CN102049613B - Online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on characteristic element plasma optical signal - Google Patents
Online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on characteristic element plasma optical signal Download PDFInfo
- Publication number
- CN102049613B CN102049613B CN 201010553902 CN201010553902A CN102049613B CN 102049613 B CN102049613 B CN 102049613B CN 201010553902 CN201010553902 CN 201010553902 CN 201010553902 A CN201010553902 A CN 201010553902A CN 102049613 B CN102049613 B CN 102049613B
- Authority
- CN
- China
- Prior art keywords
- optical signal
- plasma optical
- welding
- plasma
- galvanized steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Laser Beam Processing (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Abstract
The invention discloses an online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on a characteristic element plasma optical signal, comprising the following steps: welding the galvanized steel with a focused laser beam; simultaneously, adding copper powder at a welding part in the welding process; acquiring the characteristic element plasma optical signal in the laser powder-adding welding process of the galvanized steel by a photosensitive sensor; implementing online monitoring on types of the characteristic elements of the plasma generated by ionization of materials in the welding process and additive amount m of corresponding characteristic elements according to variation of the characteristic element plasma optical signal; and finally, obtaining relation between the characteristic element plasma optical signal and the welding defects. In the method, properties of the characteristic elements to the plasma optical signals are analyzed so as to judge whether the welding defects are generated and the generation time on line in real time, and the method can be used for online monitoring of defects in the laser welding process in practical production, and laying the foundation for online quality control of following laser welding processes.
Description
Technical field
The present invention relates to weld defect inline diagnosis field in the laser beam welding, be specially the inline diagnosis method that a kind of galvanized steel laser based on characteristic element plasma optical signal adds weld defect in the powder welding process.
Background technology
People such as the Duan Aiqin of China utilize the dynamic changing process of high-speed camera and two kinds of means article on plasma of optical monitoring signal body and deep research have been carried out in the influence of welding stability.Proposed to be divided into four-stage in each cycle of variation of plasma, and the basic reason that influences welding stability is the fluctuation of plasma between penetrating and not penetrating.Also propose the infrared signal measurement of molten bath, the back side and front multiple sensor signals in addition and merge two kinds of unstable perforation procedure method for real time discriminating.Utilize this two kinds of method of discrimination, stainless welding process is judged, the result shows, under the study condition of this paper, to wall scroll weld seam and different weld classification discrimination all near 100%.Comprehensive above result of study, in laser full penetration welding process, the strict welding parameter of selecting, in welding process, keep molten bath, rational back side length, both can obtain stable perforation procedure, and also can reduce the probability that defective such as pore produces, the tissue that also can control weld seam simultaneously forms, to this further research, will provide fundamental basis and implementation method for the strict control of the quality of actual welding process.People such as Hu Lunji utilize the photo plasma acoustical signal to monitor a kind of method of weld seam penetration.In the literary composition by experimental study, when having obtained the weld seam penetration and having changed, the Changing Pattern of photo plasma acoustical signal, thereby but set up a kind of method of face monitoring weld seam penetration.When having analyzed laser power variation from the intensity of signal in this method research, the Changing Pattern of the acoustical signal of plasma is judged the welding penetration by the acoustical signal characteristic frequency.People such as Zhu Qiongyu study weldquality and the corresponding signal characteristic thereof of laser assembly solder under the different gap, the axis light signal when welding under the multiple gap is extracted in the coaxial sensor-based system collection of employing self-control, and signal is carried out modal analysis, segmented power analysis of spectrum and wavelet analysis.The result shows, the sum of axis light signal amplitude is in the weld seam section of different gap, accumulate in the different interval of linear separability, can effectively separate the different I class of welding quality, II class, III class weld seam, the segmented power analysis of spectrum of signal can reflect the variation of welded condition comparatively intuitively.The 4th layer of approximation signal after the axis light signal wavelet decomposition can identify the measured I class of matter weld seam intuitively.The 3rd layer, the 4th layer detail signal of axis light signal can clearly pick out bum II class weld seam.Though this method can compare research to corresponding welding process, welding line joint quality, seeks the inner link between signal characteristic and the welding quality.People such as Zhang Linjie utilize the CCD high-speed photography to study the variation of photo plasma form in the Laser Deep Penetration Welding process under the different side-blown conditions, set up the two-dimentional compressible model in simulated laser penetration fustion welding process gas flow field, calculated the variation of side-blown nozzle height and side-blown flow velocity to the influence of laser weld photo plasma.This detection method adopts side-blown nozzle height and the side-blown flow velocity optimized to suppress photo plasma effectively, and the welding process heat transference efficiency is improved.
People such as Miyamoto and Maruo utilize spectrum to calculate and have obtained CO
2Electron densities during the laser weld steel etc. equal 2kW and 3kW respectively in laser power, and during argon shield, apart from surperficial 0.5mm height, its electron density is 2 * 10
16～2 * 10
17Cm
-3, and electron temperature is about 9000-13000K; During as the protective gas weldable steel, the electron density that obtains surface plasma is 4 * 10 to people such as Szymanski and Kurzyna at helium
16Cm
-3, electron temperature is 8000K; Under the same conditions, argon gas is during as protective gas, and electron density is 8.5 * 10
16Cm
-3, electron temperature is 8600K; Other researchers also obtain the conclusion that is more or less the same; Doctor Su Yandong then passes through CO
2The research of laser weld spectrum is calculated and have been obtained the related of electron density and welding penetration, weld heat input, and described the influence of plasma to welding process; When people such as B.J.Aalderink have studied the welding of YAG laser jigsaw, the main distribution characteristics of spectrum.These researchers are temperature, the electron densities of analyzing the plasma the laser beam welding from the angle of spectra methods.Because in the laser beam welding, sound and optic signal also is easy to generate.Sound and light signal has reflected laser beam welding, and has certain correlation with welding quality, thereby signals such as utilization sound, light are monitored welding quality and become an important research direction.That utilizes in early days that infrared and Ultraviolet sensor carries out laser beam welding research has W.M.Steen, H.B.Chen, a D.J.Brooktield and K.Williams etc., mainly be to utilize infrared and ultraviolet light intensity to identify several welded conditions, comprising: satisfy the weld seam of quality requirement, the weld seam that has blemish, incomplete penetration defect, its result shows infrared and ultraviolet light has advantage in real-time monitoring welding quality.And D.Maischner etc., developed method that a kind of metal vapors plasma light signal characteristic from the workpiece above and below determines the welding penetration below, having or not when monitor signal and aperture folding are synchronous, up, the vibration frequency of metal vapors plasma optical signal is relevant with penetrability.People such as P.G.Sanders have developed a kind of infrared sensor for monitoring welding penetration, and low frequency infrared signal intensity reduces suddenly when penetrating fully, between infrared signal intensity and the penetration depth linear relationship is arranged.And S.Postma has obtained identical result in the research of Infrared Sensor System.The research of audible sound can be traced back to Dixon and Lewis (1983), metal vapors plasma when utilizing its monitoring YAG (400W) welding aluminum alloy and stainless steel, the result shows that initial can the reaching from the peak value that audio signal records the relevant ultraviolet signal fluctuation of metal vapors plasma obtains in time domain; Audio signal when R.Dixon and G.Lewis has studied laser spot welding aluminium alloy and stainless steel, ultraviolet signal are related with weld shape and penetrability, measure the speed of metal vapors plasma with microphone, show that it is subsonic speed, along with the increase of spot welding size and penetration depth, the fluctuation of metal vapors plasma increases; Gu andDuley has designed a kind of statistical method and has monitored the laser weld state, utilizes the linear discriminent algorithm to be divided three classes, and is 83% to overheated its recall rate, and all penetrating is 67%, 75% then to be partial penetration; H.Zeng utilizes microphone identification gap joint and track misalignment, and the result shows that weld defect appears at low frequency (less than 1562Hz) Duan Bingke and real-time monitors; D.Farson etc. utilize audible sound and ultraviolet light to weld penetration monitoring, studies show that between two kinds of signals closely relatedly, utilize linear mode that welded condition is classified, and the result shows that reliability is at 88%--98%; S.Charton etc. have used the analytical method of frequency domain and time domain under study for action, comparing in the characteristic signal that extracts and the parameter library, result of study shows that the detection error depends on the size of defective, and the more little more difficult detection of defective utilizes multisensor can increase the reliability of detection; S.Postma etc. have designed a kind of feedback controller of carbon steel penetration, be mainly used in the YAG laser weld, this system is mainly based on the measurement to the molten bath optical signal, and with laser power as driver, photo-detector is the LPF analyzer of 500Hz by bandwidth, signals collecting frequency 20kHz is calculated and control by DSP; Allen Sun etc. has designed a kind of real-time detecting system of Multi-sensor Fusion, comprising infrared, ultraviolet light and audible sound sensor, calibrate AE sensor, monitors the penetration of laser weld, and has been used for CO
2The laser lap weldering.
Above-mentioned research adopts the whole bag of tricks that welding process is detected, yet does not have document that galvanized steel laser is added special weld defect in the powder welding process, does correlative study as pore.The present invention is directed to that the zinc layer easily is gasificated into a large amount of zinc fumes in the galvanized steel laser beam welding, zinc fume makes welding process easily produce multiple weld defect, as weld porosity, depression etc., on the basis of adding the generation of dissimilar metal powder inhibition zinc fume, utilize the detection in real time of welding process characteristic element plasma optical signal that galvanized steel laser is added powder welding process weld defect and carry out inline diagnosis.
Summary of the invention
Defective at prior art, the present invention aims to provide the inline diagnosis method that a kind of galvanized steel laser based on characteristic element plasma optical signal adds weld defect in the powder welding process, and this diagnostic method can be gathered the plasma optical signal powder amount of adding in the laser beam welding is carried out on-line monitoring; And can gather the plasma optical signal close with weld defect, go out the moment whether weld defect occurs and occur by the online real-time judge of the characteristic of analytic signal, in the hope of being used for the on-line monitoring of defective in the actual production laser beam welding, for the element task in early stage is done in the online quality monitoring of next step laser beam welding.
To achieve these goals, the technical solution adopted in the present invention is: described galvanized steel laser based on characteristic element plasma optical signal adds the inline diagnosis method of weld defect in the powder welding process, comprises workbench, is fixed on the galvanized steel on the workbench; Directly over described galvanized steel welding position, be provided with plumb joint, be provided with focus lamp in this plumb joint, side top, described galvanized steel welding position is provided with a plurality of light sensors, this light sensor is directly preserved the plasma optical signal of gathering and is presented in the computer by holding wire, be characterized in that laser beam focuses on the back galvanized steel is carried out laser weld; Utilize light sensor to gather galvanized steel laser simultaneously and add characteristic element plasma optical signal in the powder welding process, the characteristic element of gathering comprises the characteristic element of galvanized steel bulk material and the characteristic element of the dusty material that adds, and the on-line monitoring by characteristic element article on plasma body optical signal draws the kind of the characteristic element of material in the welding process and the addition m of character pair element; Draw related between intensity I and the weld defect of characteristic element plasma optical signal that described galvanized steel bulk material is ionized generation at last: the galvanized steel laser beam welding, do not have the welding defective and produce when the intensity I of characteristic element plasma optical signal is in dynamic stability; Produce weld defect when the rapid variation of the intensity I of characteristic element plasma optical signal or fluctuation, described weld defect comprises the depression of pore, face of weld; The addition m that adds the character pair element in the intensity I of the characteristic element plasma optical signal of the dusty material that adds and unit interval is near-linear relation: I=K1*m+K2, and wherein K1, K2 are corresponding constant; By gathering the plasma resonance light signal strength I that laser adds dusty material corresponding element in the powder welding process, the amount of powder that acquisition is added, thereby the generation of weld defect in the judgement welding process: when dusty material characteristic element plasma light signal strength increases, character pair element addition increases, thereby the welding process zinc fume is less, and weld defect produces probability and reduces; When dusty material characteristic element plasma light signal strength reduced, character pair element addition reduced, thereby the welding process zinc fume increases, and weld defect produces probability and becomes big.
The amount m span of the characteristic element that adds in the described unit interval is 1-20g/min.
Laser beam welding is in the nature a dynamic fluctuation process, have only stable dynamic fluctuation welding process just can obtain good weld seam, and the plasma optical signal of corresponding this moment also is to be in the dynamic stability fluctuation status, therefore when the corresponding element signal fluctuation is steady, do not produce weld defect, when when signal changes suddenly, producing, will produce weld defect.
The dusty material of described interpolation is copper powder, light sensor described in the welding process has been gathered the plasma optical signal of three kinds of characteristic elements simultaneously, is respectively: the ferro element plasma optical signal in the copper plasma optical signal in the dusty material, the zinc element plasma optical signal in the galvanized steel, the galvanized steel;
Adopt light sensor on-line monitoring copper powder addition: the characteristic element plasma optical signal of light sensor collection is copper plasma optical signal, corresponding copper plasma optical wavelength is respectively 510.55nm, 515.32nm and 521.82nm, and light sensor is only gathered the plasma optical signal of respective wavelength.
Adopt light sensor on-line monitoring zinc plasma optical signal: the amount of vaporization of being judged zinc by zinc plasma light signal strength, corresponding zinc plasma optical wavelength is respectively 334.5nm, 481.0nm, and light sensor is only gathered the plasma optical signal of respective wavelength.
Adopt light sensor on-line monitoring iron plasma optical signal: whether be in the generation of stable fluctuation condition diagnosing weld defect by on-line monitoring iron plasma optical signal, corresponding iron plasma optical wavelength is respectively 394.52nm, 402.45nm, and light sensor is only gathered the plasma optical signal of respective wavelength.
With the above-mentioned copper of gathering, zinc, the plasma optical signal of three kinds of characteristic elements of iron, observe three kinds of plasma optical signal variation characteristics during by plasma optical signal line real time diagnosis weld defect simultaneously: the amount of the direct corresponding zinc fume of copper plasma optical signal, whether copper plasma light signal check zinc fume is reduced, whether zinc is melted in weld seam admittedly, the minimizing of the amount of the zinc fume probability that then weld defect produces in the welding process reduces, copper powders may increase then zinc fume reduces, corresponding copper plasma optical signal strengthens, and weld defect produces probability and reduces; Air holes is in close relations in zinc plasma light signal strength and the welding process, and the diagnosable weld porosity of zinc plasma optical signal is simultaneously by the related waste that can judge welding process zinc layer of zinc plasma light signal strength with the zinc amount of element; By the variation diagnostic face of weld gas hole defect of iron plasma optical signal, comprehensively judge related between plasma optical signal and the weld defect.
The present invention is directed to galvanized steel laser and add the powder welding process.The direct laser weld of galvanized steel very easily produces weld defect, and the powder welding is added in employing can improve welding process minimizing weld defect, and whether the amount of powder of adding and weld defect have produced corresponding relation.The powder that adds such as copper powder, nickel powder, etc.The mode that powder adds is synchronous powder feeding system or adds powder in advance that wherein the synchronous powder feeding system mode can adopt two kinds of coaxial powder-feeding, side direction powder feedings.
The present invention is based on the on-line monitoring means of characteristic element plasma resonance spectral signal.Material absorbs laser energy and then fusing vaporization ionization in laser beam welding, and the plasma resonance that ionization produces goes out optical signal.The optical wavelength that the plasma resonance light of different elements is corresponding special, the amount difference of certain element plasma resonance luminous intensity difference to should element being ionized.On-line monitoring by the plasma optical signal can obtain the element kind of material in the welding process and the amount of corresponding element thus.Adopt the characteristic element plasma resonance spectral signal in the light sensor collection welding process.The characteristic of correspondence element comprises the characteristic element of galvanized steel and the characteristic element of the dusty material that adds, as: the plasma resonance spectral signal of elements such as iron, zinc, copper, nickel.
Weld defect described herein mainly comprises two kinds of special weld defects: the pore of face of weld, depression, the waste of zinc in the welding process.Prevent corrosion of steel for acting as of galvanized steel zinc coat, the minimizing of zinc must decrease to the Corrosion Protection of galvanized steel zinc coat in the welding process, and the waste of therefore monitoring zinc in the welding process also is part main purpose wherein.
The present invention adds characteristic element plasma optical signal diagnosis weld defect in the powder welding process by gathering galvanized steel laser, wherein the related two parts that mainly comprise between relevant plasma optical signal and the weld defect: the one, add the related of characteristic element plasma optical signal that dusty material is ionized generation and weld defect; The 2nd, the characteristic element plasma optical signal that the galvanized steel bulk material is ionized generation is related with weld defect.
Plasma optical signal and related one of weld defect: add dusty material and be ionized the related of the characteristic element plasma optical signal of generation and weld defect.In the galvanized steel laser beam welding, influence welding stability because the very easily gasification of zinc coat produces a large amount of zinc fumes, make welding process easily produce multiple weld defect.For solving the weld defect that produces because of zinc fume, can adopt and in welding process, add the metallurgical solid solution of material reaction formation that special elements makes zinc coat and interpolation, zinc is kept in the weld seam, reduces the generation of zinc fume, thereby reduce the weld defect that zinc fume causes.When the dusty material that adds more after a little while, be not enough to the generation of less zinc fume, a large amount of zinc fumes will have a negative impact so that various weld defects occur welding process; When the powder that adds when suitable, dusty material is solidificated in zinc in the weld seam, has reduced corresponding weld defect thereby reduced zinc fume; When the amount of powder of adding is too much, will have rolled up the xenogenesis element in the weld seam and make the mechanical performance of weld seam change.Hence one can see that, there is indirect association in the weld defect that the amount of powder of adding in the welding process and welding process produce, and having only suitable powder addition just can obtain desirable welding effect, is to observe the important means that whether obtains desirable welding effect to the monitoring of the amount of powder of adding.If add in the powder welding process at laser and to adopt synchronous powder feeding system, its powder feed rate that dust feeder control can be arranged, but the actual powder amount that is sent to the welding position is a uncertain undulating value.Therefore the real time on-line monitoring to the addition of powder in the welding process is a kind of feasible method of diagnosing weld defect indirectly.Be the effective ways of realizing powder addition on-line monitoring based on characteristic element plasma resonance optical signal and adopt foregoing, as shown in Figure 4, we have drawn the powder addition and there is a linear relationship in the plasma light signal strength on the bases of a large amount of experiments.Add in the powder welding process plasma resonance light signal strength of corresponding element in the dusty material by gathering laser, can judge the amount of powder of adding, thereby judge the welding process generation of defects indirectly.
In the galvanized steel laser weld, the vapor volume of zinc reduces the reduction that is conducive to weld defect generation probability, the solid solution that adds the generation of material copper and zinc can directly reduce the evaporation of zinc, thereby copper plasma optical signal strengthens the reduction that produces probability corresponding to weld defect; Zinc plasma optical signal big ups and downs can occur when producing the welding pore, shown in Fig. 5,6, test shows at crest and the trough place of the big ups and downs of zinc plasma optical signal all might produce the welding pore, and it is bigger to produce the probability that welds pore when crest.Related similar in appearance to zinc plasma and welding pore of the variation of iron plasma optical signal and face of weld gas hole defect related, when producing the welding pore can big ups and downs appear iron plasma optical signal, crest and trough place in the signal big ups and downs all might produce the welding pore, and it is bigger to produce the probability that welds pore when crest.
The pass di-of plasma optical signal and weld defect:
The characteristic element plasma optical signal that the galvanized steel bulk material is ionized generation is related with weld defect.Zinc plasma optical signal big ups and downs can occur when producing the welding pore, test shows at crest and the trough place of the big ups and downs of zinc plasma optical signal all might produce the welding pore, and the probability that produces the welding pore when crest is bigger, shown in Fig. 5,6.Related similar in appearance to zinc plasma and welding pore of the variation of iron plasma optical signal and face of weld gas hole defect related, when producing the welding pore can big ups and downs appear iron plasma optical signal, crest and trough place in the signal big ups and downs all might produce the welding pore, and it is bigger to produce the probability that welds pore when crest.
The present invention is a kind of method of adding powder welding process on-line monitoring and diagnosis weld defect for actual production galvanized steel laser, can judge directly whether weld defect produces by the real-time plasma optical signal in the monitoring welding process, and the period of weld defect generation, in the hope of being used for the on-line monitoring of defective in the actual production laser beam welding, for the element task in early stage is done in the online quality monitoring of next step laser beam welding.
Compared with prior art, the invention has the beneficial effects as follows: the present invention has realized utilizing collection plasma optical signal that the powder amount of adding in the laser beam welding is carried out on-line monitoring; And the close plasma optical signal of collection and weld defect, the online real-time judge of characteristic by analytical characteristic element article on plasma body optical signal goes out the moment whether weld defect occurs and occur, to be used for the on-line monitoring of defective in the actual production laser beam welding, for the element task in early stage is done in the online quality monitoring of next step laser beam welding.
Description of drawings
The invention will be further described below in conjunction with drawings and Examples.
Fig. 1 is the described powder schematic diagram that adds in advance of the present invention;
Fig. 2 is described synchronous powder feeding system schematic diagram of the present invention;
Fig. 3 is the structure structural map of device of the present invention;
Fig. 4 is the associated diagram of plasma spectrometry signal strength signal intensity of the present invention and characteristic element amount;
Fig. 5 is the pictorial diagram that the present invention welds weld seam positive and negative, back;
Fig. 6 is zinc the intensity of spectral line signal graph of the present invention's correspondence when welding.
In the drawings
The 1-galvanized steel; The 2-plumb joint; The 4-light sensor; The 5-computer.
The specific embodiment
Present embodiment adopts experimental rig as shown in Figure 3, and this device comprises workbench, is fixed on the galvanized steel 1 on the workbench; Directly over described galvanized steel 1 welding position, be provided with plumb joint 2, be provided with focus lamp in this plumb joint 2, above this plumb joint 2, be provided with one and be the speculum of an angle with horizontal direction, side top, described galvanized steel 1 welding position is provided with a plurality of light sensors 4, and this light sensor 4 is used for preserving by optical fiber and one and shows that the computer 5 of the plasma optical signal of gathering links to each other.Laser beam focuses on vertical irradiation at surface of the work by corresponding laser instrument output, and focal position is at material surface.Workbench is controlled by corresponding Digit Control Machine Tool.The laser weld galvanized steel is the welding arrangement form of joint form, and thickness of slab is 0.8-1.6mm, does not have the gap between plate.As illustrated in fig. 1 and 2, the mode that powder adds is for adding powder or synchronous powder feeding system in advance, and the side direction in the present embodiment employing synchronous powder feeding system mode is as shown in Figure 2 sent branch, and powder is sent into the welding position by light beam the place ahead.The plasma light signal collection adopts light sensor, sensor to be positioned at top, welding position and laser beam at angle, gathers the plasma optical signal from welding aperture top.Light sensor the corresponding wavelength of gathering, sensor arrange height and angle and number of sensors, by decisions such as the number of signals of the element spectral wavelength of the required collection of reality and required collection, signal powers.The plasma optical signal of gathering is preserved and is presented in the computer 5.
Utilize light sensor 4 to gather galvanized steels 1 laser and add three kinds of characteristic element plasma optical signals in the powder welding process, be respectively: the ferro element plasma optical signal in the copper plasma optical signal in the dusty material, the zinc element plasma optical signal in the galvanized steel 1, the galvanized steel 1; The characteristic element of gathering comprises the characteristic element of galvanized steel 1 and the characteristic element of the dusty material that adds, and the on-line monitoring by three kinds of characteristic element article on plasma body optical signals draws the kind of the characteristic element of material in the welding process and the amount m of character pair element; Draw related between characteristic element plasma optical signal and the weld defect at last, wherein said weld defect comprises the waste of zinc in pore, depression and the welding process of face of weld; Described galvanized steel bulk material is ionized intensity I and described weld defect related of the characteristic element plasma optical signal of generation; The intensity I of the characteristic element plasma optical signal of the dusty material that adds as shown in Figure 4, and the amount m of character pair element are linear: I=K
1* m+K
2, wherein K1, K2 are corresponding coefficient, the m span is 1-20g/min.
Form the solid solution of zinc and copper because being added in galvanized steel 1 laser beam welding of copper powder, zinc and copper can react, reduced the pore in the weld seam thereby reduced zinc fume.The powder feed rate control of copper powder is controlled roughly by powder feeder, and the actual amount of powder of welding process of adding to is by the light sensor on-line monitoring.
The collection of welding process ionic medium body optical signal, gathered the plasma optical signal of three kinds of characteristic elements simultaneously, be respectively: the copper plasma optical signal in the dusty material, zinc coat zinc element plasma optical signal, steel of base metal iron matrix element plasma optical signal.
1, adopt light sensor on-line monitoring copper powder addition: the characteristic element plasma optical signal that light sensor is gathered is copper plasma optical signal, corresponding copper plasma optical wavelength is 510.55nm, 515.32nm and 521.82nm, and therefore needed light sensor is only gathered the plasma optical signal of respective wavelength.
2, adopt light sensor on-line monitoring zinc plasma optical signal: if zinc fume reduces then the corresponding zinc plasma that is ionized generation must reduce in welding process, can judge the amount of vaporization of zinc thus by zinc plasma light signal strength.Corresponding zinc plasma optical wavelength is 334.5nm, 481.0nm, and thus, light sensor is only gathered the plasma optical signal of respective wavelength.
3, adopt light sensor on-line monitoring iron plasma optical signal: the iron plasma is in the dynamic steady state of cyclic swing in stable laser beam welding, if iron plasma optical signal leaves and stablizes fluctuation status then can judge that unsteady state has appearred in welding process, non-stable welding process must cause corresponding weld defect, so whether on-line monitoring iron plasma is in and stablizes the generation that fluctuation status can be diagnosed certain weld defect equally.The plasma optical wavelength of ferro element is 394.52nm, 402.45nm,, light sensor is only gathered the plasma optical signal of respective wavelength.More than needed light sensor fast signals collecting frequency must be arranged enough, to obtain continuous signal variation characteristic, its frequency acquisition is not less than 100Hz.
More than gathered the plasma optical signal of three kinds of characteristic elements, the variation characteristic of every kind of characteristic element plasma optical signal is different with degree in close relations between certain specific weld defective produces.The amount of the direct corresponding zinc fume of copper plasma optical signal, what of zinc fume produce multiple adverse effect to welding process, the welding process that makes produces multiple weld defect, so unsuitable directly corresponding certain weld defect of the inspection of copper plasma optical signal, it mainly acts on is to check whether zinc fume is reduced, and whether zinc is cured in the weld seam.Inspection for zinc plasma optical signal then can direct corresponding weld defect.As Fig. 5, shown in 6, the signal of gathering is the zinc element wavelength in the galvanized steel laser beam welding changes corresponding face of weld pore for the 334.5nm light signal strength result of the test figure.The generation that can find out zinc plasma light signal strength and surface pores is in close relations, by the diagnosable face of weld pore of zinc plasma optical signal.Zinc plasma light signal strength can directly have been used the waste of judging welding process zinc layer with the related of zinc amount of element simultaneously.The effect of ferro element plasma optical signal and zinc element plasma optical signal diagnosis face of weld pore effect are similar, because in laser beam welding the generation of surface pores be since in the welding aperture metal vapors weld seam molten bath taken away when outwards spraying and forms pore, depression, in the steam of ejection zinc and ferro element are arranged simultaneously, the zinc of correspondence and the plasma optical signal of iron had similar variation when pore produced, and the variation of iron plasma optical signal can be used to diagnose the face of weld gas hole defect equally.Because there is jumping phenomenon unavoidably in various signals in the actual welding process, adopt single signal diagnosis welding process to exist and hide inaccuracy, therefore by plasma optical signal line real time diagnosis weld defect the time, need observe three kinds of plasma optical signal variation characteristics simultaneously, comprehensively judge related between plasma optical signal and the weld defect.
Claims (4)
1. inline diagnosis method that the galvanized steel laser based on characteristic element plasma optical signal adds weld defect in the powder welding process, its device comprises workbench, is fixed on the galvanized steel (1) on the workbench; Directly over described galvanized steel (1) welding position, be provided with plumb joint (2), this plumb joint is provided with focus lamp in (2), the powder device that adds synchronously that galvanized steel laser adds the powder welding is fixed on the plumb joint (2), side top, described galvanized steel (1) welding position is provided with a plurality of light sensors (4), and this light sensor (4) is directly preserved the plasma optical signal of gathering and is presented in the computer (5) by holding wire; It is characterized in that laser beam focuses on the back galvanized steel (1) is carried out laser weld; Utilize light sensor (4) to gather galvanized steel (1) laser simultaneously and add characteristic element plasma optical signal in the powder welding process, the characteristic element of gathering comprises the characteristic element of galvanized steel (1) bulk material and the characteristic element of the dusty material that adds, and the on-line monitoring by characteristic element article on plasma body optical signal draws the kind of the characteristic element of material in the welding process and the addition m of character pair element; Draw related between intensity I and the weld defect of characteristic element plasma optical signal that described galvanized steel bulk material is ionized generation at last: galvanized steel (1) laser beam welding, do not have the welding defective and produce when the intensity I of characteristic element plasma optical signal is in dynamic stability; Produce weld defect when the rapid variation of the intensity I of characteristic element plasma optical signal or fluctuation, described weld defect comprises the depression of pore, face of weld; The addition m that adds the character pair element in the intensity I of the characteristic element plasma optical signal of the dusty material that adds and unit interval is near-linear relation: I=K1*m+K2, and wherein K1, K2 are corresponding constant; By gathering the plasma light signal strength I that laser adds dusty material corresponding element in the powder welding process, the amount of powder that acquisition is added, thereby the generation of weld defect in the judgement welding process: when dusty material characteristic element plasma light signal strength increased, weld defect produced probability and reduces; When dusty material characteristic element plasma light signal strength reduced, weld defect produced probability and increases.
2. inline diagnosis method according to claim 1, it is characterized in that, the dusty material of described interpolation is copper powder, light sensor described in the welding process (4) has been gathered the plasma optical signal of three kinds of characteristic elements simultaneously, is respectively: the ferro element plasma optical signal in the copper plasma optical signal in the dusty material, the zinc element plasma optical signal in the galvanized steel (1), the galvanized steel (1);
Adopt light sensor (4) on-line monitoring copper powder addition: the characteristic element plasma optical signal that light sensor (4) is gathered is copper plasma optical signal, and light sensor (4) is only gathered the plasma optical signal of copper specific wavelength;
Adopt light sensor (4) on-line monitoring zinc plasma optical signal: the amount of vaporization of being judged zinc by zinc plasma light signal strength, corresponding zinc plasma optical wavelength is respectively 334.5nm, 481.0nm, and light sensor (4) is only gathered the plasma optical signal of respective wavelength;
Adopt light sensor (4) on-line monitoring iron plasma optical signal: whether be in the generation of stable fluctuation condition diagnosing weld defect by on-line monitoring iron plasma optical signal, corresponding iron plasma optical wavelength is respectively 394.52nm, 402.45nm, and light sensor (4) is only gathered the plasma optical signal of respective wavelength;
The plasma optical signal of the above-mentioned copper of gathering, zinc, three kinds of characteristic elements of iron, but by observing three kinds of plasma optical signal variation characteristic line real time diagnosis weld defects: the vapor volume that copper plasma optical signal strengthens corresponding to zinc reduces, the vapor volume of zinc reduces the reduction that produces probability corresponding to weld defect, so copper plasma optical signal strengthens the reduction that produces probability corresponding to weld defect; Big ups and downs appear in zinc element plasma optical signal, all might produce the welding pore at crest and the trough place of signal big ups and downs, and it is bigger to produce the probability that welds pore when crest; Big ups and downs appear in ferro element plasma optical signal, all might produce the welding pore at crest and the trough place of signal big ups and downs, and it is bigger to produce the probability that welds pore when crest.
3. inline diagnosis method according to claim 1 and 2 is characterized in that, the frequency acquisition of described light sensor (4) is not less than 100Hz.
4. inline diagnosis method according to claim 1 and 2 is characterized in that, the amount m span of adding the character pair element in the described unit interval is 1-20g/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010553902 CN102049613B (en) | 2010-11-18 | 2010-11-18 | Online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on characteristic element plasma optical signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010553902 CN102049613B (en) | 2010-11-18 | 2010-11-18 | Online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on characteristic element plasma optical signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102049613A CN102049613A (en) | 2011-05-11 |
| CN102049613B true CN102049613B (en) | 2013-08-28 |
Family
ID=43954593
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201010553902 Active CN102049613B (en) | 2010-11-18 | 2010-11-18 | Online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on characteristic element plasma optical signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102049613B (en) |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102615423B (en) * | 2012-04-25 | 2014-04-02 | 湖南大学 | Method for diagnosing galvanized steel laser powder addition welding defects on line based on characteristic spectrum |
| CN103878479B (en) * | 2014-03-06 | 2016-02-10 | 上海交通大学 | The online test method in the T-shaped lap joint gap of the Laser Welding based on spectrum analysis |
| CN108406112B (en) * | 2015-02-09 | 2021-07-27 | 通快激光英国有限公司 | Laser weld |
| CN106312310B (en) * | 2015-07-01 | 2018-05-08 | 湖南大学 | Laser welding optimization method and its device based on Laser induced plasma spectroscopy |
| CN105215551B (en) * | 2015-08-17 | 2017-07-18 | 上海航天精密机械研究所 | Hybrid Laser-Arc Welding synergistic enhancing effect online test method and device |
| CN105414762B (en) * | 2015-12-30 | 2017-10-03 | 哈尔滨工业大学 | A kind of laser connection method based on laser gain material manufacturing technology |
| CN105651786A (en) * | 2016-02-04 | 2016-06-08 | 上海航天精密机械研究所 | Online quality monitoring method and device for laser cutting process |
| CN108375581B (en) * | 2017-01-04 | 2020-08-04 | 中国航空制造技术研究院 | Double-beam laser welding process defect control method based on acousto-optic signal monitoring |
| CN106907994B (en) * | 2017-03-13 | 2018-12-25 | 湖南大学 | A method of measurement weld seam melts volume |
| CN108875113B (en) * | 2017-09-07 | 2021-06-11 | 湖南大学 | Penetration prediction and control method and system for variable-thickness cross-section plate laser welding |
| CN108680502B (en) * | 2018-04-19 | 2020-09-04 | 广州德擎光学科技有限公司 | Laser processing state monitoring device based on spectrum selection region reconstruction multiphase characteristics |
| JP6799038B2 (en) | 2018-08-24 | 2020-12-09 | ファナック株式会社 | Laser processing system, jet observation device, laser processing method, and jet observation method |
| CN109079351A (en) * | 2018-09-03 | 2018-12-25 | 广东工业大学 | Laser welding based on the demodulation of coaxial optical radiation signal is partially welded detection method and device |
| CN110000473A (en) * | 2019-05-14 | 2019-07-12 | 广东工业大学 | A kind of galvanized steel laser adds powder welding defect online monitoring system and method |
| US20210341451A1 (en) * | 2020-03-30 | 2021-11-04 | Hitachi Rail S.P.A. | Method and system for monitoring and identifying the weld quality on metallic components |
| CN113996953B (en) * | 2020-07-28 | 2023-08-11 | 宝山钢铁股份有限公司 | State data comprehensive acquisition and analysis system of laser welder |
| CN114178699B (en) * | 2022-01-04 | 2024-04-19 | 江苏科技大学 | Dissimilar metal laser cladding welding device and method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2650884Y (en) * | 2003-11-21 | 2004-10-27 | 北京工业大学 | Multilayer-structure coaxial powder feeding head for laser material machining |
| CN1586786A (en) * | 2004-07-09 | 2005-03-02 | 北京工业大学 | Aluminium alloy laser welding method by powder reinforced absorption |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09192861A (en) * | 1996-01-11 | 1997-07-29 | Nissan Motor Co Ltd | Method and device for quality assurance of cladding by welding part |
| JP4026421B2 (en) * | 2002-06-18 | 2007-12-26 | 日産自動車株式会社 | Metal powder supply start timing determining apparatus and method |
-
2010
- 2010-11-18 CN CN 201010553902 patent/CN102049613B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2650884Y (en) * | 2003-11-21 | 2004-10-27 | 北京工业大学 | Multilayer-structure coaxial powder feeding head for laser material machining |
| CN1586786A (en) * | 2004-07-09 | 2005-03-02 | 北京工业大学 | Aluminium alloy laser welding method by powder reinforced absorption |
Non-Patent Citations (8)
| Title |
|---|
| 《填充粉末对铝合金高功率CO2激光焊接的影响》;张盛海等;《中国激光》;20050630;第32卷(第6期);全文 * |
| 《镀锌钢板激光焊接关键技术研究》;张屹等;《激光与光电子学进展》;20100730(第7期);全文 * |
| 《高强镀锌钢的CO2激光焊接研究》;申晓龙等;《湖南工业职业技术学院学报》;20061231;第6卷(第4期);全文 * |
| JP特开2004-17109A 2004.01.22 |
| JP特开平9-192861A 1997.07.29 |
| 张屹等.《镀锌钢板激光焊接关键技术研究》.《激光与光电子学进展》.2010,(第7期), |
| 张盛海等.《填充粉末对铝合金高功率CO2激光焊接的影响》.《中国激光》.2005,第32卷(第6期), |
| 申晓龙等.《高强镀锌钢的CO2激光焊接研究》.《湖南工业职业技术学院学报》.2006,第6卷(第4期), |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102049613A (en) | 2011-05-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102049613B (en) | Online diagnosis method for welding defects in laser powder-adding welding process of galvanized steel based on characteristic element plasma optical signal | |
| CN102615423B (en) | Method for diagnosing galvanized steel laser powder addition welding defects on line based on characteristic spectrum | |
| JP3603843B2 (en) | Laser welding quality monitoring method and apparatus | |
| Pal et al. | Investigation on arc sound and metal transfer modes for on-line monitoring in pulsed gas metal arc welding | |
| Zhu et al. | Energy characteristics of droplet transfer in wire-arc additive manufacturing based on the analysis of arc signals | |
| CN103878479B (en) | The online test method in the T-shaped lap joint gap of the Laser Welding based on spectrum analysis | |
| CN1083975C (en) | Method and apparatus for arc-light sensing the working of plasma arc welding small hole | |
| CN101328584A (en) | Laser cladding real time monitoring system | |
| CN108802165A (en) | Have the increasing material system of processing and method of spectrum ULTRASONIC COMPLEX on-line checking function | |
| Sun et al. | Monitoring of laser weld penetration using sensor fusion | |
| US8063340B2 (en) | Method for controlling the consistency of an arc welding process by monitoring welding voltage to determine weld droplet detachment | |
| EP2543464A2 (en) | Apparatus for laser beam welding and method for controlling quality of weld | |
| Nakamura et al. | Detection technique for transition between deep penetration mode and shallow penetration mode in CO2 laser welding of metals | |
| Farson et al. | Frequency–time characteristics of air‐borne signals from laser welds | |
| Sanders et al. | Real-time monitoring of laser beam welding using infrared weld emissions | |
| CN108237322B (en) | Real-time monitoring device and method for quality of electron beam dynamic welding seam | |
| Ancona et al. | A sensing torch for on-line monitoring of the gas tungsten arc welding process of steel pipes | |
| Gao et al. | Synchronized monitoring of droplet transition and keyhole bottom in high power laser-MAG hybrid welding process | |
| JP6688021B2 (en) | Laser welding monitoring device and laser welding monitoring method | |
| CN109128446B (en) | Method for rapidly extracting characteristics of arc sound signals of alternating-current tungsten electrode argon arc welding | |
| Zhao et al. | GMAW metal transfer mode identification from welding sound | |
| Cai et al. | Physical mechanism of laser-excited acoustic wave and its application in recognition of incomplete-penetration welding defect | |
| JPH08281456A (en) | Method for detecting penetration of laser beam welding and device thereof | |
| Yusof et al. | Acoustic methods in real-time welding process monitoring: Application and future potential advancement | |
| Polajnar et al. | ARC welding process monitoring by audible sound |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |