CN106513290A - Transducer and method for improving electromagnetic acoustic signal strength - Google Patents
Transducer and method for improving electromagnetic acoustic signal strength Download PDFInfo
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- CN106513290A CN106513290A CN201611237908.XA CN201611237908A CN106513290A CN 106513290 A CN106513290 A CN 106513290A CN 201611237908 A CN201611237908 A CN 201611237908A CN 106513290 A CN106513290 A CN 106513290A
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- magnet
- measured
- test specimen
- coil
- magnetic field
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/04—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with electromagnetism
- B06B1/045—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with electromagnetism using vibrating magnet, armature or coil system
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/34—Generating the ultrasonic, sonic or infrasonic waves, e.g. electronic circuits specially adapted therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
- G01N2291/0234—Metals, e.g. steel
Abstract
The invention provides a transducer and method for improving the electromagnetic acoustic signal strength. The transducer comprises an upper guide rail, an upper screw rod, a coil, an upper magnet, an upper fixing base, an upper slide block, a to-be-tested piece, a lower guide rail, a lower screw rod, a lower magnet, a lower fixing base and a lower slide block. The magnetic field strength, in the direction perpendicular to the to-be-tested piece, in the to-be-tested piece is enhanced after being subjected to vector addition through magnetic field superposition of the two magnets, and therefore the strength of lorentz force, stimulating ultrasonic waves, in the to-be-tested piece is improved, and the strength of emissive ultrasonic wave signals is improved. The transducer can meet the requirement for online non-contact automatic scanning detection of nonferromagnetic metal plates such as aluminum plates.
Description
Technical field：
The present invention relates to electromagnetic ultrasonic non-destructive detection technique, specially a kind of transducer for improving electromagnetic ultrasonic signal intensity
And method.
Background technology：
Electromagnet ultrasonic changer (Electromagnetic acoustic transducer, abbreviation EMAT) is a kind of sharp
Send out and receive the device of ultrasound wave.The device can easily excite the ultrasound of various modes without the need for acoustic couplant, simple structure
Ripple, is capable of achieving non-cpntact measurement, therefore is extensively paid close attention to by researcher.Electromagnetic acoustic is excited in metallic conductor, generally there are two kinds of sides
Method, one kind are that, based on Lorentz force mechanism, one kind is based on magnetostriction mechanism.Electromagnet ultrasonic changer based on Lorentz force
It is generally used for the detection of non-ferromagnetic conductive material, generally by Magnet, coil and detection test specimen are constituted, and coil is arranged on to be detected
On test specimen, Magnet is arranged on above coil.During detection, apply pumping signal of bursting in transmitting coil, coil is in test specimen
On induce current vortex with pumping signal same frequency, current vortex is under the quiescent biasing the action of a magnetic field of Magnet in test specimen to be measured
Lorentz force is produced, ultrasound wave is produced in test specimen to be measured under dynamic Lorentz forces effect, the process that ultrasound wave is received is exactly super
The inverse process of sound wave excitation process.
According to the computing formula of Lorentz force：F=J×B
Wherein J is electric eddy current density, and B is biased magnetic field strength.From the computing formula of Lorentz force, signal to be improved
Intensity, can only improve exciting current or improve the intensity of bias magnetic field, but be limited to the power and coil of power amplifier
The factors such as the electric current that can bear, it is impossible to unlimited increase exciting current, when coil parameter, exciting current, coil and Magnet
One timing of lift-off height, after applying pumping signal in coil, the current vortex J that produces in aluminium sheet is certain.And work as J mono-
Regularly, want to improve signal intensity, be only improved the magnetic induction density B in quiescent biasing magnetic field, but when the intensity of magnetization reaches one
When fixed value, think that it is all very high on cost and technical difficulty to improve its magnetic induction again, while Magnet has magnetic
The problem of saturation, so depending merely on increase magnetic induction there is also limitation.Improve ultrasonic signal intensity at present generally all to lead to
Reduction lift-off height is crossed, is increased the method for coil turn realizing, but effect is not apparent.Due to electromagnetic acoustic transducing
Device has that conversion efficiency is more relatively low than the faint signal to noise ratio for causing the signal for receiving of ultrasonic signal that is relatively low, inspiring, signal is strong
Degree is weak the problems such as cause transmission range limited, on a large scale, over long distances detection bring difficulty.Therefore, it is necessary to improve electromagnetism surpass
The signal intensity of sonic transducer, increases the signal to noise ratio of detection sensitivity and ultrasonic signal, electromagnetic acoustic detection technique is obtained more
Plus be widely applied.
The content of the invention：
It is an object of the invention to provide a kind of transducer for improving electromagnetic ultrasonic signal intensity and method, are changed by improving
Can device structure, using the superimposed characteristics in magnetic field, strengthen biased magnetic field strength using double Magnet, realize in non-ferromagnetic metal material
Higher signal intensity and signal to noise ratio, the measurement sensitivity for improving transducer, the purpose of increase detection range is obtained during material detection.
The present invention is adopted the following technical scheme that：A kind of transducer for improving electromagnetic ultrasonic signal intensity, including upper rail, on
Leading screw, coil, upper magnet, upper fixed seat, top shoe, test specimen to be measured, lower guideway, lower leading screw, lower magnet, lower fixed seat and under
Slide block, the coil are arranged above test specimen to be measured and are not contacted with test specimen to be measured, and upper magnet is arranged above coil, coil
It is arranged on upper fixed seat with upper magnet, upper fixed seat is connected with top shoe, top shoe adopts worm drive, upper cunning with upper leading screw
Block is arranged on upper rail, and the upper leading screw is rotated and promotes top shoe to move along a straight line along upper rail, and top shoe drives upper magnet
Moved along upper rail with coil together, the lower magnet is arranged at below test specimen to be measured and is not contacted with test specimen to be measured, under
Magnet be arranged on lower fixed seat on, lower fixed seat is connected with sliding block, and sliding block is arranged in lower leading screw and lower guideway, it is described under
When leading screw is rotated, sliding block drives lower magnet to move along lower guideway, and upper rail installation parallel with lower guideway is described to be measured
Upper magnet above test specimen is projected with the lower magnet below test specimen to be measured in vertical direction and is overlapped, and keeps upper magnet and lower magnet
It is parallel to each other, the magnetic field that the upper magnet and lower magnet are formed is vertical with test specimen to be measured.
Further, the upper magnet is consistent with the polarised direction that lower magnet is installed.
Further, the spacing between the coil and test specimen to be measured is 0.5-1.5mm, the lower magnet and test specimen to be measured
Between spacing be 0.5-2mm.
The present invention is also adopted the following technical scheme that：A kind of method for improving electromagnetic ultrasonic signal intensity, comprises the steps：
Step one：The polarised direction that upper magnet is installed with lower magnet is consistent, bias magnetic field direction perpendicular to test specimen to be measured, on
Magnet forms closed-loop path with the bias magnetic field of lower magnet through test specimen to be measured, and magnetic field carries out vector superposed inside test specimen to be measured
Afterwards, strengthened in the magnetic field intensity on the direction of test specimen to be measured；
Step 2：Apply to burst pumping signal in coil, coil induces current vortex on test specimen to be measured, current vortex with
Upper magnet, the static magnetic field of lower magnet produce Lorentz force in test specimen to be measured, to be tested under dynamic Lorentz forces effect
Ultrasound wave is produced in part；
Step 3：Top shoe on the upside of test specimen to be measured and the sliding block of downside is controlled respectively from toward the synchronous fortune of same direction
It is dynamic, you can be scanned detection in the different position transmitting ultrasound wave of test specimen to be measured, by upper leading screw with lower leading screw with identical speed
Degree rotating in same direction, it is ensured that top shoe and sliding block do equidirectional linear motion with same speed, to keep upper magnet with
Projection of the Magnet in detection process on test specimen to be measured keeps overlapping.
The present invention has the advantages that：By the magnetic field superposition of two blocks of Magnet, the magnetic field intensity inside test specimen to be measured
Strengthened in the direction magnetic field intensity perpendicular to test specimen to be measured after vector addition.Therefore the excitation ultrasound in the test specimen to be measured
The Lorentz force intensity of ripple is improved so that the ultrasonic signal strength of transmitting is improved.Transducer of the present invention can meet aluminum
The online noncontact automatic scanning detection of the non-ferromagnetic metal sheet material such as plate.
Description of the drawings：
Fig. 1 is the overall construction drawing of the transducer that the present invention improves electromagnetic ultrasonic signal intensity.
Fig. 2 is the Distribution of Magnetic Field figure of single Magnet.
Fig. 3 is the Distribution of Magnetic Field figure of the present invention.
Fig. 4 is the oscillogram that the transducer of the usual single Magnet for adopting is excited.
Fig. 5 is the oscillogram that transducer of the present invention is excited.
Specific embodiment：
In order that the objects, technical solutions and advantages of the present invention become more apparent, it is below in conjunction with drawings and Examples, right
The present invention is further elaborated.It should be appreciated that specific embodiment described herein is only to explain the present invention, not
For limiting the present invention.
As shown in figure 1, the transducer that the present invention improves electromagnetic ultrasonic signal intensity includes upper rail 1, upper leading screw 2, coil
3, upper magnet 4, upper fixed seat 5, top shoe 6, test specimen to be measured 7, lower guideway 8, lower leading screw 9, lower magnet 10, lower fixed seat 11 and
Sliding block 12.Coil 3 is arranged above test specimen to be measured 7 and is not contacted with test specimen to be measured 7, and upper magnet 4 is arranged on coil 3
Side, coil 3 are arranged on upper fixed seat 5 with upper magnet 4, and upper fixed seat 5 is connected with top shoe 6, and top shoe 6 is adopted with upper leading screw 2
With worm drive, on upper rail 1, upper leading screw 2 is rotated and promotes top shoe 6 to move along a straight line along upper rail 1 top shoe 6,
Top shoe 6 drives upper magnet 4 and coil 3 to move along upper rail 1 together.Lower magnet 10 be arranged at below test specimen to be measured 7 and with
Test specimen to be measured 7 does not contact, and lower magnet 10 is arranged on lower fixed seat 11, and lower fixed seat 11 is connected with sliding block 12, sliding block
12 are arranged in lower leading screw 9 and lower guideway 8, and when lower leading screw 9 is rotated, sliding block 12 drives lower magnet 10 to move along lower guideway 8
It is dynamic.Upper rail 1 and 8 parallel installation of lower guideway.Before testing, the position of top shoe 6 and sliding block 12 is adjusted, by test specimen to be measured
Upper magnet 4 above in the of 7 is adjusted on same vertical line with the lower magnet 10 below test specimen to be measured 7, is kept above test specimen to be measured 7
Upper magnet 4 is parallel to each other with the lower magnet 10 below test specimen to be measured 7, and the magnetic field that formed of upper magnet 4 and lower magnet 10 with it is to be measured
Test specimen 7 is vertical.
During detection, apply pumping signal of bursting in coil 3, coil 3 induces current vortex, electric whirlpool on test specimen to be measured 7
Stream produces Lorentz force with upper magnet 4, the static magnetic field of lower magnet 10 in test specimen to be measured 7, under dynamic Lorentz forces effect
Ultrasound wave is produced in test specimen to be measured 7；By control the sliding block 12 of the top shoe 6 on the upside of test specimen to be measured 7 and downside respectively by
It is synchronized with the movement toward same direction, you can be scanned detection in the different position transmitting ultrasound wave of test specimen to be measured 7.On keeping
The projection of Magnet 4 and lower magnet 10 in detection process on test specimen to be measured 7 keeps overlapping, need upper leading screw 2 and lower leading screw 9 with
Same speed rotating in same direction, it is ensured that top shoe 6 and sliding block 12 do equidirectional linear motion with same speed.
When mounted, upper magnet 4 and lower magnet 10 project coincidence in vertical direction for upper magnet 4 and lower magnet 10, install
Polarised direction it is consistent.Namely if the N poles of upper magnet 4 in upper S poles under, then lower magnet 10 be also N poles in upper S poles under.
When Fig. 2 shows single Magnet, distribution situation of the magnetic field in test specimen to be measured with Magnet, Fig. 3 are of the present invention pair of magnetic
Distribution situation of the magnetic line of force in test specimen to be measured with Magnet during iron construction, can be seen that the magnetic line of force from lower magnet N from Fig. 2 and Fig. 3
Pole is set out, and enters the S poles of upper magnet through test specimen to be measured, then returns to the S poles of lower magnet from the N poles of upper magnet again, and formation is closed
Close loop.
Therefore, the magnetic field of upper magnet 4 and lower magnet 10 is overlapped between upper magnet 4 and lower magnet 10, in upper magnet 4
The magnetic field line perpendicular to test specimen to be measured 7 is formed between lower magnet 10, in magnetic field intensity B for being perpendicular to 7 direction of part to be tested
Become big, know that Lorentz force becomes big according to the computing formula F=J × B of Lorentz force, therefore pass to swashing for alternation in coil
After encouraging electric current, the ultrasonic amplitude for ejecting is also improved.In turn, if the S poles of upper magnet are upper, N poles under, then under
Magnet is also S poles upper, and under, the ultrasonic signal for ejecting is same for N poles, but opposite in phase.
Upper magnet 4 and coil 3 need enough lift-off spacing when mounted between test specimen to be measured 7, to ensure moving
Will not contact with test specimen to be measured 7 during dynamic, it is to avoid coil 3 and upper magnet 4 produce friction with 7 plate face of test specimen to be measured, cause line
3 electric leakage of circle, damage coil 3 or damage test specimen 7 to be measured, affect Detection results, between usual coil 3 and test specimen to be measured 7 between
Away from for 0.5-1.5mm it is optimal.Spacing between lower magnet 10 and test specimen to be measured 7 is that 0.5-2mm is optimal.
Fig. 4 is the oscillogram that excites of transducer of the single Magnet for adopting, the lift-off spacing between coil and test specimen to be measured
For 1mm, the displacement oscillogram that transducer is inspired when being fitted without lower magnet.Fig. 5 be using the embodiment of the present invention after, that is,
Produce Fig. 4 waveforms transducer on the basis of, lower magnet is installed below test specimen to be measured, between lower magnet and test specimen to be measured away from
From for 1mm when the displacement oscillogram that inspires of transducer.The signal waveform of contrast Fig. 4 and Fig. 5, after the structure using the present invention,
In the case where keeping other conditions constant, by increasing lower magnet, surpassing during the single Magnet of the ultrasonic Amplitude Ration for being inspired
The intensity of acoustical signal is greatly improved, and shows that the transducer of present invention design has launching efficiency and receiving sensitivity high,
The good advantage of signal to noise ratio.
The present invention improves the transducer of electromagnetic ultrasonic signal intensity, on the one hand, present invention offer one kind can be improved and is based on
The method of the signal intensity of the electromagnet ultrasonic changer of Lorentz force mechanism, the method are, based on magnetic field superposition theorem, to pass through
Increase by one block of Magnet in the opposite side of nonferromagnetic test specimen to be measured, the polarised direction of two pieces of Magnet placements is identical, bias magnetic field side
To the plate face perpendicular to test specimen to be measured, the bias magnetic field of two blocks of Magnet forms closed-loop path through test specimen to be measured, in test specimen to be measured
Internal superposition, the magnetic field intensity perpendicular to test specimen direction to be measured are strengthened.According to formula：F=J × B understands, in excitation electricity
In the case that the conditions such as stream, the lift-off height of magnetic field of magnets intensity, coil are constant, the direction magnetic field intensity vertical with current vortex J
Increase, the Lorentz force in test specimen to be measured will be caused to increase, therefore the ultrasonic intensity for producing is improved.
The above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, some improvement can also be made under the premise without departing from the principles of the invention, these improvement also should be regarded as the present invention's
Protection domain.
Claims (4)
1. it is a kind of improve electromagnetic ultrasonic signal intensity transducer, it is characterised in that：Including upper rail (1), upper leading screw (2), line
Circle (3), upper magnet (4), upper fixed seat (5), top shoe (6), test specimen (7) to be measured, lower guideway (8), lower leading screw (9), lower magnet
(10), lower fixed seat (11) and sliding block (12), coil (3) be arranged above test specimen to be measured (7) and with test specimen to be measured
(7) do not contact, upper magnet (4) is arranged above coil (3), coil (3) is arranged on upper fixed seat (5) with upper magnet (4),
Upper fixed seat (5) is connected with top shoe (6), and top shoe (6) adopts worm drive, top shoe (6) to be arranged on upper with upper leading screw (2)
On guide rail (1), described upper leading screw (2) rotate and promote top shoe (6) to move along a straight line along upper rail (1), in top shoe (6) drive
Magnet (4) and coil (3) are mobile along upper rail (1) together, lower magnet (10) be arranged at below test specimen to be measured (7) and with
Test specimen (7) to be measured do not contact, and lower magnet (10) is arranged on lower fixed seat (11), and lower fixed seat (11) is with sliding block (12) even
Connect, sliding block (12) is arranged in lower leading screw (9) and lower guideway (8), when described lower leading screw (9) rotate, sliding block (12) drives
Lower magnet (10) is mobile along lower guideway (8), upper rail (1) installation parallel with lower guideway (8), test specimen (7) to be measured
The upper magnet (4) of top is projected with the lower magnet (10) below test specimen to be measured (7) in vertical direction and is overlapped, and keeps upper magnet
(4) it is parallel to each other with lower magnet (10), the magnetic field that upper magnet (4) and lower magnet (10) are formed is vertical with test specimen to be measured (7).
2. the transducer of electromagnetic ultrasonic signal intensity is improved as claimed in claim 1, it is characterised in that：Upper magnet (4)
It is consistent with the polarised direction that lower magnet (10) is installed.
3. the transducer of electromagnetic ultrasonic signal intensity is improved as claimed in claim 1, it is characterised in that：Coil (3) with
Spacing between test specimen (7) to be measured is 0.5-1.5mm, and the spacing between lower magnet (10) and test specimen to be measured (7) is 0.5-
2mm。
4. it is a kind of improve electromagnetic ultrasonic signal intensity method, it is characterised in that：Comprise the steps
Step one：The polarised direction that upper magnet (4) is installed with lower magnet (10) is consistent, and bias magnetic field direction is perpendicular to test specimen to be measured
(7), upper magnet (4) forms closed-loop path with the bias magnetic field of lower magnet (10) through test specimen to be measured (7), and magnetic field is in test specimen to be measured
(7) it is internal carry out it is vector superposed after, the magnetic field intensity on the direction perpendicular to test specimen to be measured (7) is strengthened；
Step 2：Apply pumping signal of bursting in coil (3), coil (3) induces current vortex on test specimen to be measured (7), electricity
Vortex produces Lorentz force in test specimen to be measured (7) with the static magnetic field of upper magnet (4), lower magnet (10), in dynamic Lorentz
In the middle generation ultrasound wave of test specimen to be measured (7) under power effect；
Step 3：Top shoe (6) on the upside of test specimen to be measured (7) and the sliding block of downside (12) is controlled respectively from same toward same direction
Step motion, you can be scanned detection in the different position transmitting ultrasound wave of test specimen to be measured (7), by upper leading screw (2) and lower leading screw
(9) with same speed rotating in same direction, it is ensured that top shoe (6) and sliding block (12) do equidirectional straight line fortune with same speed
It is dynamic, to keep projection of the upper magnet (4) with lower magnet (10) in detection process on test specimen to be measured (7) to keep overlapping.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611237908.XA CN106513290A (en) | 2016-12-28 | 2016-12-28 | Transducer and method for improving electromagnetic acoustic signal strength |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611237908.XA CN106513290A (en) | 2016-12-28 | 2016-12-28 | Transducer and method for improving electromagnetic acoustic signal strength |
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| Publication Number | Publication Date |
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| CN106513290A true CN106513290A (en) | 2017-03-22 |
Family
ID=58338010
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611237908.XA Pending CN106513290A (en) | 2016-12-28 | 2016-12-28 | Transducer and method for improving electromagnetic acoustic signal strength |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108426948A (en) * | 2018-05-14 | 2018-08-21 | 南京航空航天大学 | A kind of electromagnet ultrasonic changer and its working method of the single mode Lamb wave of excitation |
| CN111515110A (en) * | 2020-04-25 | 2020-08-11 | 天津新星科能源技术有限公司 | Electromagnetic ultrasonic transducer with subzone superposition structure and working mode thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4380931A (en) * | 1981-04-23 | 1983-04-26 | The United States Of America As Represented By The Secretary Of The Navy | Apparatus and method for quantitative nondestructive wire testing |
| EP2395349A1 (en) * | 2010-06-08 | 2011-12-14 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Electromagnetic acoustic transducer (EMAT) system and a method for generating linear polarised transversal waves with variable predefined polarisation direction within a test piece |
| CN104122336A (en) * | 2014-07-16 | 2014-10-29 | 哈尔滨工业大学 | Electromagnetic ultrasonic surface wave transducer and design method thereof |
| CN204758617U (en) * | 2015-06-26 | 2015-11-11 | 嘉善华森木业有限公司 | Automatic detection device |
| CN206373043U (en) * | 2016-12-28 | 2017-08-04 | 南京航空航天大学 | A kind of transducer for improving electromagnetic ultrasonic signal intensity |
-
2016
- 2016-12-28 CN CN201611237908.XA patent/CN106513290A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4380931A (en) * | 1981-04-23 | 1983-04-26 | The United States Of America As Represented By The Secretary Of The Navy | Apparatus and method for quantitative nondestructive wire testing |
| EP2395349A1 (en) * | 2010-06-08 | 2011-12-14 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Electromagnetic acoustic transducer (EMAT) system and a method for generating linear polarised transversal waves with variable predefined polarisation direction within a test piece |
| CN104122336A (en) * | 2014-07-16 | 2014-10-29 | 哈尔滨工业大学 | Electromagnetic ultrasonic surface wave transducer and design method thereof |
| CN204758617U (en) * | 2015-06-26 | 2015-11-11 | 嘉善华森木业有限公司 | Automatic detection device |
| CN206373043U (en) * | 2016-12-28 | 2017-08-04 | 南京航空航天大学 | A kind of transducer for improving electromagnetic ultrasonic signal intensity |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108426948A (en) * | 2018-05-14 | 2018-08-21 | 南京航空航天大学 | A kind of electromagnet ultrasonic changer and its working method of the single mode Lamb wave of excitation |
| CN111515110A (en) * | 2020-04-25 | 2020-08-11 | 天津新星科能源技术有限公司 | Electromagnetic ultrasonic transducer with subzone superposition structure and working mode thereof |
| CN111515110B (en) * | 2020-04-25 | 2023-06-09 | 天津新星科能源技术有限公司 | Electromagnetic ultrasonic transducer with sub-domain superposition structure |
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Application publication date: 20170322 |