CN110899896B - Welding fixture and method for brazing large-size aluminum alloy curved surface skin and ribbed framework structure - Google Patents
Welding fixture and method for brazing large-size aluminum alloy curved surface skin and ribbed framework structure Download PDFInfo
- Publication number
- CN110899896B CN110899896B CN201911261094.7A CN201911261094A CN110899896B CN 110899896 B CN110899896 B CN 110899896B CN 201911261094 A CN201911261094 A CN 201911261094A CN 110899896 B CN110899896 B CN 110899896B
- Authority
- CN
- China
- Prior art keywords
- aluminum alloy
- brazing
- welding
- skin
- ribbed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
- B23K3/00—Tools, devices, or special appurtenances for soldering, e.g. brazing, or unsoldering, not specially adapted for particular methods
- B23K3/08—Auxiliary devices therefor
- B23K3/087—Soldering or brazing jigs, fixtures or clamping means
-
- 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
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/0008—Soldering, e.g. brazing, or unsoldering specially adapted for particular articles or work
-
- 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
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/06—Soldering, e.g. brazing, or unsoldering making use of vibrations, e.g. supersonic vibrations
-
- 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
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
-
- 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
- B23K3/00—Tools, devices, or special appurtenances for soldering, e.g. brazing, or unsoldering, not specially adapted for particular methods
- B23K3/04—Heating appliances
-
- 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
- B23K2103/00—Materials to be soldered, welded or cut
- B23K2103/08—Non-ferrous metals or alloys
- B23K2103/10—Aluminium or alloys thereof
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
Abstract
The invention discloses a welding fixture and a method for brazing a large-size aluminum alloy curved surface skin and a ribbed framework structure, and relates to the welding fixture and the method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure. The invention aims to solve the problem that the existing brazing method is not suitable for brazing large-size aluminum alloy curved surface skin and ribbed framework structure or deformation of a brazed component. The welding fixture comprises a heat-insulating layer, a heating blanket, a limiting die, a die pull rod, a pressurizing gasket and a pressurizing screw rod. The method comprises the following steps: and carrying out pre-welding heat treatment on the aluminum alloy skin and the ribbed framework, polishing and cleaning, coating brazing filler metal, and then brazing by using a welding fixture. The invention has the advantages of large size of the weldable member, reduced deformation of the workpiece in the welding process and high welding precision. The invention is applied to the field of aluminum alloy brazing.
Description
Technical Field
The invention relates to a welding fixture and a method for brazing a large-size aluminum alloy curved surface skin and a ribbed framework structure.
Background
The aluminum alloy has excellent comprehensive properties such as high strength, low density, good thermal conductivity, strong machinability and the like, and is widely applied to the fields of automobiles, aerospace, electronics and the like. On the basis of guaranteeing structural strength, for further meeting the demand of lightweight development, many parts are designed into the hollow structure who has the sealed cavity characteristic, and one side of cavity is the web that has interior muscle skeleton texture with great ease, and the opposite side is the covering, and the two combines integratively through the welded form. In addition, such a closed cavity often has a curved surface structure with a certain curvature, in addition to a common flat plate structure, that is, a curved surface skin is welded on a web plate of a ribbed skeleton structure with a corresponding curvature.
Structurally, the welding of the aluminum alloy skin and the ribbed framework structure is formed by multiple points/multiple lines, the shape of a welding joint surface is complex, and when a component has a certain size, the actual welding area is large, the welding process is complex, and the welding difficulty is high. Common fusion welding methods, such as laser welding, TIG welding and the like, cannot be applied to the welding structure; solid-phase welding methods such as resistance welding and diffusion welding are not suitable for the conditions of large components and large welding area; the conventional brazing method is difficult and heavy in solving the surface oxidation film of the aluminum alloy and promoting the wetting of the brazing filler metal and the base metal, and is easy to cause component deformation. Thus, there are currently few reports of viable, reliable welding techniques in this regard.
Disclosure of Invention
The invention aims to solve the problem that the existing brazing method is not suitable for brazing large-size aluminum alloy curved surface skin and a ribbed framework structure or deformation of a brazed component is caused, and provides a brazing method for the large-size aluminum alloy curved surface skin and the ribbed framework structure.
The welding fixture is of a semicircular pipe structure and comprises a heat insulation layer, a heating blanket, a limiting mould, a mould pull rod, a pressurizing gasket and a pressurizing screw rod; the inner surface of the heat-insulating layer is attached with a heating blanket, and the heating blanket is coated on the outer surface of the limiting mould; a plurality of mould pull rods are horizontally arranged on the upper edge of the limiting mould at intervals in parallel, two pressurizing screw rods are in threaded connection with the lower part of each mould pull rod, and the lower ends of the two pressurizing screw rods are fixedly connected with pressurizing gaskets.
The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure by using the welding fixture comprises the following steps of:
firstly, performing pre-welding heat treatment on an aluminum alloy skin and a ribbed framework;
secondly, polishing and cleaning the aluminum alloy skin and the ribbed framework after heat treatment before welding;
marking a position to be welded on the aluminum alloy skin subjected to heat treatment;
fourthly, coating the brazing filler metal on the aluminum alloy skin and the ribbed framework respectively: placing the aluminum alloy skin on a heating table for heating, and coating brazing filler metal on the position to be welded determined in the third step after the preset temperature is reached; placing the ribbed framework on a heating table for heating, and coating brazing filler metal on the surface of the stud of the ribbed framework after the preset temperature is reached; in the brazing filler metal coating process, an ultrasonic electric soldering iron is used for applying vibration to the position where the brazing filler metal is coated, the frequency range of the ultrasonic electric soldering iron applying vibration is 15kHz-60kHz, and the output power range is 20W-500W;
fifthly, performing combined welding on the aluminum alloy skin and the ribbed framework: after the aluminum alloy skin pre-coated with the brazing filler metal and the ribbed framework are cooled, accurately assembling the aluminum alloy skin and the ribbed framework to form a workpiece to be welded, then placing the workpiece into a limiting die of a welding fixture, wrapping a heating blanket outside the limiting die, wherein a heat insulation layer is arranged outside the heating blanket, a pressurizing screw rod is in threaded connection with a die pull rod, and a pressurizing gasket is arranged between the pressurizing screw rod and the workpiece to be welded; screwing a pressurizing screw to apply pressure to the workpiece to be welded; heating the workpiece to be welded by using a heating blanket, preserving heat for 5-10min after the heating temperature reaches the preset welding temperature, and increasing the pressure of a pressurizing screw on the workpiece to be welded; then, an electric hammer is adopted to apply impact vibration to the position of the pressurizing gasket, the impact frequency is 50-6000 times/min, and the impact power is 50-200W; and then stopping heating, keeping the pressure applied by the pressurizing screw to the workpiece to be welded, cooling, and dismounting the welding fixture to finish welding.
In the process of coating the brazing filler metal on the aluminum alloy skin and the ribbed framework, the oxide film on the surface of the base metal is removed by using the acoustic cavitation generated by the ultrasonic electric iron in the molten brazing filler metal, so that the wetting combination of the brazing filler metal and the base metal is realized. Electric impact vibration is applied in the welding process, the oxide film on the surface of the liquid brazing filler metal is damaged by mechanical impact vibration, the fusion of the skin surface and the liquid brazing filler metal on the surface of the stud is promoted, the oxide film residue is eliminated, the formation of impurities is avoided, and the skin and the ribbed framework are well connected. The application of mechanical vibration can reduce the welding temperature and avoid the problems of large deformation of the joint, easy generation of pores and softening of base material tissues. In addition, a limiting die suitable for curved surface welding parts is designed, and the limiting die is matched with a pressurizing mechanism, so that the accurate positioning of a workpiece to be welded can be realized, the workpiece is prevented from generating obvious deformation, and the precision of combined welding is ensured.
The invention has the following beneficial effects:
1. the welding can be carried out in the atmospheric environment, the vacuum welding environment or gas protection is not needed, and the size and the shape of the weldable component are large and are not limited greatly.
2. The mechanical vibration can be assisted to rapidly break an oxide film which prevents the brazing filler metal and the base metal from being combined in a wetting mode, chemical brazing flux which is needed in the conventional brazing process is not needed, the welding speed is high, the efficiency is high, and the environmental pollution is avoided.
3. The mechanical vibration can improve the fluidity of the brazing filler metal and accelerate the fusion, thereby reducing the welding temperature. The welding temperature is reduced, so that the heat damage of the aluminum alloy base metal can be reduced, the deformation of the workpiece in the welding process is reduced, and the welding precision is high. In addition, the limiting die suitable for the curved-surface welding part is designed, so that the deformation of the workpiece can be further reduced. The 2A12 aluminum alloy skin and the ribbed web are brazed by the method, the appearance is regular after the brazing, the brazing seam is well formed, the deformation of the outer diameters of the large and small opening ends is within 1.5mm, and the deformation of the inner diameter is smaller.
4. The mechanical vibration can promote the overflow of air holes in the liquid brazing filler metal, the density of the welding line is improved, and the performance of the joint is high.
5. Large-scale special equipment or devices are not needed, the welding process is flexible, the cost is low, and the engineering advantages are obvious.
Drawings
FIG. 1 is a schematic view of a welding fixture of the present invention;
FIG. 2 is a schematic representation of a 2A12 aluminum alloy skin of example 1;
FIG. 3 is a schematic view of a web with a carcass in accordance with example 1;
FIG. 4 is a schematic representation of the 2A12 aluminum alloy skin after scoring in example 1;
FIG. 5 is a horizontal external view of the aluminum alloy skin and the brazed workpiece with a ribbed skeleton structure obtained in example 1;
FIG. 6 is a vertical external view of the aluminum alloy skin obtained in example 1 together with a brazed workpiece having a ribbed skeletal structure;
fig. 7 is an appearance of a brazing seam between the aluminum alloy skin obtained in example 1 and a brazed workpiece having a ribbed skeleton structure.
Detailed Description
The technical solution of the present invention is not limited to the following specific embodiments, but includes any combination of the specific embodiments.
The first embodiment is as follows: the welding fixture in the embodiment is of a semicircular pipe structure and comprises a heat-insulating layer 1, a heating blanket 2, a limiting mould 3, a mould pull rod 4, a pressurizing gasket 5 and a pressurizing screw rod 6; a heating blanket 2 is attached to the inner surface of the heat-insulating layer 1, and the heating blanket 2 is covered on the outer surface of the limiting mould 3; a plurality of mould pull rods 4 are horizontally arranged on the upper edge of the limiting mould 3 at intervals in parallel, two pressurizing screws 6 are in threaded connection with the lower part of each mould pull rod 4, and the lower ends of the two pressurizing screws 6 are fixedly connected with a pressurizing gasket 5. Wherein the pressurizing gasket 5 is attached to a workpiece 7 to be welded on the limiting die 3.
The pressurizing screw 6 and the pressurizing gasket 5 of the embodiment are made of stainless steel, the pressurizing gasket 5 is directly placed on the surface of the workpiece 7 to be welded, the radian of the pressurizing gasket is consistent with that of the workpiece 7 to be welded, and tight fit is guaranteed. The limiting die 3 and the die pull rod 4 are made of aluminum alloy consistent with the workpiece 7 to be welded.
The second embodiment is as follows: the first difference between the present embodiment and the specific embodiment is: the heat-insulating layer is made of asbestos. The rest is the same as the first embodiment.
The third concrete implementation mode: in the embodiment, the method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure by using the welding fixture comprises the following steps:
firstly, performing pre-welding heat treatment on an aluminum alloy skin and a ribbed framework;
secondly, polishing and cleaning the aluminum alloy skin and the ribbed framework after heat treatment before welding;
marking a position to be welded on the aluminum alloy skin subjected to heat treatment;
fourthly, coating the brazing filler metal on the aluminum alloy skin and the ribbed framework respectively: placing the aluminum alloy skin on a heating table for heating, and coating brazing filler metal on the position to be welded determined in the third step after the preset temperature is reached; placing the ribbed framework on a heating table for heating, and coating brazing filler metal on the surface of the stud of the ribbed framework after the preset temperature is reached; in the brazing filler metal coating process, an ultrasonic electric soldering iron is used for applying vibration to the position where the brazing filler metal is coated, the frequency range of the ultrasonic electric soldering iron applying vibration is 15kHz-60kHz, and the output power range is 20W-500W;
fifthly, performing combined welding on the aluminum alloy skin and the ribbed framework: after cooling the aluminum alloy skin precoated with the brazing filler metal and the ribbed framework, accurately assembling the aluminum alloy skin and the ribbed framework to form a workpiece to be welded, then placing the workpiece into a limiting mould 3 of a welding fixture, wrapping a heating blanket 2 outside the limiting mould 3, arranging a heat insulation layer 1 outside the heating blanket 2, connecting a pressurizing screw 6 with a mould pull rod 4 in a threaded manner, and arranging a pressurizing gasket 5 between the pressurizing screw 4 and the workpiece to be welded; screwing the pressurizing screw 6 to apply pressure to the workpiece to be welded; heating the workpiece to be welded by using the heating blanket 2, preserving heat for 5-10min after the heating temperature reaches the preset welding temperature, and increasing the pressure of the pressurizing screw 6 on the workpiece to be welded; then, an electric hammer is adopted to apply impact vibration to the position of the pressurizing gasket 5, the impact frequency is 50-6000 times/min, and the impact power is 50-200W; and then stopping heating, keeping the pressure applied by the pressurizing screw 6 to the workpiece to be welded, cooling, and dismounting the welding fixture to finish welding.
The embodiment has the following beneficial effects:
1. the welding can be carried out in the atmospheric environment, the vacuum welding environment or gas protection is not needed, the size of the weldable component is large, and the shape limitation is not large.
2. The mechanical vibration can be assisted to rapidly break an oxide film which prevents the brazing filler metal and the base metal from being combined in a wetting mode, chemical brazing flux which is needed in the conventional brazing process is not needed, the welding speed is high, the efficiency is high, and the environmental pollution is avoided.
3. The mechanical vibration can improve the fluidity of the brazing filler metal and accelerate the fusion, thereby reducing the welding temperature. The welding temperature is reduced, so that the heat damage of the aluminum alloy base metal can be reduced, the deformation of the workpiece in the welding process is reduced, and the welding precision is high. In addition, the limiting die suitable for the curved-surface welding part is designed in the embodiment, so that the deformation of the workpiece can be further reduced. The 2A12 aluminum alloy skin and the ribbed web are brazed by the method of the embodiment, the appearance is regular after welding, the brazing seam is well formed, the deformation of the outer diameters of the large and small opening ends is within 1.5mm, and the deformation of the inner diameter is smaller.
4. The mechanical vibration can promote the overflow of air holes in the liquid brazing filler metal, the density of the welding line is improved, and the performance of the joint is high.
5. Large-scale special equipment or devices are not needed, the welding process is flexible, the cost is low, and the engineering advantages are obvious.
The fourth concrete implementation mode: the third difference between the present embodiment and the specific embodiment is that: and step two, polishing and cleaning before welding, namely polishing the aluminum alloy skin and the ribbed framework to be bright by using fine sand paper, and then performing ultrasonic cleaning by using acetone. The rest is the same as the third embodiment.
The fifth concrete implementation mode: this embodiment is different from the third or fourth embodiment in that: the preset temperature of the fourth step is 30 ℃ higher than the melting point of the brazing filler metal. The other is the same as the third or fourth embodiment.
The sixth specific implementation mode: the difference between this embodiment and one of the third to fifth embodiments is: the solder is Sn-based solder, Zn-based solder or Al-based solder. The rest is the same as one of the third to fifth embodiments.
The seventh embodiment: this embodiment differs from one of the third to sixth embodiments in that: in the fifth step, the heating rate is 8-15 ℃/min. The rest is the same as one of the third to sixth embodiments.
The specific implementation mode is eight: the present embodiment differs from one of the third to seventh embodiments in that: and the preset temperature in the fifth step is 5-10 ℃ higher than the solidus line of the brazing filler metal. The rest is the same as one of the third to seventh embodiments.
The specific implementation method nine: the eighth embodiment is different from the eighth embodiment in that: and in the step five, the time of single impact vibration is 2-10 s. The rest is the same as the embodiment eight.
The detailed implementation mode is ten: the present embodiment differs from the embodiment eight or nine in that: and the cooling mode in the fifth step is air cooling or air cooling. The others are the same as the embodiments eight or nine.
The effect of the invention is demonstrated by the following examples:
the first embodiment of the present invention provides a method for brazing a large-size aluminum alloy curved skin and a ribbed framework structure by using a welding fixture, which comprises the following steps:
brazing is carried out by adopting a welding fixture, the welding fixture is shown in figure 1, and the welding fixture comprises a heat-insulating layer 1, a heating blanket 2, a limiting die 3, a die pull rod 4, a pressurizing gasket 5 and a pressurizing screw rod 6; a heating blanket 2 is attached to the inner surface of the heat-insulating layer 1, and the heating blanket 2 is covered on the outer surface of the limiting mould 3; a plurality of die pull rods 4 are horizontally arranged on the upper edge of the limiting die 3 at intervals in parallel, two pressurizing screws 6 are connected below each die pull rod 4 in a threaded manner, and the lower ends of the two pressurizing screws 6 are fixedly connected with pressurizing gaskets 5; the pressurizing gasket 5 is attached to a workpiece 7 to be welded on the limiting die 3.
A workpiece 7 to be welded is placed on a limiting die 3 of a welding fixture, a heating blanket 2 is wrapped outside the limiting die 3, a heat insulation layer 1 is arranged outside the heating blanket 2, a pressurizing screw 6 is in threaded connection with a die pull rod 4, and a pressurizing gasket 5 is arranged between the pressurizing screw 6 and the workpiece to be welded; screwing the pressurizing screw 6 to apply pressure to the piece to be welded; heating the workpiece to be welded by using a heating blanket 2;
the 2A12 aluminum alloy skin and the web with certain taper are processed, and the structural schematic diagram is shown in figures 2 and 3. The length of the aluminum alloy skin is 770mm, the thickness is 2mm, the diameter of the large end is 482mm, and the diameter of the small end is 337 mm. The web plate of the ribbed framework has the following specifications: the length is 800mm, the radius of the inner surface of the large end is 216mm, and the radius of the outer surface of the small end is 242 mm; the radius of the inner surface of the small end is 141mm, the radius of the outer surface of the small end is 167mm, the web plate is provided with a ring rib structure, the height of each reinforcing rib is 25mm, the distance is 40mm, and the thickness is 5 mm.
1. Carrying out pre-welding heat treatment on the 2A12 aluminum alloy skin and the ribbed framework web plate, placing the test piece on a heating table, setting the temperature to 350 ℃, heating for 3 hours, taking the two materials off the heating table, and air cooling the two materials on a marble platform.
2. Polishing and cleaning the heat-treated 2A12 aluminum alloy skin and ribbed framework web before welding, slightly polishing the surfaces of all welding positions to be bright by using fine abrasive paper, cleaning the surfaces by using an ultrasonic cleaner filled with acetone solution, and cleaning oil stains and residues on the surfaces by using ultrasonic vibration.
3. According to the ring rib structure of the ribbed framework web plate, a vernier caliper is used for measuring, then lines are drawn on the 2A12 aluminum alloy skin to mark a welding position, and preparation is made for performing pre-coating treatment on the aluminum alloy skin. The scribed 2a12 aluminum alloy skin is shown in fig. 4.
4. The 2a12 aluminum alloy skin was pre-coated with braze. A rod-shaped Zn-5Al-1Cu brazing filler metal is selected, the diameter of the brazing filler metal rod is 5mm, and the melting point of the brazing filler metal rod is 380-400 ℃. First, a 2a12 aluminum alloy skin was fixed on a heating stage, set at a heating temperature of 420 ℃, and the workpiece was covered with a heat insulating material. And after the temperature reaches the set temperature, keeping heating, gradually removing the heat insulation material, coating the brazing filler metal rod on the surface to be welded, and simultaneously treating by adopting an ultrasonic electric iron. The working frequency of the ultrasonic electric iron is 60kHz, and the power is 100W. The braze coating thickness was 0.5 mm.
6. And (5) coating the framework of the web plate with the ribbed framework with the brazing filler metal according to the step 5.
7. And (3) accurately assembling the 2A12 aluminum alloy skin coated with the brazing filler metal and the ribbed framework web plate, and avoiding dislocation. After the assembly, the workpiece is placed into a limiting die 3 of a welding fixture, and a pressurizing screw 6 is screwed to apply pressure to a workpiece 7 to be welded. The temperature of the heating blanket 2 is set to 450 ℃ to uniformly heat the whole body, the heating rate is 10 ℃/min, and the heat loss of the heat-insulating layer 1 is reduced.
8. And (3) after the overall temperature of the workpiece 7 to be welded reaches 450 ℃, preserving the heat for 5min, and then adjusting the pressurizing screw 6 to pressurize the whole workpiece 7 to be welded at multiple points to keep the overall pressure uniform. And (3) sequentially applying impact vibration to the position of the pressurizing pad 5 by adopting an electric hammer, wherein the single impact time is 2s, the impact power is 100W, and the impact frequency is 400 Hz.
9. Keeping the pressure for 10min, stopping heating, removing the heat insulation layer 1, and air-cooling the whole workpiece 7 to be welded. After cooling, the welding fixture is detached to complete welding, and the high-penetration and high-strength aluminum alloy skin and the brazed workpiece with the ribbed framework structure are obtained, and the appearance diagrams are shown in fig. 5, 6 and 7. The welded workpiece has regular appearance, good brazing seam formation, less deformation of the outer diameter of the large and small opening ends within 1.5mm and less deformation of the inner diameter. The X-ray nondestructive inspection result shows that the penetration rate of the aluminum alloy skin and the ribbed framework is more than or equal to 80 percent. The mechanical vibration assisted brazing technology successfully realizes the welding of the 2A12 aluminum alloy skin and the ribbed framework structure.
Claims (9)
1. A brazing method for a large-size aluminum alloy curved surface skin and a ribbed framework structure is characterized by comprising the following steps:
firstly, performing pre-welding heat treatment on an aluminum alloy skin and a ribbed framework;
secondly, polishing and cleaning the aluminum alloy skin and the ribbed framework after heat treatment before welding;
marking a position to be welded on the aluminum alloy skin subjected to heat treatment;
fourthly, coating the brazing filler metal on the aluminum alloy skin and the ribbed framework respectively: placing the aluminum alloy skin on a heating table for heating, and coating brazing filler metal in the position to be welded determined in the third step after the preset temperature is reached; placing the ribbed framework on a heating table for heating, and coating brazing filler metal on the surface of the stud of the ribbed framework after the preset temperature is reached; in the brazing filler metal coating process, an ultrasonic electric soldering iron is used for applying vibration to the position where the brazing filler metal is coated, the frequency range of the ultrasonic electric soldering iron applying vibration is 15kHz-60kHz, and the output power range is 20W-500W;
fifthly, performing combined welding on the aluminum alloy skin and the ribbed framework: after cooling the aluminum alloy skin pre-coated with the brazing filler metal and the ribbed framework, assembling the aluminum alloy skin and the ribbed framework to form a workpiece to be welded, then placing the workpiece to be welded in a limiting die (3) of a welding fixture, wrapping a heating blanket (2) outside the limiting die (3), arranging a heat insulation layer (1) outside the heating blanket (2), connecting a pressurizing screw (6) with a die pull rod (4) in a threaded manner, and arranging a pressurizing gasket (5) between the pressurizing screw (4) and the workpiece to be welded; screwing a pressurizing screw (6) to apply pressure to the workpiece to be welded; heating the workpiece to be welded by using the heating blanket (2), preserving heat for 5-10min after the heating temperature reaches the preset welding temperature, and increasing the pressure of the pressurizing screw (6) on the workpiece to be welded; then, an electric hammer is adopted to apply impact vibration to the position of the pressurizing gasket (5), the impact frequency is 50-6000 times/min, and the impact power is 50-200W; then stopping heating, keeping the pressure applied by the pressurizing screw (6) on the workpiece to be welded, cooling, and dismounting the welding fixture to finish welding; the welding fixture is of a semicircular tube structure and comprises a heat insulation layer (1), a heating blanket (2), a limiting mould (3), a mould pull rod (4), a pressurizing gasket (5) and a pressurizing screw rod (6); a heating blanket (2) is attached to the inner surface of the heat-insulating layer (1), and the heating blanket (2) is coated on the outer surface of the limiting mould (3); a plurality of mould pull rods (4) are horizontally arranged on the upper edge of the limiting mould (3) at intervals in parallel, two pressurizing screws (6) are in threaded connection with the lower part of each mould pull rod (4), and the lower ends of the two pressurizing screws (6) are fixedly connected with a pressurizing gasket (5).
2. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein the insulating layer (1) is made of asbestos.
3. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein in the step two, polishing and cleaning before welding are carried out by polishing the aluminum alloy skin and the ribbed framework to be bright by using fine sand paper and then carrying out ultrasonic cleaning by using acetone.
4. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein the preset temperature in the fourth step is 30 ℃ higher than the melting point of the brazing filler metal.
5. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein the brazing filler metal is Sn-based brazing filler metal, Zn-based brazing filler metal or Al-based brazing filler metal.
6. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein in the fifth step, the heating rate is 8-15 ℃/min.
7. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein the preset temperature in the fifth step is 5-10 ℃ higher than the solidus line of the brazing filler metal.
8. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein the time of single impact vibration in the fifth step is 2-10 s.
9. The method for brazing the large-size aluminum alloy curved surface skin and the ribbed framework structure according to claim 1, wherein the cooling mode in the fifth step is air cooling or air cooling.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911261094.7A CN110899896B (en) | 2019-12-10 | 2019-12-10 | Welding fixture and method for brazing large-size aluminum alloy curved surface skin and ribbed framework structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911261094.7A CN110899896B (en) | 2019-12-10 | 2019-12-10 | Welding fixture and method for brazing large-size aluminum alloy curved surface skin and ribbed framework structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110899896A CN110899896A (en) | 2020-03-24 |
| CN110899896B true CN110899896B (en) | 2021-11-02 |
Family
ID=69824105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911261094.7A Active CN110899896B (en) | 2019-12-10 | 2019-12-10 | Welding fixture and method for brazing large-size aluminum alloy curved surface skin and ribbed framework structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110899896B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113644371B (en) * | 2021-08-19 | 2023-03-10 | 湖南汽车工程职业学院 | Manufacturing method of lightweight aluminum alloy battery bracket of new energy automobile |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2844550Y (en) * | 2005-11-16 | 2006-12-06 | 中信重型机械公司 | Copper-alloy bush of large grinder |
| CN1990149A (en) * | 2005-12-30 | 2007-07-04 | 航天材料及工艺研究所 | Welding method of titanium alloy framework and covering variable cross-section element |
| CN101284347A (en) * | 2008-05-28 | 2008-10-15 | 中国石油天然气第一建设公司 | Production method of special-shaped clamping fixture |
| CN201862888U (en) * | 2010-11-23 | 2011-06-15 | 福州阿石创光电子材料有限公司 | Heating system applied in brazing of target material |
| CN102784988A (en) * | 2012-08-31 | 2012-11-21 | 郑州机械研究所 | Method for vibration-assisted induction brazing |
| CN102974946A (en) * | 2012-11-12 | 2013-03-20 | 西安航空动力股份有限公司 | Method for controlling deformation of sheet bar honeycomb during vacuum soldering and brazing |
| CN103565287A (en) * | 2013-11-12 | 2014-02-12 | 哈尔滨工业大学 | Titanium pot with composite aluminum bottom and manufacturing method thereof |
| CN209115811U (en) * | 2018-10-06 | 2019-07-16 | 西南石油大学 | A kind of petroleum machinery pipeline fixing device |
-
2019
- 2019-12-10 CN CN201911261094.7A patent/CN110899896B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2844550Y (en) * | 2005-11-16 | 2006-12-06 | 中信重型机械公司 | Copper-alloy bush of large grinder |
| CN1990149A (en) * | 2005-12-30 | 2007-07-04 | 航天材料及工艺研究所 | Welding method of titanium alloy framework and covering variable cross-section element |
| CN101284347A (en) * | 2008-05-28 | 2008-10-15 | 中国石油天然气第一建设公司 | Production method of special-shaped clamping fixture |
| CN201862888U (en) * | 2010-11-23 | 2011-06-15 | 福州阿石创光电子材料有限公司 | Heating system applied in brazing of target material |
| CN102784988A (en) * | 2012-08-31 | 2012-11-21 | 郑州机械研究所 | Method for vibration-assisted induction brazing |
| CN102974946A (en) * | 2012-11-12 | 2013-03-20 | 西安航空动力股份有限公司 | Method for controlling deformation of sheet bar honeycomb during vacuum soldering and brazing |
| CN103565287A (en) * | 2013-11-12 | 2014-02-12 | 哈尔滨工业大学 | Titanium pot with composite aluminum bottom and manufacturing method thereof |
| CN209115811U (en) * | 2018-10-06 | 2019-07-16 | 西南石油大学 | A kind of petroleum machinery pipeline fixing device |
Non-Patent Citations (1)
| Title |
|---|
| Sn基钎料的Zn含量对纯铝超声钎焊接头组织和性能的影响;张永红，等.;《机械制造文摘(焊接分册)》;20191027(第5期);第23-28页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110899896A (en) | 2020-03-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103394783B (en) | Ultrasonic auxiliary vacuum brazing equipment | |
| CN103132071A (en) | Ultrasonic vibration coupling apparatus for laser restoration | |
| CN102240851A (en) | Welding forming method of thin invar alloy | |
| CN110899896B (en) | Welding fixture and method for brazing large-size aluminum alloy curved surface skin and ribbed framework structure | |
| CN102728937A (en) | Dissimilar metal welding method of titanium alloy and austenitic stainless steel | |
| CN106141490B (en) | A kind of method for welding for being brazed the solder and foamed aluminium and aluminium of foamed aluminium | |
| CN106041350A (en) | Tungsten/copper or tungsten/steel connector and method for preparing same | |
| CN108500411B (en) | Ultrasonic brazing device and method based on needle type welding head | |
| CN105251971B (en) | A kind of method hot rolling plate base process interlayer vacuum coating method | |
| CN101992331B (en) | Vacuum brazing process for super-Ni laminated material and Cr18-Ni8 stainless steel | |
| CN105965176B (en) | For soldering tungsten-copper alloy and the Ni base chilling solders and soldering processes of stainless steel | |
| CN105965121A (en) | Method for connecting magnesium alloy and aluminum alloy | |
| WO2018176628A1 (en) | Ultrasound flux-free aluminium pipe brazing method and apparatus | |
| CN101913022A (en) | Method for welding dissimilar materials of TA15 titanium alloy and chromium bronze through electron beams | |
| CN112518079B (en) | Fusion welding method for aluminum alloy porous micro-channel active cooling structure | |
| CN105269105A (en) | High-silicon aluminum alloy welding method for forming particle-reinforced weld joints through thermo-acoustic coupling | |
| CN105694614A (en) | Aluminum and steel plate for ships, method for welding aluminum and steel plate and method for preparing paint | |
| CN105290606A (en) | Friction stir welding method for foam aluminum material | |
| CN103084716B (en) | Pulse gas metal arc welding technology of titanium-aluminium micro laminated composite | |
| TWI836640B (en) | Joint body of stainless steel and copper and joint method of stainless steel and copper | |
| CN103464855B (en) | The large area carbide alloy method for welding of standing wave constraint | |
| CN103302414A (en) | Vacuum connecting method for stainless steel pieces | |
| CN103624393B (en) | The hot self-pressure method of attachment of rigid restraint | |
| CN101913023B (en) | Titanium alloy and tin bronze electron beam welding method | |
| CN210714788U (en) | Metal edge covering and machining tool for fan blade of aircraft engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20200326 Address after: 150001 Harbin, Nangang, West District, large straight street, No. 92 Applicant after: HARBIN INSTITUTE OF TECHNOLOGY Applicant after: BEIJING INSTITUTE OF ELECTRONIC SYSTEM ENGINEERING Address before: 150001 Harbin, Nangang, West District, large straight street, No. 92 Applicant before: HARBIN INSTITUTE OF TECHNOLOGY |
|
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |