A high-frequency ultrasonic-assisted forming method for copper-aluminum layered composite tubes

Abstract

The present invention provides a high-frequency ultrasonic assisted forming method for a copper-aluminum layered composite tube, which belongs to the technical field of non-ferrous metal preparation. The present invention aims at the problem that copper has excellent thermal and electrical conductivity but is expensive. The copper sleeve is assembled with an aluminum alloy rod, and then the aluminum alloy rod is extruded and deformed into a copper-clad aluminum strip-shaped slab. After multiple rolling passes, a copper / aluminum / copper sandwich structure layered thin plate is prepared, and then the copper / aluminum / copper sandwich structure is extended into a cylindrical part by high-frequency ultrasonic assisted stamping. The copper / aluminum / copper layered composite tube is formed by alternating high-frequency ultrasonic rolling and strong staggered spinning. The method has the advantages of saving raw materials, low cost, good forming performance, good copper / aluminum interface bonding, etc. The preparation method has advanced technology and is a very ideal method for preparing high-performance layered composite tubes.

Description

Technical Field

[0001] The invention belongs to the technical field of nonferrous metal preparation, and specifically discloses a high-frequency ultrasonic-assisted forming method for a copper-aluminum layered composite tube. Background Art

[0002] Copper / aluminum (Cu / Al) layered composite plates / tubes combine the excellent thermal and electrical conductivity of copper with the advantages of aluminum being lightweight, corrosion-resistant and inexpensive. In the process of power transmission, copper-aluminum layered transition joints replace the welding joints of aluminum and copper dissimilar metals. Copper-clad aluminum cables significantly reduce costs without reducing technical indicators. In terms of heat dissipation, copper / aluminum laminates utilize the excellent thermal conductivity of the copper surface and the high heat dissipation performance of the aluminum surface. The comprehensive heat dissipation performance is better than that of pure copper, and has been well applied in LED substrates, notebook computer radiators, and power battery connectors.

[0003] At present, the methods for preparing two or more component layered composite plates / tubes mainly include solid-solid rolling composite method (including flat roll rolling composite, corrugated roll rolling composite), explosive welding composite, diffusion composite, solid-liquid semi-molten state rolling composite and liquid-liquid bimetallic casting composite, etc. In the process of preparing layered composite plates / tubes, large-sized layered composite plates / tubes with excellent mechanical properties can be obtained by extrusion and rolling methods. Summary of the invention

[0004] The invention provides a high-frequency ultrasonic assisted forming method for a copper-aluminum layered composite tube. In view of the excellent thermal and electrical conductivity of copper and the advantages of aluminum being light and low in price, copper is used as an outer layer and aluminum is used as an inner layer to assemble into a cylindrical structure. A copper-clad aluminum sheet blank in the form of a strip is extruded through a designed concave mold cavity structure. A Cu / Al / Cu layered composite plate is prepared through a multi-pass rolling method. A layered tube blank for spinning is prepared through a high-frequency ultrasonic assisted stamping and stretching method. The preparation of high-quality Cu / Al / Cu layered composite spinning tubular parts is achieved through a strong staggered spinning method combined with a high-frequency ultrasonic vibration method.

[0005] The present invention provides a high-frequency ultrasonic assisted forming method for a copper-aluminum layered composite tube, comprising the following steps:

[0006] S1, Pretreatment of copper alloy cylinders and aluminum alloy rods

[0007] After the aluminum alloy rod is placed in liquid nitrogen for a preset time, it is placed on the upper part of the copper alloy cylinder, and the aluminum alloy rod is pressed into the copper alloy cylinder by a press machine, and the assembly form is an interference fit;

[0008] S2, preparation of copper-clad aluminum slabs

[0009] The assembled copper-aluminum bars are placed in a heating furnace, and the temperature is kept at 490±5℃ for 20 minutes. After the temperature is kept, the bars are taken out and placed in the extrusion sleeve of the extruder for hot extrusion. The extrusion sleeve temperature is 200±5℃, and the extrusion speed is 10mm / min. The bars are extruded into copper-clad aluminum slabs in the form of strips, and the slab thickness is 15mm.

[0010] S3, preparation of copper / aluminum / copper laminate

[0011] The copper-clad aluminum slab is subjected to multiple passes of hot rolling, the rolling reduction between each pass is less than 30%, and the next pass of rolling is performed after heating after each pass of rolling, the rolling speed is 2m / min, and the final rolled plate thickness is 2.0mm;

[0012] S4, preparation of copper / aluminum / copper layered composite tube blank

[0013] ① According to the size of the die annular positioning groove in the high-frequency ultrasonic assisted stamping and extension device, the copper / aluminum / copper layered composite plate is processed into a circular plate;

[0014] ② Place the circular copper / aluminum / copper layered composite plate in the annular positioning groove of the die, turn on the high-frequency ultrasonic generator, move the punch connected to the horn, and perform stamping and extension forming at a stamping speed of 1.0 mm / min to stamp into a cylinder with a diameter of 40 mm;

[0015] S5, preparation of copper / aluminum / copper layered composite tube

[0016] ① Place the copper / aluminum / copper layered composite tube blank on the mandrel of the high-frequency ultrasonic assisted spinning machine, make the spinning wheel and the ball connected to the horn contact the copper / aluminum / copper layered composite tube blank, turn on the mandrel and the high-frequency ultrasonic generator, the mandrel speed is 150r / min, and the copper / aluminum / copper layered composite tube blank is axially rolled by the ball with high-frequency ultrasonic vibration, the axial feed amount of the ball is 0.1mm, and the speed is 0.5m / min;

[0017] ② After high-frequency ultrasonic vibration rolling is completed, the first pass of strong staggered spinning is carried out. The three spinning wheels are distributed at 120°, and the longitudinal staggered distance between the spinning wheels is 2.0mm. The mandrel and the spinning wheels are turned on. The mandrel speed is 150r / min, the feed ratio is 1:1, and the thinning amount of a single pass is less than 20%;

[0018] ③ High-frequency ultrasonic vibration rolling and strong staggered spinning are carried out alternately, and the last pass is high-frequency ultrasonic vibration rolling.

[0019] In step S1, the inner surface of the copper alloy cylinder and the outer surface of the aluminum alloy rod are polished in advance with 400-mesh and 800-mesh sandpaper to remove surface impurities.

[0020] In step S4, the copper / aluminum / copper layered composite plate is processed into a circular plate by electrospark machining.

[0021] The above-mentioned high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube further includes step S6, mechanical processing

[0022] The copper-aluminum layered composite tube obtained by high-frequency ultrasonic assisted spinning is end-face processed by turning to a predetermined size.

[0023] In step S1, the press includes a first workbench, a first pillar, a first slide, a first upper support frame, a first hydraulic cylinder, a first ram, a first oil inlet pipe, a first oil return pipe, a first hydraulic oil tank, a first hydraulic pump and a first control cabinet; the first upper support frame is located above the first workbench; a plurality of first pillars pass through the first upper support frame and the first workbench to connect the first upper support frame and the first workbench into one; the first slide sliding sleeve is arranged on the plurality of first pillars and is located between the first upper support frame and the first workbench; the first hydraulic cylinder is installed on the top of the first upper support frame, the oil inlet is connected to the oil outlet of the first hydraulic pump through the first oil inlet pipe, the oil return port is connected to the first hydraulic oil tank through the first oil return pipe, and the piston passes through the first upper support frame and is connected to the first slide; the oil inlet of the first hydraulic pump is connected to the first hydraulic oil tank; the first ram is installed on the bottom surface of the first slide; and the first control cabinet controls the first hydraulic cylinder.

[0024] In step S2, the extruder includes a punch drive motor, a second box body, a punch support frame, a punch clamping mechanism, an extrusion punch, an extrusion sleeve, a sleeve support seat, an extrusion die, a clamping plate and a second control cabinet; the punch support frame is installed on the side wall of the second box body; the punch drive motor and the punch clamping mechanism are respectively installed on both sides of the punch support frame; the extrusion punch is installed on the punch clamping mechanism, and is driven by the punch drive motor to extend and retract laterally, and the outer diameter of the extrusion punch matches the outer diameter of the copper and aluminum bars; the sleeve support seat is installed in the second box body; the extrusion sleeve is laterally fixed on the sleeve support seat, including an outer sleeve, an inner sleeve and a resistance wire arranged between the outer sleeve and the inner sleeve; the inner sleeve includes a first sleeve section and a second sleeve section, and the first sleeve The inner diameter of the barrel section matches the outer diameter of the copper and aluminum rod, and the inner diameter of the second sleeve section matches the outer diameter of the extrusion die; the extrusion die is a hollow cylindrical structure, with a circular hole at the first end and a stepped rectangular hole at the second end. The inner diameter of the circular hole matches the outer diameter of the copper and aluminum rod, the extrusion die is inserted in the second sleeve section of the inner sleeve, the circular hole is flush with the first sleeve section of the inner sleeve, and the second end of the extrusion die is flush with the second end of the extrusion sleeve; the clamping plate is installed outside the second end of the extrusion sleeve to clamp the extrusion die; the second control cabinet controls the punch drive motor and the resistance wire; the copper and aluminum rod is placed in the extrusion sleeve, the extrusion punch applies pressure to the copper and aluminum rod, and the copper and aluminum rod is extruded from the stepped rectangular hole of the extrusion die to form a strip-shaped copper-clad aluminum sheet blank.

[0025] In step S4, the high-frequency ultrasonic assisted stamping and extension device includes a third upper support frame, a third workbench, a third pillar, a third upper slide, a third lower slide, a slide connecting rod, a third hydraulic cylinder, a third oil inlet pipe, a third oil return pipe, a third hydraulic oil tank, a third hydraulic pump, a third high-frequency ultrasonic generator, a third transducer, a third amplitude change rod, an amplitude change rod fixing seat, a stamping and extension punch, a lower support frame, a stamping and extension die and a third control cabinet; the third upper support frame is located above the third workbench; a plurality of third pillars pass through the third upper support frame and the third workbench to connect the third upper support frame and the third workbench into one; the third upper slide and the third lower slide are slidingly sleeved on a plurality of third pillars, and are connected to form a third slide through a plurality of slide connecting rods, and the third slide is located between the third upper support frame and the third workbench; the third hydraulic cylinder It is installed on the top of the third upper support frame, the oil inlet is connected to the oil outlet of the third hydraulic pump through the third oil inlet pipe, the oil return port is connected to the third hydraulic oil tank through the third oil return pipe, and the piston passes through the third upper support frame and is connected to the third upper slide; the oil inlet of the third hydraulic pump is connected to the third hydraulic oil tank; the amplitude rod fixing seat is installed on the third lower slide; the third amplitude rod passes through the amplitude rod fixing seat and the third lower slide, the top end is connected to the third transducer, and the bottom end is connected to the stamping and extension punch; the third high-frequency ultrasonic generator is connected to the third transducer through the third wire; the lower support frame is installed on the third workbench and is provided with a through hole; the stamping and extension die is installed in the through hole; the third control cabinet controls the third hydraulic cylinder and the third high-frequency ultrasonic generator; the circular copper / aluminum / copper layered composite plate is placed in the annular positioning groove of the stamping and extension die.

[0026] In step S5, the high-frequency ultrasonic assisted spinning machine includes a fourth box, a mandrel, a mandrel fixing mechanism, a mandrel drive motor, a fourth high-frequency ultrasonic generator, an axial track, a fourth transducer, a fourth amplitude rod, a ball, a tightening shaft, a fourth hydraulic cylinder, a fourth hydraulic pump, a fourth hydraulic oil tank, a first rotating wheel, a second rotating wheel, a third rotating wheel and a fourth control cabinet; the mandrel fixing mechanism is installed in the fourth box; the mandrel drive motor is installed outside the fourth box; the mandrel is transversely arranged in the fourth box, and the input end is connected to the mandrel drive motor through the mandrel fixing mechanism, and is driven to rotate by the mandrel drive motor; the tightening shaft is transversely arranged in the fourth box, at the same height as the mandrel, and the input end passes through the fourth box and is connected to the fourth hydraulic cylinder, and is driven to extend and retract transversely by the fourth hydraulic cylinder; the oil inlet of the fourth hydraulic cylinder is connected to the oil outlet of the fourth hydraulic pump through the fourth oil inlet pipe, and the oil return port is connected to the oil outlet of the fourth hydraulic pump through the fourth oil return pipe. The pipe is connected to the fourth hydraulic oil tank; the oil inlet of the fourth hydraulic pump is connected to the fourth hydraulic oil tank; the first rotary wheel, the second rotary wheel and the third rotary wheel are all rotatably installed in the fourth box body, and can all move axially along the core shaft, the first rotary wheel and the second rotary wheel are located below the core shaft, and the third rotary wheel is located above the core shaft; the axial track is installed in the fourth box body; the fourth transducer is slidably installed on the axial track; the bottom end of the fourth amplitude transformer is connected to the fourth transducer, and the top end is connected to the ball; the fourth high-frequency ultrasonic generator is connected to the fourth transducer and the fourth control cabinet through the fourth wire; the fourth control cabinet controls the core shaft drive motor, the fourth hydraulic cylinder, the first rotary wheel, the second rotary wheel and the third rotary wheel through the fourth control line; the copper / aluminum / copper layered composite tube blank is sleeved on the output end of the core shaft, and is tightened by the output end of the tightening shaft, and the outer wall is in contact with the first rotary wheel, the second rotary wheel, the third rotary wheel and the ball.

[0027] The present invention has the following beneficial effects.

[0028] The present invention aims at the problem that copper has excellent thermal and electrical conductivity, but is expensive. The copper sleeve is assembled with an aluminum alloy rod, which is deformed into a copper-clad aluminum strip-shaped slab through extrusion and plastic deformation. A copper / aluminum / copper sandwich structure layered sheet is prepared through multiple rolling passes, and a cylindrical piece is extended through high-frequency ultrasonic assisted stamping. The copper / aluminum / copper layered composite tube is formed by alternating high-frequency ultrasonic rolling and strong staggered spinning. The method has the advantages of saving raw materials, low cost, good forming performance, and good copper / aluminum interface bonding. The preparation method is advanced in technology and is a very ideal method for preparing high-performance layered composite tubes. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 Schematic diagram of press fitting of aluminum alloy rod and copper alloy cylinder;

[0031] Figure 2 It is a schematic diagram of the extrusion molding of copper-clad aluminum sheet blank;

[0032] Figure 3 It is a cross-sectional view of the extrusion die along the length direction of the stepped rectangular hole;

[0033] Figure 4 It is a cross-sectional view of the extrusion die along the width direction of the stepped rectangular hole;

[0034] Figure 5 is a schematic diagram of the second end of the extrusion die;

[0035] Figure 6 Schematic diagram of stamping and stretch forming of a circular copper / aluminum / copper laminate;

[0036] Figure 7 Schematic diagram of the spinning process for a copper / aluminum / copper layered composite tube blank;

[0037] Figure 8 This is the microscopic morphology of the copper-aluminum interface.

[0038] The list of reference numerals is as follows:

[0039] 1-aluminum alloy rod, 2-copper alloy tube, 3-copper aluminum rod, 4-copper clad aluminum plate, 5-round copper / aluminum / copper layered composite plate, 6-copper / aluminum / copper layered composite tube;

[0040] 101-first workbench, 102-first pillar, 103-first slide, 104-first upper support frame, 105-first hydraulic cylinder, 106-first pressure head, 107-first oil inlet pipe, 108-first oil return pipe, 109-first control cabinet, 110-first display screen, 111-upper stroke controller indicator light, 112-lower stroke controller indicator light, 113-pressure controller indicator light, 114-first power switch indicator light, 115-first power switch, 116-pressure controller, 117-lower stroke controller, 118-upper stroke controller, 119-first control line a, 120-first hydraulic oil tank, 121-first pressure gauge a, 122-first pressure gauge b, 123-first control line b;

[0041] 201-punch driving motor, 202-punch supporting frame, 203-second box body, 204-punch clamping mechanism, 205-extrusion punch, 206-outer sleeve, 207-resistance wire, 208-inner sleeve, 209-extrusion die, 210-pressing plate, 211-sleeve supporting seat, 212-second base, 213-second power switch, 214-temperature controller, 215-extrusion punch forward controller, 216-extrusion punch return controller, 217-extrusion punch return controller indicator light, 218-extrusion punch forward controller indicator light, 219-temperature controller indicator light, 220-second power switch indicator light, 221-second display screen, 222-second control cabinet;

[0042] 301-third hydraulic cylinder, 302-third upper support frame, 303-third pillar, 304-third upper slide, 305-junction box, 306-third transducer, 307-upper amplitude rod, 308-slide connecting rod, 309-middle amplitude rod, 310-amplitude rod fixing seat, 311-third lower slide, 312-lower amplitude rod, 313-stamping extension punch, 314-third wire b, 315-stamping extension die, 316-lower support frame, 317-third workbench, 318-third high-frequency ultrasonic generator, 319-third control line a, 320-third pressure gauge a, 321-third pressure gauge b, 322-third hydraulic oil tank, 323-third control line b, 324-amplitude controller, 325-amplitude controller Controller indicator light, 326-frequency controller, 327-frequency controller indicator light, 328-power controller, 329-power controller indicator light, 330-high-frequency ultrasonic generator controller, 331-high-frequency ultrasonic generator controller indicator light, 332-third display screen b, 333-pressure controller, 334-upper stroke controller, 335-lower stroke controller, 336-third power switch, 337-third power switch indicator light, 338-lower stroke controller indicator light, 339-upper stroke controller indicator light, 340-pressure controller indicator light, 341-third display screen a, 342-third control cabinet, 343-third oil inlet pipe, 344-third oil return pipe, 345-protective cover, 346-third wire a;

[0043] 401-fourth box, 402-mandrel, 403-mandrel fixing mechanism, 404-mandrel driving motor, 405-fourth high-frequency ultrasonic generator, 406-fourth base, 407-fourth wire, 408-axial track, 409-fourth transducer, 410-fourth amplitude change rod, 411-second retaining ring, 412-second rotating wheel, 413-second supporting frame, 414-first retaining ring, 415-first rotating wheel, 416-first supporting frame, 417-tightening shaft, 418-fourth control line, 419-fourth hydraulic cylinder, 420-power controller, 421-fourth hydraulic cylinder, 422-fourth hydraulic cylinder, 423-fourth hydraulic cylinder, 424-fourth hydraulic cylinder, 425-fourth hydraulic cylinder, 426-fourth hydraulic cylinder, 427-fourth hydraulic cylinder, 428-fourth hydraulic cylinder, 429-fourth hydraulic cylinder, 430-fourth hydraulic cylinder, 431-fourth hydraulic cylinder, 432-fourth hydraulic cylinder, 433-fourth hydraulic cylinder, 434-fourth hydraulic cylinder, 435-fourth hydraulic cylinder, 436-fourth hydraulic cylinder, 437-fourth hydraulic cylinder, 438-fourth hydraulic cylinder, 439-fourth hydraulic cylinder, 440-fourth hydraulic cylinder, 441-fourth hydraulic cylinder, 442-fourth hydraulic cylinder, 443-fourth hydraulic cylinder, 444-fourth hydraulic cylinder, 445-fourth hydraulic cylinder, 446-fourth hydraulic cylinder, 447-fourth hydraulic cylinder, 448-fourth hydraulic cylinder, 449-fourth hydraulic cylinder, 450-fourth hydraulic cylinder, 451-fourth hydraulic cylinder, 452-four 1-frequency controller, 422-high-frequency ultrasonic generator controller, 423-stroke controller, 424-speed controller controller, 425-fourth power switch, 426-fourth power switch indicator light, 427-speed controller indicator light, 428-stroke controller indicator light, 429-high-frequency ultrasonic generator controller indicator light, 430-fourth display screen, 431-frequency controller indicator light, 432-power controller indicator light, 433-fourth control cabinet, 434-third support frame, 435-third rotating wheel, 436-third retaining ring, 437-ball. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. 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.

[0045] The present embodiment provides a high-frequency ultrasonic assisted forming method for a copper-aluminum layered composite tube, using copper as the outer layer and aluminum as the inner layer, and by designing the extrusion die cavity structure, a Cu / Al / Cu rolled slab is prepared by hot extrusion, and the rolled slab is subjected to multiple hot rollings to obtain a Cu / Al / Cu layered composite plate, which is punched and stretched into a Cu / Al / Cu layered composite tube blank by a high-frequency ultrasonic assisted method, and a Cu / Al / Cu layered composite tube is prepared by an ultrasonic assisted strong staggered spinning method. The Cu / Al / Cu layered composite tube prepared by this method has excellent forming performance, good mechanical properties, high material utilization, reduced cost, and metallurgical bonding is achieved between the Cu-Al interface.

[0046] The chemical materials used in the present invention are: copper alloy tube, aluminum alloy rod, sandpaper, and the combined preparation amount is as follows: the measurement units are piece, millimeter, milliliter, liter, and sheet.

[0047]

[0048] The above method comprises the following steps.

[0049] S1, Pretreatment of copper alloy cylinders and aluminum alloy rods

[0050] ① Use 400-mesh and 800-mesh sandpaper to grind the inner surface of the copper alloy cylinder 2 and the outer surface of the aluminum alloy rod 1 to remove oil, rust and impurities on the surface;

[0051] ② After the aluminum alloy rod 1 is placed in liquid nitrogen for 30 minutes, it is placed on the upper part of the copper alloy cylinder 2, and the aluminum alloy rod 1 is pressed into the copper alloy cylinder 2 by a press machine. The assembly form is an interference fit.

[0052] S2, preparation of copper-clad aluminum slabs

[0053] The assembled copper-aluminum rod 3 is placed in a heating furnace, and the insulation temperature is 490±5℃ for 20 minutes. After insulation, it is taken out and placed in the extrusion sleeve of the extruder for hot extrusion. The extrusion sleeve temperature is 200±5℃, the extrusion speed is 10mm / min, and it is extruded into a copper-clad aluminum slab 4 in the form of a strip, and the slab thickness is 15mm.

[0054] S3, preparation of copper / aluminum / copper laminate

[0055] The copper-clad aluminum slab 4 is subjected to multiple passes of hot rolling, with the rolling reduction between single passes being less than 30%. After a single rolling pass, it is heated before the next rolling pass. The rolling speed is 2m / min, and the final rolled plate thickness is 2.0mm.

[0056] S4, preparation of copper / aluminum / copper layered composite tube blank

[0057] ① According to the size of the die annular positioning groove in the high-frequency ultrasonic-assisted stamping and extension device, the copper / aluminum / copper layered composite plate is processed into a circular plate with a diameter of 80 mm by electric spark wire cutting;

[0058] ② Place the circular copper / aluminum / copper layered composite plate 5 in the annular positioning groove of the die 315, turn on the high-frequency ultrasonic generator 318, move the punch 313 connected to the horn, and perform stamping and stretching forming at a stamping speed of 1.0 mm / min. Punch it into a cylinder with a diameter of 40 mm for use in strong offset spinning.

[0059] S5, preparation of copper / aluminum / copper layered composite tube

[0060] ① Place the copper / aluminum / copper layered composite tube 6 on the mandrel 402 of the high-frequency ultrasonic assisted spinning machine, make the rotating wheel and the ball 437 connected to the horn contact the copper / aluminum / copper layered composite tube 6, turn on the mandrel 402 and the high-frequency ultrasonic generator 405, the mandrel speed is 150r / min, and the copper / aluminum / copper layered composite tube 6 is axially high-frequency ultrasonic vibration rolled by the ball 437, the axial feed amount of the ball 437 is 0.1mm, and the speed is 0.5m / min;

[0061] ② After high-frequency ultrasonic vibration rolling is completed, the first pass of strong staggered spinning is carried out. The three spinning wheels are distributed at 120°, and the longitudinal staggered distance between the spinning wheels is 2.0mm. The mandrel and the spinning wheels are turned on. The mandrel speed is 150r / min, the feed ratio is 1:1, and the thinning amount of a single pass is less than 20%;

[0062] ③ High-frequency ultrasonic vibration rolling and strong staggered spinning are carried out alternately, and the last pass is high-frequency ultrasonic vibration rolling to improve the surface quality of the formed part and reduce the surface roughness value.

[0063] S6, machining

[0064] The copper-aluminum layered composite tube obtained by high-frequency ultrasonic assisted spinning is end-face processed by turning to a predetermined size.

[0065] S7, Storage

[0066] The prepared copper / aluminum / copper layered composite tube is packed with soft materials and stored in a clean and dry environment. It should be protected from moisture, sunlight, acid, alkali and salt corrosion. The storage temperature is 20°C and the relative humidity is ≤10%.

[0067] like Figure 8 As shown, a copper-aluminum suited cylindrical rod billet method is adopted, and a copper / aluminum / copper layered composite strip billet of copper-clad aluminum is formed by heating and extrusion, and a layered thin plate of a copper / aluminum / copper sandwich structure is formed by rolling, and high-frequency ultrasonic assisted stamping is used to extend it into a strong staggered spinning cylindrical tube billet. During the strong staggered spinning process, high-frequency ultrasonic rolling is applied alternately to reduce the deformation resistance during the spinning process, improve the interfacial bonding strength of the copper-aluminum interface, promote the diffusion of elements on the interface, achieve metallurgical bonding between the interfaces, improve the surface quality of the spun tube, and avoid copper and aluminum stratification and surface wrinkles and peeling defects during the spinning process.

[0068] The press includes a first workbench 101 , a first support column 102 , a first slide 103 , a first upper support frame 104 , a first hydraulic cylinder 105 , a first pressing head 106 , a first oil inlet pipe 107 , a first oil return pipe 108 , a first hydraulic oil tank 120 , a first hydraulic pump and a first control cabinet 109 .

[0069] The first upper support frame 104 is located above the first workbench 101; multiple first pillars 102 pass through the first upper support frame 104 and the first workbench 101 to connect the first upper support frame 104 and the first workbench 101 into one; the first slide 103 is slidably mounted on the multiple first pillars 102 and is located between the first upper support frame 104 and the first workbench 101; the first hydraulic cylinder 105 is installed on the top of the first upper support frame 104, the oil inlet is connected to the oil outlet of the first hydraulic pump through the first oil inlet pipe 107, the oil return port is connected to the first hydraulic oil tank 120 through the first oil return pipe 108, the piston passes through the first upper support frame 104 and is connected to the first slide 103; the oil inlet of the first hydraulic pump is connected to the first hydraulic oil tank 120; the first pressure head 106 is installed on the bottom surface of the first slide 103; the first control cabinet 109 controls the first hydraulic cylinder 105 through the first control line a119 and the first control line b123.

[0070] The first control cabinet 109 is provided with a first display screen 110, an upper stroke controller indicator light 111, a lower stroke controller indicator light 112, a pressure controller indicator light 113, a first power switch indicator light 114, a first power switch 115, a pressure controller 116, a lower stroke controller 117, and an upper stroke controller 118.

[0071] A first pressure gauge a121 and a first pressure gauge b122 are installed on the first hydraulic oil tank 120 .

[0072] The extruder includes a punch driving motor 201 , a second housing 203 , a punch support frame 202 , a punch clamping mechanism 204 , an extrusion punch 205 , an extrusion sleeve, a sleeve support seat 211 , an extrusion die 209 , a clamping plate 210 and a second control cabinet 222 .

[0073] The punch support frame 202 is installed on the side wall of the second box body 203; the punch drive motor 201 and the punch clamping mechanism 204 are respectively installed on both sides of the punch support frame 202; the extrusion punch 205 is installed on the punch clamping mechanism 204, and is driven by the punch drive motor 201 to extend and retract horizontally, and the outer diameter of the extrusion punch 205 matches the outer diameter of the copper-aluminum rod 3; the sleeve support seat 211 is installed in the second box body 203; the extrusion sleeve is laterally fixed on the sleeve support seat 211, including an outer sleeve 206, an inner sleeve 208 and a resistance wire 207 arranged between the outer sleeve 206 and the inner sleeve 208; the inner sleeve 208 includes a first sleeve section and a second sleeve section, the inner diameter of the first sleeve section matches the outer diameter of the copper-aluminum rod 3, and the inner diameter of the second sleeve section matches the outer diameter of the extrusion die 209. The extrusion die 209 is a hollow cylindrical structure, with a circular hole at the first end and a stepped rectangular hole at the second end. The transition between the circular hole and the stepped rectangular hole is smooth, and the inner diameter of the circular hole matches the outer diameter of the copper-aluminum rod 3. The extrusion die 209 is inserted in the second sleeve section of the inner sleeve 208, and the circular hole is flush with the first sleeve section of the inner sleeve 208. The second end of the extrusion die 209 is flush with the second end of the extrusion sleeve; the clamping plate 210 is installed outside the second end of the extrusion sleeve to clamp the extrusion die 209; the second control cabinet 222 controls the punch drive motor 201 and the resistance wire 207; the copper-aluminum rod 3 is placed in the extrusion sleeve, and the extrusion punch 205 applies pressure to the copper-aluminum rod 3 to extrude the copper-aluminum rod 3 from the stepped rectangular hole of the extrusion die 209 to form a strip-shaped copper-clad aluminum sheet blank 4.

[0074] The second control cabinet 222 and the second box body 203 are both installed on the second base 212 .

[0075] The second control cabinet 222 is provided with a second power switch 213, a temperature controller 214, an extrusion punch forward controller 215, an extrusion punch return controller 216, an extrusion punch return controller indicator light 217, an extrusion punch forward controller indicator light 218, a temperature controller indicator light 219, a second power switch indicator light 220, and a second display screen 221; the punch drive motor 201 and the resistance wire 207 are connected to the second control cabinet 222 via the control line inside the second base 212.

[0076] The high-frequency ultrasonic assisted stamping and extension device includes a third upper support frame 302, a third workbench 317, a third pillar 303, a third upper slide 304, a third lower slide 311, a slide connecting rod 308, a third hydraulic cylinder 301, a third oil inlet pipe 343, a third oil return pipe 344, a third hydraulic oil tank 322, a third hydraulic pump, a third high-frequency ultrasonic generator 318, a third transducer 306, a third amplitude transformer, an amplitude transformer fixing seat 310, a stamping and extension punch 313, a lower support frame 316, a stamping and extension die 315 and a third control cabinet 342.

[0077] The third upper support frame 302 is located above the third workbench 317; multiple third pillars 303 pass through the third upper support frame 302 and the third workbench 317 to connect the third upper support frame 302 and the third workbench 317 into one; the third upper slide 304 and the third lower slide 311 are slidably mounted on the multiple third pillars 303, and are connected to form a third slide through multiple slide connecting rods 308, and the third slide is located between the third upper support frame 302 and the third workbench 317; the third hydraulic cylinder 301 is installed on the top of the third upper support frame 302, the oil inlet is connected to the oil outlet of the third hydraulic pump through the third oil inlet pipe 343, the oil return port is connected to the third hydraulic oil tank 322 through the third oil return pipe 344, and the piston passes through the third upper support frame 302 and is connected to the third upper slide 304; the inlet of the third hydraulic pump The oil port is connected to the third hydraulic oil tank 322; the amplitude rod fixing seat 310 is installed on the third lower slide frame 311 by fastening bolts; the third amplitude rod passes through the amplitude rod fixing seat 310 and the third lower slide frame 311, the top end is connected to the third transducer 306, and the bottom end is connected to the stamping extension punch 313 serving as an ultrasonic tool head; the third high-frequency ultrasonic generator 318 is connected to the third transducer 306 through a third wire; the lower support frame 316 is installed on the third workbench 317 and is provided with a through hole; the stamping extension die 315 is installed in the through hole; the third control cabinet 342 controls the third hydraulic cylinder 301 and the third high-frequency ultrasonic generator 318 through the third control line a319 and the third control line b323; the circular copper / aluminum / copper layered composite plate 5 is placed in the annular positioning groove of the stamping extension die 315.

[0078] The third amplitude transformer includes an upper amplitude transformer 307, a middle amplitude transformer 309 and a lower amplitude transformer 312 which are arranged in sequence from upper to lower. A protective cover 345 is installed outside the upper amplitude transformer 307 and the third transducer 306. A junction box 305 is installed on the protective cover 345. The third transducer 306 and the junction box 305 are connected via a third wire a346. The junction box 305 and the third high-frequency ultrasonic generator 318 are connected via a third wire b314.

[0079] The third hydraulic oil tank 322 is installed with a third pressure gauge a320 and a third pressure gauge b321.

[0080] The third control cabinet 342 is provided with a third display screen a341, a pressure controller indicator light 340, an upper stroke controller indicator light 339, a lower stroke controller indicator light 338, a third power switch indicator light 337, a third power switch 336, a lower stroke controller 335, an upper stroke controller 334, a pressure controller 333, a third display screen b332, a high-frequency ultrasonic generator controller indicator light 331, a high-frequency ultrasonic generator controller 330, a power controller indicator light 329, a power controller 328, a frequency controller indicator light 327, a frequency controller 326, an amplitude controller indicator light 345, and an amplitude controller 324.

[0081] The high-frequency ultrasonic assisted spinning machine includes a fourth box body 401, a core shaft 402, a core shaft fixing mechanism 403, a core shaft driving motor 404, a fourth high-frequency ultrasonic generator 405, an axial track 408, a fourth transducer 409, a fourth amplitude rod 410, a ball 437, a tightening shaft 417, a fourth hydraulic cylinder 419, a fourth hydraulic pump, a fourth hydraulic oil tank, a first rotating wheel 415, a second rotating wheel 412, a third rotating wheel 435 and a fourth control cabinet 433.

[0082] The spindle fixing mechanism 403 is installed in the fourth box body 401; the spindle driving motor 404 is installed outside the fourth box body 401; the spindle 402 is arranged horizontally in the fourth box body 401, and the input end is connected to the spindle driving motor 404 through the spindle fixing mechanism 403, and is driven to rotate by the spindle driving motor 404; the tightening shaft 417 is arranged horizontally in the fourth box body 401, and is at the same height as the spindle 402. The input end passes through the fourth box body 401 and is connected to the fourth hydraulic cylinder 419, and is driven to extend and retract horizontally by the fourth hydraulic cylinder 419; the oil inlet of the fourth hydraulic cylinder 419 is connected to the oil outlet of the fourth hydraulic pump through the fourth oil inlet pipe, and the oil return port is connected to the fourth hydraulic oil tank through the fourth oil return pipe; the oil inlet of the fourth hydraulic pump is connected to the fourth hydraulic oil tank; the first rotating wheel 415, the second rotating wheel 412, and the third rotating wheel 435 are all rotatably installed in the fourth box body 401, and can all be moved axially along the spindle 402. The first rotating wheel 41 5. The second rotating wheel 412 is located below the mandrel 402, and the third rotating wheel 435 is located above the mandrel 402; the axial track 408 is installed in the fourth box body 401; the fourth transducer 409 is slidably installed on the axial track 408; the bottom end of the fourth amplitude rod 410 is connected to the fourth transducer 409, and the top end is connected to the ball 437 as an ultrasonic tool head; the fourth high-frequency ultrasonic generator 405 is connected to the fourth transducer 409 and the fourth control cabinet 433 through the fourth wire 407; the fourth control cabinet 433 controls the mandrel drive motor 404, the fourth hydraulic cylinder 419, the first rotating wheel 415, the second rotating wheel 412, and the third rotating wheel 435 through the fourth control line 418; the copper / aluminum / copper layered composite tube blank 6 is sleeved on the output end of the mandrel 402, and is tightened by the output end of the tightening shaft 417, and the outer wall is in contact with the first rotating wheel 415, the second rotating wheel 412, the third rotating wheel 435 and the ball 437.

[0083] The installation method of the rotating wheel is as follows: the first support frame 416, the second support frame 413 and the third support frame 434 are installed in the fourth box body 401, and the first support frame 416, the second support frame 413 and the third support frame 434 can all move axially along the core shaft 402; the first rotating wheel 415 is rotatably installed on the first support frame 416, and its axial movement on the first support frame 416 is limited by the first retaining ring 414; the second rotating wheel 412 is rotatably installed on the second support frame 413, and its axial movement on the second support frame 413 is limited by the second retaining ring 411; the third rotating wheel 435 is rotatably installed on the third support frame 434, and its axial movement on the third support frame 434 is limited by the third retaining ring 436.

[0084] The fourth control cabinet 433 is equipped with a power controller indicator light 432, a frequency controller indicator light 431, a fourth display screen 430, a high-frequency ultrasonic generator controller indicator light 429, a stroke controller indicator light 428, a speed controller indicator light 427, a fourth power switch indicator light 426, a fourth power switch 425, a speed controller controller 424, a stroke controller 423, a high-frequency ultrasonic generator controller 422, a frequency controller 421, and a power controller 420.

[0085] The fourth box 401 , the fourth high-frequency ultrasonic generator 405 , and the fourth control cabinet 433 are all installed on the fourth base 406 .

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-frequency ultrasonic-assisted forming method for a copper-aluminum layered composite tube. It is characterized in that The method comprises the following steps: S1, Pretreatment of copper alloy cylinders and aluminum alloy rods After the aluminum alloy rod is placed in liquid nitrogen for a preset time, it is placed on the upper part of the copper alloy cylinder, and the aluminum alloy rod is pressed into the copper alloy cylinder by a press machine, and the assembly form is an interference fit; S2, preparation of copper-clad aluminum slabs The assembled copper-aluminum bars are placed in a heating furnace, and the temperature is kept at 490±5℃ for 20 minutes. After the temperature is kept, the bars are taken out and placed in the extrusion sleeve of the extruder for hot extrusion. The extrusion sleeve temperature is 200±5℃, and the extrusion speed is 10mm / min. The bars are extruded into copper-clad aluminum slabs in the form of strips, and the slab thickness is 15mm. S3, preparation of copper / aluminum / copper laminate The copper-clad aluminum slab is subjected to multiple passes of hot rolling, the rolling reduction between each pass is less than 30%, and the next pass of rolling is performed after heating after each pass of rolling, the rolling speed is 2m / min, and the final rolled plate thickness is 2.0mm; S4, preparation of copper / aluminum / copper layered composite tube blank ① According to the size of the die annular positioning groove in the high-frequency ultrasonic assisted stamping and extension device, the copper / aluminum / copper layered composite plate is processed into a circular plate; ② Place the circular copper / aluminum / copper layered composite plate in the annular positioning groove of the die, turn on the high-frequency ultrasonic generator, move the punch connected to the horn, and perform stamping and extension forming at a stamping speed of 1.0 mm / min to stamp into a cylinder with a diameter of 40 mm; S5, preparation of copper / aluminum / copper layered composite tube ① Place the copper / aluminum / copper layered composite tube blank on the mandrel of the high-frequency ultrasonic assisted spinning machine, make the spinning wheel and the ball connected to the horn contact the copper / aluminum / copper layered composite tube blank, turn on the mandrel and the high-frequency ultrasonic generator, the mandrel speed is 150r / min, and the copper / aluminum / copper layered composite tube blank is axially rolled by the ball with high-frequency ultrasonic vibration, the axial feed amount of the ball is 0.1mm, and the speed is 0.5m / min; ② After high-frequency ultrasonic vibration rolling is completed, the first pass of strong staggered spinning is carried out. The three spinning wheels are distributed at 120°, and the longitudinal staggered distance between the spinning wheels is 2.0mm. The mandrel and the spinning wheels are turned on. The mandrel speed is 150r / min, the feed ratio is 1:1, and the thinning amount of a single pass is less than 20%; ③ High-frequency ultrasonic vibration rolling and strong staggered spinning are carried out alternately, and the last pass is high-frequency ultrasonic vibration rolling.

2. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 1, It is characterized in that In step S1, the inner surface of the copper alloy cylinder and the outer surface of the aluminum alloy rod are polished in advance with 400-mesh and 800-mesh sandpaper to remove surface impurities.

3. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 2, It is characterized in that In step S4, the copper / aluminum / copper layered composite plate is processed into a circular plate by electrospark machining.

4. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 3, It is characterized in that Also includes step S6, mechanical processing The copper-aluminum layered composite tube obtained by high-frequency ultrasonic assisted spinning is end-face processed by turning to a predetermined size.

5. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 1, It is characterized in that In step S1, the press includes a first workbench, a first support, a first slide, a first upper support frame, a first hydraulic cylinder, a first pressure head, a first oil inlet pipe, a first oil return pipe, a first hydraulic oil tank, a first hydraulic pump and a first control cabinet; The first upper support frame is located above the first workbench; A plurality of first pillars pass through the first upper support frame and the first workbench to connect the first upper support frame and the first workbench into one; The first slide is slidably sleeved on the plurality of first pillars and is located between the first upper support frame and the first workbench; The first hydraulic cylinder is installed on the top of the first upper support frame, the oil inlet is connected to the oil outlet of the first hydraulic pump through the first oil inlet pipe, the oil return port is connected to the first hydraulic oil tank through the first oil return pipe, and the piston passes through the first upper support frame and is connected to the first slide frame; The oil inlet of the first hydraulic pump is connected to the first hydraulic oil tank; The first pressing head is mounted on the bottom surface of the first sliding frame; The first control cabinet controls the first hydraulic cylinder.

6. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 1, It is characterized in that In step S2, the extruder includes a punch drive motor, a second housing, a punch support frame, a punch clamping mechanism, an extrusion punch, an extrusion sleeve, a sleeve support seat, an extrusion die, a clamping plate, and a second control cabinet; The punch support frame is installed on the side wall of the second box body; The punch driving motor and the punch clamping mechanism are respectively installed on both sides of the punch supporting frame; The extrusion punch is installed on the punch clamping mechanism and is driven by the punch driving motor to extend and retract horizontally. The outer diameter of the extrusion punch matches the outer diameter of the copper and aluminum bars. The sleeve support seat is installed in the second box body; The extrusion sleeve is transversely fixed on the sleeve support seat, and comprises an outer sleeve, an inner sleeve and a resistance wire arranged between the outer sleeve and the inner sleeve; The inner sleeve comprises a first sleeve section and a second sleeve section, the inner diameter of the first sleeve section matches the outer diameter of the copper-aluminum bar, and the inner diameter of the second sleeve section matches the outer diameter of the extrusion die; The extrusion die is a hollow cylindrical structure, with a circular hole at the first end and a stepped rectangular hole at the second end. The inner diameter of the circular hole matches the outer diameter of the copper and aluminum bars. The extrusion die is inserted into the second sleeve section of the inner sleeve, the circular hole is flush with the first sleeve section of the inner sleeve, and the second end of the extrusion die is flush with the second end of the extrusion sleeve. The pressing plate is installed outside the second end of the extrusion sleeve to press the extrusion die; The second control cabinet controls the punch drive motor and the resistance wire; The copper-aluminum rods are placed in the extrusion sleeve, and the extrusion punch applies pressure to the copper-aluminum rods, so that the copper-aluminum rods are extruded from the stepped rectangular holes of the extrusion die to form a strip-shaped copper-clad aluminum sheet blank.

7. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 1, It is characterized in that In step S4, the high-frequency ultrasonic assisted stamping and extension device includes a third upper support frame, a third workbench, a third pillar, a third upper slide, a third lower slide, a slide connecting rod, a third hydraulic cylinder, a third oil inlet pipe, a third oil return pipe, a third hydraulic oil tank, a third hydraulic pump, a third high-frequency ultrasonic generator, a third transducer, a third amplitude rod, an amplitude rod fixing seat, a stamping and extension punch, a lower support frame, a stamping and extension die and a third control cabinet; The third upper support frame is located above the third workbench; A plurality of third pillars pass through the third upper support frame and the third workbench to connect the third upper support frame and the third workbench into one; The third upper slide and the third lower slide are slidably sleeved on a plurality of third pillars and connected to form a third slide through a plurality of slide connecting rods. The third slide is located between the third upper support frame and the third workbench; The third hydraulic cylinder is installed on the top of the third upper support frame, the oil inlet is connected to the oil outlet of the third hydraulic pump through the third oil inlet pipe, the oil return port is connected to the third hydraulic oil tank through the third oil return pipe, and the piston passes through the third upper support frame and is connected to the third upper slide frame; The oil inlet of the third hydraulic pump is connected to the third hydraulic oil tank; The horn fixing seat is installed on the third lower slide bracket; The third horn passes through the horn fixing seat and the third lower slide bracket, the top end is connected to the third transducer, and the bottom end is connected to the stamping extension punch; The third high-frequency ultrasonic generator is connected to the third transducer via a third wire; The lower support frame is installed on the third workbench and is provided with a through hole; The punching and extension die is installed in the through hole; The third control cabinet controls the third hydraulic cylinder and the third high-frequency ultrasonic generator; The circular copper / aluminum / copper layered composite plate is placed in the annular positioning groove of the stamping and extension die.

8. The high-frequency ultrasonic assisted forming method of the copper-aluminum layered composite tube according to claim 1, It is characterized in that In step S5, the high-frequency ultrasonic assisted spinning machine includes a fourth box, a mandrel, a mandrel fixing mechanism, a mandrel drive motor, a fourth high-frequency ultrasonic generator, an axial track, a fourth transducer, a fourth amplitude rod, a ball, a tightening shaft, a fourth hydraulic cylinder, a fourth hydraulic pump, a fourth hydraulic oil tank, a first rotating wheel, a second rotating wheel, a third rotating wheel and a fourth control cabinet; The mandrel fixing mechanism is installed in the fourth box body; The spindle drive motor is installed outside the fourth box body; The mandrel is disposed transversely in the fourth housing, and the input end is connected to the mandrel drive motor through the mandrel fixing mechanism, and is driven to rotate by the mandrel drive motor; The tightening shaft is arranged transversely in the fourth box body, at the same height as the core shaft, and the input end passes through the fourth box body and is connected to the fourth hydraulic cylinder, and is driven by the fourth hydraulic cylinder to extend and retract transversely; The oil inlet of the fourth hydraulic cylinder is connected to the oil outlet of the fourth hydraulic pump through a fourth oil inlet pipe, and the oil return port is connected to the fourth hydraulic oil tank through a fourth oil return pipe; The oil inlet of the fourth hydraulic pump is connected to the fourth hydraulic oil tank; The first rotating wheel, the second rotating wheel and the third rotating wheel are all rotatably mounted in the fourth box body and can move axially along the core shaft. The first rotating wheel and the second rotating wheel are located below the core shaft, and the third rotating wheel is located above the core shaft. The axial track is installed in the fourth box; The fourth transducer is slidably mounted on the axial track; The bottom end of the fourth horn is connected to the fourth transducer, and the top end is connected to the ball bearing; The fourth high-frequency ultrasonic generator is connected to the fourth transducer via a fourth wire; The fourth control cabinet controls the spindle drive motor, the fourth hydraulic cylinder, the first rotating wheel, the second rotating wheel, the third rotating wheel and the fourth high-frequency ultrasonic generator; The copper / aluminum / copper layered composite tube blank is sleeved on the output end of the core shaft and is tightened by the output end of the tightening shaft, and the outer wall is in contact with the first rotating wheel, the second rotating wheel, the third rotating wheel and the ball.

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