (506) of the lower die is in contact with the plane of the large end of the blank (505) and is placed firmly, the die forging upper die (501) is pressed downward to contact the blank, the blank metal first fills the plane (506), and when it continues to flow, it is affected by the surrounding cavity and the die forging lower die (502). The metal of the blank is forced to flow toward the second platform (507), the third platform (508), the fourth platform (509), the fifth platform (510), the sixth platform (511) and the seventh platform (512) of the lower die through the lower die first slope (513), the lower die second slope (514) and the lower die third slope (515) of the lower die (502) whose depths increase in sequence; the pre-forged blank is placed in the lower die (502); under the downward pressure of the upper die (501), the metal continues to flow and fills each part of the cavity piece by piece to complete the final forging; the ejector (504) is used to eject the forging; the guide pin (503) is used to position the upper die (501) and the lower die (502) together.

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