CN104614444B - Method for improving electromagnetic ultrasonic detection precision - Google Patents
Method for improving electromagnetic ultrasonic detection precision Download PDFInfo
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- CN104614444B CN104614444B CN201510084233.9A CN201510084233A CN104614444B CN 104614444 B CN104614444 B CN 104614444B CN 201510084233 A CN201510084233 A CN 201510084233A CN 104614444 B CN104614444 B CN 104614444B
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Abstract
The invention discloses a method for improving electromagnetic ultrasonic detection precision. By adopting an unequal amplitude serial pulse excitation calibration method, a relative change rule of an ultrasonic bottom wave signal amplitude of a metal workpiece with magnetic conductivity, conductivity and non-uniform surface in electromagnetic ultrasonic detection is obtained so as to inhibit signal attenuation caused by changes of magnetic conductivity, conductivity and surface state in an electromagnetic ultrasonic detection signal, so that an ultrasonic defect echo signal amplitude in actual detection is equivalently compensated and corrected and the detection accuracy is improved.
Description
Art
The present invention relates to a kind of lossless detection method, more particularly to a kind of method for improving electromagnetic acoustic accuracy of detection.
Background technology
Different from transducer in conventional Ultrasound detection technique is by the piezo-electric effect transmitting of piezoelectric chip and receives ultrasonic wave, electricity
Ultrasonic wave is launched and received to transducer by galvanomagnetic-effect in magnetic ultrasonic detecting technology.When the eddy current coil being placed on surface of the work leads to
When crossing high frequency electric, vortex is produced in the skin superficial layer that becomes of workpiece, this vortex will produce high frequency vibrating in the presence of externally-applied magnetic field
It is dynamic, define ultrasonic source.When ultrasonic wave is received, the concussion of surface of the work also can be in the presence of externally-applied magnetic field, in whirlpool
Induce voltage and received by instrument in streamline circle.In the above-mentioned methods, transducer has been not merely the whirlpool of logical alternating current
Streamline circle and the assembly in external stability magnetic field, tested metal works are also an important component part of transducer, electricity and
The conversion of sound is completed jointly by eddy current coil, magnet and tested metal works.
Magnetic conductivity is the physical quantity for representing magnetizing mediums magnetic, equal to magnetic induction intensity in magnetizing mediums and the ratio of magnetic field intensity.
Due to the impact of the conditions such as the chemical composition of examined workpiece material, condition of heat treatment and temperature, material internal magnetic conductivity everywhere
There is nuance.In addition, during for ferrimagnet workpiece sensing, detection zone need to be magnetized into into saturation with magnetizing assembly,
Magnetic conductivity is set to become for a constant, but in actual application, it is more difficult to accomplish fully saturated magnetization, cause material internal everywhere
There are minor variations in magnetic conductivity.When detection coil is placed on workpiece diverse location during actually detected, the defect letter for detecting
It is number variant.Find that the minor variations of magnetic conductivity can cause noise signal in workpiece, cause detection signal to be believed through experimental study
Make an uproar than low, limit the extensive application of electromagnetic acoustic technology.Additionally, electrical conductivity, uneven, the gap change in surface etc. all can cause
The change of electromagnetic ultrasonic transducer sensitivity.
The content of the invention
It is an object of the invention to overcome the deficiency of prior art, there is provided a kind of side of raising electromagnetic acoustic accuracy of detection
Method, using non-constant amplitude series of pulses scaling method is encouraged, and obtains magnetic conductivity, electrical conductivity, surface in electromagnetic acoustic detection uneven
Metal works ultrasonic bottom ripple signal amplitude with respect to Changing Pattern, the magnetic conductance in electromagnetic acoustic detection signal is suppressed with this
The signal attenuation that rate, electrical conductivity, surface state change cause, Flaw Echo Signal in Ultrasonic Testing when equivalent compensating approach is actually detected
Amplitude.
The technical solution adopted for the present invention to solve the technical problems is：A kind of side for improving electromagnetic acoustic accuracy of detection
Method, using non-constant amplitude series of pulses scaling method is encouraged, and obtains magnetic conductivity or electrical conductivity or surface inequality in electromagnetic acoustic detection
The ultrasonic bottom ripple signal amplitude of even metal works suppresses the magnetic conductance in electromagnetic acoustic detection signal with this with respect to Changing Pattern
The signal attenuation that three kinds of Parameters variations of rate or electrical conductivity or surface state cause, ultrasound when equivalent compensating approach is actually detected lacks
Sunken echo-signal amplitude, improves accuracy in detection, and methods described has demarcation and surveys two processes,
The calibration process is,
A. control sample is made, the control sample is identical with the material of tested metal works, shape；
B. the test point on control sample surface electromagnetic ultrasonic detection probe being placed in after magnetization, this is detected
Point is set as referring to test point, and electromagnetic acoustic detector is visited using the excitation electromagnetic acoustic detection of non-constant amplitude series of pulses pumping signal
Head, the non-constant amplitude series of pulses pumping signal is made up of the pulse excitation signal of multiple different amplitudes；Electromagnetic acoustic is detected
Probe produces corresponding non-constant amplitude Series ultrasonic bottom ripple signal, the non-constant amplitude Series ultrasonic bottom ripple letter in control sample underexcitation
Number it is made up of the ultrasonic bottom ripple signal of multiple different amplitudes；The non-constant amplitude Series ultrasonic bottom ripple signal is detected by electromagnetic acoustic
Probe is gathered and transmitted to electromagnetic acoustic detector, and electromagnetic acoustic detector records non-constant amplitude Series ultrasonic bottom ripple signal；
C. the amplitude with non-constant amplitude series of pulses pumping signal is as abscissa, with non-constant amplitude Series ultrasonic bottom ripple signal
Amplitude is ordinate, makes the excitation-bottom curve line chart of the test point；
D. other test points electromagnetic ultrasonic detection probe being sequentially placed on control sample surface, repeat step b, step
Rapid c, produces the excitation-bottom curve line chart of each test point；
E. the excitation of all test points in comparative analysis control sample-bottom curve line chart, when test point with reference to detection
When the magnetic conductivity and electrical conductivity and all identical three kinds of parameters of surface state of point, the non-constant amplitude series of pulses pumping signal of identical will be produced
The non-constant amplitude Series ultrasonic bottom ripple signal of life identical, the excitation-bottom wave profile of the test point and the excitation-bottom ripple with reference to test point
Curves；When test point with the magnetic conductivity or electrical conductivity or surface state with reference to test point not simultaneously as magnetic conductivity or electricity
The signal attenuation that conductance or surface state difference cause, the non-constant amplitude series of pulses pumping signal of identical will produce different non-etc.
Width Series ultrasonic bottom ripple signal, the excitation-bottom wave profile of the test point is relative with the excitation-bottom wave profile with reference to test point to be occurred
Deviate；Thus, the ultrasonic bottom ripple letter of the uneven control sample difference test point of magnetic conductivity or electrical conductivity or surface state is obtained
Number amplitude is with respect to Changing Pattern；Each test point of Record Comparison sample is relative to the excitation with reference to test point-bottom wave profile
Deviation value, the deviation value is the signal attenuation value that magnetic conductivity or electrical conductivity or surface state change cause；
The actual measurement process is,
F. the test point on tested surface of workpiece electromagnetic ultrasonic detection probe being placed in after magnetization, electromagnetism
Ultrasound measuring instrument encourages electromagnetic ultrasonic detection probe, electromagnetic ultrasonic detection probe using the pulse excitation signal of a selected amplitude
Ultrasonic signal is produced in tested metal works underexcitation, when defective in tested metal works, ultrasonic Flaw echo will be produced
Signal, Flaw Echo Signal in Ultrasonic Testing now is that magnetic conductivity or electrical conductivity or surface state change cause the ultrasound after signal attenuation
Flaw echoes；Electromagnetic acoustic detector is using the test point obtained in calibration process relative to swashing with reference to test point
Encourage-bottom wave profile deviation value carries out equivalent compensating approach to Flaw Echo Signal in Ultrasonic Testing, obtains ultrasonic Flaw echo revise signal.
The invention has the beneficial effects as follows, a kind of method for improving electromagnetic acoustic accuracy of detection, using non-constant amplitude series of pulses
Excitation scaling method, obtains the ultrasonic bottom ripple letter of the uneven metal works in magnetic conductivity, electrical conductivity, surface in electromagnetic acoustic detection
Number amplitude suppresses the magnetic conductivity in electromagnetic acoustic detection signal, electrical conductivity, surface state change to draw with respect to Changing Pattern with this
The signal attenuation for rising, Flaw Echo Signal in Ultrasonic Testing amplitude when equivalent compensating approach is actually detected improves accuracy in detection.
The present invention is described in further detail with reference to embodiments, but a kind of of the present invention improves electromagnetic acoustic detection
The method of precision is not limited to embodiment.
Description of the drawings
Below in conjunction with the accompanying drawings the present invention is further described for middle embodiment.
Fig. 1 is non-constant amplitude series of pulses pumping signal and non-constant amplitude Series ultrasonic in the calibration process of the embodiment of the present invention
Bottom ripple signal schematic representation.
Fig. 2 is that the excitation-bottom wave profile diagram in the calibration process of the embodiment of the present invention is intended to.
Fig. 3 is the Flaw Echo Signal in Ultrasonic Testing amendment schematic diagram during the actual measurement of the embodiment of the present invention.
In figure, the non-constant amplitude series of pulses pumping signals of T., the non-constant amplitude Series ultrasonic bottom ripple signals of R., i. is with reference to test point
Excitation-bottom wave profile, the excitation-bottom wave profile of ii. other test points, Δ L. deviation values, VT. non-constant amplitude series of pulses excitation
Signal amplitude, VR. non-constant amplitude Series ultrasonic bottom ripple signal amplitude, K. Flaw Echo Signal in Ultrasonic Testing, K '. ultrasonic Flaw echo is repaiied
Positive signal.
Specific embodiment
Embodiment, as shown in Figure 1, Figure 2, Figure 3 shows, a kind of method of raising electromagnetic acoustic accuracy of detection of the present invention is adopted
Non- constant amplitude series of pulses encourages scaling method, obtains the uneven metal in magnetic conductivity or electrical conductivity or surface in electromagnetic acoustic detection
The ultrasonic bottom ripple signal amplitude of workpiece suppresses the magnetic conductivity or conductance in electromagnetic acoustic detection signal with this with respect to Changing Pattern
The signal attenuation that three kinds of Parameters variations of rate or surface state cause, ultrasonic Flaw echo letter when equivalent compensating approach is actually detected
Number amplitude, improves accuracy in detection, and methods described has demarcation and surveys two processes,
The calibration process is,
A. control sample is made, the control sample is identical with the material of tested metal works, shape；
B. the test point on control sample surface electromagnetic ultrasonic detection probe being placed in after magnetization, this is detected
Point is set as referring to test point, and electromagnetic acoustic detector is using the excitation electromagnetic acoustic detection of non-constant amplitude series of pulses pumping signal T
Probe, non-constant amplitude series of pulses pumping signal T is made up of the pulse excitation signal of multiple different amplitudes；Electromagnetic acoustic is examined
Probing head produces corresponding non-constant amplitude Series ultrasonic bottom ripple signal R, the non-constant amplitude Series ultrasonic bottom in control sample underexcitation
Ripple signal R is made up of the ultrasonic bottom ripple signal of multiple different amplitudes；The non-constant amplitude Series ultrasonic bottom ripple signal R is surpassed by electromagnetism
Sound detection probe is gathered and transmitted to electromagnetic acoustic detector, and electromagnetic acoustic detector records non-constant amplitude Series ultrasonic bottom ripple signal
R；
C. the amplitude with non-constant amplitude series of pulses pumping signal T is as abscissa, with non-constant amplitude Series ultrasonic bottom ripple signal R
Amplitude be ordinate, make the excitation-bottom curve line chart i of the test point；
D. other test points electromagnetic ultrasonic detection probe being sequentially placed on control sample surface, repeat step b, step
Rapid c, produces the excitation-bottom curve line chart of each test point；
E. the excitation of all test points in comparative analysis control sample-bottom curve line chart, when test point with reference to detection
When the magnetic conductivity and electrical conductivity and all identical three kinds of parameters of surface state of point, non-constant amplitude series of pulses pumping signal T of identical will
Produce the non-constant amplitude Series ultrasonic bottom ripple signal R of identical, the excitation-bottom wave profile of the test point and the excitation with reference to test point-
Bottom wave profile i is coincide；When test point with the magnetic conductivity or electrical conductivity or surface state with reference to test point not simultaneously as magnetic conductivity
Or the signal attenuation that electrical conductivity or surface state difference cause, non-constant amplitude series of pulses pumping signal T of identical will produce different
Non- constant amplitude Series ultrasonic bottom ripple signal R, excitation-bottom wave profile ii of the test point with reference to test point excitation-bottom curve
Line i is relative to be occurred deviateing；Thus, the uneven control sample difference test point of magnetic conductivity or electrical conductivity or surface state is obtained
Ultrasonic bottom ripple signal amplitude is with respect to Changing Pattern；Each test point of Record Comparison sample is relative to swashing with reference to test point
- bottom wave profile disagreement value A L is encouraged, disagreement value A L is the signal that magnetic conductivity or electrical conductivity or surface state change cause
Pad value；
The actual measurement process is,
F. the test point on tested surface of workpiece electromagnetic ultrasonic detection probe being placed in after magnetization, electromagnetism
Ultrasound measuring instrument encourages electromagnetic ultrasonic detection probe, electromagnetic ultrasonic detection probe using the pulse excitation signal of a selected amplitude
Ultrasonic signal is produced in tested metal works underexcitation, when defective in tested metal works, ultrasonic Flaw echo will be produced
Signal K, Flaw Echo Signal in Ultrasonic Testing K now is that magnetic conductivity or electrical conductivity or surface state change cause super after signal attenuation
Sound flaw echoes K；Electromagnetic acoustic detector is using the test point obtained in calibration process relative to reference to test point
Excitation-bottom wave profile disagreement value A L carries out equivalent compensating approach to Flaw Echo Signal in Ultrasonic Testing K, obtains ultrasonic Flaw echo and repaiies
Positive signal K '.
The method that above-described embodiment is only used for a kind of raising electromagnetic acoustic accuracy of detection for further illustrating the present invention, but this
Invention is not limited to embodiment, any simple modification that every technical spirit according to the present invention is made to above example,
Equivalent variations and modification, each fall within the protection domain of technical solution of the present invention.
Claims (1)
1. it is a kind of improve electromagnetic acoustic accuracy of detection method, it is characterised in that：Demarcation side is encouraged using non-constant amplitude series of pulses
Method, obtains the ultrasonic bottom ripple signal amplitude phase of the uneven metal works in magnetic conductivity or electrical conductivity or surface in electromagnetic acoustic detection
To Changing Pattern, the magnetic conductivity or electrical conductivity or three kinds of Parameters variations of surface state in electromagnetic acoustic detection signal is suppressed with this
The signal attenuation for causing, Flaw Echo Signal in Ultrasonic Testing amplitude when equivalent compensating approach is actually detected improves accuracy in detection, institute
The method of stating has demarcation and surveys two processes,
The calibration process is,
A. control sample is made, the control sample is identical with the material of tested metal works, shape；
B. the test point on control sample surface electromagnetic ultrasonic detection probe being placed in after magnetization, the test point is set
It is set to and refers to test point, electromagnetic acoustic detector encourages electromagnetic ultrasonic detection probe using non-constant amplitude series of pulses pumping signal,
The non-constant amplitude series of pulses pumping signal is made up of the pulse excitation signal of multiple different amplitudes；Electromagnetic ultrasonic detection probe
Corresponding non-constant amplitude Series ultrasonic bottom ripple signal is produced in control sample underexcitation, the non-constant amplitude Series ultrasonic bottom ripple signal is
It is made up of the ultrasonic bottom ripple signal of multiple different amplitudes；The non-constant amplitude Series ultrasonic bottom ripple signal is by electromagnetic ultrasonic detection probe
Gather and transmit to electromagnetic acoustic detector, electromagnetic acoustic detector records non-constant amplitude Series ultrasonic bottom ripple signal；
C. the amplitude with non-constant amplitude series of pulses pumping signal is as abscissa, with the amplitude of non-constant amplitude Series ultrasonic bottom ripple signal
For ordinate, the excitation-bottom curve line chart of the test point is made；
D. other test points electromagnetic ultrasonic detection probe being sequentially placed on control sample surface, repeat step b, step c,
Produce the excitation-bottom curve line chart of each test point；
E. the excitation of all test points in comparative analysis control sample-bottom curve line chart, when test point with reference to test point
When magnetic conductivity and electrical conductivity and all identical three kinds of parameters of surface state, the non-constant amplitude series of pulses pumping signal of identical will produce phase
Same non-constant amplitude Series ultrasonic bottom ripple signal, the excitation-bottom wave profile of the test point and the excitation-bottom wave profile with reference to test point
It coincide；When test point with the magnetic conductivity or electrical conductivity or surface state with reference to test point not simultaneously as magnetic conductivity or electrical conductivity
Or the signal attenuation that surface state difference causes, the non-constant amplitude series of pulses pumping signal of identical will the different non-constant amplitude systems of generation
The ultrasonic bottom ripple signal of row, the excitation-bottom wave profile of the test point is relative with the excitation-bottom wave profile with reference to test point to be occurred partially
From；Thus, the ultrasonic bottom ripple signal of the uneven control sample difference test point of magnetic conductivity or electrical conductivity or surface state is obtained
Amplitude is with respect to Changing Pattern；Each test point of Record Comparison sample is inclined relative to the excitation with reference to test point-bottom wave profile
From value, the deviation value is the signal attenuation value that magnetic conductivity or electrical conductivity or surface state change cause；
The actual measurement process is,
F. the test point on tested surface of workpiece electromagnetic ultrasonic detection probe being placed in after magnetization, electromagnetic acoustic
Detector encourages electromagnetic ultrasonic detection probe using the pulse excitation signal of a selected amplitude, and electromagnetic ultrasonic detection probe is in quilt
Inspection metal works underexcitation produces ultrasonic signal, when defective in tested metal works, will produce Flaw Echo Signal in Ultrasonic Testing,
Flaw Echo Signal in Ultrasonic Testing now is that magnetic conductivity or electrical conductivity or surface state change cause the ultrasonic Flaw after signal attenuation
Echo-signal；Electromagnetic acoustic detector is using the test point obtained in calibration process relative to the excitation-bottom with reference to test point
Wave profile deviation value carries out equivalent compensating approach to Flaw Echo Signal in Ultrasonic Testing, obtains ultrasonic Flaw echo revise signal.
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| CN113804729A (en) * | 2020-06-15 | 2021-12-17 | 深圳市人民医院 | Multifunctional detection system and method |
| CN111781274B (en) * | 2020-07-22 | 2023-07-11 | 长沙理工大学 | Surface leakage wave ultrasonic imaging method based on block scanning and attenuation compensation |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101149358A (en) * | 2007-11-05 | 2008-03-26 | 钢铁研究总院 | Train wheel surface automatic electromagnetic supersonic detection device and method |
| US7353709B2 (en) * | 2005-07-06 | 2008-04-08 | National Research Council Of Canada | Method and system for determining material properties using ultrasonic attenuation |
| CN101354380A (en) * | 2007-07-23 | 2009-01-28 | 北京航空航天大学 | Vortex flow and electromagnetic ultrasonic combined type nondestructive detection method |
| CN101446571A (en) * | 2008-12-22 | 2009-06-03 | 中国广东核电集团有限公司 | Nondestructive detecting device and detecting system |
| CN102798667A (en) * | 2012-08-16 | 2012-11-28 | 山东省科学院激光研究所 | Metal defect detection method of laser-electromagnetic ultrasonic nondestructive testing system |
| CN103353479A (en) * | 2013-06-28 | 2013-10-16 | 厦门大学 | Electromagnetic ultrasonic longitudinal guided wave and magnetic leakage detection compounded detection method |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3727933B2 (en) * | 2003-05-12 | 2005-12-21 | 核燃料サイクル開発機構 | Electromagnetic ultrasonic probe |
| JP2005077298A (en) * | 2003-09-02 | 2005-03-24 | Ebara Corp | Electromagnetic ultrasonic probe, damage progression degree evaluation method and damage progression degree evaluation device of conductive material, and axial force measuring method and axial force measuring device of fastening bolt or rivet |
| JP2008545123A (en) * | 2005-07-06 | 2008-12-11 | ナショナル・リサーチ・カウンシル・オブ・カナダ | Method and system for determining material properties using ultrasonic attenuation |
| DE102008054250A1 (en) * | 2008-10-24 | 2010-04-29 | Institut Dr. Foerster Gmbh & Co. Kg | Electromagnetic-acoustic transducer and ultrasonic test system with it |
-
2015
- 2015-02-16 CN CN201510084233.9A patent/CN104614444B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7353709B2 (en) * | 2005-07-06 | 2008-04-08 | National Research Council Of Canada | Method and system for determining material properties using ultrasonic attenuation |
| CN101354380A (en) * | 2007-07-23 | 2009-01-28 | 北京航空航天大学 | Vortex flow and electromagnetic ultrasonic combined type nondestructive detection method |
| CN101149358A (en) * | 2007-11-05 | 2008-03-26 | 钢铁研究总院 | Train wheel surface automatic electromagnetic supersonic detection device and method |
| CN101446571A (en) * | 2008-12-22 | 2009-06-03 | 中国广东核电集团有限公司 | Nondestructive detecting device and detecting system |
| CN102798667A (en) * | 2012-08-16 | 2012-11-28 | 山东省科学院激光研究所 | Metal defect detection method of laser-electromagnetic ultrasonic nondestructive testing system |
| CN103353479A (en) * | 2013-06-28 | 2013-10-16 | 厦门大学 | Electromagnetic ultrasonic longitudinal guided wave and magnetic leakage detection compounded detection method |
Non-Patent Citations (6)
| Title |
|---|
| A new magnetic configuration for a small in-plane electromagnetic acoustic transducer applied to laser-ultrasound measurements:Modelling and validation;B.Dutton.et al;《Sensors & Actuators A Physical》;20051010;第125卷(第2期);第249-259页 * |
| Detection of cracks in metal sheets using pulsed laser generated ultrasound and EMAT detection;S.Dixon.et al;《Ultrasonics》;20100507;第51卷(第1期);第7-16页 * |
| Enhancement of laser-ultrasound/electromagnetic-acoustic transducer signals from Rayleigh wave interaction at surface features;S.Boonsang.et al;《Aplied Physics Letters》;20030506;第82卷(第19期);第3348-3350页 * |
| 低频电磁/涡流无损检测技术的研究;林俊明;《无损探伤》;20020228(第1期);第30-32页 * |
| 导电结构涡流/超声检测与评估技术的研究;李国厚;《中国博士学位论文全文数据库信息科技辑》;20120715(第07期);全文 * |
| 电磁超声检测技术的研究;张路遥;《中国优秀硕士学位论文全文数据库工程科技Ⅱ辑》;20111215(第S2期);全文 * |
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