A copper-aluminum dissimilar interface melting and forging method and device

Abstract

The present application discloses a copper-aluminum dissimilar interface melting and forging method and device, the method comprising: horizontally docking multiple groups of copper wires and multiple groups of aluminum wires and fixing them on a welding table; determining the positions of each dislocated welding point based on the radius of the cable composed of the copper wires and the aluminum wires and the total number of wire layers; adjusting the first angle component and the second angle component so that the welding laser beam and the forging laser beam are irradiated on the connecting welding point of the copper wire and the aluminum wire; adjusting the parameters of the welding laser beam and the forging laser beam to weld and laser forge the welding point. The present application utilizes the cooperation of dual lasers to improve the residual compressive stress, tensile strength, etc. of the weld, while achieving high efficiency of copper-aluminum laser welding, it also ensures the strength, hardness and other performance indicators of the weld and saves energy consumption.

Description

Technical Field

[0001] The present application belongs to the field of laser technology, and specifically relates to a copper-aluminum dissimilar interface melting and forging method and device. Background Art

[0002] Laser welding of copper / aluminum dissimilar interfaces is an efficient, precise and controllable welding method. This process uses the high energy density of the laser beam to heat the copper / aluminum material to above the melting point, causing it to melt and form a weld, thereby achieving material connection. However, the physical properties of copper / aluminum metals are quite different. During the welding process, after the aluminum is overheated, the copper may not have melted yet, resulting in welding difficulties. In addition, after cooling, the composition of the welding molten forging zone is uneven, and the residual stress of the copper / aluminum dissimilar metal weld is large, and defects such as pores and cracks are formed.

[0003] Laser shock forging is a new technology different from laser shock peening. Its working principle is that laser shock forging is generally used at high temperatures of 800°C to 1200°C, and is directly irradiated on medium and high temperature areas without any protective layer or constraint layer. The medium and high temperature cladding layer absorbs laser energy and ionizes and vaporizes on the surface of the cladding layer to produce high-pressure shock waves, which have a significant effect on reducing joint defects and improving the overall performance of the joint.

[0004] At present, the most common method to eliminate residual stress is to perform welding treatment and post-weld heat treatment on the welded workpiece. The welding treatment refers to a series of treatment measures carried out near the welded area while the welding operation is being carried out, mainly including welding rolling, welding rotation extrusion, welding hammering, vibration welding, welding chilling, welding pre-stretching and welding electromagnetic induction. The existing welding treatment technology lacks intelligence and precision, and has certain limitations for the treatment of welded parts with complex structures, and cannot better eliminate weldment defects; post-weld heat treatment refers to a treatment measure applied to the welded part after the welding operation is completed, that is, the weldment is heated to a certain temperature and kept warm for a certain period of time, and the yield limit of the material is reduced at high temperature, so that plastic flow occurs in places with high internal stress, elastic deformation gradually decreases, and plastic deformation gradually increases to reduce stress. Post-weld treatment is to treat the welded area after cooling. Its plastic deformation is small, and it is difficult to completely eliminate internal residual stress, deformation, microcracks and other defects. The complexity of the weldment heating device will increase exponentially with the increase in the size of the deposited parts and the increase in structural complexity. The efficiency of heating after the weldment is cooled is low, which wastes energy. Summary of the invention

[0005] The present application provides a copper-aluminum dissimilar interface fusion forging method and device to solve the above-mentioned technical problems.

[0006] In order to solve the above technical problems, a technical solution adopted in the present application is: a copper-aluminum dissimilar interface melting and forging method, comprising:

[0007] Step S1. horizontally docking multiple groups of copper wires and multiple groups of aluminum wires and fixing them on a welding table; wherein the interfaces between the copper wires and the aluminum wires are welding points, and the welding points are arranged in a staggered manner;

[0008] Step S2. Determine the positions of each dislocated welding point based on the radius of the cable composed of the copper wire and the aluminum wire and the total number of layers of the wire;

[0009] Step S3. Based on the position of the welding point, adjust the first angle component and the second angle component so that the welding laser beam and the forging laser beam are irradiated on the welding point where the copper wire and the aluminum wire are connected;

[0010] Step S4: Control the welding wire to the welding spot, adjust the parameters of the welding laser beam and the forging laser beam to weld the welding spot and perform laser forging.

[0011] Further, the specific method of step S2 includes:

[0012] Step S21. Based on the total number of layers of wires and the number of solder joints in each layer, obtain the number of layers and the order of the current solder joints;

[0013] Step S22. Determine whether the number of layers of the front solder joint is not greater than the total number of layers;

[0014] Step S23. In response to the number of layers of the current welding point being greater than the total number of layers, ending welding;

[0015] Step S24. In response to the number of layers of the current solder joint being not greater than the total number of layers, determine whether the number of the previous solder joints is not greater than the number of solder joints of the current layer, and calculate the coordinates of the solder joints.

[0016] Further, the specific method of step S24 includes:

[0017] Step S241. In response to the ranking of the current solder joint being not greater than the total number of solder joints of the current layer, obtaining the coordinates of the current solder joint;

[0018] Step S242. In response to the number of solder joints in the current ranking being greater than the current number of layers, the number of layers and the ranking of the previous solder joint are increased by one, and the process returns to step S22.

[0019] Furthermore, the specific method of obtaining the coordinates of the front welding point in step S241 includes:

[0020] Based on formula (1), the welding angle of the welding point is obtained; wherein formula (1) is:

[0021]

[0022] Where angle represents the welding angle, j represents the serial number of the current welding point, and N represents the total number of welding points;

[0023] Based on the welding angle of the welding point, a coordinate system is established with the center of the cable as the origin to obtain the coordinates of the current welding point;

[0024] Based on formula (2), the coordinates of the current welding point are obtained; wherein formula (2) is:

[0025]

[0026] Wherein, (x, y, z) is the coordinate of the welding point, Offest is the axial offset distance of the welding point of the current layer relative to the origin, and R is the radius of the circle layer where the welding wire of the current layer is located.

[0027] Another technical solution adopted in the present application is: a copper-aluminum dissimilar interface melting and forging device, comprising:

[0028] Laser impact forging equipment, used to laser forge the weld points to eliminate the residual compressive stress of the weld;

[0029] Laser welding machine, used to weld the welding points;

[0030] A wire feeding system 3, used for feeding the welding wire into the welding spot;

[0031] Welding table, used to carry copper wire and aluminum wire and perform welding;

[0032] The angle assembly comprises a first angle adjustment assembly for adjusting a welding laser and a second angle adjustment assembly for adjusting a punching and forging laser.

[0033] Further, the first angle adjustment component includes:

[0034] The first X-axis galvanometer is used to receive the welding laser emitted by the laser welding machine;

[0035] The first Y-axis galvanometer is used to reflect the welding laser reflected by the first X-axis galvanometer to the welding point.

[0036] Further, the second angle adjustment component includes:

[0037] The second X-axis galvanometer is used to receive the impact forging laser emitted by the laser impact forging equipment;

[0038] The second Y-axis galvanometer is used to reflect the punching laser reflected by the second X-axis galvanometer to the welding point.

[0039] The beneficial effects of the present application are as follows: the laser welding machine of the present application can weld copper / aluminum conductors quickly and efficiently, and the laser impact forging equipment performs laser impact forging on the metal surface in the medium and high temperature area formed by laser welding, and utilizes the coordinated effect of dual lasers to achieve improvements in the residual compressive stress, tensile strength, etc. of the weld. While achieving high efficiency in copper / aluminum laser welding, it also ensures the strength, hardness and other performance indicators of the weld, and saves energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the process of an embodiment of the copper-aluminum dissimilar interface melting and forging method of the present application;

[0041] Figure 2 This is a diagram of the staggered welding of copper and aluminum conductors in a cable flexible joint according to an embodiment of the copper and aluminum dissimilar interface melting and forging method of the present application;

[0042] Figure 3 for Figure 1 A schematic flow chart of an embodiment of step S2 in FIG.

[0043] Figure 4 for Figure 3 A schematic flow chart of an embodiment of step S24 in FIG.

[0044] Figure 5 This is a schematic diagram of a copper-aluminum dissimilar interface laser melting and forging combined cross-section of an embodiment of a copper-aluminum dissimilar interface melting and forging method of the present application;

[0045] Figure 6 It is a structural schematic diagram of an embodiment of the copper-aluminum dissimilar interface melting and forging device of the present application. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific embodiments.

[0047] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0048] See also Figure 1 , Figure 1 1 is a schematic flow chart of an embodiment of a copper-aluminum dissimilar interface melting and forging method of the present application. The method comprises:

[0049] Step S1. horizontally connect multiple groups of copper wires and multiple groups of aluminum wires and fix them on a welding table; wherein the interfaces between the copper wires and the aluminum wires are welding points, and the welding points are arranged in a staggered manner.

[0050] For details, see Figure 2, place the copper wire in the cable and the aluminum wire that needs to be connected on the welding table, where the connecting points of the copper and aluminum wires are welding points, and each welding point is staggered with each other.

[0051] Step S2: Determine the positions of each misaligned welding point based on the radius of the cable composed of the copper wire and the aluminum wire and the total number of layers of the wire.

[0052] For details, see Figure 3 , Figure 3 for Figure 1 Schematic diagram of the process of step S2 in an embodiment. Step S2 includes:

[0053] Step S21. Based on the total number of layers of the conductor and the number of solder joints in each layer, the number of layers and the order of the current solder joints are obtained.

[0054] Specifically, the number of conductor layers in the cable and the number of welding points in each layer are input, and then welding is performed starting from the conductor at the center and then to the welding points of the outer layers in sequence;

[0055] Step S22: Determine whether the number of layers of the front solder joint is not greater than the total number of layers.

[0056] Specifically, it is determined whether the circle layer of the current welding point is within the total circle layer.

[0057] Step S23: In response to the number of layers of the current welding point being greater than the total number of layers, welding is terminated.

[0058] Specifically, if the number of circles of the front welding point is greater than the total number of layers, it is determined that the cable welding is completed and the welding is finished.

[0059] Step S24. In response to the number of layers of the current solder joint being not greater than the total number of layers, determine whether the number of the previous solder joints is not greater than the number of solder joints of the current layer, and calculate the coordinates of the solder joints.

[0060] For details, see Figure 4 , Figure 4 for Figure 3 The flowchart of step S24 in the embodiment of step S24 includes:

[0061] Step S241. In response to the ranking of the current solder joint being not greater than the number of solder joints in the current layer, obtaining the coordinates of the current solder joint.

[0062] Specifically, if the ranking of the current welding point does not exceed the number of welding points in the current circle, it is considered that the current welding point can be welded.

[0063] Based on formula (1), the welding angle of the welding point is obtained; wherein formula (1) is:

[0064]

[0065] Wherein, angle represents the welding angle, j represents the serial number of the current welding point, N represents the total number of layers of welding points, (x, y, z) represents the coordinates of the welding points, and R represents the radius of the circle where the welding wire of the current layer is located.

[0066] Taking the center of the cable as the origin of polar coordinates, we can know that the polar coordinate position of the welding point is (R, angle).

[0067] Based on the welding angle of the welding point and the polar coordinates of the welding point, a Cartesian coordinate system is established with the center of the cable as the origin to obtain the coordinates of the current welding point;

[0068] Based on formula (2), the coordinates of the current welding point are obtained; wherein formula (2) is:

[0069]

[0070]

[0071] Among them, Offest is the axial offset distance of the current layer welding point relative to the origin.

[0072] Follow the above steps to record the coordinates of each welding point one by one.

[0073] Step S242. In response to the ranking of the current solder joint being greater than the total number of solder joints in the current layer, the number of layers and the ranking of the previous solder joint are increased by one, and the process returns to step S22.

[0074] Specifically, if the ranking of the current welding point is greater than the total number of welding points of the current layer, the welding point coordinates of the next circle layer are calculated.

[0075] Step S3. Based on the position of the welding point, adjust the first angle component and the second angle component so that the welding laser beam and the forging laser beam are irradiated on the connecting welding point of the copper wire and the aluminum wire.

[0076] Specifically, the coordinate position of each welding point is recorded, the laser power and welding speed are controlled, and the welding laser beam with appropriate parameters is injected into the welding point, and the defects are minimized by controlling the welding power and welding speed.

[0077] Step S4: Control the welding wire to the welding spot, adjust the parameters of the welding laser beam and the forging laser beam to weld the welding spot and perform laser forging.

[0078] For details, see Figure 5 , monitor and control the wire feeding speed. When the wire feeding speed is greater than the melting speed, the unmelted wire will affect the welding quality; when the wire feeding speed is too slow, it will cause insufficient filler metal; when the wire feeding speed is unstable, it will cause an uneven weld.

[0079] When the laser beam is used for welding, according to the maximum temperature T of the weld spot, the welding time t and the power P of the laser welder, the heat conduction equation, the thermal physical properties of the composite material and the welding parameters (such as speed, power, etc.) can be used to simulate the temperature distribution during welding, and then estimate the size and affected depth of the heat affected zone (HAZ).

[0080] The required impact forging laser power is calculated based on the target of laser impact forging, the characteristics of HAZ, and the physical model of the interaction between laser and material.

[0081] According to the calculated impact forging laser power, the parameter setting of the impact forging laser is adjusted to perform impact forging on the completed weld spot.

[0082] See also Figure 6 , Figure 6 It is a structural schematic diagram of an embodiment of the copper-aluminum dissimilar interface melting and forging device of the present application, which includes: laser impact forging equipment 1, laser welding machine 2, wire feeding system 3, welding table 4 and angle assembly 5.

[0083] The laser impact forging equipment 1 is used to perform laser forging on the welding spot to eliminate the residual compressive stress of the weld; the laser welding machine 2 is used to weld the welding spot; the wire feeding system 3 is used to feed the welding wire into the welding spot; the welding table 4 is used to carry the copper guide wire and the aluminum guide wire and perform welding; the angle component 5 includes a first angle adjustment component 51 for adjusting the welding laser and a second angle adjustment component 52 for adjusting the impact forging laser.

[0084] The first angle adjustment component 51 includes: a first X-axis galvanometer 511 and a first Y-axis galvanometer 512; the first X-axis galvanometer 511 is used to receive the welding laser emitted by the laser welding machine 2; the first Y-axis galvanometer 512 is used to reflect the welding laser reflected by the first X-axis galvanometer 511 to the welding point.

[0085] The second angle adjustment assembly 52 includes: a second X-axis galvanometer 521 and a second Y-axis galvanometer 522. The second X-axis galvanometer 521 is used to receive the impact forging laser emitted by the laser impact forging device 1; the second Y-axis galvanometer 522 is used to reflect the impact forging laser reflected by the second X-axis galvanometer 521 to the welding point.

[0086] The laser welding machine 2 in the present application has the characteristics of fast welding speed, high precision, and the ability to weld a variety of materials. It can weld copper / aluminum wires quickly and efficiently. The laser impact forging equipment 1 performs laser impact forging on the metal surface in the medium and high temperature area formed by laser welding, and utilizes the coordinated effect of dual lasers to achieve an improvement in the residual compressive stress and tensile strength of the weld. While achieving high efficiency in copper / aluminum laser welding, it also ensures the strength, hardness and other performance indicators of the weld.

[0087] The above description is only an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A copper-aluminum dissimilar interface melting and forging method, characterized in that: The following steps are involved: Step S1. horizontally docking a plurality of groups of copper wires and a plurality of groups of aluminum wires and fixing them on a welding table; wherein the interfaces between the copper wires and the aluminum wires are welding points, and the welding points are arranged in a staggered manner; Step S2. Based on the radius of the cable joint composed of the copper wire and the aluminum wire and the total number of wire layers, determine the positions of each of the dislocated welding points; wherein step S2 includes: Step S21. Based on the total number of layers of the wire and the number of solder joints in each layer, obtain the number of layers and the order of the current solder joints; Step S22: Determine whether the number of layers of the current solder joint is not greater than the total number of layers; Step S23. In response to the number of layers of the current welding point being greater than the total number of layers, ending welding; Step S24. In response to the number of layers of the current solder joint being not greater than the total number of layers, determining whether the order of the current solder joint is not greater than the number of solder joints of the current number of layers, and calculating the coordinates of the solder joint; wherein the method for obtaining the coordinates of the current solder joint includes: Based on formula (1), the welding angle of the welding point is obtained; wherein the formula (1) is: Where angle represents the welding angle, j represents the serial number of the current welding point, and N represents the total number of welding points; Based on the welding angle of the welding point, a coordinate system is established with the center of the cable connector as the origin to obtain the coordinates of the current welding point; Based on formula (2), the coordinates of the current welding point are obtained; wherein formula (2) is: from=Offest(2); Wherein, (x, y, z) are the coordinates of the welding point, Offest is the axial offset distance of the welding point of the current layer relative to the origin, and R is the radius of the circle layer where the welding wire of the current layer is located; Step S3. Based on the position of the welding point, adjust the first angle component and the second angle component so that the welding laser beam and the forging laser beam are respectively reflected by the first angle component and the second angle component and irradiate the welding point at the connection between the copper wire and the aluminum wire; Step S4. Control the welding wire to the welding spot, adjust the parameters of the welding laser beam and the forging laser beam to weld the welding spot and perform laser forging.

2. The method according to claim 1, characterized in that: The specific method of step S24 includes: Step S241. In response to the ranking of the current solder joint being not greater than the number of solder joints in the current layer, obtaining the coordinates of the current solder joint; Step S242: In response to the ranking of the current solder joint being greater than the total number of solder joints in the current layer, the number of layers and the ranking of the previous solder joint are increased by one, and the process returns to step S22.

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