CN117245252B - Inertia friction welding and diffusion welding composite manufacturing method for hollow turbine disk with journal - Google Patents
Inertia friction welding and diffusion welding composite manufacturing method for hollow turbine disk with journal Download PDFInfo
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- CN117245252B CN117245252B CN202311535576.3A CN202311535576A CN117245252B CN 117245252 B CN117245252 B CN 117245252B CN 202311535576 A CN202311535576 A CN 202311535576A CN 117245252 B CN117245252 B CN 117245252B
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- 238000003466 welding Methods 0.000 title claims abstract description 280
- 238000009792 diffusion process Methods 0.000 title claims abstract description 155
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- 239000002131 composite material Substances 0.000 title claims abstract description 8
- 238000004140 cleaning Methods 0.000 claims abstract description 37
- 230000032683 aging Effects 0.000 claims abstract description 17
- 238000001514 detection method Methods 0.000 claims abstract description 10
- 239000000843 powder Substances 0.000 claims abstract description 10
- 229910000601 superalloy Inorganic materials 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims description 43
- 238000000034 method Methods 0.000 claims description 39
- 238000003754 machining Methods 0.000 claims description 33
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 24
- 238000001816 cooling Methods 0.000 claims description 20
- 229910052786 argon Inorganic materials 0.000 claims description 13
- 230000007547 defect Effects 0.000 claims description 13
- 238000007599 discharging Methods 0.000 claims description 12
- 238000011049 filling Methods 0.000 claims description 12
- 238000000227 grinding Methods 0.000 claims description 12
- 229920000742 Cotton Polymers 0.000 claims description 10
- 238000005238 degreasing Methods 0.000 claims description 10
- 230000003746 surface roughness Effects 0.000 claims description 9
- 238000003825 pressing Methods 0.000 claims description 7
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 6
- 238000002679 ablation Methods 0.000 claims description 6
- 239000012459 cleaning agent Substances 0.000 claims description 6
- 239000008367 deionised water Substances 0.000 claims description 6
- 229910021641 deionized water Inorganic materials 0.000 claims description 6
- 239000012153 distilled water Substances 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 6
- 239000002904 solvent Substances 0.000 claims description 6
- 229910002804 graphite Inorganic materials 0.000 claims description 5
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- 238000002360 preparation method Methods 0.000 claims description 3
- 239000000523 sample Substances 0.000 claims description 3
- 238000005728 strengthening Methods 0.000 description 17
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- 239000011159 matrix material Substances 0.000 description 5
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- 239000000956 alloy Substances 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 238000005242 forging Methods 0.000 description 2
- 238000001513 hot isostatic pressing Methods 0.000 description 2
- 238000010275 isothermal forging Methods 0.000 description 2
- 210000001503 joint Anatomy 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K28/00—Welding or cutting not covered by any of the preceding groups, e.g. electrolytic welding
- B23K28/02—Combined welding or cutting procedures or apparatus
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/006—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass turbine wheels
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- Engineering & Computer Science (AREA)
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- Pressure Welding/Diffusion-Bonding (AREA)
Abstract
The invention belongs to the technical field of manufacturing of turbine discs of aeroengines, and particularly relates to a composite manufacturing method of inertia friction welding and diffusion welding of a hollow turbine disc with a shaft neck, which comprises the following steps: step 1: preparing a friction welding single piece; step 2: cleaning the journal and the front disk body; step 3: inertia friction welding; step 4: turning the flash; step 5: phased array ultrasonic detection; step 6: processing a rear disc body and a front disc body with a shaft neck; step 7: cleaning a front tray body and a rear tray body with a shaft neck; step 8: assembling into a furnace; step 9: diffusion welding; step 10: turning after diffusion welding; step 11: ultrasonic detection of diffusion welding; step 12: processing the appearance; step 13: and (5) aging treatment. The manufacturing method has the advantages of low cost, high efficiency, high quality and high performance of the powder superalloy hollow turbine disc with the journal.
Description
Technical Field
The invention belongs to the technical field of manufacturing of turbine discs of aeroengines, and particularly relates to a composite manufacturing method of inertia friction welding and diffusion welding of a hollow turbine disc with a shaft neck.
Background
The turbine disc is a key piece of an aeroengine, the turbine disc is generally connected with a front journal by bolts to provide power for an engine compressor rotor, and the bolt connection structure has the problems of bolt hole stress concentration, temperature stress and the like when in use, so that the stability of the structure is greatly influenced. The hollow turbine disc with the journal is a typical structure of an international advanced high-performance engine, as shown in fig. 1, and is an integrated structure of a front journal and a turbine disc, so that on one hand, a connection structure of the journal and a mounting edge of the turbine disc is omitted, and the weight of the structure is reduced; meanwhile, the temperature and structural stress of the bolt connection area are eliminated, and the tightness and reliability are improved; on the other hand, the turbine disk body with a special hollow structure utilizes the internal channel of the turbine blade to collect cooling air, and the cooling air enters the hollow area in the turbine disk through the air inlet hole at the bottom of the tongue-and-groove at the outer edge of the turbine disk, so that the internal cooling of the turbine blade and the disk body is realized, the stress state of the turbine disk is improved, the service life of the turbine disk is prolonged, and the turbine disk is one of the key development directions of an advanced high-performance engine.
The hollow turbine disk with the journal adopts powder superalloy, and the length of the journal reaches 200mm. As shown in fig. 1, the hollow cavity of the hollow turbine disk with the journal is long and narrow, the minimum distance between two webs is less than 10mm, the maximum outline dimensions of the cutter bar and the cutter for turning are both greater than 10mm, and when the hollow cavity is manufactured by turning, the hollow cavity part close to the disk edge of the turbine disk cannot be machined. The hollow turbine disk with the journal can therefore only be manufactured by means of welding. For welding of disc-shaft and disc-disc structures, inertia friction welding is the most commonly used high-efficiency manufacturing method, and the welding of the shaft neck and the disc body is easily realized by adopting inertia friction welding, but the following problems exist in the process of disc-disc welding:
(1) Inertia friction welding is a process method of rotation-contact-friction-forge welding, flash is generated in the welding process, a cavity of a hollow turbine disk is long and narrow, the minimum distance between two webs after welding is less than 10mm, the inner cavity cannot be processed after welding, and the flash cannot be removed.
(2) The welding area of the disk edge part of the hollow turbine disk is large, special large-tonnage inertia friction welding equipment is needed, and the equipment manufacturing cost is high.
(3) In the process of contact friction, the joint reaches a viscoplastic state, the highest temperature exceeds 1200 ℃, the temperature from the joint butt joint surface to the joint heat affected zone is equal to or greater than the solution heat treatment temperature of the part base material, and the original gamma' strengthening phase in the base material is dissolved back or partially dissolved back to obtain a supersaturated gamma base. The cooling speed of the inertia friction welding head is extremely high, so that the gamma ' strengthening phase is not precipitated for enough time, even though the double aging heat treatment is carried out, the gamma ' strengthening phase cannot be further promoted to grow up, and the end result is that the quantity and the size of the gamma ' strengthening phase of the inertia friction welding head are insufficient, and the strength and toughness mechanism of the inertia friction welding head is changed from precipitation phase strengthening to grain boundary strengthening, so that the durability and creep property of the joint are affected.
Therefore, the inertia friction welding cannot fully realize the manufacture of the hollow turbine disk with the shaft diameter.
Diffusion welding is also a high quality, high performance welding method, especially suitable for large area connections. Although the journalled hollow turbine disk can be directly manufactured using diffusion welding, there are the following problems:
(1) Powder superalloy billets are typically manufactured by hot isostatic pressing, isothermal forging/extrusion, and heat treatment. If the journal and the front disc are integrally formed powder superalloy blanks, as shown in fig. 2, the rear disc is a single powder superalloy blank, and diffusion welding is adopted to weld the front disc and the rear disc, then when preparing the front disc blank with the journal: 1) The hot isostatic pressing sheath has complex structure, high manufacturing cost and insufficient local static pressure deformation; 2) When isothermal forging or extrusion forming is performed, a forming die is complex, the service life is short, the whole forging deformation is large, and the local forging deformation is insufficient. Finally, the comprehensive performance of the front disc blank with the shaft diameter cannot meet the use requirement.
(2) If the journal and the front disk body are of a split structure, and the connection of the journal, the front disk body and the rear disk body is realized by adopting diffusion welding, the following exists: 1) The clamp for diffusion welding has complex structure and overlarge heat capacity, and the high-temperature residence time of parts is overlong, so that the performance damage of a matrix is increased; 2) Diffusion welding is a process method for realizing welding through contact and atomic diffusion, and the welding rate of a diffusion welding head is improved by means of thermal deformation activation and plastic deformation activation, so that the comprehensive performance of the joint is ensured; for the part, the axial height and the welding area of two diffusion welding lines of the journal and the front disc body and the rear disc body are different, and when the two welding lines are subjected to diffusion welding in the same procedure, the contact time of the surfaces to be welded of the two welding lines and the creep deformation time and the degree of a welding joint are different, so that the consistency of the welding quality and the joint performance of the two welding lines is difficult to ensure; when two welding seams are subjected to diffusion welding respectively by adopting two working procedures, the thermal cycle of the two diffusion welding working procedures aggravates the damage of the property of the base material of the part, and the final result is that the property of the part can not meet the use requirement; 3) The welding seam of the journal and the front disk body bears axial pressurizing pressure and is transmitted downwards, and a supporting block is required to be placed in the space between the webs of the front disk body and the rear disk body along the circumferential direction for preventing the front disk body from deforming downwards, so that the supporting block is difficult to select materials and place around the whole circumference.
Therefore, the direct use of diffusion welding to manufacture hollow turbine disks with shaft diameters is not an optimal option.
Disclosure of Invention
The invention aims to provide a composite manufacturing method of inertia friction welding and diffusion welding of a hollow turbine disk with a journal, which adopts the process route of inertia friction welding of the journal and a front disk body, turning and removing of inertia friction welding flash, phased array ultrasonic detection of an inertia friction welding seam, outer shape processing of the front disk body, diffusion welding of the front disk body and a rear disk body with the journal, turning processing after diffusion welding, ultrasonic detection of the diffusion welding seam, appearance processing and aging treatment to realize low-cost, high-efficiency, high-quality and high-performance manufacturing of the hollow turbine disk with the journal of a powder high-temperature alloy.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
a composite manufacturing method of inertia friction welding and diffusion welding of a hollow turbine disc with a shaft neck comprises the following steps:
step 1: friction welding single piece preparation
The journal, the front disk body and the rear disk body are made of forged powder superalloy, wherein the journal is a single piece with allowance;
step 2: cleaning
Firstly, degreasing treatment is carried out, and then, the journal and the front disk body are put into a cleaning machine for cleaning;
step 3: inertia friction welding
Inertia friction welding is carried out on the journal and the front disk body by adopting an inertia friction welding machine, and the shrinkage is 2 mm-6 mm;
step 4: vehicle flash
Removing inner and outer burrs of the friction welding head on the front disc body side and the friction welding head on the journal side after inertia friction welding by adopting machining;
step 5: phased array ultrasonic inspection
Adopting phased array ultrasonic to detect the defects of the welding line, detecting the outer circular surface of the whole welding line by a detection probe from the outer side, detecting the defects in the welding line, and if the defects in the welding line meet the design standard, carrying out the next step; if the internal defects of the welding line do not meet the standard, the welding line is directly scrapped;
step 6: rear disc body and front disc body processing with shaft neck
Machining the outer surfaces of the rear disc body and the front disc body with the shaft neck by adopting a vehicle, and reserving machining allowance of 0.3 mm-0.5 mm at the positions of the surface to be welded of the front disc body and the surface to be welded of the rear disc body by diffusion welding; adopting grinding to process the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded, so that the flatness and the parallelism of the front disc body datum surface, the rear disc body datum surface, the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded are less than or equal to 0.03mm; finish machining is carried out on the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded by adopting precise grinding, so that the surface roughness of the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded is less than or equal to 0.4 mu m, and the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded are free from burn, ablation and other heterogeneity;
step 7: cleaning
Firstly, degreasing, and then putting the rear disc body and the front disc body with the shaft neck into a cleaning machine for cleaning;
step 8: assembled into furnace
Aligning and attaching two to-be-welded parts of the rear disc body and the front disc body with the shaft neck, positioning by adopting a positioning pin to form a to-be-welded assembly, and checking that the gap between the to-be-welded surface of the front disc body and the to-be-welded surface of the rear disc body in diffusion welding is less than or equal to 0.02mm; placing a lower die on a diffusion welding equipment platform, placing a to-be-welded assembly on the lower die, then arranging graphite limiting columns around the to-be-welded assembly, and then enabling a diffusion welding equipment pressing plate to descend along with an upper die to compress the to-be-welded assembly; finally, placing the end of the diffusion welding equipment load thermocouple outside the part to be welded of the component to be welded, and keeping contact; closing a furnace door, and vacuumizing the furnace;
step 9: diffusion welding
Adjusting the pressure of diffusion welding equipment and heating; continuously adjusting the pressure of the diffusion welding equipment and maintaining the pressure, and after the diffusion welding is finished, enabling the pressure plate of the diffusion welding equipment to lift up with the upper die until the lower edge of the upper die is higher than the end face of the shaft neck; filling high-purity argon, starting a fan to cool the welded assembly, then closing the fan and the argon filling system to cool the welded assembly along with the furnace, and discharging the welded assembly after cooling;
step 10: diffusion post-weld turning
Machining the front disc body reference surface and the rear disc body reference surface by adopting machining so that the surface roughness of the front disc body reference surface and the rear disc body reference surface is less than or equal to 1.6 mu m;
step 11: ultrasonic detection for diffusion welding
Adopting high-frequency ultrasonic waves to check the welding quality of the diffusion welding seam, and carrying out the next step if the diffusion welding seam is qualified; the unqualified product is directly scrapped;
step 12: contour machining
Processing the shape after butt welding to enable the shape to accord with a design drawing;
step 13: aging treatment
And (5) carrying out ageing treatment on the welded assembly by adopting a secondary ageing vacuum heat treatment method, and discharging the welded assembly after furnace cooling to below 80 ℃.
The step 2 is specifically as follows: degreasing with absorbent cotton or white cotton cloth; during cleaning, deionized water, distilled water, water-based cleaning agent or alcohol is selected as the cleaning solvent, and no water stain is left on the journal and the front disk body after cleaning.
The step 7 is specifically as follows: degreasing with absorbent cotton or white cotton cloth; during cleaning, the front tray body diffusion welding surface to be welded and the rear tray body diffusion welding surface to be welded are placed upwards; the cleaning solvent is deionized water, distilled water, water-based cleaning agent or alcohol, and no water stain residue exists on the front disc diffusion welding surface to be welded and the rear disc diffusion welding surface to be welded after cleaning.
Step 9, the diffusion welding comprises the following specific processes:
adjusting the pressure of diffusion welding equipment to enable the welding pressure to be 0.1MPa; heating at a heating rate of not more than 15 ℃/min, observing the temperature rise of the load thermocouple to 800+/-10 ℃, and preserving heat for 60min; heating at a heating rate of not more than 15 ℃/min, observing the temperature of the load thermocouple to rise to 1030+/-10 ℃, and preserving heat for 60min; heating is continued at a heating rate of not more than 10 ℃/min, the temperature of the load thermocouple is observed to rise to 1130+/-10 ℃ to 1150+/-10 ℃, and the temperature is kept for 60 to 90 minutes;
adjusting the pressure of the diffusion welding equipment to be 0.5-0.8 MPa, maintaining the pressure for 30-40 min, then adjusting the pressure of the diffusion welding equipment to be 1.5-2.5 MPa, maintaining the pressure for 30-40 min, and finally adjusting the pressure of the diffusion welding equipment to be 4-5 MPa, and maintaining the pressure for 30-40 min;
after the heat preservation is finished, the pressure plate of the diffusion welding equipment is lifted up with the upper die until the lower edge of the upper die is higher than the end face of the shaft neck; filling high-purity argon with the pressure of 4bar to 6bar, starting a fan to cool the welded assembly to below 400 ℃, and then closing the fan and an argon filling system to cool the welded assembly to below 80 ℃ along with the furnace to discharge;
the step 13 secondary aging vacuum heat treatment method specifically comprises the following steps: the heat treatment temperature is 815+/-10 ℃ to 845+/-10 ℃, the heat preservation is carried out for 240 to 480 minutes, and the furnace is cooled to below 80 ℃ and is discharged; preserving heat for 480-960 min at 760+ -10 ℃, cooling to below 80 ℃ and discharging.
The beneficial effects of the invention are as follows:
aiming at the defects that the existing manufacturing method cannot realize the manufacturing of the hollow turbine disk with the journal, and fully utilizing the advantages and disadvantages of the two welding methods of inertia friction welding and vacuum diffusion welding in structural adaptability, connection performance and processing efficiency, the invention provides a composite manufacturing method of inertia friction welding and diffusion welding of the hollow turbine disk with the journal, which not only can solve the problem of insufficient separation of a welding line gamma' caused by large supercooling degree during cooling of the inertia friction welding line, but also can avoid the problems of increased matrix performance damage, unstable welding quality and performance during diffusion welding of a plurality of welding lines with different axial heights and welding areas, so that the manufacturing technical difficulty and waste risk of parts are reduced by about 30 percent, and the manufacturing difficulty and cost of blanks are reduced by about 20 percent, thereby realizing the low-cost, high-efficiency, high-quality and high-performance manufacturing of the hollow turbine disk with the journal by powder high-temperature alloy.
Drawings
FIG. 1 is a schematic view of the hollow turbine disk structure with journals of the present invention;
FIG. 2 is a schematic view of a journaled front disc of the present invention;
FIG. 3 is a schematic illustration of a single piece of a journal of the present invention;
FIG. 4 is a schematic view of a single front tray of the present invention;
FIG. 5 is a schematic diagram of the invention before flashing;
FIG. 6 is a schematic view of the invention after flashing;
FIG. 7 is a schematic view of a single piece of the rear tray of the present invention;
FIG. 8 is a schematic view of the assembly of a journaled hollow turbine disk of the present invention into a furnace;
FIG. 9 is a cross-sectional view of the journaled hollow turbine disk assembly of the present invention;
reference numerals: the welding device comprises a front disc body, a rear disc body, a 3-journal, a 4-journal side friction welding head, a 5-front disc body side friction welding head, a 6-front disc body diffusion welding surface to be welded, a 7-front disc body reference surface, an 8-rear disc body diffusion welding surface to be welded, a 9-rear disc body reference surface, a 10-diffusion welding equipment platform, a 11-lower die, a 12-upper die, a 13-graphite limiting column and a 14-diffusion welding equipment pressing plate.
Detailed Description
The invention is described in further detail below with reference to the drawings and examples.
Embodiment 1, a method for manufacturing a hollow turbine disk with a journal by combining inertia friction welding and diffusion welding, comprising the following steps:
step 1: friction welding single piece preparation
The journal 3, the front disc body 1 and the rear disc body 2 are made of forged powder superalloy in one piece, as shown in fig. 3 and 4, wherein the journal 3 is a single piece with allowance, the journal side friction welding head 4 is shown in fig. 3, and the front disc body side friction welding head 5 is shown in fig. 4;
step 2: cleaning
Degreasing with absorbent cotton or cotton cloth, and cleaning the journal 3 and the front disk 1 in a cleaner; during cleaning, deionized water, distilled water, water-based cleaning agent or alcohol is selected as a cleaning solvent, and no water stain residue exists on the journal 3 and the front disk body 1 after cleaning;
step 3: inertia friction welding
Inertia friction welding is carried out on the journal 3 and the front disk body 1 by adopting an inertia friction welding machine, and the shrinkage is 2mm;
step 4: vehicle flash
Removing inner and outer burrs of the front disc body side friction welding head 5 and the journal side friction welding head 4 after inertia friction welding by adopting machining, as shown in fig. 5 and 6;
step 5: phased array ultrasonic inspection
Adopting phased array ultrasonic to detect the defects of the welding line, and detecting the defects inside the welding line by detecting the outer circular surface of the whole welding line from the outer side by a detection probe; if the internal defects of the welding line meet the design standard, carrying out the next step; if the internal defects of the welding line do not meet the standard, the welding line is directly scrapped;
step 6: rear disc 2 and front disc 1 with journal 3
Machining the appearance surface of the front disc body 1 with the shaft neck 3 by adopting turning, reserving 0.5mm machining allowance at the position of the front disc body diffusion welding surface 6 to be welded, and machining the front disc body diffusion welding surface 6 by adopting grinding, so that the flatness and the parallelism of the front disc body reference surface 7 and the front disc body diffusion welding surface 6 are less than or equal to 0.03mm; finish machining of the front disc body diffusion welding surface 6 is carried out by adopting precise grinding, so that the surface roughness of the front disc body diffusion welding surface 6 is less than or equal to 0.4 mu m, and the front disc body diffusion welding surface 6 is free from burn, ablation and other heterogeneity; as shown in fig. 2;
machining the outer surface of the rear tray body 2 by adopting a turning machine, reserving a machining allowance of 0.5mm at the position of the surface 8 to be welded of the rear tray body diffusion welding, and machining the surface 8 to be welded of the rear tray body diffusion welding by adopting a grinding machine, so that the flatness and the parallelism of the reference surface 9 of the rear tray body and the surface 8 to be welded of the rear tray body diffusion welding are less than or equal to 0.03mm; finish machining of the surface 8 to be welded of the rear disc body diffusion welding is carried out by adopting precise grinding, so that the surface roughness of the surface 8 to be welded of the rear disc body diffusion welding is less than or equal to 0.4 mu m, and the surface 8 to be welded of the rear disc body diffusion welding has no burn, ablation or other heterogeneity; as shown in fig. 7;
step 7: cleaning
Degreasing with absorbent cotton or cotton cloth, cleaning the rear tray body 2 and the front tray body 1 with the shaft neck 3 in a cleaning machine, and placing the front tray body diffusion welding surface 6 and the rear tray body diffusion welding surface 8 upwards during cleaning; the cleaning solvent is deionized water, distilled water, water-based cleaning agent or alcohol, and no water stain residue exists on the front disc diffusion welding surface 6 and the rear disc diffusion welding surface 8 after cleaning;
step 8: assembled into furnace
The component diffusion welding adopts a vacuum diffusion welding furnace, the Z-axis height is more than 700mm, and the maximum argon filling cooling pressure is not less than 4bar; aligning and attaching two to-be-welded parts of the rear disc body 2 and the front disc body 1 with the shaft neck 3, positioning by adopting a positioning pin to form a to-be-welded assembly, and checking that the gap between the to-be-welded surface 6 of the front disc body and the to-be-welded surface 8 of the rear disc body is less than or equal to 0.02mm; placing a lower die 11 on a diffusion welding equipment platform 10, placing a component to be welded on the lower die, and then arranging graphite limiting columns 13 around the component to be welded, wherein the graphite limiting columns 13 are lower than the upper surface of an upper die 12 by 0.08+/-0.03 mm, and then enabling a diffusion welding equipment pressing plate 14 to be lowered together with the upper die 12 to press the component to be welded, wherein the upper die 12 and the diffusion welding equipment pressing plate 14 are connected in a hanging mode; finally, placing the end of the diffusion welding equipment load thermocouple outside the part to be welded of the component to be welded, and keeping contact; the final assembly effect is shown in fig. 8 and 9; closing the furnace door, and vacuumizing until the vacuum pressure in the furnace is less than 1 multiplied by 10 -4 mbar；
Step 9: diffusion welding
Adjusting the pressure of diffusion welding equipment to enable the welding pressure to be 0.1MPa; heating at a heating rate of not more than 15 ℃/min, observing the temperature rise of the load thermocouple to 800+/-10 ℃, and preserving heat for 60min; heating at a heating rate of not more than 15 ℃/min, observing the temperature of the load thermocouple to rise to 1030+/-10 ℃, and preserving heat for 60min; heating at a heating rate of not more than 10 ℃/min, observing the temperature of the load thermocouple to rise to 1130+/-10 ℃, and preserving heat for 60min;
adjusting the pressure of the diffusion welding equipment to enable the welding pressure to be 0.8MPa, keeping the welding pressure for 40min, then adjusting the pressure of the diffusion welding equipment to enable the welding pressure to be 2.5MPa, keeping the welding pressure for 40min, and finally adjusting the pressure of the diffusion welding equipment to enable the welding pressure to be 5MPa, and keeping the welding pressure for 40min;
after the heat preservation is finished, the diffusion welding equipment pressing plate 14 is lifted up with the upper die 12 until the lower edge of the upper die 12 is higher than the end face of the shaft neck 3; filling 4bar high-purity argon, starting a fan to cool the welded assembly to below 400 ℃, and then closing the fan and an argon filling system to cool the welded assembly to below 80 ℃ along with the furnace and discharging;
when the inertia friction welding is adopted to weld the journal 3 and the front disk body 1, as the inertia friction welding is a connecting method of rotating energy storage, contact friction and upsetting welding, the joint reaches a viscoplastic state in the contact friction process, the highest temperature exceeds 1200 ℃, the temperature from the joint butt joint surface to the joint heat affected zone is equal to or higher than the solution heat treatment temperature of the part base material, and the original gamma' strengthening phase in the base material is dissolved back or partially dissolved back to obtain a supersaturated gamma base. For the solid solution heat treatment process of the matrix material, the re-dissolution or partial re-dissolution of the gamma '-strengthening phase is a necessary aim, gamma' -strengthening phases with different sizes and numbers can be obtained through controlling the cooling speed, but for the inertia friction welding, the cooling speed is extremely high, so that the gamma '-strengthening phase is not precipitated for a sufficient time, even though the gamma' -strengthening phase is subjected to double aging heat treatment, the gamma '-strengthening phase cannot be further promoted to grow up, and the final result is that the quantity and the size of the gamma' -strengthening phase of the inertia friction welding head are insufficient, the strength and toughness mechanism of the inertia friction welding head is changed from precipitation phase strengthening to grain boundary strengthening, and the durability and creep property of the joint are affected;
the invention utilizes the vacuum diffusion welding furnace with gas quenching cooling capacity, realizes the diffusion welding of the front and rear disk bodies, simultaneously further adjusts and modulates the inertia friction welding head in the previous working procedure, creates reasonable supercooling degree for the precipitation of gamma 'strengthening phases in the inertia friction welding head by simulating the solid solution treatment cooling speed of a matrix material, and ensures the quantity and the size of the gamma' strengthening phases in the inertia friction welding head, thereby improving the durability and the creep property of the inertia friction welding head and improving the stretching and fatigue properties of the joint to a certain extent;
step 10: diffusion post-weld turning
Machining the front disc body reference surface 7 and the rear disc body reference surface 9 by adopting a turning machine, so that the surface roughness of the front disc body reference surface 7 and the rear disc body reference surface 9 is less than or equal to 1.6 mu m;
step 11: ultrasonic detection for diffusion welding
Adopting high-frequency ultrasonic waves to check the welding quality of the diffusion welding seam, and carrying out the next step if the diffusion welding seam is qualified; the unqualified product is directly scrapped;
step 12: contour machining
Processing the shape after butt welding to enable the shape to accord with a design drawing;
step 13: aging treatment
Adopting a secondary aging vacuum heat treatment method, wherein the heat treatment temperature is 815+/-10 ℃, preserving heat for 240min, cooling to below 80 ℃ and discharging; preserving heat for 960min at 760+/-10 ℃, cooling to below 80 ℃ and discharging; the separation and growth of gamma' phase are further promoted by a secondary aging vacuum heat treatment method, so that the comprehensive performance of the weldment joint and the matrix material is improved.
In example 2, steps 1 to 2, steps 4 to 5, steps 7 to 8, and steps 10 to 12 are the same as in example 1, and the other processes are as follows:
step 3: inertia friction welding
And inertia friction welding is carried out on the journal 3 and the front disk body 1 by adopting an inertia friction welding machine, and the shrinkage is 6mm.
Step 6: rear disc 2 and front disc 1 with journal 3
Machining the appearance surface of the front disc body 1 with the shaft neck 3 by adopting turning, reserving 0.3mm machining allowance at the position of the front disc body diffusion welding surface 6 to be welded, and machining the front disc body diffusion welding surface 6 by adopting grinding, so that the flatness and the parallelism of the front disc body reference surface 7 and the front disc body diffusion welding surface 6 are less than or equal to 0.03mm; finish machining of the front disc body diffusion welding surface 6 is carried out by adopting precise grinding, so that the surface roughness of the front disc body diffusion welding surface 6 is less than or equal to 0.4 mu m, and the front disc body diffusion welding surface 6 is free from burn, ablation and other heterogeneity;
machining the outer surface of the rear tray body 2 by adopting a turning machine, reserving a machining allowance of 0.3mm at the position of the surface 8 to be welded of the rear tray body diffusion welding, and machining the surface 8 to be welded of the rear tray body diffusion welding by adopting a grinding machine, so that the flatness and the parallelism of the reference surface 9 of the rear tray body and the surface 8 to be welded of the rear tray body diffusion welding are less than or equal to 0.03mm; and the surface 8 to be welded of the rear disc body is subjected to final machining by adopting precise grinding, so that the surface roughness of the surface 8 to be welded of the rear disc body is less than or equal to 0.4 mu m, and the surface 8 to be welded of the rear disc body is free from burn, ablation and other heterogeneity.
Step 9: diffusion welding
Adjusting the pressure of diffusion welding equipment to enable the welding pressure to be 0.1MPa; heating at a heating rate of not more than 15 ℃/min, observing the temperature rise of the load thermocouple to 800+/-10 ℃, and preserving heat for 60min; heating at a heating rate of not more than 15 ℃/min, observing the temperature of the load thermocouple to rise to 1030+/-10 ℃, and preserving heat for 60min; heating at a heating rate of not more than 10 ℃/min, observing the temperature of the load thermocouple to rise to 1150+/-10 ℃, and preserving heat for 90 min;
adjusting the pressure of the diffusion welding equipment to enable the welding pressure to be 0.5MPa, keeping for 30min, then adjusting the pressure of the diffusion welding equipment to enable the welding pressure to be 1.5MPa, keeping for 30min, and finally adjusting the pressure of the diffusion welding equipment to enable the welding pressure to be 4MPa, keeping for 30min;
after the heat preservation is finished, the diffusion welding equipment pressing plate 14 is lifted up with the upper die 12 until the lower edge of the upper die 12 is higher than the end face of the shaft neck 3, 6bar of high-purity argon is filled, a fan is started to cool the weldment to below 400 ℃, and then the fan and the argon filling system are closed, so that the weldment is cooled to below 80 ℃ along with the furnace and discharged.
Step 13: aging treatment
Adopting a secondary aging vacuum heat treatment method, wherein the heat treatment temperature is 845+/-10 ℃, preserving heat for 480 minutes, cooling to below 80 ℃ and discharging; preserving heat for 480min at 760+/-10 ℃, cooling to below 80 ℃ and discharging.
Claims (5)
1. A composite manufacturing method of inertia friction welding and diffusion welding of a hollow turbine disk with a shaft neck is characterized in that,
the method comprises the following steps:
step 1: friction welding single piece preparation
The journal, the front disk body and the rear disk body are made of forged powder superalloy, wherein the journal is a single piece with allowance;
step 2: cleaning
Firstly, degreasing treatment is carried out, and then, the journal and the front disk body are put into a cleaning machine for cleaning;
step 3: inertia friction welding
Inertia friction welding is carried out on the journal and the front disk body by adopting an inertia friction welding machine, and the shrinkage is 2 mm-6 mm;
step 4: vehicle flash
Removing inner and outer burrs of the friction welding head on the front disc body side and the friction welding head on the journal side after inertia friction welding by adopting machining;
step 5: phased array ultrasonic inspection
Adopting phased array ultrasonic to detect the defects of the welding line, detecting the outer circular surface of the whole welding line by a detection probe from the outer side, detecting the defects in the welding line, and if the defects in the welding line meet the design standard, carrying out the next step; if the internal defects of the welding line do not meet the standard, the welding line is directly scrapped;
step 6: rear disc and front disc processing with journal
Machining the outer surfaces of the rear disc body and the front disc body with the shaft neck by adopting a vehicle, and reserving machining allowance of 0.3 mm-0.5 mm at the positions of the surface to be welded of the front disc body and the surface to be welded of the rear disc body by diffusion welding; adopting grinding to process the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded, so that the flatness and the parallelism of the front disc body datum surface, the rear disc body datum surface, the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded are less than or equal to 0.03mm; finish machining is carried out on the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded by adopting precise grinding, so that the surface roughness of the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded is less than or equal to 0.4 mu m, and the front disc body diffusion welding surface to be welded and the rear disc body diffusion welding surface to be welded are free from burn, ablation and other heterogeneity;
step 7: cleaning
Firstly, degreasing, and then putting the rear disc body and the front disc body with the shaft neck into a cleaning machine for cleaning;
step 8: assembled into furnace
Aligning and attaching two to-be-welded parts of the rear disc body and the front disc body with the shaft neck, positioning by adopting a positioning pin to form a to-be-welded assembly, and checking that the gap between the to-be-welded surface of the front disc body and the to-be-welded surface of the rear disc body in diffusion welding is less than or equal to 0.02mm; placing a lower die on a diffusion welding equipment platform, placing a to-be-welded assembly on the lower die, then arranging graphite limiting columns around the to-be-welded assembly, and then enabling a diffusion welding equipment pressing plate to descend along with an upper die to compress the to-be-welded assembly; finally, placing the end of the diffusion welding equipment load thermocouple outside the part to be welded of the component to be welded, and keeping contact; closing a furnace door, and vacuumizing the furnace;
step 9: diffusion welding
Adjusting the pressure of diffusion welding equipment and heating; continuously adjusting the pressure of the diffusion welding equipment and maintaining the pressure, and after the diffusion welding is finished, enabling the pressure plate of the diffusion welding equipment to lift up with the upper die until the lower edge of the upper die is higher than the end face of the shaft neck; filling high-purity argon, starting a fan to cool the welded assembly, then closing the fan and the argon filling system to cool the welded assembly along with the furnace, and discharging the welded assembly after cooling;
step 10: diffusion post-weld turning
Machining the front disc body reference surface and the rear disc body reference surface by adopting machining so that the surface roughness of the front disc body reference surface and the rear disc body reference surface is less than or equal to 1.6 mu m;
step 11: ultrasonic detection for diffusion welding
Adopting high-frequency ultrasonic waves to check the welding quality of the diffusion welding seam, and carrying out the next step if the diffusion welding seam is qualified; the unqualified product is directly scrapped;
step 12: contour machining
Processing the shape after butt welding to enable the shape to accord with a design drawing;
step 13: aging treatment
And (5) carrying out ageing treatment on the welded assembly by adopting a secondary ageing vacuum heat treatment method, and discharging the welded assembly after furnace cooling to below 80 ℃.
2. The method for manufacturing the hollow turbine disk with the journal by combining inertia friction welding and diffusion welding according to claim 1, wherein the method comprises the following steps of:
the step 2 is specifically as follows: degreasing with absorbent cotton; during cleaning, deionized water, distilled water, water-based cleaning agent or alcohol is selected as the cleaning solvent, and no water stain is left on the journal and the front disk body after cleaning.
3. The method for manufacturing the hollow turbine disk with the journal by combining inertia friction welding and diffusion welding according to claim 1, wherein the method comprises the following steps of:
the step 7 is specifically as follows: degreasing with absorbent cotton; during cleaning, the front tray body diffusion welding surface to be welded and the rear tray body diffusion welding surface to be welded are placed upwards; the cleaning solvent is deionized water, distilled water, water-based cleaning agent or alcohol, and no water stain residue exists on the front disc diffusion welding surface to be welded and the rear disc diffusion welding surface to be welded after cleaning.
4. The method for manufacturing the hollow turbine disk with the journal by combining inertia friction welding and diffusion welding according to claim 1, wherein the method comprises the following steps of:
step 9, the diffusion welding comprises the following specific processes:
adjusting the pressure of diffusion welding equipment to enable the welding pressure to be 0.1MPa; heating at a heating rate of not more than 15 ℃/min, observing the temperature rise of the load thermocouple to 800+/-10 ℃, and preserving heat for 60min; heating at a heating rate of not more than 15 ℃/min, observing the temperature of the load thermocouple to rise to 1030+/-10 ℃, and preserving heat for 60min; heating is continued at a heating rate of not more than 10 ℃/min, the temperature of the load thermocouple is observed to rise to 1130+/-10 ℃ to 1150+/-10 ℃, and the temperature is kept for 60 to 90 minutes;
adjusting the pressure of the diffusion welding equipment to be 0.5-0.8 MPa, maintaining the pressure for 30-40 min, then adjusting the pressure of the diffusion welding equipment to be 1.5-2.5 MPa, maintaining the pressure for 30-40 min, and finally adjusting the pressure of the diffusion welding equipment to be 4-5 MPa, and maintaining the pressure for 30-40 min;
after the heat preservation is finished, the pressure plate of the diffusion welding equipment is lifted up with the upper die until the lower edge of the upper die is higher than the end face of the shaft neck; and (3) filling high-purity argon with the pressure of 4bar to 6bar, starting a fan to cool the welded assembly to below 400 ℃, and then closing the fan and an argon filling system to cool the welded assembly to below 80 ℃ along with the furnace and discharging the welded assembly.
5. The method for manufacturing the hollow turbine disk with the journal by combining inertia friction welding and diffusion welding according to claim 1, wherein the method comprises the following steps of:
the step 13 secondary aging vacuum heat treatment method specifically comprises the following steps: the heat treatment temperature is 815+/-10 ℃ to 845+/-10 ℃, the heat preservation is carried out for 240 to 480 minutes, and the furnace is cooled to below 80 ℃ and is discharged; preserving heat for 480-960 min at 760+ -10 ℃, cooling to below 80 ℃ and discharging.
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