CN116727833A

CN116727833A - Welding device and welding method

Info

Publication number: CN116727833A
Application number: CN202310762158.1A
Authority: CN
Inventors: 张莹; 李谷南; 王继成; 蓝志平; 蒋洪洲; 任怀德
Original assignee: Zhuhai Runxingtai Electrical Equipment Co Ltd
Current assignee: Zhuhai Runxingtai Electrical Equipment Co Ltd
Priority date: 2023-06-26
Filing date: 2023-06-26
Publication date: 2023-09-12

Abstract

The invention discloses a welding device and a welding method. The fixture is used for placing the first workpiece and the second workpiece, the fixture is provided with a welding track part, and the welding track part is provided with a reverse deformation structure. The pin stirring head comprises a first shaft shoulder and a stirring pin, wherein the first shaft shoulder is provided with a first welding plane, and the stirring pin protrudes out of the first welding plane. The needleless stirring head comprises a second shoulder having a second welding plane. Wherein the pin stirrer and the pin-less stirrer are both configured to be located on one side of the clamp and movable relative to the clamp to friction weld the first workpiece and the second workpiece on the clamp. The welding device and the welding method applied to the welding device overcome the problems of welding defects and out-of-flatness in the existing welding process, and ensure that the flatness of the welded product is controlled below 0.4 mm.

Description

Welding device and welding method

Technical Field

The invention relates to the technical field of welding, in particular to a welding device and a welding method.

Background

The structure of the current electric control box body of the new energy automobile tends to be integrated and complex, the water channel part is positioned at the bottom of a deeper cavity (about 100 mm), and the water channel cover plate is a friction stir welding process of 6061 aluminum profile and ADC12 die casting aluminum alloy material of the box body. Friction stir welding is a solid state welding method that achieves welding. Under the action of pressure, relative movement between welding contact end surfaces is utilized to generate friction heat and plastic deformation heat at a friction surface and a nearby area thereof under the action of constant or increasing pressure and torque, so that the temperature of the nearby area thereof is increased to a temperature range close to but generally lower than a melting point, the deformation resistance of the material is reduced, the plasticity is improved, an oxide film of an interface is broken, plastic deformation and flow are generated along with the material under the action of top forging pressure, and the solid welding method for welding is realized through molecular diffusion and recrystallization of the interface.

Because the new energy automobile electric cabinet water course belongs to the dissimilar material connection between 6061 aluminum profile and ADC12 die-casting aluminum alloy, and the welding depth reaches 5mm, the product compression dynamics is bigger and the welding seam merges the degree of depth that is darker in the welding process, and current friction stir welding technique is influenced by factors such as stirring head type, the atress support of anchor clamps, and current friction stir welding technique can't eliminate completely and avoid the welding defect that the welding seam appears the tunnel to and appear great (more than 1.0 mm) welding deformation defect after the welding, can't satisfy the processing of later stage.

Disclosure of Invention

The embodiment of the invention provides a welding device and a welding method for solving the technical problems of weld joint welding defects and welding deformation defects in a friction stir welding process in the prior art.

In order to solve the above technical problem, in one aspect, an embodiment of the present invention provides a welding device for friction welding a first workpiece and a second workpiece, the welding device including:

the fixture is used for placing the first workpiece and the second workpiece, a welding track part is arranged on the fixture, and a reverse deformation structure is arranged at the welding track part;

a pin stirring head comprising a first shaft shoulder and a stirring pin, wherein the first shaft shoulder is provided with a first welding plane, and the stirring pin protrudes out of the first welding plane; and

a needleless stirring head comprising a second shoulder having a second welding plane;

wherein the pin stirrer and the pin-less stirrer are both configured to be located on one side of the jig and movable relative to the jig to friction weld the first and second workpieces on the jig.

In some embodiments, the clamp comprises a clamping device, wherein the clamping device comprises an actuating element, a connecting mechanism and a force application piece, and the actuating element is connected with the force application piece through the connecting mechanism so as to drive the force application piece to swing;

the force application part is provided with a force application position and a separation position when swinging, the force application part positioned at the force application position applies force to the first workpiece and/or the second workpiece to fix the first workpiece and/or the second workpiece on the clamp, and the force application part positioned at the separation position is separated from the first workpiece and the second workpiece.

In some embodiments, the actuator is a cylinder or ram having a cylinder body and a piston rod;

the connecting mechanism comprises a connecting seat and a hinging piece, wherein the connecting seat is fixed on the cylinder body and is positioned on one side of the piston rod, one end of the hinging piece is hinged with the connecting seat, the other end of the hinging piece is hinged between two ends of the force application piece, and one end of the force application piece is hinged with the piston rod.

In some embodiments, the force application member includes a connecting portion, a terminal end of the connecting portion is provided with a first extension portion extending vertically to a side portion thereof, and a terminal end of the first extension portion is provided with a second extension portion in the same direction as the connecting portion;

one end of the connecting part is hinged with the piston rod, and the connecting part of the connecting part and the first extending part is hinged with the hinge piece;

when the force application piece is positioned at the force application position, the second extension part presses down the first workpiece and/or the second workpiece to apply force; and a supporting piece is arranged below the second extension part.

In some embodiments, the fixture further comprises a welding die that mates with the first workpiece and/or the second workpiece, the welding track location and the reverse deformation structure being located on the welding die.

In some embodiments, the fixture further comprises a positioning member, wherein a positioning structure is arranged on the first workpiece and/or the second workpiece, and the positioning member is matched with the positioning structure, so that the first workpiece and/or the second workpiece are positioned and placed on the fixture.

On the other hand, the embodiment of the invention also provides a welding method which is applied to the welding device, and comprises the following steps:

the first workpiece and the second workpiece are assembled and placed on the clamp, a welding track part is arranged on the clamp, and a reverse deformation structure is arranged on the welding track part;

the needleless stirring head moves relative to the clamp according to a preset welding track, and friction welding is carried out on the first workpiece and the second workpiece on the clamp;

and the pin stirring head moves relative to the clamp according to the preset welding track, and friction welding is carried out on the first workpiece and the second workpiece on the clamp.

In some embodiments, the needleless stirring head moves relative to a clamp according to a preset welding track, performs friction welding on the first workpiece and the second workpiece on the clamp, and comprises at least one of the following characteristics:

the welding speed of the needleless stirring head is 300-400mm/min;

the needleless stirring head adopts a pressure constant mode for welding.

In some embodiments, the pin stirring head moves relative to a clamp according to the preset welding track, and performs friction welding on the first workpiece and the second workpiece on the clamp, including at least one of the following features:

the welding speed of the pin stirring head is 200-300mm/min;

the pin stirring head adopts a pressure constant mode for welding.

In some embodiments, one of the first and second workpieces is 6061 aluminum and the other is ADC12 die cast aluminum alloy.

The embodiment of the invention has the following beneficial effects: the welding device and the welding method applied to the welding device overcome the problems of welding defects and out-of-flatness in the existing welding process, ensure that the flatness of the welded product is controlled below 0.4mm, and ensure that the welded weld has no welding defects such as tunnels and the like.

Drawings

FIG. 1 is a schematic view of a first embodiment of a welding apparatus according to the present invention;

FIG. 2 is an operational state diagram of FIG. 1;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a schematic diagram of the weld of FIG. 3;

FIG. 5 is another operational state diagram of FIG. 1;

FIG. 6 is a cross-sectional view taken along B-B in FIG. 5;

FIG. 7 is a schematic diagram of the weld of FIG. 6;

FIG. 8 is an enlarged partial view of region C shown in FIG. 7;

fig. 9 is a perspective view of fig. 5;

FIG. 10 is a schematic view of the fixture of FIG. 9 after concealing the weld mold;

FIG. 11 is a schematic view of the structure of the clamping device of FIG. 10;

fig. 12 is a flowchart of a first embodiment of a welding method of the present invention.

Reference numerals illustrate:

100. a clamp; 110. a clamping device; 111. an actuator; 112. a force application member; 1121. a connection part; 1122. a first extension; 1123. a second extension; 113. a connecting seat; 114. a hinge; 115. a support; 116. welding a die; 1161. welding track parts; 117. a positioning piece; 200. a pin stirring head; 210. a first shoulder; 220. a stirring pin; 300. a needle-free stirring head; 310. a second shoulder; 400. a first workpiece; 410. a positioning structure; 500. and a second workpiece.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings, for the purpose of making the objects, technical solutions and advantages of the present invention more apparent. It is only stated that the terms of orientation such as up, down, left, right, front, back, inner, outer, etc. used in this document or the imminent present invention, are used only with reference to the drawings of the present invention, and are not meant to be limiting in any way.

In the present invention, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

The description as it relates to "first", "second", etc. in the present invention is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.

In one embodiment of the present invention, as shown in fig. 1 to 9, a welding apparatus is provided for friction welding a first workpiece 400 and a second workpiece 500. Specifically, the term "friction welding" refers to a method of welding by using heat generated by friction of a workpiece contact surface as a heat source, and causing plastic deformation of the workpiece under pressure. Preferably, during the whole welding process, at least one of the following steps is included: the stirring head rotates, inserts, metal plasticizes and advances.

In one embodiment, the first and second workpieces 400 and 500 are a tank and a waterway cover, respectively, but the present invention is not limited to the two types of workpieces described above. In one embodiment, one of the first workpiece 400 and the second workpiece 500 is made of 6061 aluminum and the other is made of ADC12 die-cast aluminum, but the present invention is not limited to the above materials, and other metal materials are generally applicable.

As shown in fig. 1, the welding apparatus includes a jig 100, a pin stirrer 200, and a pin-less stirrer 300. The pin head 200 and the pin head 300 are mounted on a friction stir welding apparatus having X, Y, Z moving means so that the pin head 200 and the pin head 300 move relative to the first workpiece 400 and the second workpiece 500 to be able to weld along a preset welding trajectory. In more detail, in an embodiment of the present invention, the friction stir welding apparatus includes: the machine base is provided with a slidable workbench, the rear side of the machine base is provided with a stand column in a sliding mode, the front end of the stand column is provided with a main shaft assembly in a sliding mode, the workbench is arranged right below the main shaft assembly, and the workbench is used for placing workpieces to be welded. The workbench is provided with an X-axis movement device, the upright post is provided with a Y-axis movement device and a Z-axis movement device, the spindle assembly is mounted on the Z-axis movement device, and the needle stirring head 200 and the needleless stirring head 300 can be connected with the spindle assembly.

The jig 100 is used to place the first workpiece 400 and the second workpiece 500, and generally, the first workpiece 400 and the second workpiece 500 are placed on the jig 100 after assembly, but the first workpiece 400 as a main body may be placed on the jig 100 first and then the second workpiece 500 may be assembled on the first workpiece 400. The jig 100 has a welding locus 1161, and the welding locus 1161 is provided with a reverse deformation structure. The welding track portion 1161 matches the preset welding track when the first workpiece 400 and the second workpiece 500 are welded, i.e., the shape and the size of both are matched. As one embodiment of the present invention, the "reverse deformation structure" refers to a structure in which a reverse deformation is set on the jig 100 according to a rule of deformation occurring in a welding process in the past, and the deformation is made to be equal in magnitude and opposite in direction to the deformation occurring after welding, so as to cancel the welding deformation. For example, in the past welding process, one of the welding parts is deformed downwards, and the designed reverse deformation structure is a convex structure, so that the welding deformation is counteracted, and the flatness after welding is ensured.

Pin mixing head 200 includes a first shoulder 210 and a pin 220, first shoulder 210 including a first welding plane, pin 220 protruding from the first welding plane. Needleless stirring head 300 includes a second shoulder 310, second shoulder 310 having a second weld plane on which there is no protruding stirring pin due to needleless stirring head 300.

Wherein pin stirring head 200 and pin-less stirring head 300 are each configured to be located on one side (generally the upper side) of jig 100 and movable relative to jig 100 to friction weld first workpiece 400 and second workpiece 500 on jig 100.

In the prior art, only a pin stirring head is adopted for welding in welding, and as the pin stirring head applies axial force and transverse force to a welding part, the transverse force causes welding defects of unwelded materials in the welding process. The invention firstly performs pre-welding through the needleless stirring head 300 to form a preset welding bead, only axial force is applied to the welding part in the process, welding defects are reduced, and then fine welding is performed along the preset welding bead through the needleless stirring head 200, so that the welding combination degree is enhanced.

The welding device and the welding method applied to the welding device overcome the problems of welding defects and out-of-flatness in the existing welding process, ensure that the flatness of the welded product is controlled below 0.4mm, and ensure that the welded weld has no welding defects such as tunnels and the like.

In some embodiments, as shown in fig. 1, the fixture 100 further includes a positioning member 117, where the positioning structure 410 is disposed on the first workpiece 400 and/or the second workpiece 500, and the positioning member 117 cooperates with the positioning structure 410 to position the first workpiece 400 and/or the second workpiece 500 on the fixture 100. Specifically, the present invention relates to a method for manufacturing a semiconductor device. The positioning member 117 is a positioning post, which extends upward, the positioning structure 410 is a positioning hole, and the positioning hole may be a hole on the original structure of the workpiece, when the first workpiece 400 and/or the second workpiece 500 are placed downward to the welding mold 116, the positioning post is inserted into the positioning hole, so as to position the first workpiece 400 and/or the second workpiece 500, and guide the first workpiece 400 and/or the second workpiece 500 to be accurately placed on the welding mold 116, so as to improve the alignment precision during welding.

In some embodiments, as shown in fig. 4 and 6, the fixture 100 further includes a welding die 116, the welding die 116 shape matching the first workpiece 400 and/or the second workpiece 500 to position the first workpiece 400 and/or the second workpiece 500 for more precise welding, the welding track location 1161 and the reverse deformation structure being located on the welding die 116. Generally, the welding mold 116 is matched with only the first workpiece 400 as a main body, and the first workpiece 400 is provided with a structure matched with the second workpiece 500, and the two workpieces can be matched and assembled together.

In some embodiments, as shown in fig. 9-11, the clip 100 includes a number of clamping devices 110, which may be one or more, preferably a plurality of clamping devices 110 located around the clip 100.

Specifically, as shown in fig. 11, the clamping device 110 includes an actuator 111, a connection mechanism, and a force application member 112, where the actuator 111 is connected to the force application member 112 through the connection mechanism to drive the force application member 112 to swing. Alternatively, the actuator 111 may be a pneumatic actuator, such as a cylinder; or hydraulic actuators, such as hydraulic cylinders; or an electric actuator, such as a motor. The term "force application member 112" refers to a member that can apply a downward force.

The urging member 112 has an urging position and a separation position when swinging, and the urging member 112 located at the urging position urges the first workpiece 400 and/or the second workpiece 500 to be fixed to the jig 100, and the urging member 112 located at the separation position is separated from the first workpiece 400 and the second workpiece 500.

When the first workpiece 400 and/or the second workpiece 500 need to be placed on the fixture 100, the force application member 112 is located at the separation position to avoid blocking the first workpiece 400 and/or the second workpiece 500 from being placed, and when the first workpiece 400 and/or the second workpiece 500 are placed, the force application member 112 swings from the separation position to the force application position to clamp the first workpiece 400 and/or the second workpiece 500, so as to avoid displacement or offset when welding.

In some embodiments, as shown in FIG. 11, the actuator 111 is a cylinder or ram having a cylinder 1111 and a piston rod 1112. The connecting mechanism comprises a connecting seat 113 and a hinge member 114, wherein the connecting seat 113 is fixed on the cylinder 1111 and is positioned at one side of the piston rod 1112, one end of the hinge member 114 is hinged with the connecting seat 113, the other end of the hinge member is hinged between two ends of the force application member 112, and one end of the force application member 112 is hinged with the piston rod 1112.

In some embodiments, as shown in fig. 11, the force application member 112 includes a connection portion 1121, a first extension portion 1122 extending vertically toward a side portion of the connection portion 1121 is provided at an end of the connection portion 1121, and a second extension portion 1123 extending in the same direction as the connection portion 1121 is provided at an end of the first extension portion 1122. One end of the connection 1121 articulates the piston rod and its connection with the first extension 1122 articulates the hinge 114.

When the force application member 112 is located at the force application position, the second extension portion 1123 presses the first workpiece 400 and/or the second workpiece 500 to apply force; a support 115 is provided below the second extension 1123.

The working principle of the clamping device 110 is described in detail with reference to the accompanying drawings: first, when the piston rod of the actuator 111 is in the contracted state, the end of the connecting portion 1121 hinged to the piston rod moves downward, and the second extension portion 1123 swings upward. Conversely, when the piston rod of the actuator 111 is extended, the end of the connecting portion 1121 hinged to the piston rod is moved upward, and the second extension portion 1123 swings downward and presses downward.

On the other hand, the embodiment of the invention also provides a welding method which is applied to the welding device, as shown in fig. 12, and comprises the following steps:

s101, assembling a first workpiece and a second workpiece, and placing the first workpiece and the second workpiece on a clamp, wherein the clamp is provided with a welding track part, and the welding track part is provided with a reverse deformation structure;

s102, enabling the needleless stirring head to move relative to the clamp according to a preset welding track, and performing friction welding on a first workpiece and a second workpiece on the clamp;

s103, the pin stirring head moves relative to the clamp according to a preset welding track, and friction welding is carried out on the first workpiece and the second workpiece on the clamp.

In the above welding method, step S102 is performed by pre-welding, and the pre-weld bead is formed by pre-welding, and step S103 is performed by finish welding, and the secondary welding is performed in the pre-weld bead, so that the welding defect can be reduced. The invention adopts the welding process combining the pre-welding and the finish welding and combines the clamp with reverse deformation, thereby overcoming the problems of welding defects and ultra-poor planeness of the existing welding process, controlling the planeness of the welded product to be below 0.4mm, and causing larger (more than 1.0 mm) welding deformation defects after the welding by the existing welding method, and causing no welding defects such as tunnels and the like of the welded seam.

In some embodiments, step S102 includes at least one of the following features:

the welding speed of the needleless stirring head is 300-400mm/min, more preferably 320-380mm/min, and still more preferably 340-360mm/min, so as to obtain better welding quality and welding efficiency. In some specific embodiments, the needleless stirring head has a welding speed of 300mm/min, 310mm/min, 320mm/min, 350mm/min, 360mm/min, 380mm/min.

The needleless stirring head adopts a pressure constant mode for welding.

In some embodiments, step S103 includes at least one of the following features:

the welding speed of the pin stirring head is 200-300mm/min; further preferably 220 to 280mm/min, and more preferably 240 to 260mm/min, to obtain good welding quality and welding efficiency. In some specific embodiments, the welding speed of the pin stirrer head is 200mm/min, 210mm/min, 230mm/min, 250mm/min, 260mm/min, 270mm/min, 280mm/min.

The pin stirring head adopts a constant pressure mode for welding.

The friction stir welding seam is well formed under the process parameters, because the fluidity and the formability of the material are good in the friction stir welding process, the material is in a high plastic state, and the stroke is attractive under the extrusion action of the shaft shoulder. When welding is performed at process parameters outside the above parameter ranges, the formability and flowability of the material are poor, and defects appear in the weld. The constant pressure mode generally refers to a welding being completed under constant pressure conditions. Illustratively, the weld axial force is typically in the range of 0.5kN to 2kN. In addition, the remaining process parameters may be selected according to the process requirements, and illustratively, the rotational speeds of the needleless stirring head and the needleless stirring head are generally 1000-20000r/min, and the pressing amount is generally 0.01-1.0mm.

In summary, the welding method provided by the invention performs two times of friction welding, and the welding process of pre-welding and finish welding ensures that the planeness of the welded product is controlled below 0.4mm and the welded seam has no welding defects such as tunnel and the like by selecting the welding speeds of the needleless stirring head and adopting a constant pressure mode for welding.

In some embodiments, one of the first and second workpieces is 6061 aluminum and the other is ADC12 die cast aluminum alloy. Namely, the welding method aims at the dissimilar material connection between the 6061 aluminum profile and the ADC12 die-casting aluminum alloy. The thermal expansion coefficient of the aluminum alloy is large, larger heat is generated during welding, and the longitudinal shrinkage deformation and the transverse shrinkage deformation of the welding line are overlapped and subjected to thermal deformation to form larger deformation. By adopting the welding device and the welding method, the welding performance and the quality of two different materials (ADC 12+6061) after friction welding are ensured to meet the technical requirements of design.

While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that changes and modifications may be made without departing from the principles of the invention, such changes and modifications are also intended to be within the scope of the invention.

Claims

1. A welding device for friction welding a first workpiece and a second workpiece, the welding device comprising:

2. The welding device of claim 1, wherein the clamp comprises a clamping device comprising an actuator, a connecting mechanism, and a force application member, the actuator being connected to the force application member by the connecting mechanism to drive the force application member to swing;

3. The welding apparatus of claim 2 wherein the actuator is a cylinder or ram, the cylinder or ram having a cylinder body and a piston rod;

4. The welding device as recited in claim 3, wherein said urging member includes a connecting portion, a distal end of said connecting portion being provided with a first extension portion extending perpendicularly to a side portion thereof, a distal end of said first extension portion being provided with a second extension portion in the same direction as said connecting portion;

5. The welding device as defined in any one of claims 1 to 4, wherein said fixture further comprises a welding die, said welding die matching said first workpiece and/or said second workpiece, said welding locus and said reverse deformation structure being located on said welding die.

6. The welding device as defined in any one of claims 1 to 4, wherein said fixture further comprises a locating feature provided on said first and/or second workpiece, said locating feature cooperating with said locating feature to locate said first and/or second workpiece on said fixture.

7. A welding method, characterized in that it is applied to a welding device according to any one of claims 1 to 6, said welding method comprising the steps of:

8. The welding method of claim 7, wherein the needleless stirring head moves relative to a fixture according to a preset welding track to perform friction welding on the first workpiece and the second workpiece on the fixture, and comprising at least one of the following features:

the welding speed of the needleless stirring head is 300-400mm/min;

the needleless stirring head adopts a pressure constant mode for welding.

9. The welding method of claim 7, wherein said pin header is movable relative to a fixture along said predetermined welding trajectory to friction weld said first workpiece and said second workpiece on said fixture, comprising at least one of the following features:

the welding speed of the pin stirring head is 200-300mm/min;

the pin stirring head adopts a pressure constant mode for welding.

10. The welding method according to any one of claims 7 to 9, characterized in that one of the first workpiece and the second workpiece is a 6061 aluminum profile and the other is an ADC12 die-cast aluminum alloy.