CN115815799A - Laser welding method, laser welding equipment, and laser welding assembly - Google Patents

Abstract

The present application provides a laser welding method, laser welding equipment and laser welding components. The laser welding method provided by this application includes: obtaining the weld seam type of the welding seam; selecting a matching double-beam laser according to the weld seam type; The light beam and the ring-shaped light beam surrounding the periphery of the central light beam and concentric with the central light beam. The laser welding method provided by this application uses a double-beam laser consisting of a central beam and a ring beam for welding. The ring beam is distributed around the center beam. The weak-intensity laser of the ring beam can not only preheat the welding base material, It can play the role of delaying the cooling speed of the weld seam, thereby improving the laser absorption efficiency of the metal material, and reducing the phenomenon of crack defects formed by the metal material during the cooling process of laser welding.

Description

Laser welding method, laser welding equipment, and laser welding assembly

technical field

The embodiment of the present application relates to the field of welding technology, and specifically relates to a laser welding method, laser welding equipment and a laser welding assembly.

Background technique

In the prior art, laser welding of metal materials is a rapid heating and cooling process. For the deep penetration welding process of the same metal material and dissimilar metal materials, if the keyhole stability in the weld pool is too poor, it is easy to Defects such as cracks and pores occur. Especially for laser welding of dissimilar metal materials (such as steel and copper), due to the difference in physical and chemical properties such as expansion coefficients of the two metals, it is easy to cause cracks in the weld under different stresses.

Contents of the invention

In view of the above problems, the embodiments of the present application provide a laser welding method, laser welding equipment and laser welding components. The laser welding method uses a double-beam laser for welding, and the double-beam laser is used to solve the problem of metal materials formed during the cooling process of the weld seam. Technical issues with crack defects.

The first aspect of the present application provides a laser welding method. The laser welding method includes: obtaining the weld type of the welding position; selecting a matching double-beam laser according to the weld type; controlling the laser emitter according to the matched double-beam laser A central beam corresponding to the central point of the welding position and an annular beam surrounding the periphery of the central beam and concentric with the central beam are generated.

The laser welding method provided in this embodiment uses a double-beam laser composed of a central beam and a ring beam for welding. The high-intensity laser of the center beam can play the role of melting and welding the base material. The ring beam is distributed around the center beam, and the ring beam The weak-intensity laser can not only play the role of preheating the welding base metal, but also can play the role of delaying the cooling speed of the weld, so as to reduce the phenomenon of crack defects in the metal material during the cooling process of laser welding, especially It can reduce the occurrence of crack defects in welds of dissimilar metal materials (such as steel and copper) during cooling.

In some embodiments, controlling the double-beam laser to generate a central beam corresponding to the central point of the welding position and an annular beam surrounding the periphery of the central beam and concentric with the central beam specifically includes: controlling the central beam to emit in a modulated pulse manner , and/or control the ring beam to emit in continuous wave mode. Setting the center beam as a modulated pulse laser can reduce the heat input of the center beam and reduce the burning loss and evaporation of low melting point alloy elements; the continuous preheating of the ring beam can increase the laser absorption rate of the welding base material and improve the welding efficiency. Stability, can also clean the surface of the welding base metal, volatilize low melting point pollutants, reduce spatter caused by low melting point pollutants, continuous preheating through the ring beam can also delay the cooling rate of the weld seam, reduce the local heat of the weld seam Stress, to avoid weld cracks.

In some embodiments, the central beam includes a tapered cylindrical beam whose outer diameter gradually increases from high to low, and/or the annular beam includes a tapered cylindrical beam whose outer diameter gradually increases from high to low. By arranging both the central beam and the ring beam in a cone-shaped structure, the effective welding area of the double-beam laser can be increased, and the welding efficiency of the double-beam laser can be improved.

In some embodiments, the tapered cylindrical light beam includes an inner wall surface and an outer wall surface spaced along the radial direction of the tapered cylindrical light beam, and the cross section formed by the inner wall surface and the outer wall surface along the height direction is an inverted V-shaped structure. The inner wall and the outer wall can increase the spot area of the ring beam projected on the welding base metal, thereby increasing the effective area of the ring beam, improving the preheating effect and slow cooling effect of the ring beam, and reducing the welding of the base metal during welding. Defects such as cracks.

In some embodiments, selecting the matching center beam and ring beam according to the weld type specifically includes: determining the spot diameter of the center beam as d and the spot diameter of the ring beam as D according to the weld type, wherein the ratio of D and d satisfies 2≤D/d≤10. D/d≥2 can ensure that the spot diameter of the ring beam is at least 1 times the spot diameter of the center beam. Since the center beam is concentric with the ring beam, the part of the ring beam whose diameter exceeds the center beam can play the role of preheating and slow cooling. And the effect of cleaning the surface of the weld; D/d≤10 is to avoid the excessive heat-affected zone range caused by the excessive diameter of the annular beam spot, which leads to the coarsening of the welding area of the welding base metal and affects the performance of the base metal. .

In some embodiments, selecting a matching dual-beam laser according to the type of weld specifically includes: determining the power of the central beam as p and the power of the ring beam as P according to the type of weld, wherein the ratio of P to p satisfies 1≤P/ p≤6. P/p≥1 is considering that the spot diameter of the annular beam is at least twice the spot diameter of the central beam, and the beam energy distribution of the general laser is Gaussian distribution, the middle energy is high, and the peripheral energy is low. If the energy (power) of the ring beam If it is too low, the energy of the peripheral part of the ring beam beyond the diameter of the central beam is lower, and the effect of preheating and cooling and cleaning the surface is not significant; P/p≤6 is to avoid the heat input of the ring beam from being too high. Causes burning loss and evaporation of low melting point alloying elements.

In some embodiments, controlling the ring-shaped beam to emit in a continuous wave specifically includes: controlling the power of the ring-shaped beam to gradually increase to a preset working power during the arc-on stage of welding; and/or controlling the power of the ring-shaped beam to The preset operating power is gradually reduced. The slow rise of the annular beam at the arc start can weaken the "matchhead" appearance of the welding seam at the arc start point, and the slow decline at the arc stop can reduce the arc crater depression of the weld at the arc stop.

In some embodiments, controlling the ring-shaped beam to emit in a continuous wave manner further includes: controlling the power of the ring-shaped beam to form a stable working stage with a preset working power between the welding arc starting stage and the welding arc ending stage. The ring beam can play the role of stable preheating and slow cooling in the stable working stage, so as to increase the absorption rate of the welding base metal to the laser, improve the welding stability, delay the cooling speed of the weld seam, and reduce the local thermal stress of the weld seam , to avoid weld cracks.

In some embodiments, controlling the central beam to emit in the form of modulated pulses specifically includes: selecting at least one of pulse waves including triangle, corrugated, sawtooth, trapezoidal, and stepped beams as the central beam. The center power first rises to the highest point and then falls, because the center power reaches the highest point and breaks through the laser power threshold required to melt the welding base metal to form a keyhole, and the laser absorption rate of the welding base material increases, so the pulse wave of the center beam In the second half of the process, the power can be appropriately reduced to further reduce heat input.

The second aspect of the present application provides a laser welding device, the laser welding device includes a laser emitter, and the laser emitter is used to implement the laser welding method of the first aspect of the present application to a welding position.

The laser welding method provided in this embodiment uses a double-beam laser composed of a central beam and a ring beam for welding. The high-intensity laser of the center beam can play the role of melting and welding the base material. The ring beam is distributed around the center beam, and the ring beam The weak-intensity laser can not only play the role of preheating the welding base metal, but also can play the role of delaying the cooling speed of the weld, so as to reduce the phenomenon of crack defects in the metal material during the cooling process of laser welding, especially It can reduce the occurrence of crack defects in welds of dissimilar metal materials (such as steel and copper) during cooling.

In some embodiments, the laser welding equipment further includes a controller, the controller is provided with a computer-readable storage medium and a control device, and the control device includes: an acquisition module, used to acquire the weld seam type of the welding position; a selection module, used for Select a matching double-beam laser according to the type of weld; the control module is used to control the laser emitter to generate a central beam corresponding to the center point of the welding position according to the matched double-beam laser and to surround the central beam and communicate with it Ring beam with concentric center beam.

A third aspect of the present application provides a laser welding assembly welded by the laser welding equipment according to the second aspect of the present application.

In some embodiments, the laser welding assembly includes a steel copper welding assembly and an aluminum alloy welding assembly.

The above description is only an overview of the technical solution of the present application. In order to better understand the technical means of the present application, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable , the following specifically cites the specific implementation manner of the present application.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiment. The drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the application. Also, the same reference numerals are used to denote the same components throughout the drawings. In the attached picture:

Fig. 1 is the flow chart of the laser welding method of some embodiments of the present application;

Fig. 2 is the axonometric view of the double-beam laser of some embodiments of the present application;

Fig. 3 is the front view of the double-beam laser shown in Fig. 2;

Fig. 4 is a schematic diagram of the application of the double-beam laser shown in Fig. 2;

Fig. 5 is the schematic diagram of the central beam of double-beam laser shown in Fig. 2;

Fig. 6 is the schematic diagram of the annular beam of double-beam laser shown in Fig. 2;

Fig. 7 is a schematic diagram of the central beam of the first embodiment of the present application;

Fig. 8 is a schematic diagram of the central beam of the second embodiment of the present application;

Fig. 9 is a schematic diagram of the central beam of the third embodiment of the present application;

Fig. 10 is a schematic diagram of the central beam of the fourth embodiment of the present application;

Fig. 11 is a schematic diagram of the central beam of the fifth embodiment of the present application;

FIG. 12 is a schematic diagram of the ring beam of the first embodiment of the present application;

FIG. 13 is a schematic diagram of a ring beam according to the second embodiment of the present application;

FIG. 14 is a schematic diagram of a ring beam according to a third embodiment of the present application;

FIG. 15 is a schematic diagram of a ring beam according to a fourth embodiment of the present application;

FIG. 16 is a schematic diagram of a ring beam according to a fifth embodiment of the present application;

Fig. 17 is a schematic diagram of a ring beam according to the sixth embodiment of the present application;

Fig. 18 is a structural block diagram of a controller according to an embodiment of the present application;

Fig. 19 is an appearance view of the weld of the first embodiment of the present application;

Fig. 20 is the exterior view of weld seam of prior art;

Fig. 21 is an appearance view of the weld of the second embodiment of the present application.

Part of the reference numerals in the detailed description are as follows:

100 double-beam lasers; 10 center beams; 20 ring beams, 21 inner walls, 22 outer walls;

200 welding base metal, 210 base metal steel plate, 220 base metal copper plate;

300 controller, 310 computer readable storage medium, 320 control device, 321 acquisition module, 322 selection module, 323 control module.

Detailed ways

Embodiments of the technical solutions of the present application will be described in detail below in conjunction with the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and therefore are only examples, rather than limiting the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the application; the terms used herein are only for the purpose of describing specific embodiments, and are not intended to To limit this application; the terms "comprising" and "having" and any variations thereof in the specification and claims of this application and the description of the above drawings are intended to cover a non-exclusive inclusion.

In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects, and should not be understood as indicating or implying relative importance or implicitly indicating the number, specificity, or specificity of the indicated technical features. Sequence or primary-secondary relationship. In the description of the embodiments of the present application, "plurality" means two or more, unless otherwise specifically defined.

Reference herein to an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The occurrences of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is understood explicitly and implicitly by those skilled in the art that the embodiments described herein can be combined with other embodiments.

In the description of the embodiment of the present application, the term "and/or" is only a kind of association relationship describing associated objects, which means that there may be three kinds of relationships, such as A and/or B, which may mean: A exists alone, and A exists at the same time and B, there are three cases of B alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), similarly, "multiple groups" refers to more than two groups (including two), and "multiple pieces" refers to More than two pieces (including two pieces).

In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical" "Horizontal", "vertical", "parallel", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship as Based on the orientation or positional relationship shown in the drawings, it is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, therefore It should not be understood as a limitation to the embodiment of the present application.

In the description of the embodiments of this application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "connection" and "fixation" should be interpreted in a broad sense, for example, it can be a fixed connection or a fixed connection. Disassembled connection, or integration; it can also be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the embodiments of the present application according to specific situations.

The existing laser welding process assisted by arc synchronous preheating uses arc as the preheating heat source to alleviate the cracks in the welding base metal during the welding process, and effectively improve the disadvantages of low laser absorption rate of the welding base material and high energy consumption in the welding process. , improve the laser utilization. However, in addition to the control of laser welding process parameters, the welding process also needs to coordinate the control of arc current, shielding gas flow, welding torch inclination angle, distance between arc center and laser spot center, and there are many control parameters. Moreover, this welding process can only preheat the workpiece, and cannot play a slow cooling effect to delay the cooling rate of the weld seam. This welding process is also only suitable for V-shaped groove joints, and it needs to be filled with powder, and the newly formed material is used to connect the welding base metal, and it is not suitable for lap joints where the workpieces are distributed up and down. The laser welding method of the present application can play a slow cooling effect to delay the cooling rate of the weld seam, thereby reducing the risk of cracks at the weld seam.

The laser welding method of this application is suitable for the welding of steel-copper alloy components and aluminum alloy components, but not limited to the welding of steel-copper alloy components and aluminum alloy components. The laser welding method of this application is suitable for other same base metal workpieces and different base metal workpieces It can also be applied to the welding of V-groove joints and lap joints where the base metal is distributed up and down.

In some embodiments of the present application, as shown in FIGS. 1 to 3 , a laser welding method is provided. The laser welding method includes: obtaining the weld type of the welding position; selecting a matching double-beam laser 100 according to the weld type; According to the matched double-beam laser 100 , the laser emitter is controlled to generate a central beam 10 corresponding to the central point of the welding position and a ring-shaped beam 20 surrounding the periphery of the central beam 10 and concentric with the central beam 10 .

In this embodiment, the weld type includes the material of the weld base material 200 and the structure of the weld. Different weld base materials have different physical and chemical properties such as expansion coefficients. According to the physical and chemical properties such as the expansion coefficient of the weld base material Selecting a matching double-beam laser 100 , such as selecting the effective welding area and welding power of the double-beam laser 100 , can reduce the occurrence of cracks in the weld seam of the welding base material 200 under stress.

Different weld structures also need to match the dual-beam laser 100 with different sizes and powers. For example, V-groove joints and lap joints distributed up and down the welding base metal 200 need to select the effective welding area and welding power of the dual-beam laser 100 , can reduce the occurrence of cracks in the weld seam of the welding base metal 200 under stress.

As shown in Figure 4, the laser welding method provided by this embodiment uses a double-beam laser 100 composed of a central beam 10 and a ring beam 20 for welding, and the high-intensity laser of the central beam 10 can play the role of melting and welding the base material 200, The ring beam 20 is distributed around the central beam 10. The weak intensity laser of the ring beam 20 can not only preheat the welding base material 200, but also slow down the cooling rate of the weld seam, thereby reducing the amount of metal material. The phenomenon of crack defect formation during the cooling process of laser welding, especially the phenomenon of crack defect formation during the cooling process of welds of dissimilar metal materials (such as steel and copper) and lap joints can be reduced.

Further, since the central beam 10 and the ring beam 20 disclosed in the present application are set to be distributed concentrically, therefore, it is not necessary to coordinately control the emission angle of the center beam 10 and the ring beam 20 and the distance between the center beam 10 and the ring beam 20, so that the double beam The control parameters of the laser 100 are reduced. Compared with the prior art, the synchronous action of the central beam 10 and the ring beam 20 can not only play a role in slow cooling to delay the cooling speed of the weld, but also be applicable to V-groove joints And the lap joints distributed up and down the welding base metal 200.

In some embodiments, controlling the double-beam laser 100 to generate a central beam 10 corresponding to the central point of the welding position and a ring-shaped beam 20 surrounding the periphery of the central beam 10 and concentric with the central beam 10 specifically includes: controlling the central beam 10 It emits in the manner of modulated pulses, and/or controls the ring beam 20 to emit in the manner of continuous waves.

In this embodiment, the mode of modulated pulse transmission refers to the mode of pulse width modulation PWM (Pulse-widthmodulation) transmission, which is to reduce the average power delivered by the central beam 10 by dispersing the effective central beam 10 into discrete forms A mode of continuous wave emission means that the laser outputs the ring beam 20 in a continuous mode instead of a pulse mode, and the ring beam 20 is emitted by a sine wave and a continuous wave synthesized by several sine components.

Setting the central beam 10 as a modulated pulse laser can reduce the heat input of the central beam 10 and reduce the burning loss and evaporation of low melting point alloy elements; the continuous preheating of the ring beam 20 can increase the absorption of the laser by the welding base material 200 efficiency, improve welding stability, and can also clean the surface of the welding base metal 200 to volatilize low-melting point pollutants and reduce spatter caused by low-melting point pollutants. The continuous preheating of the ring beam 20 can also delay the cooling rate of the weld seam. Reduce the local thermal stress of the weld and avoid weld cracks.

As shown in FIG. 5 , in some embodiments, the central beam 10 includes a tapered cylindrical beam whose outer diameter gradually increases from high to low, and/or the annular beam 20 includes a tapered cylindrical beam whose outer diameter gradually increases from high to low. beam.

In this embodiment, the diameter of the central beam 10 gradually increases from high to low, and the outer wall surface 22 of the central beam 10 can be set as an oblique line, an inner concave arc surface or an outer convex arc surface, by setting the central beam 10 as a cone The columnar beam can increase the spot area of the central beam 10 acting on the welding base material 200, reduce the local heat input of the central beam 10 acting on the welding base material 200, and reduce the burning loss and evaporation of low melting point alloy elements. The larger spot size of the central beam 10 can also reduce the stirring effect of the keyhole on the molten pool during the welding process, avoid excessive mixing between dissimilar metals, thereby reducing cracks caused by different expansion coefficients during the cooling process of dissimilar metals.

The diameter of the ring beam 20 gradually increases from high to low, and the outer wall surface 22 of the ring beam 20 can be set as an oblique line, an inner concave arc surface or an outer convex arc surface. By setting the ring beam 20 as a tapered cylindrical beam, it can increase The annular beam 20 acts on the spot area on the welding base material 200, and continuously preheats, increases the laser absorption rate of the workpiece, improves welding stability, and can also clean the surface of the welding base material 200, so that low melting point pollutants can be volatilized, reducing the Splash caused by low melting point pollutants; it can also delay the cooling rate of the weld, reduce thermal stress, and avoid cracks.

As shown in FIG. 6 , in some embodiments, the tapered cylindrical light beam includes an inner wall surface 21 and an outer wall surface 22 distributed along the radial interval of the tapered cylindrical light beam, and the inner wall surface 21 and the outer wall surface 22 are formed along the height direction. The cross section is an inverted V-shaped structure.

In this embodiment, the inner wall surface 21 and the outer wall surface 22 can increase the spot area of the ring beam 20 projected on the welding base material 200, thereby increasing the effective area of the ring beam 20, and improving the preheating effect and slow cooling of the ring beam 20 It can reduce the occurrence of defects such as welding cracks in the welding base metal 200 during the welding process.

Further, the type of weld includes the base material of the weld, and selecting the matching double-beam laser 100 according to the type of the weld specifically includes: selecting the matching central beam 10 and ring beam 20 according to the base material of the weld. Different weld base metals have different physical and chemical properties such as expansion coefficients. According to the physical and chemical properties such as expansion coefficients of the weld base metal, the matching dual-beam laser 100 is selected, such as the effective welding area and welding power of the dual-beam laser 100, It can reduce the occurrence of cracks in the weld seam of the welding base material 200 under the action of stress.

In some embodiments, selecting the matching center beam 10 and ring beam 20 according to the weld type specifically includes: determining the spot diameter of the center beam 10 as d, and the spot diameter of the ring beam 20 as D according to the base material of the weld, where D and the ratio of d satisfies 2≤D/d≤10.

In this embodiment, the base material of the weld includes steel and copper, and D/d≥2 can ensure that the spot diameter of the ring beam 20 exceeds at least one time of the spot diameter of the center beam 10. Since the center beam 10 is concentric with the ring beam 20, Only the portion of the annular beam 20 whose diameter exceeds the central beam 10 can play the role of preheating and slow cooling, as well as the effect of cleaning the weld surface; D/d≤10 is to avoid the thermal impact caused by the excessive diameter of the annular beam 20 spot If the area range is too large, the grain coarsening in the welding area of the welding base metal 200 will affect the properties of the base metal.

In some embodiments, selecting the matching dual-beam laser 100 according to the weld type specifically includes: determining the spot diameter of the central beam 10 as d and the spot diameter of the ring beam 20 as D according to the base material of the weld, where D and d The ratio satisfies 3≤D/d≤8.

In this embodiment, the base metal of the weld includes aluminum alloy, and different base metals of the weld have different physical and chemical properties such as expansion coefficients. The application selects a dual-beam laser 100 with a matching size according to the physical and chemical properties such as the expansion coefficient of the aluminum alloy. , can reduce the occurrence of cracks in the weld seam of the welding base metal 200 under stress.

In some embodiments, selecting the matched dual-beam laser 100 according to the weld type specifically includes: determining the power of the central beam 10 as p and the power of the ring beam 20 as P according to the base material of the weld, wherein the ratio of P and p satisfies 1≤P/p≤6.

In this embodiment, the base material of the weld includes steel and copper, and P/p≥1 is because the spot diameter of the annular beam 20 is at least twice the spot diameter of the central beam 10, and the beam energy distribution of a general laser is Gaussian. , the middle energy is high, and the peripheral energy is low. If the energy (power) of the ring beam 20 is too low, the energy of the peripheral part corresponding to the ring beam 20 exceeding the diameter of the central beam 10 is lower, and the effect of preheating, slow cooling and cleaning the surface is achieved. Not significant; P/p≤6 is to avoid excessive heat input of the annular beam 20 , causing burning loss and evaporation of low-melting alloy elements.

In some embodiments, selecting the matched dual-beam laser 100 according to the weld type specifically includes: determining the power of the central beam 10 as p and the power of the ring beam 20 as P according to the base material of the weld, wherein the ratio of P and p satisfies 1≤P/p≤4.

In this embodiment, the weld base material includes aluminum alloy, and different weld base materials have different physical and chemical properties such as expansion coefficients. The application selects a dual-beam laser 100 with matching power according to the physical and chemical properties such as expansion coefficients of aluminum alloys. , can reduce the occurrence of cracks in the weld seam of the welding base metal 200 under stress.

As shown in FIGS. 7 to 11 , in some embodiments, controlling the central beam 10 to emit in the form of modulated pulses specifically includes: selecting the pulse wave to include at least one beam in a triangle, corrugated, zigzag, trapezoidal, and stepped as the central beam.

In this embodiment, the central power of the central beam 10 can be set to first rise to the highest point and then decrease, because after the central power reaches the highest point and breaks through the laser power threshold required for melting and welding the base metal 200 to form a keyhole, the welding base The absorption rate of the laser light by the material 200 is increased, therefore, the power can be appropriately reduced in the second half of the pulse wave of the central beam 10 to further reduce the heat input.

As shown in FIGS. 12 to 17 , in some embodiments, controlling the ring-shaped beam 20 to emit in a continuous wave specifically includes: controlling the power of the ring-shaped beam 20 to gradually increase to a preset working power during the welding arc initiation stage; and/or The power of the ring beam 20 is controlled to gradually decrease from the preset working power during the welding arc closing stage.

In this embodiment, the arc starting stage of welding refers to the initial stage of welding, and the arc closing stage of welding refers to the finishing stage of welding. Both the arc starting stage and the welding finishing stage will produce arc craters, and looseness, cracks, pores, Slag inclusion and other phenomena, in order to overcome arc crater defects, the embodiment of the present application adjusts the weld seam shape by controlling the power of the annular beam 20 . Specifically, in the welding arc starting stage, the power of the ring beam 20 can be gradually increased to the preset working power from low to high, so as to avoid the "matchhead" shape at the arc starting; in the welding arc ending stage, the ring beam 20 The power is gradually reduced, which can reduce the welding line energy density, the weld width gradually narrows, and the deep penetration holes gradually become shallow during the welding process, thereby improving the arc crater morphology at the arc end of the weld.

The embodiment of the present application proposes that the annular beam 20 rises slowly at the arc starting point to weaken the "match head" shape of the arc starting point of the weld seam, and slowly descends at the arc ending point to reduce the appearance of the weld seam at the arc ending point. The phenomenon of arc crater depression.

In some embodiments, controlling the ring-shaped beam 20 to emit in a continuous wave manner further includes: controlling the power of the ring-shaped beam 20 to form a stable working stage with a preset working power between the welding arc starting stage and the welding arc ending stage.

In this embodiment, the annular beam 20 can play the role of stable preheating and slow cooling in the stable working stage, so as to increase the absorption rate of the welding base metal 200 to the laser, improve the welding stability, and can also delay the cooling speed of the weld seam , reduce the local thermal stress of the weld and avoid weld cracks.

The second aspect of the present application provides a laser welding device, the laser welding device includes a laser emitter, and the laser emitter is used to implement the laser welding method of the first aspect of the present application to a welding position.

The laser welding method provided in this embodiment uses a double-beam laser 100 composed of a central beam 10 and a ring beam 20 for welding. The high-intensity laser of the center beam 10 can play the role of melting and welding the base material 200, and the ring beam 20 is distributed in the center Around the beam 10, the weak-intensity laser of the annular beam 20 can not only play the role of preheating the welding base material 200, but also can play the role of delaying the cooling speed of the weld seam, so as to reduce the cooling process of the metal material during laser welding. In particular, it can reduce the phenomenon of crack defects in the welding seam of dissimilar metal materials (such as steel and copper) and lap joints during cooling.

Further, since the central beam 10 and the ring beam 20 disclosed in the present application are set to be distributed concentrically, therefore, it is not necessary to coordinately control the emission angle of the center beam 10 and the ring beam 20 and the distance between the center beam 10 and the ring beam 20, so that the double beam The control parameters of the laser 100 are reduced. Compared with the prior art, the synchronous action of the central beam 10 and the ring beam 20 can not only play a role in slow cooling to delay the cooling speed of the weld, but also be applicable to V-groove joints And the lap joints distributed up and down the welding base metal 200.

As shown in FIG. 18, in some embodiments, the laser welding equipment further includes a controller 300, the controller 300 is provided with a computer-readable storage medium 310 and a control device 320, and the control device 320 includes: an acquisition module 321 for acquiring The weld seam type of the welding position; the selection module 322 is used to select the matching double-beam laser 100 according to the weld seam type; the control module 323 is used to control the center point of the laser emitter to generate and the welding position according to the matched double-beam laser Corresponding to the central beam 10 and the annular beam 20 surrounding the central beam 10 and concentric with the central beam 10 .

A third aspect of the present application provides a laser welding assembly welded by the laser welding equipment according to the second aspect of the present application.

The laser welding assembly provided in the embodiment of the present application is welded by the same metal material or dissimilar metal materials through the laser welding method of the first aspect of the application. The laser welding method of the first aspect of the application can reduce the weld pool. Generation of defects such as small cracks and pores. Especially for laser welding of dissimilar metal materials (such as steel and copper), the laser welding components can adapt to the difference in physical and chemical properties such as the expansion coefficient of the two metals during the welding process, reducing the laser welding components under different stresses in the weld. crack phenomenon.

In some embodiments, the laser welding assembly includes a steel copper welding assembly and an aluminum alloy welding assembly. As shown in FIG. 4 , FIG. 19 , FIG. 20 and FIG. 21 , the technical solution of the present application will be described in detail through two embodiments below.

Example 1: Steel Copper Welding

The base steel plate 210 and the base copper plate 220 are arranged vertically, the base steel plate 210 is on top, and the base copper plate 220 is on the bottom. The spot diameter of the center beam 10 of the double-beam laser 100 is 100 μm, the spot diameter of the ring beam 20 is 500 μm, the welding center power of the center beam 10 is 700w～1200w, the ring welding power of the ring beam 20 is 800w～1800w, and the welding speed is 100mm /s～200mm/s, the defocus range is 0～+10mm, the protective gas is nitrogen, and the flow rate is 15～30L/min. The waveform of the ring beam 20 is selected from the ring beam 20 of the third embodiment of the application in Figure 14, and the waveform of the center beam 10 is selected from the center beam 10 of the third embodiment of the application in Figure 9, and the waveform pulse width of the center beam 10 is 2ms～ 10ms. This process parameter results in a crack-free weld. The appearance of the weld obtained according to this method is shown in Figure 19 without cracks, while the appearance of the weld without using the central beam 10 of the modulated pulse and/or without the ring beam 20 of the continuous wave is shown in Figure 20, the weld at the There are obvious cracks.

Example 2: Steel Copper Welding

The base steel plate 210 and the base copper plate 220 are arranged vertically, the base steel plate 210 is on top, and the base copper plate 220 is on the bottom. The spot diameter of the center beam 10 of the double-beam laser 100 is 100 μm, the spot diameter of the ring beam 20 is 500 μm, the welding center power of the center beam 10 is 700w～1200w, the ring welding power of the ring beam 20 is 800w～1800w, and the welding speed is 100mm /s～200mm/s, the defocus range is 0～+10mm, the protective gas is nitrogen, and the flow rate is 15L/min～30L/min. The waveform of the ring beam 20 is selected from the ring beam 20 of the fourth embodiment of the application in Fig. 15, and the waveform of the center beam 10 is selected from the center beam 10 of the first embodiment of the application in Fig. 10ms. This process parameter can also get a crack-free weld. The appearance of the weld obtained according to this method is shown in Figure 21, without cracks.

It should be noted that the embodiments of the present application only illustrate the structures related to the invention on the laser welding equipment, and it does not mean that the laser welding equipment only has these structures, and other structures on the laser welding equipment will not be described here one by one. elaborate.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present application. All of them should be covered by the scope of the claims and description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims (13)

1. A laser welding method, characterized in that the laser welding method comprises:

acquiring the type of a welding seam at a welding position;

selecting matched double-beam laser according to the type of the welding seam;

and according to the matched double-beam laser, controlling a laser emitter to generate a central beam corresponding to the central point of the welding position and an annular beam which surrounds the periphery of the central beam and is concentric with the central beam.

2. The laser welding method according to claim 1, wherein the controlling the dual-beam laser to generate a central beam corresponding to a center point of the welding location and an annular beam that surrounds a periphery of the central beam and is concentric with the central beam specifically comprises:

controlling the central beam to be emitted in modulated pulses, and/or

Controlling the annular light beam to be emitted in a continuous wave mode.

3. The laser welding method of claim 1, wherein the central beam comprises a cone-shaped cylindrical beam with a gradually increasing outer diameter from high to low, and/or the annular beam comprises a cone-shaped cylindrical beam with a gradually increasing outer diameter from high to low.

4. The laser welding method according to claim 3, wherein the cone-shaped cylindrical beam includes an inner wall surface and an outer wall surface that are spaced apart from each other in a radial direction of the cone-shaped cylindrical beam, and a cross section of the inner wall surface and the outer wall surface formed in a height direction is an inverted V-shaped structure.

5. The laser welding method according to claim 1, wherein the selecting the matched central beam and annular beam according to the weld type comprises in particular:

determining the spot diameter of the central beam as D and the spot diameter of the annular beam as D according to the type of the welding seam,

wherein the ratio of D to D satisfies 2 ≤ D/D ≤ 10.

6. The laser welding method according to claim 1, wherein the selecting a matched dual-beam laser according to the weld type comprises in particular:

determining the power of the central beam to be P and the power of the annular beam to be P according to the welding seam type,

wherein the ratio of P to P satisfies 1. Ltoreq. P/P. Ltoreq.6.

7. The laser welding method according to claim 2, wherein said controlling said annular beam to be emitted in a continuous wave manner comprises in particular:

controlling the power of the annular light beam to gradually increase to a preset working power in a welding arc starting stage; and/or

And controlling the power of the annular light beam to be gradually reduced from the preset working power in the welding arc-extinguishing stage.

8. The laser welding method of claim 7, wherein the controlling the ring beam to be emitted in a continuous wave further comprises:

and controlling the power of the annular light beam to form a stable working stage of the preset working power between the welding arc starting stage and the welding arc receiving stage.

9. The laser welding method according to claim 2, wherein said controlling said central beam to emit in modulated pulses comprises in particular:

selecting at least one light beam of triangular, corrugated, sawtooth, trapezoid and step-shaped pulse wave as the central light beam.

10. A laser welding apparatus, characterized in that it comprises a laser emitter for implementing the laser welding method according to any one of claims 1 to 9 to a welding location.

11. The laser welding apparatus according to claim 10, further comprising a controller provided with a computer-readable storage medium and a control device, the control device including:

the acquisition module is used for acquiring the type of the welding seam at the welding position;

the selection module is used for selecting the matched double-beam laser according to the type of the welding seam;

and the control module is used for controlling the laser emitter to generate a central light beam corresponding to the central point of the welding position and an annular light beam which surrounds the periphery of the central light beam and is concentric with the central light beam according to the matched double-beam laser.

12. A laser welded assembly, characterized in that it is welded by a laser welding apparatus according to claim 10 or 11.

13. The laser welded assembly of claim 12, wherein the laser welded assembly comprises a steel braze welded assembly and an aluminum alloy weld assembly.

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