A laser additive parts welding device and method with precise energy control

Abstract

The present invention discloses a laser additive welding device and method with precise energy control, belonging to the technical field of laser additive welding. The optical system of the laser additive welding device with precise energy control includes an annular light optical system and a point light optical system, and the point laser spot is located inside the annular laser spot; the visual temperature sensing system includes a CCD camera and a temperature sensor, and the CCD camera is used to monitor the morphology of the molten pool; the temperature sensor is arranged on the nozzle, and is used to monitor the temperature at the position to be welded; the control system adjusts the parameters of the optical system according to the morphology of the molten pool monitored by the CCD camera and the temperature monitored by the temperature sensor. The laser additive welding device and method with precise energy control described in the present invention are used to adjust the power and welding speed of the laser through real-time feedback of the temperature and molten pool morphology, thereby improving the welding quality between the laser selectively melted parts and the laser directly deposited parts.

Description

Technical Field

[0001] The present invention relates to the technical field of laser additive manufacturing welding, and in particular to a laser additive manufacturing welding device and method with precise energy control. Background Art

[0002] Laser additive manufacturing technology, also known as laser 3D printing technology, is a laser manufacturing technology that uses computer-aided processing to slice three-dimensional solid models into two-dimensional layers, which are then discretized into one-dimensional lines, and then deposited point by point using laser cladding technology to finally achieve the formation of three-dimensional solid parts. Compared with traditional manufacturing technology, this technology has the characteristics of flexibility, easy to realize intelligentization, short production cycle, and the ability to produce parts with very high mechanical properties. This technology has been widely used in aviation, national defense, transportation, energy, metallurgy, mining and other fields, and has shown attractive prospects.

[0003] The integrated manufacturing technology of "laser additive-welding" can effectively combine the advantages of laser selective melting (SLM), laser direct deposition (LMD), and laser welding, improve the designability of the structure, reduce stress concentration, and reduce fatigue weak areas, and can be used for rapid integrated manufacturing of complex structures. The performance of the welds of laser selective melting (SLM) parts and laser direct deposition (LMD) parts deteriorates due to the differences in structure and asymmetry of the weld structure, which affects the quality of welding between laser selective melting (SLM) parts and laser direct deposition (LMD) parts. Summary of the invention

[0004] The purpose of the present invention is to provide a laser additive welding device and method with precise energy control, which can adjust the power and welding speed of the laser through real-time temperature and molten pool morphology feedback, thereby improving the welding quality between laser selectively melted parts and laser directly deposited parts.

[0005] To achieve the above-mentioned purpose, the present invention provides a laser additive welding device with precise energy control, comprising:

[0006] An optical system, the optical system includes a ring light optical system for forming an outer ring laser spot and a point light optical system for forming a point laser spot, wherein the point laser spot is located inside the ring laser spot and is used to provide heating energy;

[0007] Visual temperature sensing system, the visual temperature sensing system includes a CCD camera and a temperature sensor. The CCD camera is used to provide a field of view at the welding position and monitor the morphology of the molten pool; the temperature sensor is set on the nozzle, and the nozzle is fixed at the bottom of the optical system to monitor the temperature at the position to be welded;

[0008] The control system adjusts the parameters of the optical system according to the molten pool morphology monitored by the CCD camera and the temperature monitored by the temperature sensor. The optical system, the CCD camera and the temperature sensor are all electrically connected to the control system.

[0009] Preferably, the annular light optical system includes a first laser, a first plane lens is arranged below the first laser, a first flat top light shaping mirror and a second flat top light shaping mirror are arranged below the first plane lens, the laser emitted by the first laser passes through the first plane lens and then through the first flat top light shaping mirror and the second flat top light shaping mirror to be arranged into parallel light, a conical reflector is arranged directly below the second flat top light shaping mirror, the conical reflector reflects the parallel light to both sides, an annular reflector is arranged outside the conical reflector, a half reflector is arranged directly below the conical reflector, the laser is reflected to the half reflector by the annular reflector, and a ring-shaped laser spot is formed by the half reflector.

[0010] Preferably, the point light optical system includes a second laser, a second plane lens is arranged below the second laser, a first collimating lens is arranged below the second plane lens, an inclined first reflecting lens is arranged below the first collimating lens, an X-direction galvanometer is arranged on one side of the first reflecting lens, the laser passes through the first plane lens and the first collimating lens and is reflected to the X-direction galvanometer by the first reflecting lens, the X-direction galvanometer provides X-direction laser swing, a Y-direction galvanometer is arranged below one side of the X-direction galvanometer, the laser enters the Y-direction galvanometer after being reflected by the X-direction galvanometer, the Y-direction galvanometer provides Y-direction laser swing, a second reflecting lens is arranged below the Y-direction galvanometer, a third reflecting lens is arranged on one side of the second reflecting lens, the third reflecting lens is located directly below the conical reflecting mirror, the second reflecting lens reflects the swinging laser to the third reflecting lens, the third reflecting lens is used to reflect the laser downward, a focusing lens is arranged below the third reflecting lens, a second collimating lens is arranged directly below the focusing lens, the laser passes through the central through hole of the semi-reflecting mirror through the focusing lens and the second collimating lens, and forms a point laser spot inside the annular laser spot.

[0011] Preferably, the nozzle includes a main body, a connector connected to the optical system is provided at the top of the main body, a light inlet for allowing the laser to pass through is provided on the connector, a wire feeding structure and a powder feeding structure are provided on the main body, the wire feeding structure and the powder feeding structure are coaxially arranged, a gas protection structure is provided on the main body, a fixed plate is provided on the main body, a plurality of first temperature detection components for detecting the temperature around the molten pool are provided on the fixed plate, and a second temperature detection component for detecting the heat affected zone of the weld is provided on the fixed plate.

[0012] Preferably, the wire feeding structure includes a wire feeding tube, a main body is provided with a plurality of mounting holes distributed in a circular array, the wire feeding tube is fixedly installed in the mounting holes, the annular laser is located inside the circle surrounded by the wire feeding tube, and the wire feeding tube is arranged in a mounting cavity arranged inside the main body; the powder feeding structure includes inclined powder feeding channels distributed in a circular array on the main body, the powder feeding channels are spaced apart from the wire feeding tube, and the powder feeding channels are located outside the wire feeding tube.

[0013] Preferably, the gas protection structure includes a first gas protection unit and a second gas protection unit, the first gas protection unit includes a ring block, the ring block is arranged on the top of the installation cavity, an annular semicircular air duct is arranged on the upper surface of the ring block, the air duct and the semicircular ring groove arranged on the main body are assembled into a circular protective gas channel, a first air inlet hole connected to the air duct is arranged on the top of the main body, a plurality of air outlet holes connected to the air duct are evenly arranged on the ring block, and the air outlet holes are arranged between the wire feeding tube and the powder feeding channel; the second gas protection unit includes an air cavity, a second air inlet hole connected to the air cavity is arranged on the upper surface of the main body, a plurality of inclined air pipes are evenly arranged in a circular array inside the main body, the air pipes are connected to the air cavity, and the air pipes are located outside the powder feeding channel.

[0014] Preferably, the first temperature detection component includes a first temperature sensor, a mounting groove for mounting the first temperature sensor is provided on the fixing plate, the first temperature sensor is rotatably connected to the mounting groove, and an angle adjustment structure for adjusting the angle of the first temperature sensor is provided on the fixing plate.

[0015] Preferably, the angle adjustment structure includes a fixed seat fixedly arranged on the fixed plate, a rotating block is rotatably arranged on the fixed seat, an outer surface of the rotating block is provided with external teeth, a driving gear meshing with the external teeth is arranged on the fixed seat, the driving gear is rotatably connected with the fixed frame, the fixed frame is fixedly arranged on the fixed seat, a slot for driving the wheel axle to rotate is arranged on the axle of the driving gear, internal teeth are arranged on the inner side surface of the rotating block, a driven gear meshing with the internal teeth is rotatably arranged on the fixed plate, and a slide rod is slidably arranged on the fixed plate The extension line of the slide rod passes through the axis of the body, the slide rod is provided with a rack meshing with the driven gear, the fixed seat is provided with a guide hole for the slide rod to pass through and has a guiding effect on the sliding of the slide rod, and a limit block is provided on the fixed plate for supporting and limiting the slide rod, the limit block is inserted in the slot provided at the bottom of the slide rod, the limit block is slidably connected to the slot, the end of the slide rod is provided with a transmission plate, and the transmission plate is provided with a vertical limit hole, and the fixing pin provided on the top of the first temperature sensor is located in the limit hole and is slidably connected to the limit hole.

[0016] Preferably, the second temperature detection component is symmetrically arranged on both sides of the fixed plate, the second temperature detection component includes a second temperature sensor, the second temperature sensor is rotatably arranged on the mounting frame, the mounting frame is arranged on the fixed plate, the second temperature sensor is located outside the first temperature sensor, a turntable for driving the second temperature sensor to rotate is arranged on the rotating shaft of the second temperature sensor, a locking wire for locking the turntable and the mounting frame is arranged on the turntable, and a scale is arranged on the side of the mounting frame.

[0017] The laser additive parts welding device and additive parts welding method based on the above energy precise control include the following steps:

[0018] S1. Move the nozzle to the position to be welded, turn the active gear, the active gear drives the rotating block to rotate through the external teeth, the rotating block drives the driven gear to rotate through the internal teeth, the driven gear drives the slide bar to slide through the rack, the slide bar drives the transmission plate to slide, the transmission plate drives the first temperature sensor to rotate through the limit hole and the fixing pin, and adjust the monitoring position of the first temperature sensor; loosen the locking wire, turn the turntable, the turntable drives the second temperature sensor to rotate, adjust the position of the second temperature sensor, and tighten the locking wire;

[0019] S2, adjusting the power and welding speed of the first laser and the second laser according to the composition of the first workpiece to be welded and the second workpiece to be welded and the required microstructure morphology;

[0020] S3, turning on the first laser and the second laser to weld the first workpiece to be welded and the second workpiece to be welded, the CCD camera, the first temperature sensor and the second temperature sensor move with the nozzle, the CCD camera monitors the morphology of the molten pool, the first temperature sensor and the second temperature sensor monitor the temperature of the molten pool and the heat-affected zone respectively, and transmit the monitored data to the control system in real time;

[0021] S4, the control system analyzes the energy density distribution characteristics of the molten pool according to the real-time data of the visual temperature sensing system, and adjusts the power and welding speed of the first laser and the second laser;

[0022] S5. After welding is completed, evaluate the welding quality and fine-tune the welding process parameters according to the evaluation results;

[0023] S6. The control system identifies and starts the repair function to repair the defects at the weld;

[0024] S7. The parameters, molten pool morphology, and temperature distribution data during the welding process are uploaded to the control system for storage.

[0025] The advantages and positive effects of the laser additive parts welding device and additive parts welding method with precise energy control described in the present invention are:

[0026] 1. The present invention adopts point-ring laser welding. The position of the ring laser spot is adjustable, and the point laser spot is a swinging laser. The ring laser spot and the point laser spot provide different heating conditions for the weld center and the weld edge, thereby improving the weld structure and improving the welding quality between the laser selectively melted parts and the laser directly deposited parts.

[0027] 2. Use silk powder mixed welding and set the silk powder intervals so that the silk powder composition can be specifically set as needed, which is conducive to sufficient filling of silk powder and improves welding quality.

[0028] 3. The provision of the first gas protection unit and the second gas protection unit improves the protection effect on the welding wire and welding powder.

[0029] 4. A first temperature sensor and a second temperature sensor are arranged on the nozzle. The first temperature sensor and the second temperature sensor monitor the temperature of the molten pool and the heat affected zone. The molten pool morphology is monitored by CCD. The control system adjusts the parameters of the first laser and the second laser based on the macro-micro coupling model through the real-time monitoring structure to improve the weld structure and welding performance.

[0030] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic diagram of the structure of an optical system according to an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of the three-dimensional structure of a nozzle according to an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of a nozzle cross-sectional structure according to an embodiment of the present invention;

[0034] Figure 4 A schematic diagram of a top view of a nozzle structure according to an embodiment of the present invention;

[0035] Figure 5 It is a schematic diagram of the side view structure of the nozzle of an embodiment of the present invention;

[0036] Figure 6 Schematic diagram of the ring block structure of an embodiment of the present invention.

[0037] Reference numerals

[0038] 1. Ring light optical system; 11. First laser; 12. First plane lens; 13. First flat top light shaping mirror; 14. Second flat top light shaping mirror; 15. Ring reflector; 16. Conical reflector; 17. Half reflector;

[0039] 2. Point light optical system; 21. Second laser; 22. Second plane lens; 23. First collimating lens; 24. First reflecting lens; 25. Y-axis galvanometer; 26. Second reflecting lens; 27. X-axis galvanometer; 28. Third reflecting lens; 29. ​​Focusing lens; 210. Second collimating lens;

[0040] 3. Nozzle; 31. Body; 32. Light inlet; 33. Mounting hole; 34. First air inlet; 35. Powder feeding channel; 36. Second air inlet; 37. Fixing plate; 38. First temperature sensor; 39. Mounting slot; 310. Fixing seat; 311. Driving gear; 312. Fixing frame; 313. Rotating block; 314. External teeth; 315. Internal teeth; 316. Driven gear; 317. Sliding rod; 318. Guide hole; 319. Limiting block; 320. Transmission plate; 321. Fixing pin; 322. Second temperature sensor; 323. Mounting frame; 324. Turntable; 325. Locking wire; 326. Wire feeding tube; 327. Ring block; 328. Airway; 329. Air outlet; 330. Air cavity; 331. Air pipe; 332. Mounting cavity;

[0041] 4. Workpiece; 41. First workpiece to be welded; 42. Second workpiece to be welded; 5. Control system; 6. Visual temperature sensing system. DETAILED DESCRIPTION

[0042] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0043] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0044] Example

[0045] A laser additive welding device with precise energy control includes: an optical system, a visual temperature sensing system 6 and a control system 5. The optical system is used to provide energy for welding, the visual temperature sensing system 6 is used to monitor the temperature and molten pool morphology at the welding position in real time, and the control system 5 is used to analyze and store data and adjust the parameters of the optical system according to the real-time data.

[0046] The optical system includes a ring light optical system 1 for forming an outer ring laser spot and a point light optical system 2 for forming a point laser spot, and the point laser spot is located inside the ring laser spot. The position of the ring laser spot is adjustable, and the point laser spot is a swinging laser. Different heating conditions are provided to the center and edge of the weld by the ring laser spot and the point laser spot, thereby improving the weld structure and the welding quality between the laser selective melting part and the laser direct deposition part.

[0047] like Figure 1 As shown. The ring light optical system 1 includes a first laser 11, a first plane lens 12 is arranged below the first laser 11, a first flat top light shaping mirror 13 and a second flat top light shaping mirror 14 are arranged below the first plane lens 12, and the laser emitted by the first laser 11 is arranged into parallel light by the first plane lens 12 and the first flat top light shaping mirror 13 and the second flat top light shaping mirror 14. A conical reflector 16 is arranged directly below the second flat top light shaping mirror 14, and the conical reflector 16 reflects the parallel light to both sides. An annular reflector 15 is arranged outside the conical reflector 16, and a half reflector 17 is arranged directly below the conical reflector 16. The laser is reflected from the annular reflector 15 to the half reflector 17, and a ring laser spot is formed by the half reflector 17.

[0048] like Figure 2As shown. The point light optical system 2 includes a second laser 21, a second plane lens 22 is arranged below the second laser 21, a first collimating lens 23 is arranged below the second plane lens 22, an inclined first reflecting lens 24 is arranged below the first collimating lens 23, and an X-direction galvanometer 27 is arranged on one side of the first reflecting lens 24. After passing through the first plane lens 12 and the first collimating lens 23, the laser is reflected by the first reflecting lens 24 to the X-direction galvanometer 27, and the X-direction galvanometer 27 provides laser swing in the X direction. A Y-direction galvanometer 25 is arranged below one side of the X-direction galvanometer 27, and the laser enters the Y-direction galvanometer 25 after being reflected by the X-direction galvanometer 27, and the Y-direction galvanometer 25 provides laser swing in the Y direction. A second reflecting lens 26 is arranged below the Y-direction galvanometer 25, and a third reflecting lens 28 is arranged on one side of the second reflecting lens 26. The angle between the third reflecting lens 28 and the horizontal plane is 45°, and the third reflecting lens 28 is located directly below the conical reflecting mirror 16. The second reflector 26 reflects the swinging laser to the third reflector 28, and the third reflector 28 is used to reflect the laser downward. A focusing lens 29 is arranged below the third reflector 28, and a second collimating lens 210 is arranged directly below the focusing lens 29. The laser passes through the central through hole of the semi-reflecting mirror 17 through the focusing lens 29 and the second collimating lens 210, and forms a point-shaped laser spot inside the annular laser spot.

[0049] The visual temperature sensing system 6 includes a CCD camera and a temperature sensor. The CCD camera is used to provide a visual field at the welding position and monitor the molten pool morphology. The CCD camera is fixed on the first laser 11 or the nozzle 3 and moves synchronously with the first laser 11 or the nozzle 3. The temperature sensor is set on the nozzle 3, and the nozzle 3 is fixed at the bottom of the annular light optical system 1 to monitor the temperature at the position to be welded.

[0050] The control system 5 adjusts the parameters of the optical system according to the molten pool morphology monitored by the CCD camera and the temperature monitored by the temperature sensor. The optical system, CCD camera and temperature sensor are all electrically connected to the control system 5. A macro-micro coupling model is set inside the control system 5, which can realize the "deconstruction" of the microstructure of each characteristic area of ​​the weld, establish the correlation between "energy density overflow ratio-macro temperature field flow field-micro flow field organization field", design the nucleation and growth rates in different areas such as the columnar dendrites at the edge of the weld, the equiaxed dendrite area in the center of the weld, and the equiaxed fine grain area near the fusion line, and couple the organization solutions of each area to the same solution domain of the entire weld to reproduce the dynamic evolution process of the solidification microstructure of the entire weld. The establishment of the macro-micro coupling model adopts the modeling method in the prior art CN201910771451.8.

[0051] like Figure 2-6As shown. The nozzle 3 includes a body 31, and the body 31 is a conical structure. The nozzle is fixed at the bottom end of the annular light optical system 1. A connector fixedly connected to the annular light optical system 1 is provided at the top of the body 31, and a light inlet 32 ​​for the laser to pass through is provided on the connector. A wire feeding structure and a powder feeding structure are provided on the body 31, and the wire feeding structure and the powder feeding structure are coaxially arranged to realize wire-powder mixed welding. The wire feeding structure includes a wire feeding tube 326, and a plurality of mounting holes 33 distributed in a circular array are provided on the body 31, and the wire feeding tube 326 is fixedly installed in the mounting hole 33. In this embodiment, there are four wire feeding tubes 326. The annular laser is located inside the circle surrounded by the wire feeding tube 326, and the wire feeding tube 326 is arranged in an installation cavity 332 arranged inside the body 31. The powder feeding structure includes inclined powder feeding channels 35 distributed in a circular array on the body 31, and the powder feeding channels 35 are arranged at intervals from the wire feeding tube 326, and the powder feeding channels 35 are located outside the wire feeding tube 326. Silk powder mixed welding is adopted, and the silk powder is arranged at intervals, so that the silk powder composition can be specifically arranged according to needs, which is conducive to sufficient filling of silk powder and improves welding quality.

[0052] A gas protection structure is provided on the body 31. The gas protection structure includes a first gas protection unit and a second gas protection unit. The first gas protection unit includes a ring block 327, which is fixedly arranged on the top of the installation cavity 332 by welding and sealing. An annular semicircular airway 328 is provided on the upper surface of the ring block 327, and the airway 328 and the semicircular annular groove provided on the body 31 are assembled into a circular protective gas channel. A first air inlet 34 connected to the airway 328 is provided at the top of the body 31. A plurality of air outlets 329 connected to the airway 328 are evenly provided on the ring block 327, and the air outlets 329 are arranged between the wire feeding tube 326 and the powder feeding channel 35. The inert protective gas enters the airway 328 through the first air inlet 34, and then is discharged through the air outlet 329 to protect the welding wire. The second gas protection unit includes an air cavity 330, and a second air inlet 36 connected to the air cavity 330 is provided on the upper surface of the body 31. The body 31 is evenly provided with a plurality of inclined gas pipes 331 in a circumferential array, the gas pipes 331 are connected to the gas cavity 330, and the gas pipes 331 are located outside the powder delivery channel 35. The inert shielding gas is sprayed downward through the gas cavity 330 and the gas pipes 331 to protect the welding powder. The provision of the first gas shielding unit and the second gas shielding unit improves the protection effect on the welding wire and the welding powder.

[0053] The body 31 is fixedly provided with a fixing plate 37, on which a plurality of first temperature detection components for detecting the temperature around the molten pool are provided, and the fixing plate 37 is provided with a second temperature detection component for detecting the heat-affected zone of the weld. The first temperature detection component includes a first temperature sensor 38, and the first temperature sensor 38 adopts an existing infrared temperature sensor. In this embodiment, six first temperature sensors 38 are provided. The fixing plate 37 is provided with a mounting groove 39 for mounting the first temperature sensor 38, and the first temperature sensor 38 is rotatably connected to the mounting groove 39. The fixing plate 37 is provided with an angle adjustment structure for adjusting the angle of the first temperature sensor 38.

[0054] The angle adjustment structure includes a fixed seat 310 fixedly arranged on a fixed plate 37, and a rotating block 313 is rotatably arranged on the fixed seat 310, and the rotating block 313 is coaxially arranged with the nozzle 3. An outer tooth 314 is arranged on the outer side of the rotating block 313, and a driving gear 311 meshing with the outer tooth 314 is arranged on the fixed seat 310. The driving gear 311 is rotatably connected with a fixed frame 312 through a bearing, and the fixed frame 312 is fixedly arranged on the fixed seat 310. A slot for driving the axle to rotate is arranged on the axle of the driving gear 311, and a wrench is inserted into the slot to drive the driving gear 311 to rotate. In order to improve the stability of the driving gear 311, a top screw is arranged at the top of the axle of the driving gear 311 to lock the driving gear 311. An inner tooth 315 is arranged on the inner side of the rotating block 313, and a driven gear 316 meshing with the inner tooth 315 is rotatably arranged on the fixed plate 37 through a bearing. The driven gear 316 corresponds to the first temperature sensor 38 one by one. A slide bar 317 is slidably provided on the fixed plate 37, and the extension line of the slide bar 317 passes through the axis of the main body 31. A rack meshing with the driven gear 316 is fixedly provided on the slide bar 317. A guide hole 318 is provided on the fixed seat 310 for the slide bar 317 to pass through and has a guiding effect on the sliding of the slide bar 317. A limit block 319 is provided on the fixed plate 37 to support and limit the slide bar 317. The limit block 319 is inserted into the slot provided at the bottom of the slide bar 317, and the limit block 319 is slidably connected to the slot. A transmission plate 320 is fixedly provided at the end of the slide bar 317, and a vertical limit hole is provided on the transmission plate 320. The fixing pin 321 provided at the top of the first temperature sensor 38 is located in the limit hole and is slidably connected to the limit hole.

[0055] The second temperature detection assembly is symmetrically arranged on both sides of the fixed plate 37. The second temperature detection assembly includes a second temperature sensor 322, which is an existing infrared temperature sensor. The second temperature sensor 322 is rotatably arranged on a mounting frame 323, and the mounting frame 323 is vertically fixedly arranged on the fixed plate 37. The second temperature sensor 322 is located outside the first temperature sensor 38. A turntable 324 that drives the second temperature sensor 322 to rotate is fixedly arranged on the rotating shaft of the second temperature sensor 322, and a locking wire 325 that locks the turntable 324 and the mounting frame 323 is arranged on the turntable 324. A scale is arranged on the side of the mounting frame 323 to facilitate observation of the rotation angle.

[0056] The laser additive parts welding device and additive parts welding method based on the above energy precise control include the following steps:

[0057] S1. Move the nozzle 3 to the position to be welded, rotate the active gear 311, the active gear 311 drives the rotating block 313 to rotate through the external teeth 314, the rotating block 313 drives the driven gear 316 to rotate through the internal teeth 315, the driven gear 316 drives the slide bar 317 to slide through the rack, the slide bar 317 drives the transmission plate 320 to slide, the transmission plate 320 drives the first temperature sensor 38 to rotate through the limit hole and the fixing pin 321, and adjusts the monitoring position of the first temperature sensor 38. Loosen the locking wire 325, rotate the turntable 324, the turntable 324 drives the second temperature sensor 322 to rotate, adjust the position of the second temperature sensor 322, and tighten the locking wire 325.

[0058] S2. According to the composition of the first part 41 to be welded and the second part 42 to be welded of the workpiece 4 and the required microstructure morphology, the power and welding speed of the first laser 11 and the second laser 21 and the swing parameters of the second laser 21 are adjusted.

[0059] S3, turn on the first laser 11 and the second laser 21, and weld the first workpiece 41 and the second workpiece 42. The CCD camera, the first temperature sensor 38, and the second temperature sensor 322 move with the nozzle 3, the CCD camera monitors the morphology of the molten pool, the first temperature sensor 38 and the second temperature sensor 322 monitor the temperature of the molten pool and the heat-affected zone respectively, and transmit the monitored data to the control system 5 in real time.

[0060] S4. The control system 5 analyzes the energy density distribution characteristics of the molten pool according to the real-time data of the visual temperature sensing system 6, and adjusts the power and welding speed of the first laser 11 and the second laser 21 based on the correlation between "energy density overflow ratio-macroscopic temperature field flow field-microscopic flow field organization field", so as to dynamically adjust the nucleation and growth rates of each characteristic area of ​​the weld and optimize the weld microstructure.

[0061] S5. After welding is completed, the control system 5 compares the welding microstructure reconstructed based on the macro-micro coupling model with the actual welding result, evaluates the welding quality, and fine-tunes the welding process parameters according to the evaluation results.

[0062] S6. The control system 5 identifies and starts the repair function, adjusts the power and welding speed and other parameters of the first laser 11 and the second laser 21, repairs the defective area at the weld, and improves the overall stability of the welding quality.

[0063] S7. The parameters, molten pool morphology, and temperature distribution data during the welding process are uploaded to the control system 5 for storage, providing a reference and basis for subsequent manufacturing, thereby achieving continuous optimization and improvement of the manufacturing process.

[0064] Therefore, by using the laser additive parts welding device and method with precise energy control described in the present invention, the power and welding speed of the laser are adjusted through real-time temperature and molten pool morphology feedback, thereby improving the welding quality between the laser selectively melted parts and the laser directly deposited parts.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A laser additive welding device with precise energy control, characterized in that: include: An optical system, the optical system includes a ring light optical system for forming an outer ring laser spot and a point light optical system for forming a point laser spot, wherein the point laser spot is located inside the ring laser spot and is used to provide heating energy; Visual temperature sensing system, the visual temperature sensing system includes a CCD camera and a temperature sensor. The CCD camera is used to provide a field of view at the welding position and monitor the morphology of the molten pool; the temperature sensor is set on the nozzle, and the nozzle is fixed at the bottom of the optical system to monitor the temperature at the position to be welded; A control system, wherein the control system adjusts the parameters of the optical system according to the molten pool morphology monitored by the CCD camera and the temperature monitored by the temperature sensor, and the optical system, the CCD camera and the temperature sensor are all electrically connected to the control system; The annular light optical system comprises a first laser, a first plane lens is arranged below the first laser, a first flat top light shaping mirror and a second flat top light shaping mirror are arranged below the first plane lens, the laser emitted by the first laser is arranged into parallel light by the first plane lens and the second flat top light shaping mirror, a conical reflector is arranged directly below the second flat top light shaping mirror, the conical reflector reflects the parallel light to both sides, an annular reflector is arranged outside the conical reflector, a half reflector is arranged directly below the conical reflector, the laser is reflected to the half reflector by the annular reflector, and an annular laser spot is formed by the half reflector; The point light optical system includes a second laser, a second plane lens is arranged below the second laser, a first collimating lens is arranged below the second plane lens, an inclined first reflecting lens is arranged below the first collimating lens, an X-direction galvanometer is arranged on one side of the first reflecting lens, the laser passes through the first plane lens and the first collimating lens and then is reflected to the X-direction galvanometer by the first reflecting lens, the X-direction galvanometer provides laser swing in the X direction, a Y-direction galvanometer is arranged below one side of the X-direction galvanometer, the laser enters the Y-direction galvanometer after being reflected by the X-direction galvanometer, the Y-direction galvanometer provides laser swing in the Y direction, a second reflecting lens is arranged below the Y-direction galvanometer, a third reflecting lens is arranged on one side of the second reflecting lens, the third reflecting lens is located directly below the conical reflecting mirror, the second reflecting lens reflects the swinging laser to the third reflecting lens, the third reflecting lens is used to reflect the laser downward, a focusing lens is arranged below the third reflecting lens, a second collimating lens is arranged directly below the focusing lens, the laser passes through the central through hole of the semi-reflecting mirror through the focusing lens and the second collimating lens, and forms a point laser spot inside the annular laser spot.

2. The laser additive welding device with precise energy control according to claim 1, characterized in that: The nozzle includes a main body, a connector connected to the optical system is arranged at the top of the main body, a light inlet for laser passing through is arranged on the connector, a wire feeding structure and a powder feeding structure are arranged on the main body, the wire feeding structure and the powder feeding structure are arranged coaxially, a gas protection structure is arranged on the main body, a fixed plate is arranged on the main body, a plurality of first temperature detection components for detecting the temperature around the molten pool are arranged on the fixed plate, and a second temperature detection component for detecting the heat affected zone of the weld is arranged on the fixed plate.

3. The laser additive welding device with precise energy control according to claim 2, characterized in that: The wire feeding structure includes a wire feeding tube, a main body is provided with a plurality of mounting holes distributed in a circular array, the wire feeding tube is fixedly installed in the mounting holes, the annular laser is located inside the circle surrounded by the wire feeding tube, and the wire feeding tube is arranged in a mounting cavity arranged inside the main body; the powder feeding structure includes an inclined powder feeding channel distributed in a circular array on the main body, the powder feeding channel is spaced apart from the wire feeding tube, and the powder feeding channel is located outside the wire feeding tube.

4. The laser additive welding device with precise energy control according to claim 3, characterized in that: The gas protection structure includes a first gas protection unit and a second gas protection unit. The first gas protection unit includes a ring block, which is arranged on the top of the installation cavity. A ring-shaped semicircular air duct is arranged on the upper surface of the ring block. The air duct and the semicircular ring groove arranged on the main body are assembled into a circular protective gas channel. A first air inlet hole connected to the air duct is arranged on the top of the main body. A plurality of air outlet holes connected to the air duct are evenly arranged on the ring block. The air outlet holes are arranged between the wire feeding tube and the powder feeding channel. The second gas protection unit includes an air cavity. A second air inlet hole connected to the air cavity is arranged on the upper surface of the main body. A plurality of inclined air pipes are evenly arranged in a circular array inside the main body. The air pipes are connected to the air cavity. The air pipes are located outside the powder feeding channel.

5. The laser additive welding device with precise energy control according to claim 4, characterized in that: The first temperature detection component includes a first temperature sensor. A mounting groove for mounting the first temperature sensor is arranged on the fixing plate. The first temperature sensor is rotatably connected to the mounting groove. An angle adjustment structure for adjusting the angle of the first temperature sensor is arranged on the fixing plate.

6. The laser additive welding device with precise energy control according to claim 5, characterized in that: The cam is provided with a toothed plate, and the toothed plate ...

7. The laser additive welding device with precise energy control according to claim 6, characterized in that: The second temperature detection component is symmetrically arranged on both sides of the fixed plate, the second temperature detection component includes a second temperature sensor, the second temperature sensor is rotatably arranged on the mounting frame, the mounting frame is arranged on the fixed plate, the second temperature sensor is located outside the first temperature sensor, a turntable for driving the second temperature sensor to rotate is arranged on the rotating shaft of the second temperature sensor, a locking wire for locking the turntable and the mounting frame is arranged on the turntable, and a scale is arranged on the side of the mounting frame.

8. A welding method based on a laser additive parts welding device with precise energy control according to claim 7, characterized in that: The following steps are involved: S1. Move the nozzle to the position to be welded, turn the active gear, the active gear drives the rotating block to rotate through the external teeth, the rotating block drives the driven gear to rotate through the internal teeth, the driven gear drives the slide bar to slide through the rack, the slide bar drives the transmission plate to slide, the transmission plate drives the first temperature sensor to rotate through the limit hole and the fixing pin, and adjust the monitoring position of the first temperature sensor; loosen the locking wire, turn the turntable, the turntable drives the second temperature sensor to rotate, adjust the position of the second temperature sensor, and tighten the locking wire; S2, adjusting the power and welding speed of the first laser and the second laser according to the composition of the first workpiece to be welded and the second workpiece to be welded and the required microstructure morphology; S3, turning on the first laser and the second laser to weld the first workpiece to be welded and the second workpiece to be welded, the CCD camera, the first temperature sensor and the second temperature sensor move with the nozzle, the CCD camera monitors the morphology of the molten pool, the first temperature sensor and the second temperature sensor monitor the temperature of the molten pool and the heat-affected zone respectively, and transmit the monitored data to the control system in real time; S4. Define the energy density E0 applied by the point laser and the energy density E applied by the ring laser c The obtained energy density overflow ratio quantifies the energy accumulation degree γ of different micro-areas. The control system analyzes the energy density distribution characteristics of the molten pool according to the real-time data of the visual temperature sensing system and adjusts the power and welding speed of the first laser and the second laser; S5. After welding is completed, evaluate the welding quality and fine-tune the welding process parameters according to the evaluation results; S6. The control system identifies and starts the repair function to repair the defects at the weld; S7. The parameters, molten pool morphology, and temperature distribution data during the welding process are uploaded to the control system for storage.

Images