CN117259991A - On-line detection method for penetration state of laser-MIG (metal-inert gas welding) composite welding - Google Patents
On-line detection method for penetration state of laser-MIG (metal-inert gas welding) composite welding Download PDFInfo
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- CN117259991A CN117259991A CN202311366782.6A CN202311366782A CN117259991A CN 117259991 A CN117259991 A CN 117259991A CN 202311366782 A CN202311366782 A CN 202311366782A CN 117259991 A CN117259991 A CN 117259991A
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- 238000003466 welding Methods 0.000 title claims abstract description 126
- 230000035515 penetration Effects 0.000 title claims abstract description 103
- 238000001514 detection method Methods 0.000 title claims abstract description 100
- 239000002131 composite material Substances 0.000 title claims abstract description 61
- 239000011261 inert gas Substances 0.000 title description 2
- 239000000523 sample Substances 0.000 claims abstract description 33
- 238000000034 method Methods 0.000 claims abstract description 30
- 238000012545 processing Methods 0.000 claims abstract description 8
- 230000003287 optical effect Effects 0.000 claims description 25
- 230000008569 process Effects 0.000 claims description 15
- 238000001914 filtration Methods 0.000 claims description 7
- 239000013307 optical fiber Substances 0.000 claims description 7
- 238000005070 sampling Methods 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 abstract description 11
- 238000005516 engineering process Methods 0.000 abstract description 7
- 239000010931 gold Substances 0.000 description 8
- 229910052737 gold Inorganic materials 0.000 description 8
- 238000010587 phase diagram Methods 0.000 description 8
- 230000009286 beneficial effect Effects 0.000 description 4
- 230000004927 fusion Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000012797 qualification Methods 0.000 description 3
- 238000010891 electric arc Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000011897 real-time detection Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- -1 Fang Cunzai plumes Substances 0.000 description 1
- 238000012952 Resampling Methods 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000010365 information processing Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000007781 pre-processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/346—Working by laser beam, e.g. welding, cutting or boring in combination with welding or cutting covered by groups B23K5/00 - B23K25/00, e.g. in combination with resistance welding
- B23K26/348—Working by laser beam, e.g. welding, cutting or boring in combination with welding or cutting covered by groups B23K5/00 - B23K25/00, e.g. in combination with resistance welding in combination with arc heating, e.g. TIG [tungsten inert gas], MIG [metal inert gas] or plasma welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/70—Auxiliary operations or equipment
- B23K26/702—Auxiliary equipment
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- Plasma & Fusion (AREA)
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- Arc Welding In General (AREA)
Abstract
An online detection method for penetration state of laser-MIG composite welding belongs to the technical field of laser processing. The invention aims to solve the problem that the prior art lacks a welding seam penetration on-line monitoring and penetration state detection technology under the complex working condition of laser-MIG composite welding. The method comprises the following steps: 1. the probe is coaxially coupled with the laser head; 2. calibrating a system; 3. laser-MIG hybrid welding. The invention is used for the on-line detection of the penetration state of the laser-MIG composite welding.
Description
Technical Field
The invention belongs to the technical field of laser processing.
Background
The welding penetration is critical to the laser welding quality, and as the laser welding is applied to the connection of more complex structural members, the welding penetration condition of a welding line cannot be intuitively judged from the appearance due to the structural specificity, and the traditional post-welding detection method is difficult to realize the comprehensive detection of the welding line; more critical is that the traditional post-welding detection cannot adjust the welding process on line in real time according to the monitoring result. Therefore, the real-time on-line monitoring of the weld penetration is realized, and the welding process parameters are adjusted in real time according to the monitoring data in the laser welding process, so that the method has important significance for improving the quality of the laser welding weld, improving the production efficiency and improving the product qualification rate.
The laser-MIG composite welding is a welding method which couples two heat sources of laser and electric arc to act on the same area, extends the respective advantages of the laser and electric arc heat sources, overcomes the defects of the two heat sources when acting independently, has the advantages of large penetration, small heat input, high welding efficiency, strong gap adaptability and the like, and is an efficient welding mode.
The laser-MIG hybrid welding can produce a series of complex phenomena by coupling two heat sources with completely different heat and mass transfer mechanisms. Substances such as Fang Cunzai plumes, metal splashes, particle clusters and the like on a keyhole generated in the laser-MIG composite welding process have serious interference on penetration information acquisition, and difficulty is brought to online direct observation of welding states and real-time adjustment of the laser-MIG composite welding process.
At present, the development time of the laser welding weld penetration state post-welding detection technology is long, such as ultrasonic detection, ray detection and the like. Research work of laser welding on-line detection technology is carried out by scientific researchers at home and abroad. However, a technology and a system for on-line monitoring of weld penetration and detection of penetration state under the complex working condition of laser-MIG composite welding are still to be developed.
Disclosure of Invention
The invention aims to solve the problems that the prior art lacks welding seam penetration on-line monitoring and penetration state detection technology under the complex working condition of laser-MIG composite welding, and further provides a penetration state on-line detection method of laser-MIG composite welding.
The on-line detection method of the penetration state of the laser-MIG composite welding comprises the following steps:
1. the probe is coaxially coupled with the laser head:
coaxially integrating and assembling a detection laser head and a laser welding head to obtain a penetration state online detection system for laser-MIG composite welding;
2. and (3) system calibration:
before welding, aligning the detection laser with a processing laser center, denoising the system, and adjusting a reference plane of the system;
3. laser-MIG hybrid welding:
and clamping and fixing the welded workpiece, setting laser-MIG composite welding technological parameters, starting a detection laser head while the laser-MIG composite welding process is performed, and measuring weld penetration curve data to complete the on-line detection method of the penetration state of the laser-MIG composite welding.
The beneficial effects of the invention are as follows:
1. the method can simultaneously acquire the weld penetration curve along with the laser-MIG composite welding process, and realizes the weld penetration real-time detection and the real-time judgment of the penetration state of the laser-MIG composite welding.
2. The method is based on the spectral domain optical low coherence technology principle, depth information in a keyhole of a molten pool is obtained through detection light, a fusion depth curve of a welding line is obtained in real time by combining denoising and fitting of a filtering algorithm, the fusion penetration state of the welding line is accurately judged, and the measurement error is not more than 5%.
3. The method provides reference for adjusting the technological parameters of the laser-MIG composite welding in real time through the on-line judgment of the penetration state of the welding seam, improves the quality of the laser-MIG composite welding, and is beneficial to improving the production efficiency and the product qualification rate of the laser-MIG composite welding.
Drawings
Fig. 1 is a state detection of an un-penetration sample in a laser-MIG hybrid welding penetration state online detection method in a first embodiment, 1 is a 1-gold phase diagram of the un-penetration sample, 2 is a 2-gold phase diagram of the un-penetration sample, and 3 is a penetration monitoring interface of an un-penetration weld;
fig. 2 is a state detection of a penetration sample in the on-line detection method of the penetration state of the laser-MIG composite welding in the first embodiment, 1 is a 3-gold phase diagram of the penetration sample, 2 is a 4-gold phase diagram of the penetration sample, and 3 is a penetration weld penetration monitoring interface.
Detailed Description
The first embodiment is as follows: the embodiment is a method for detecting the penetration state of laser-MIG composite welding on line, which comprises the following steps:
1. the probe is coaxially coupled with the laser head:
coaxially integrating and assembling a detection laser head and a laser welding head to obtain a penetration state online detection system for laser-MIG composite welding;
2. and (3) system calibration:
before welding, aligning the detection laser with a processing laser center, denoising the system, and adjusting a reference plane of the system;
3. laser-MIG hybrid welding:
and clamping and fixing the welded workpiece, setting laser-MIG composite welding technological parameters, starting a detection laser head while the laser-MIG composite welding process is performed, and measuring weld penetration curve data to complete the on-line detection method of the penetration state of the laser-MIG composite welding.
The on-line detection system for the penetration state of the laser-MIG composite welding in the first step mainly comprises five parts: control host, optical chassis, optical reference arm module, optical sample arm module and optical fiber device connecting each part:
the control host is an information processing core of the system and can perform image acquisition of a spectrometer, control scanning of a galvanometer, depth information extraction of a welding line and the like.
The optical chassis is a laser output and receiving unit of the system, and the internal core devices are a light source, a spectrometer and a control PLC unit: the light source is a broadband SLD light source and provides an optical signal for the system; the spectrometer is an interference signal high-speed acquisition unit of the system and provides original data for system algorithm processing; the control PLC unit is an electric signal input and output interface of the laser welding penetration information monitoring equipment, can control linear movement of a reference arm (axial precision reaches 0.01mm, transverse precision reaches 0.05 mm), and links external equipment such as a robot, a welding machine tool and the like.
The optical reference arm module provides a reference signal for the Michelson interference system and interferes with a sample arm signal containing sample morphology information. The reference arm can realize electric adjustment of the reference optical path, so that the position of the reference plane is measured by the adjustment system, and the laser welding heads with different focal lengths are adapted.
The optical sample arm module is responsible for controlling the probe light to scan the surface of the workpiece and collecting the light information returned from the surface of the workpiece, and the core devices are an optical fiber collimating mirror, a vibrating mirror, a dichroic mirror and the like: the optical fiber collimation structure can adjust the distance between the end face of the optical fiber and the collimation lens; the vibrating mirror can control the position and scanning track of the detection laser.
The laser-MIG composite welding penetration state online detection system further comprises a welding head adapter, visible light and detection light can be split, the welding head can be connected into the penetration state online detection system and the coaxial CCD camera simultaneously, the adapter is connected with the welding head and the vibrating mirror through bolts, and connection reliability is guaranteed.
And thirdly, acquiring weld penetration curve data according to the principle that a detection laser head is controlled by a two-dimensional vibrating mirror to detect laser to scan a welding pool in the laser-MIG composite welding process, so as to obtain a penetration original signal. The original information acquired by the spectrometer is subjected to signal preprocessing, direct current item removal, wavelength intensity resampling and inverse Fourier change processing to obtain accurate weld penetration information; in addition, the system adopts a filtering algorithm to carry out denoising treatment on the penetration signal so as to ensure the penetration information and the detection precision of penetration state, and the method comprises noise region division, percentage filtering and mean value filtering based on the poisson distribution principle, so that a real-time high-precision weld penetration curve is finally obtained.
The on-line detection system for the penetration state of the embodiment is coaxially connected with the laser welding head through a CCD camera interface of the welding head.
The beneficial effects of this embodiment are:
1. the method can simultaneously acquire the weld penetration curve along with the laser-MIG composite welding process, and realizes the real-time detection of the weld penetration of the laser-MIG composite welding and the real-time judgment of the penetration state.
2. The method of the embodiment is based on the spectral domain optical low coherence technology principle, depth information in a keyhole of a molten pool is obtained through detection light, a fusion depth curve of a welding line is obtained in real time by combining denoising and fitting of a filtering algorithm, the fusion penetration state of the welding line is accurately judged, and the measurement error is not more than 5%.
3. The method of the embodiment provides a reference for adjusting the technological parameters of the laser-MIG composite welding in real time through the on-line judgment of the penetration state of the welding seam, improves the quality of the laser-MIG composite welding, and is beneficial to improving the production efficiency and the product qualification rate of the laser-MIG composite welding.
The second embodiment is as follows: the first difference between this embodiment and the specific embodiment is that: and in the first step, the detection laser head, the control host and the optical chassis are connected by using the detection head control cable, the detection head power supply cable and the optical unit control cable. The other is the same as in the first embodiment.
And a third specific embodiment: this embodiment differs from one or both of the embodiments in that: and thirdly, acquiring depth information of a keyhole of a molten pool by a detection laser head, and acquiring weld penetration curve data by denoising and fitting through an algorithm. The other is the same as the first or second embodiment.
The specific embodiment IV is as follows: this embodiment differs from one of the first to third embodiments in that: the algorithm denoising is a filtering algorithm. The other embodiments are the same as those of the first to third embodiments.
Fifth embodiment: this embodiment differs from one to four embodiments in that: the detection depth of the detection laser head in the first step is 2 mm-12 mm. The other embodiments are the same as those of the first to fourth embodiments.
Specific embodiment six: this embodiment differs from one of the first to fifth embodiments in that: the detection range of the detection laser head in the first step is 20mm multiplied by 20mm. The other embodiments are the same as those of the first to fifth embodiments.
Seventh embodiment: this embodiment differs from one of the first to sixth embodiments in that: the sampling frequency of the detection laser head in the first step is 250kHz. The other embodiments are the same as those of the first to sixth embodiments.
Eighth embodiment: this embodiment differs from one of the first to seventh embodiments in that: in the third step, the penetration state on-line detection method of the laser-MIG composite welding has a penetration detection error of not more than 5%. The other is the same as in embodiments one to seven.
Detailed description nine: this embodiment differs from one to eight of the embodiments in that: the laser-MIG composite welding penetration state online detection system comprises a control host, an optical chassis, an optical reference arm module, an optical sample arm module and an optical fiber device. The others are the same as in embodiments one to eight.
Detailed description ten: this embodiment differs from one of the embodiments one to nine in that: the axial movement precision of the laser-MIG composite welding penetration state online detection system in the first step is 0.01mm, and the transverse movement precision is 0.05mm. The others are the same as in embodiments one to nine.
The following examples are used to verify the benefits of the present invention:
embodiment one:
the on-line detection method of the penetration state of the laser-MIG composite welding comprises the following steps:
1. the probe is coaxially coupled with the laser head:
coaxially integrating a detection laser head and a laser welding head;
2. and (3) system calibration:
before welding, aligning the detection laser with a processing laser center, denoising the system, and adjusting a reference plane of the system;
3. laser-MIG hybrid welding:
and clamping and fixing the welded workpiece, setting laser-MIG composite welding technological parameters, starting a detection laser head while the laser-MIG composite welding process is performed, and measuring weld penetration curve data to complete the on-line detection method of the penetration state of the laser-MIG composite welding.
And in the first step, the detection laser head, the control host and the optical chassis are connected by using the detection head control cable, the detection head power supply cable and the optical unit control cable.
And thirdly, acquiring depth information of a keyhole of a molten pool by a detection laser head, and acquiring weld penetration curve data by denoising and fitting through an algorithm.
The detection depth of the detection laser head in the first step is 2 mm-12 mm.
The detection range of the detection laser head in the first step is 20mm multiplied by 20mm.
The sampling frequency of the detection laser head in the first step is 250kHz.
The laser-MIG composite welding penetration state online detection system comprises a control host, an optical chassis, an optical reference arm module, an optical sample arm module and an optical fiber device.
And in the third step, the welding workpiece is a No. 45 steel plate, and the thickness of the plate is 5mm.
Four different laser-MIG composite welding process parameters are selected to respectively process four welding workpieces, so that under the welding process parameters, samples 1 and 2 are in an unfermeable state, and samples 3 and 4 are in a penetration state;
fig. 1 is a state detection of an un-penetration sample in a laser-MIG hybrid welding penetration state online detection method in a first embodiment, 1 is a 1-gold phase diagram of the un-penetration sample, 2 is a 2-gold phase diagram of the un-penetration sample, and 3 is a penetration monitoring interface of an un-penetration weld; the metallographic penetration of the measured sample 1 is 2.33mm; the metallographic penetration of the measured sample 2 is 2.34mm, and the welding seams of the two samples are in an unfermeable state; and the welding seam results detected by the on-line detection method of the penetration state of the laser-MIG composite welding are all 2.3mm, the non-penetration state is accurately judged, and the penetration detection error is not more than 2%.
Fig. 2 is a state detection of a penetration sample in the on-line detection method of the penetration state of the laser-MIG composite welding in the first embodiment, 1 is a 3-gold phase diagram of the penetration sample, 2 is a 4-gold phase diagram of the penetration sample, and 3 is a penetration weld penetration monitoring interface. The metallographic penetration of the measured sample 3 is 5.4mm; the metallographic penetration of the measured sample 4 is 5.4mm, and the welding seams of the two samples are in penetration states; and the welding seam results detected by the on-line detection method of the penetration state of the laser-MIG composite welding are all 5mm, the penetration state is accurately judged, and the penetration detection error is not more than 5%.
Claims (10)
1. The on-line detection method for the penetration state of the laser-MIG composite welding is characterized by comprising the following steps of:
1. the probe is coaxially coupled with the laser head:
coaxially integrating and assembling a detection laser head and a laser welding head to obtain a penetration state online detection system for laser-MIG composite welding;
2. and (3) system calibration:
before welding, aligning the detection laser with a processing laser center, denoising the system, and adjusting a reference plane of the system;
3. laser-MIG hybrid welding:
and clamping and fixing the welded workpiece, setting laser-MIG composite welding technological parameters, starting a detection laser head while the laser-MIG composite welding process is performed, and measuring weld penetration curve data to complete the on-line detection method of the penetration state of the laser-MIG composite welding.
2. The method for on-line detection of penetration state of laser-MIG hybrid welding according to claim 1, wherein in the first step, the probe head control cable, the probe head power supply cable, the optical unit control cable are used to connect the probe head, the control host and the optical box.
3. The online detection method for the penetration state of laser-MIG composite welding is characterized in that in the third step, depth information in a keyhole of a molten pool is obtained through a detection laser head, and weld penetration curve data is obtained through algorithm denoising and fitting.
4. The method for online detection of penetration state of laser-MIG composite welding according to claim 3, wherein the algorithm denoising is a filtering algorithm.
5. The on-line detection method for the penetration state of laser-MIG composite welding according to claim 1, wherein the detection depth of the detection laser head in the first step is 2 mm-12 mm.
6. The on-line detection method for the penetration state of laser-MIG composite welding according to claim 1, wherein the detection range of the detection laser head in the first step is 20mm x 20mm.
7. The method for on-line detection of penetration state of laser-MIG composite welding of claim 1, wherein the sampling frequency of the probe laser head in the first step is 250kHz.
8. The on-line detection method for the penetration state of the laser-MIG composite welding according to claim 1, wherein the penetration detection error of the on-line detection method for the penetration state of the laser-MIG composite welding in the third step is not more than 5%.
9. The method for on-line detection of penetration state of laser-MIG hybrid welding according to claim 1, wherein the system for on-line detection of penetration state of laser-MIG hybrid welding in the first step includes a control host, an optical chassis, an optical reference arm module, an optical sample arm module, and an optical fiber device.
10. The online detection method for the penetration state of the laser-MIG composite welding according to claim 1, wherein the online detection system for the penetration state of the laser-MIG composite welding in the first step has the axial movement precision of 0.01mm and the transverse movement precision of 0.05mm.
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| CN202311366782.6A CN117259991A (en) | 2023-10-20 | 2023-10-20 | On-line detection method for penetration state of laser-MIG (metal-inert gas welding) composite welding |
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| CN202311366782.6A CN117259991A (en) | 2023-10-20 | 2023-10-20 | On-line detection method for penetration state of laser-MIG (metal-inert gas welding) composite welding |
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