Laser welding device and method

Abstract

The invention relates to a laser welding device and method, and belongs to the technical field of welding engineering. The laser welding device comprises a workbench and a laser assembly, and the laser assembly comprises a fixing base, a telescopic arm and a laser. The workbench is configured to place a to-be-welded workpiece, and a first preset included angle is formed between the to-be-welded workpiece and the horizontal plane; the fixing base is installed on the workbench, one end of the telescopic arm is hinged to the fixing base, the other end of the telescopic arm is hinged to the laser, the laser is arranged above the to-be-welded workpiece, and a second preset included angle is formed between a laser beam emitted by the laser and the normal of the to-be-welded workpiece. By adjusting the first preset included angle and the second preset included angle of the to-be-welded workpiece, the downward flowing speed of molten pools on the front side, the left side and the right side of a small hole in the laser welding process is greatly decreased, the volume of the molten pools sprayed out from the bottom is greatly reduced, humps are prevented from being formed at the root of a welding seam, welding seam collapse is prevented, and the influence of the welding seam on the workpiece is reduced.

Description

Technical Field

[0001] The present application belongs to the field of welding engineering technology, and specifically relates to a laser welding device and method. Background Art

[0002] The current welding technology mainly consists of arc welding, gas shielded welding, laser welding, friction welding, etc. Among them, laser welding technology is the most widely used technology, which has the advantages of fast heating speed, small welding deformation, and high processing flexibility.

[0003] In the prior art, such as Figure 1 and Figure 2 As shown, two workpieces 100 to be welded are placed flat on a workbench, the laser is located on the top of the workpieces to be welded, and the laser beam acts vertically on the butt joint of the two workpieces 100 to be welded. When welding, the welding direction is +X, and the laser penetrates the butt joint of the two workpieces 100 to be welded, so that the welding plates at the butt joint are melted together, and the welding is completed after cooling and shaping.

[0004] In the above scheme, under the action of the laser beam, the surface of the joint sinks to form a keyhole (also called a small hole), and the reaction force F of the steam in the small hole 400 caused by the laser beam and the self-gravity G of the molten pool cause the molten pools on the front, left and right sides of the small hole 400 to flow downward along the hole wall, thereby forming a weld hump 900 at the root of the weld 600, causing the weld to collapse and affecting the welding effect. Summary of the invention

[0005] The present application provides a laser welding device and method, which are used to solve the problem in the prior art that when the workpieces to be welded are welded by laser welding technology, a weld hump is formed at the root of the weld due to the action of welding steam and gravity, causing the weld to collapse and affecting the welding effect.

[0006] In a first aspect, the present application provides a laser welding device, comprising a workpiece to be welded, a workbench, and a laser assembly, wherein the laser assembly comprises a fixed seat, a telescopic arm, and a laser;

[0007] The workpiece to be welded is configured to be arranged on the workbench, and a first preset angle is formed between the workpiece to be welded and the horizontal plane;

[0008] The fixing seat is installed on the workbench, one end of the telescopic arm is hinged to the fixing seat, the other end of the telescopic arm is hinged to the laser, the workpiece to be welded is located below the laser, and the laser is rotated so that a second preset angle exists between the laser and the normal line of the workpiece to be welded.

[0009] In the embodiment provided in the present application, a positioning assembly is also included, and the positioning assembly includes a base, a cylinder, a positioning plate and a clamping plate;

[0010] The base and the cylinder are both arranged on the workbench, one end of the positioning plate is hinged to the base, and one end of the positioning plate away from the fixing seat is hinged to the cylinder, the positioning plate is used to mount the workpiece to be welded, and the first preset angle between the workpiece to be welded and the workbench is adjusted by adjusting the extension and contraction of the cylinder;

[0011] In the embodiment provided in the present application, a jet assembly is also included, and the jet assembly includes a gas tank and a nozzle connected to the gas tank. The gas tank is installed on the workbench, and the nozzle is installed on the laser.

[0012] In the embodiment provided in the present application, the first preset angle is 10-90 degrees, the second preset angle is 5-45 degrees, and the sum of the first preset angle and the second preset angle is greater than 90 degrees.

[0013] In a second aspect, the present application further provides a laser welding method, which is applied to the laser welding device described in the first aspect, comprising the following steps:

[0014] Mounting two workpieces to be welded on a workbench, with a first preset angle between the two workpieces to be welded and the horizontal plane;

[0015] The laser of the laser welding device is controlled to emit a laser beam, and the two workpieces to be welded are welded by the laser beam, wherein a second preset angle is formed between the laser beam and the normal lines of the two workpieces to be welded.

[0016] In the embodiment provided in the present application, the step of installing two workpieces to be welded on a workbench includes:

[0017] The two workpieces to be welded are placed flat on the table top of the workbench, the table top is an inclined surface and has the first preset angle with the horizontal plane, wherein the first preset angle is 10-90 degrees.

[0018] In the embodiment provided in the present application, the step of installing two workpieces to be welded on a workbench includes:

[0019] The workbench is provided with a positioning component, and the two workpieces to be welded are mounted on the positioning component. The positioning component enables a first preset angle to exist between the workpieces to be welded and the horizontal plane, wherein the first preset angle is 10-90 degrees.

[0020] In the embodiment provided in the present application, the controlling the laser beam to weld the two workpieces to be welded comprises:

[0021] Welding the two workpieces to be welded by controlling the welding power, welding speed, defocusing amount and swing amplitude of the laser beam;

[0022] Among them, the welding power is 1-2kW, the welding speed is 1-2m / min, the defocus amount is 0-5mm, and the swing amplitude is 0-2mm.

[0023] In the embodiment provided in the present application, the second preset angle is 5-45 degrees, the sum of the first preset angle and the second preset angle is greater than 90 degrees, and the sum of the first preset angle and the second preset angle is greater than 90 degrees.

[0024] In the embodiment provided in the present application, the controlling the laser beam to weld the two workpieces to be welded comprises:

[0025] When the laser beam is controlled to weld the two workpieces to be welded, a protective gas is blown to the workpieces to be welded during welding.

[0026] In a laser welding device and method provided by the present application, a laser welding device provided by the present application includes a workbench and a laser assembly, and the laser assembly includes a fixed seat, a telescopic arm and a laser. The workbench is configured to place a workpiece to be welded, and to make a first preset angle between the workpiece to be welded and the horizontal plane. The fixed seat is installed on the workbench, one end of the telescopic arm is hinged to the fixed seat, and the other end of the telescopic arm is hinged to the laser, and the laser is arranged above the workpiece to be welded, and a second preset angle is formed between the laser beam emitted by the laser and the normal of the workpiece to be welded. By adjusting the workpiece to be welded so that it has a first preset angle with the workbench, and adjusting the laser beam so that it has a second preset angle with the normal of the workpiece to be welded, the combined force of the laser beam acting on the front side and the left and right sides of the small hole of the workpiece to be welded is reduced, and then the downward flow speed of the molten pool on the front side and the left and right sides of the small hole is greatly slowed down, and the volume of the molten pool ejected from the bottom is greatly reduced, thereby avoiding the formation of a hump at the root of the weld, preventing the weld from collapsing, and reducing the impact of the weld on the workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0028] Figure 1 This is an effect diagram of the weld seam collapse caused by laser welding of a workpiece in the prior art;

[0029] Figure 2 for Figure 1 The effect diagram of the weld seam collapse of the workpiece at another angle;

[0030] Figure 3 This is a schematic diagram of the structure of the laser welding device proposed in this application;

[0031] Figure 4 for Figure 3 A top view of the laser welding device without the laser assembly and the jet assembly;

[0032] Figure 5 A flow chart of the laser welding method proposed in this application;

[0033] Figure 6 A schematic diagram of the structure of a workpiece to be welded using the laser welding method of the present application;

[0034] Figure 7 for Figure 6 A schematic diagram of the structure of the workpiece to be welded at another angle;

[0035] Figure 8 This is a cross-sectional view of a weld obtained by the laser welding method of the present application.

[0036] Reference numerals:

[0037] 100-workpiece to be welded;

[0038] 200-Laser beam;

[0039] 300-nozzle;

[0040] 400-small hole;

[0041] 500-parent material;

[0042] 600-weld;

[0043] 700-front molten pool;

[0044] 800-rear molten pool;

[0045] 900-weld hump;

[0046] 1000- workbench;

[0047] 1100-laser assembly; 1110-fixed seat; 1120-telescopic arm; 1130-laser;

[0048] 1200-positioning assembly; 1210-base; 1220-cylinder; 1230-positioning plate; 1240-clamping plate; 1250-through hole;

[0049] 1300-jet assembly; 1310-gas tank.

[0050] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0052] The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein, for example, can be implemented in an order other than those illustrated or described herein.

[0053] In the embodiments of the present application, the words "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0054] In the description of the embodiments of the present application, it should be understood that the terms "inside", "outside", "top", "bottom", "front", "back", etc. indicating the orientation or position relationship (if any) are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0055] The current welding technology mainly consists of arc welding, gas shielded welding, laser welding, friction welding, etc. Among them, laser welding technology is the most widely used technology, which has the advantages of fast heating speed, small welding deformation, and high processing flexibility.

[0056] For the welding method in the prior art, such as Figure 1 and Figure 2 As shown, Figure 1 This is an effect diagram of the weld seam collapse caused by laser welding of a workpiece in the prior art; Figure 2 for Figure 1 Another angled rendering of the weld collapse of the workpiece.

[0057] In the prior art, in order to flat-weld two workpieces 100 to be welded together, the two workpieces 100 to be welded are usually butt-jointed and placed flat on a workbench 1000 , and laser welding is performed on the butt joints, thereby completing the welding of the two workpieces 100 to be welded.

[0058] In this method, the welding direction is Figure 1 In the +X direction, the laser beam 200 melts the base material 500 to form a molten pool, which sinks to form a small hole 400. The molten pool at the front end of the small hole 400 is the front molten pool 700, and the molten pool at the rear end of the small hole 400 is the rear molten pool 800. The flow direction of the molten pool is the +Y direction. Due to the effect of the laser beam 200 (the energy of the laser beam 200 will not penetrate the bottom of the weld 600), the front molten pool 700 and the molten pools on the left and right sides flow downward under the action of gravity. The molten pool flowing to the bottom will flow backward and form a rear molten pool 800. After the rear molten pool 800 is cooled, the weld 600 is formed, and the welding is completed.

[0059] However, in the above technical solution, when the molten pool flows to the bottom of the small hole 400, it will sink downward under the action of the molten pool's own gravity G and the reaction force F of the steam in the small hole 400, thereby forming a weld hump 900 at the root of the weld 600, causing the weld 600 to collapse and affecting the use of the welded part.

[0060] In summary, the present application proposes a laser welding device and method to solve the problem in the prior art that when the workpieces to be welded are welded by laser welding technology, a weld hump 900 is formed at the root of the weld 600 due to the action of welding steam and gravity, causing the weld 600 to collapse and affecting the welding effect. The present application will be described in detail below in conjunction with the accompanying drawings.

[0061] in, Figure 3 This is a schematic diagram of the structure of the laser welding device proposed in this application; Figure 4 for Figure 3 A top view of the laser welding device without the laser assembly and the jet assembly; Figure 5 A flow chart of the laser welding method proposed in this application; Figure 6 A schematic diagram of the structure of a workpiece to be welded using the laser welding method of the present application; Figure 7 for Figure 6 A schematic diagram of the structure of the workpiece to be welded at another angle; Figure 8 This is a cross-sectional view of a weld obtained by the laser welding method of the present application.

[0062] In the above schematic diagram, F is the reaction force of the steam of the laser beam 200 on the molten pool, G is the gravity of the molten pool, α is the first preset angle, β is the second preset angle, +X is the moving direction of the laser beam 200, and +Y is the flow direction of the molten pool. is the distance between the top of the weld 600 and the upper surface of the workpiece 100 to be welded, It is the distance between the bottom of the weld 600 and the upper surface of the workpiece 100 to be welded.

[0063] like Figure 3 , Figure 4 and Figure 6 As shown, the present application also provides a laser welding device, including a workbench 1000 and a laser assembly 1100 , wherein the laser assembly 1100 includes a fixing seat 1110 , a telescopic arm 1120 and a laser 1130 .

[0064] The workbench 1000 is configured to place a workpiece 100 to be welded, and to make a first preset angle between the workpiece 100 to be welded and a horizontal plane.

[0065] The fixed seat 1110 is installed on the workbench 1000, one end of the telescopic arm 1120 is hinged to the fixed seat 1110, and the other end of the telescopic arm 1120 is hinged to the laser 1130. The laser 1130 is arranged above the workpiece 100 to be welded, and there is a second preset angle between the laser beam 200 emitted by the laser 1130 and the normal of the workpiece 100 to be welded.

[0066] By adjusting the workpiece 100 to be welded so that it has a first preset angle with the workbench 1000, and adjusting the laser 1130 so that it has a second preset angle with the normal of the workpiece 100 to be welded, the resultant force of the laser 1130 acting on the molten pools on the front side and left and right sides of the small hole 400 of the workpiece 100 to be welded is reduced, and thus the downward flow speed of the molten pools on the front side and left and right sides of the small hole 400 is greatly slowed down, and the volume of the molten pool ejected from the bottom is greatly reduced, thereby avoiding the formation of a hump at the root of the weld 600, preventing the weld from collapsing, and reducing the impact of the weld on the workpiece.

[0067] The first preset angle is set to 10-90 degrees, the second preset angle is set to 5-45 degrees, and the sum of the first preset angle and the second preset angle is greater than 90 degrees.

[0068] The laser welding device further includes a positioning assembly 1200 , which includes a base 1210 , a cylinder 1220 , a positioning plate 1230 and a clamping plate 1240 .

[0069] The base 1210 and the cylinder 1220 are both arranged on the workbench 1000, one end of the positioning plate 1230 is hinged to the base 1210, and the end of the positioning plate 1230 away from the fixed seat 1110 is hinged to the cylinder 1220, and the workpiece 100 to be welded is installed on the positioning plate 1230. The first preset angle between the workpiece 100 to be welded and the workbench 1000 is adjusted by adjusting the extension and contraction of the cylinder 1220.

[0070] The above-mentioned laser welding device adopts a mounting positioning assembly 1200 to rotate the workpiece 100 to be welded, so that there is a first preset angle between the workpiece 100 to be welded and the horizontal plane.

[0071] Among them, the workpieces 100 to be welded are two flat plates with a thickness of 3 mm. The two workpieces 100 to be welded are placed flat on the positioning plate 1230 and butt-jointed together. The clamping plate 1240 is installed on the top of the two workpieces 100 to be welded. The bolts pass through the through holes 1250 on the clamping plate 1240 and are connected to the blind holes (not shown in the figure) on the workbench 1000 to fix the workpieces 100 to be welded.

[0072] Since the clamping plate 1240 in the above technical solution only needs to clamp a portion of the workpiece 100 to be welded, it can be applicable to workpieces 100 to be welded of different sizes.

[0073] The cylinder 1220 located at the bottom of the positioning plate 1230 can be extended and retracted to rotate the positioning plate 1230 around the base 1210 , and the inclination angle of the positioning plate 1230 is a first preset angle of the workpiece 100 to be welded.

[0074] It should be noted that in order to prevent the positioning plate 1230 from affecting the weld 600 of the workpiece 100 to be welded, an avoidance groove is provided in the middle of the positioning plate 1230 , and the avoidance groove is located at the bottom of the butt joint of the two workpieces 100 to be welded.

[0075] The laser assembly 1100 is installed next to the positioning assembly 1200. The height of the fixed base 1110 is higher than the height of the base 1210. The telescopic arm 1120 installed on the base 1210 can rotate along the base 1210, and the rotation direction is toward the workpiece 100 to be welded. A laser 1130 is arranged at one end of the telescopic arm 1120 away from the base 1210. The laser 1130 can rotate along the telescopic arm 1120, and the rotation direction of the laser 1130 is also toward the workpiece 100 to be welded.

[0076] In the embodiment provided in the present application, a jet assembly 1300 is also included. The jet assembly 1300 includes a gas tank 1310 and a nozzle 300 connected to the gas tank 1310 . The gas tank 1310 is installed on the workbench 1000 , and the nozzle 300 is installed on the laser 1130 .

[0077] The gas storage tank 1310 and the nozzle 300 are connected via a gas delivery pipe.

[0078] Combined with Figure 5 and Figure 6 As shown, a laser welding method provided by the present application comprises the following steps:

[0079] S101, two workpieces 100 to be welded are mounted on a workbench 1000, and a first preset angle is formed between the two workpieces 100 to be welded and a horizontal plane.

[0080] S102 , controlling the laser beam 200 to weld the two workpieces 100 to be welded, wherein a second preset angle is formed between the laser beam 200 and the two workpieces 100 to be welded.

[0081] In the above two steps, the workpiece 100 to be welded is adjusted to have a first preset angle with the workbench 1000, and the laser beam 200 is adjusted to have a second preset angle with the workpiece 100 to be welded, so that the combined force of the laser beam 200 acting on the molten pool on the front side and left and right sides of the small hole 400 of the workpiece 100 to be welded is reduced, and then the downward flow speed of the molten pool on the front side and left and right sides of the small hole 400 is greatly slowed down, and the volume of the molten pool ejected from the bottom is greatly reduced, thereby avoiding the formation of a weld hump 900 at the root of the weld 600, preventing the weld 600 from collapsing, and reducing the impact of the weld 600 on the workpiece.

[0082] The workbench 1000 may be a fixed welding workbench 1000, a mobile welding workbench 1000, a rotary welding workbench 1000, a lifting welding workbench 1000, and a multifunctional swing-arm welding workbench 1000, which may be set according to actual operation requirements.

[0083] The laser beam 200 may be a carbon dioxide laser beam 200 , a solid laser beam 200 , a carbon monoxide laser beam 200 , or a fiber laser beam 200 .

[0084] In the embodiment provided in the present application, an organic solvent is used to remove impurities on the upper and lower surfaces and the butt end faces of the base material 500 before welding the workpiece 100 to prevent the impurities from affecting the welding effect. The thickness of the workpiece 100 to be welded is 0.5-3 mm.

[0085] like Figure 6 and Figure 7 As shown, in the embodiment provided in the present application, two workpieces 100 to be welded are installed on a workbench 1000, including: placing the two workpieces 100 to be welded flat on the table top of the workbench 1000, the table top is an inclined surface and has a first preset angle with the horizontal plane, wherein the first preset angle is 10 degrees-90 degrees.

[0086] In the above technical solution, two workpieces 100 to be welded are placed flat on a workbench 1000 with an inclined surface so that a first preset angle (such as Figure 6 α angle in the image).

[0087] Recombination Figure 3 and Figure 6As shown, in other embodiments, two workpieces 100 to be welded are mounted on a workbench 1000, including: a positioning assembly 1200 is provided on the workbench 1000, the two workpieces 100 to be welded are mounted on the positioning assembly 1200, and there is a first preset angle between the positioning assembly 1200 and the horizontal plane, and the first preset angle is 10-90 degrees.

[0088] In the above technical solution, a rotatable positioning assembly 1200 is arranged on the workbench 1000, so that the two workpieces to be welded 100 placed on the positioning assembly 1200 have a first preset angle (such as Figure 6 α angle in the image).

[0089] Whether a workbench 1000 with an inclined surface or a workbench 1000 with a positioning assembly 1200 is used, welding is performed by tilting the workpiece 100 to be welded, and the first preset angle can be adjusted between 10 degrees and 90 degrees.

[0090] In the embodiment provided in the present application, controlling the laser beam 200 to weld two workpieces 100 to be welded includes: welding the two workpieces 100 to be welded by controlling the welding power, welding speed, defocusing amount and swing amplitude of the laser beam 200 .

[0091] Among them, the welding power is 1-2kW, the welding speed is 1-2m / min, the defocus is 0-5mm, and the swing amplitude is 0-2mm.

[0092] During the laser welding process of this embodiment, the first preset angle, the second preset angle, the welding power, the welding speed, the defocus amount and the swing amplitude will all affect the flow of the molten pool of the weld 600.

[0093] like Figure 6 and Figure 7 As shown, when the workpiece 100 to be welded forms a first preset angle with the horizontal plane, under the influence of gravity, the rear molten pool 800 of the small hole 400 will flow in the opposite direction of welding. Since the energy of the laser spot conforms to the Gaussian distribution, the energy density in the center of the laser spot is higher, so the temperature in the middle of the rear molten pool 800 of the small hole 400 is higher, and the temperature on both sides of the molten pool is lower, resulting in the molten metal on both sides of the rear molten pool 800 of the small hole 400 being easier to solidify. As the laser beam 200 advances forward, the molten metal is continuously replenished backward, resulting in the molten metal on both sides of the rear molten pool of the small hole 400 can only flow into the middle of the rear molten pool 800 of the small hole 400, thereby forming a weld 600 that is slightly convex in the middle and slightly concave on both sides.

[0094] When the first preset angle is larger, the gravity has a greater effect on the rear molten pool 800 of the small hole 400, the flow rate of the molten metal in the middle of the rear molten pool 800 of the small hole 400 is accelerated, and the molten metal on both sides of the rear molten pool 8 of the small hole 400 will also accelerate to flow to the middle, resulting in and Make it bigger, on the contrary and Become smaller.

[0095] When the welding power increases, the welding speed decreases, and the defocusing amount decreases, the heat input of the molten pool increases, and more molten base material 500 is contained in the molten pool, which results in a larger gravity of the rear molten pool 800 of the small hole 400, and also accelerates the flow speed of the molten metal on both sides of the rear molten pool 800 of the small hole 400 toward the middle, resulting in and Make it bigger, on the contrary and Become smaller.

[0096] To sum up, the first preset angle, welding power, welding speed, defocus and swing amplitude will all affect the weld 600. Therefore, by adjusting the above parameters, the first preset angle, welding power, welding speed, defocus and swing amplitude can be coordinated and optimized with each other, which can effectively avoid the collapse of the weld 600.

[0097] In other embodiments provided in the present application, a second preset angle is further provided, wherein the second preset angle is 5 degrees to 45 degrees.

[0098] It should be noted that the first preset angle and the second preset angle can be freely combined within the applicable angle variation range according to the different materials and thicknesses of the workpieces 100 to be welded.

[0099] In the embodiment provided in the present application, when the workpiece 100 to be welded forms a first preset angle with the plane and a second preset angle is formed between the center line of the laser beam 200 and the normal of the workpiece 100 to be welded, the force of gravity on the front molten pool 700 and the molten pools on the left and right sides of the small hole 400 is further reduced.

[0100] When the sum of the first preset angle and the second preset angle is greater than 90°, the direction of the component force of gravity and the direction of the reaction force of the steam in the small hole 400 on the molten pool are opposite, which can offset the downward effect of the reaction force of the steam in the small hole 400 on the molten pool to a certain extent, so that the resultant force acting on the front molten pool 700 of the small hole 400 and the molten pools on the left and right sides is reduced, and the downward flow speed of the front molten pool 700 and the molten pools on the left and right sides of the small hole 400 is greatly slowed down, and the volume of the molten pool ejected from the bottom is greatly reduced, thereby avoiding the formation of a weld hump 900 at the root of the weld 600, further preventing the collapse of the weld 600.

[0101] In summary, the change of the second preset angle will also affect the collapse degree of the root of the weld 600, and will also affect the side and Therefore, by changing the angle value of the first preset angle, the angle value of the second preset angle, the welding power, the welding speed, and the defocusing amount can be controlled. and The size of Figure 8 The weld 600 morphology is shown.

[0102] A large number of process experiments have proved that when the laser welding method provided in this application is used to weld 0.5-3mm plates, the first preset angle is set to 10-90 degrees, the second preset angle is set to 5-45 degrees, and the sum of the first preset angle and the second preset angle is greater than 90 degrees, the welding speed is set to 1-2m / min, the defocus is set to 0-5mm, the swing amplitude is set to 0-2mm, and the welding power is set to 1-2kW. After adjusting the above parameters, it can be ensured that the weld 600 in ≤0.08mm, ≤0.1mm, so as to reduce the height difference of the upper surface of the weld 600, improve the welding effect, and avoid the collapse of the weld 600 affecting the subsequent processing of the workpiece.

[0103] In the embodiment provided in the present application, a shielding gas is blown to the workpiece 100 to be welded, so as to prevent the focusing lens in the laser welding machine from being contaminated by metal vapor and splashed by liquid droplets, and to prevent the shielding gas from being oxidized during the workpiece welding process.

[0104] Among them, the shielding gas can be selected according to the welding material, and the main types are argon, nitrogen and helium.

[0105] In the embodiment provided in the present application, the shielding gas used is argon gas with a content of 99.999%. Argon gas has low activity and almost no chemical reaction with common metals. It is cheap and has high density, and can effectively protect the weld 600.

[0106] The gas flow rate of argon is 10-20 L / min.

[0107] The laser welding method provided in this application uses the above-mentioned device to operate in the following steps:

[0108] Step 1: Provide two workpieces 100 to be welded with a thickness of 0.5-3 mm and position them on the positioning plate 1230, and adjust the inclination angle of the positioning plate 1230 so that the workpieces 100 to be welded have a first preset angle with the horizontal surface. Before positioning, an organic flux can be used to remove impurities on the upper and lower surfaces and the butt end faces of the workpieces 100 to be welded.

[0109] Step 2: Control the laser assembly 1100 for welding, first rotate the laser 1130 to form a second preset angle between the center line of the laser beam 200 and the normal of the workpiece 100 to be welded, then adjust the welding power of the laser 1130, adjust the telescopic speed of the telescopic arm 1120 to determine the welding speed, adjust the rotation amplitude of the telescopic arm 1120 to determine the laser welding defocus amount, and determine the welding swing amplitude through the telescopic swing amplitude of the telescopic arm 1120 itself.

[0110] Step 3: Start the laser 1130, and the jet assembly 1300 blows the protective gas at the same time. The welding joint of the laser 1130 emits a laser beam 200 along the +X direction to radiate the joint between the two workpieces 100 to be welded, so as to realize laser welding.

[0111] Step 4: When the end point of the joint is reached, turn off the laser welding system, stop blowing the shielding gas, and complete the welding process.

[0112] The laser welding device proposed in the present application can realize workpieces of different sizes to be welded, and the first preset angle and the second preset angle can be freely adjusted to meet the welding requirements of different types of workpieces to be welded.

[0113] In summary, the laser welding device and method provided by the present application make the workpiece to be welded form a first preset angle with the horizontal plane, and the center line of the laser beam and the normal of the workpiece to be welded form a second preset angle, so that the resultant force acting on the molten pools on the front side and the left and right sides of the small hole is reduced, and then the downward flow speed of the molten pools on the front side and the left and right sides of the small hole is greatly slowed down, and the volume of the molten pool ejected from the bottom is greatly reduced, thereby obtaining a weld that is slightly convex in the middle and slightly concave on both sides, avoiding the formation of a weld hump at the root of the weld and preventing weld collapse.

[0114] The present application also provides a laser welding method in which a first preset angle is formed between the workpiece to be welded and the horizontal plane, so that the molten metal in the rear molten pool of the small hole will not flow back under the action of gravity and will not disturb the rear wall of the small hole, thereby improving the stability of the small hole and avoiding welding defects such as spatter.

[0115] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments, and the above embodiments are only used to illustrate the technical solution of the present application rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A laser welding device, characterized in that: It includes a workbench and a laser assembly, wherein the laser assembly includes a fixed seat, a telescopic arm and a laser; The workbench is configured to place a workpiece to be welded, and to make a first preset angle between the workpiece to be welded and a horizontal plane; The fixing seat is installed on the workbench, one end of the telescopic arm is hinged to the fixing seat, the other end of the telescopic arm is hinged to the laser, the laser is arranged above the workpiece to be welded, and a second preset angle is formed between the laser beam emitted by the laser and the normal line of the workpiece to be welded.

2. The laser welding device according to claim 1, characterized in that: Also included is a positioning assembly, which includes a base, a cylinder, a positioning plate and a clamping plate; The base and the cylinder are both arranged on the workbench, one end of the positioning plate is hinged to the base, and the end of the positioning plate away from the fixed seat is hinged to the cylinder. The positioning plate is used to mount the workpiece to be welded, and the first preset angle between the workpiece to be welded and the workbench is adjusted by adjusting the extension and contraction of the cylinder.

3. The laser welding device according to claim 2, characterized in that: It also includes a jet assembly, which includes a gas storage tank and a nozzle connected to the gas storage tank. The gas storage tank is installed on the workbench, and the nozzle is installed on the laser.

4. The laser welding device according to any one of claims 1 to 3, characterized in that: The first preset angle is 10-90 degrees, the second preset angle is 5-45 degrees, and the sum of the first preset angle and the second preset angle is greater than 90 degrees.

5. A laser welding method, characterized in that: The laser welding device according to any one of claims 1 to 4 comprises the following steps: Mounting two workpieces to be welded on a workbench of the laser welding device, with a first preset angle between the two workpieces to be welded and a horizontal plane; The laser of the laser welding device is controlled to emit a laser beam, and the two workpieces to be welded are welded by the laser beam, wherein a second preset angle is formed between the laser beam and the normal lines of the two workpieces to be welded.

6. The laser welding method according to claim 5, characterized in that: The step of mounting two workpieces to be welded on a workbench of the laser welding device comprises: The two workpieces to be welded are placed flat on the table top of the workbench, the table top is an inclined surface and has the first preset angle with the horizontal plane, wherein the first preset angle is 10-90 degrees.

7. The laser welding method according to claim 5, characterized in that: The step of mounting two workpieces to be welded on a workbench of the laser welding device comprises: The two workpieces to be welded are mounted on a positioning assembly of the laser welding device, and a first preset angle is formed between the positioning assembly and the horizontal plane, wherein the first preset angle is 10-90 degrees.

8. The laser welding method according to claim 6 or 7, characterized in that: The method of welding the two workpieces to be welded by using a laser beam comprises: Controlling the welding power, welding speed, defocusing amount and swing amplitude of the laser beam to weld the two workpieces to be welded; Among them, the welding power is 1-2kW, the welding speed is 1-2m / min, the defocus amount is 0-5mm, and the swing amplitude is 0-2mm.

9. The laser welding method according to claim 8, characterized in that: The second preset angle is 5-45 degrees, the sum of the first preset angle and the second preset angle is greater than 90 degrees, and the sum of the first preset angle and the second preset angle is greater than 90 degrees.

10. The laser welding method according to claim 5, characterized in that: The method of welding the two workpieces to be welded by using a laser beam comprises: When the two workpieces to be welded are welded by the laser beam, a protective gas is blown to the workpieces to be welded during welding.

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