CN111693611A - Method and system for detecting metal subsurface defects by using laser ultrasonic - Google Patents
Method and system for detecting metal subsurface defects by using laser ultrasonic Download PDFInfo
- Publication number
- CN111693611A CN111693611A CN202010393709.8A CN202010393709A CN111693611A CN 111693611 A CN111693611 A CN 111693611A CN 202010393709 A CN202010393709 A CN 202010393709A CN 111693611 A CN111693611 A CN 111693611A
- Authority
- CN
- China
- Prior art keywords
- laser
- defect
- ultrasonic
- wave
- signal
- 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.)
- Pending
Links
- 230000007547 defect Effects 0.000 title claims abstract description 78
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 26
- 239000002184 metal Substances 0.000 title claims abstract description 26
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000001514 detection method Methods 0.000 claims abstract description 17
- 238000002604 ultrasonography Methods 0.000 claims abstract description 8
- 238000012545 processing Methods 0.000 claims description 16
- 239000000835 fiber Substances 0.000 claims description 5
- 238000007689 inspection Methods 0.000 claims description 5
- 238000010897 surface acoustic wave method Methods 0.000 claims 1
- 239000000463 material Substances 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000009659 non-destructive testing Methods 0.000 description 2
- 239000013307 optical fiber Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000007822 coupling agent Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000005476 size effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- 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
- G01N29/07—Analysing solids by measuring propagation velocity or propagation time of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B17/00—Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations
-
- 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
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/24—Probes
- G01N29/2418—Probes using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics
-
- 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
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/24—Probes
- G01N29/2437—Piezoelectric probes
-
- 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
- G01N29/44—Processing the detected response signal, 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
- G01N2291/01—Indexing codes associated with the measuring variable
- G01N2291/011—Velocity or travel time
-
- 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
-
- 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
- G01N2291/028—Material parameters
- G01N2291/02854—Length, thickness
-
- 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
- G01N2291/028—Material parameters
- G01N2291/0289—Internal structure, e.g. defects, grain size, texture
-
- 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
- G01N2291/04—Wave modes and trajectories
- G01N2291/044—Internal reflections (echoes), e.g. on walls or defects
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Optics & Photonics (AREA)
- Acoustics & Sound (AREA)
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The invention discloses a method and a system for detecting metal subsurface defects by using laser ultrasound, wherein the method comprises the following steps: s10, acting the laser on the workpiece to be measured through a galvanometer scanning system; s20, calculating the wave velocity of the laser-excited ultrasonic surface wave on the surface of the workpiece to be measured; s30, calculating the arrival time of the incident signal of the ultrasonic surface wave and the arrival time of the reflected signal after the ultrasonic surface wave passes through the defect; and S40, calculating the horizontal position of the defect and the perimeter of the boundary of the cross section of the defect according to the wave velocity of the ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of the incident signal and the arrival time of the reflected signal after the defect. The method for detecting the metal subsurface defect by using the laser ultrasonic can detect the position and the size of the defect on the metal pressing surface, and has the advantages of simple operation, high detection efficiency and high detection precision.
Description
Technical Field
The invention relates to the technical field of ultrasonic inspection, in particular to a method and a system for detecting metal subsurface defects by utilizing laser ultrasonic.
Background
Ultrasonic inspection is a nondestructive inspection method for inspecting internal defects of materials by using the difference of acoustic properties of the materials and the defects thereof to the energy change of the reflection condition and the penetration time of ultrasonic propagation waveforms. Surface waves are a mode of propagation of ultrasonic waves in a solid medium, i.e. they propagate only on the surface of an object whose thickness is much greater than the wavelength. The energy is mainly concentrated near the surface of the material to be transmitted, and the material has the characteristics of no dispersion, difficult attenuation and the like, and is particularly suitable for detecting the surface defects of the material. The traditional ultrasound is generated by excitation of a piezoelectric sensor, the sensor is required to be in contact with a measured object, a coupling agent needs to be added, the limitation of a detection environment is often caused, and an inspected object is polluted. Laser ultrasound has developed into an important branch of ultrasound in recent years, when laser irradiates the surface of a material, ultrasonic waves in various modes can be effectively generated, and the ultrasonic wave ultrasonic. Compared with the traditional ultrasonic nondestructive testing technology, the technology overcomes the defects of time and labor consumption, damage, large volume and the like of the traditional measuring method, so that the technology can be applied to real-time detection and monitoring of workpiece quality, nondestructive testing of materials, measurement in high-temperature and high-pressure environments and the like. The laser ultrasonic detection method with the advantages of non-contact, high frequency, high spatial resolution and the like has great advantages because the material near-surface buried defect can not be detected by adopting an optical means and is insensitive to the detection of the traditional body wave.
Most of the existing laser ultrasonic detection methods are complicated, the related devices are complicated, the difficulty in operation is high, the detection efficiency is low, and the detection precision is difficult to guarantee.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide the method for detecting the metal subsurface defect by using the laser ultrasonic, which is easy to operate, high in detection efficiency and high in detection precision. The technical scheme is as follows:
a method for ultrasonically detecting defects on a metal subsurface using laser light, comprising the steps of:
s10, acting the laser on the workpiece to be measured through a galvanometer scanning system;
s20, calculating the wave velocity of the laser-excited ultrasonic surface wave on the surface of the workpiece to be measured;
s30, calculating the arrival time of the incident signal of the ultrasonic surface wave and the arrival time of the reflected signal after the ultrasonic surface wave passes through the defect;
and S40, calculating the horizontal position of the defect and the perimeter of the boundary of the cross section of the defect according to the wave velocity of the ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of the incident signal and the arrival time of the reflected signal after the defect.
As a further improvement of the present invention, the step S20 specifically includes:
the method comprises the steps of setting two position reference points, collecting the horizontal position difference delta L and the arrival time difference delta T of a head wave signal of the two position reference points to obtain the wave velocity v of the laser-excited ultrasonic surface waveR(ii) a Wherein v isR＝ΔL/ΔT。
As a further improvement of the present invention, the step S40 specifically includes:
calculating the horizontal position d of the defect and the perimeter p of the boundary of the section of the defect according to the following formula;
p＝(tr2-tr1)·vR
wherein v isRSpeed of ultrasonic surface wave, t, for laser excitationiTime of arrival of incident ultrasonic surface wave signal at piezoelectric transducer, tr1And tr2Are respectively the first reflected wave signal R1And a second reflected wave signal R2Time of arrival at the piezoelectric sensor, d0Is a piezoelectric sensorThe distance of the front end of the device from its actual point of reception.
The invention aims to provide a system for detecting the metal subsurface defect by using laser ultrasonic, which has the advantages of simple structure, easy operation and high measurement precision, and adopts the following technical scheme:
a system for ultrasonically detecting metal subsurface defects using laser light, comprising:
a fiber laser for generating laser light;
the galvanometer scanning system is used for acting laser on a workpiece to be detected;
the piezoelectric sensor is arranged above the workpiece to be measured;
and the computer is connected with the piezoelectric sensor and comprises a data receiving module and a data processing module, the data receiving module is used for receiving signals acquired by the piezoelectric sensor, the data processing module is used for calculating the wave speed of the laser-excited ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of an incident signal of the ultrasonic surface wave and the arrival time of a reflected signal after the ultrasonic surface wave passes through the defect according to the signals, and calculating the horizontal position of the defect and the perimeter of the boundary of the section of the defect.
As a further improvement of the invention, the signals collected by the piezoelectric sensor comprise two position reference point horizontal position difference, head wave signal arrival time difference, incident signals and reflected signals after passing through defects.
As a further improvement of the invention, the data processing module obtains the wave speed v of the laser-excited ultrasonic surface wave according to the following formulaR；
vR＝ΔL/ΔT
Wherein, Δ L is the horizontal phase difference of two position reference points, and Δ T is the arrival time difference of the head wave signal.
As a further improvement of the present invention, the data processing module calculates the horizontal position d of the defect and the perimeter p of the defect cross-section boundary according to the following formula;
p＝(tr2-tr1)·vp
wherein v isRSpeed of ultrasonic surface wave, t, for laser excitationiTime of arrival of incident ultrasonic surface wave signal at piezoelectric transducer, tr1And tr2Are respectively the first reflected wave signal R1And a second reflected wave signal R2Time of arrival at the piezoelectric sensor, d0Is the distance of the front end of the piezoelectric sensor from its actual receiving point.
As a further improvement of the invention, the optical fiber laser further comprises a signal amplifier, an A/D high-speed data converter, an FIFO high-speed data stream buffer and a laser controller, the computer further comprises a control module, the control module controls the optical fiber laser through the laser controller, and the control module is also used for controlling the A/D high-speed data converter and the FIFO high-speed data stream buffer to acquire and store data.
As a further improvement of the present invention, a photoacoustic data synchronization control circuit for triggering the a/D high-speed data converter and the FIFO high-speed data stream buffer simultaneously with the laser triggering is further included.
As a further improvement of the invention, the device also comprises a three-dimensional adjustable sample table which is used for bearing and adjusting the workpiece to be measured.
The invention has the beneficial effects that:
the method and the system for detecting the metal subsurface defect by using the laser ultrasonic can detect the position and the size of the defect on the metal pressing surface, and have the advantages of simple operation, high detection efficiency and high detection precision.
The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following preferred embodiments are described in detail with reference to the accompanying drawings.
Drawings
FIG. 1 is a flow chart of a method for ultrasonic detection of metal subsurface defects using laser light in an embodiment of the present invention;
FIG. 2 is a schematic diagram of a system for ultrasonic detection of metal subsurface defects using laser light in an embodiment of the present invention;
FIG. 3 shows a first group d of embodiments of the present invention1And d2Down collecting ultrasonic surface wave signals;
FIG. 4 shows a second group d of an embodiment of the present invention1And d2And (c) down-sampling the ultrasonic surface wave signal.
Detailed Description
The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.
As shown in fig. 1, the method for detecting metal subsurface defects by using laser ultrasound in the embodiment of the present invention includes the following steps:
s10, acting the laser on the workpiece to be measured through a galvanometer scanning system;
s20, calculating the wave velocity of the laser-excited ultrasonic surface wave on the surface of the workpiece to be measured; the method specifically comprises the following steps:
the method comprises the steps of setting two position reference points, collecting the horizontal position difference delta L and the arrival time difference delta T of a head wave signal of the two position reference points to obtain the wave velocity v of the laser-excited ultrasonic surface waveR(ii) a Wherein v isR＝ΔL/ΔT。
S30, calculating the arrival time of the incident signal of the ultrasonic surface wave and the arrival time of the reflected signal after the ultrasonic surface wave passes through the defect;
and S40, calculating the horizontal position of the defect and the perimeter of the boundary of the cross section of the defect according to the wave velocity of the ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of the incident signal and the arrival time of the reflected signal after the defect. The method specifically comprises the following steps:
calculating the horizontal position d of the defect and the perimeter p of the boundary of the section of the defect according to the following formula;
p＝(tr2-tr1)·vp
wherein v isRSpeed of ultrasonic surface wave, t, for laser excitationiTime of arrival of incident ultrasonic surface wave signal at piezoelectric transducer, tr1And tr2Are respectively the first reflected wave signal R1And a second reflected wave signal R2Time of arrival at the piezoelectric sensor, d0Is the distance of the front end of the piezoelectric sensor from its actual receiving point.
Wherein the ultrasonic surface wave signals are acquired by a piezoelectric sensor. The data receiving module of the computer receives the signals, and the data processing module performs calculation processing on the signals.
Referring to fig. 2, a system for detecting metal subsurface defects by laser ultrasound in an embodiment of the present invention includes:
a fiber laser for generating laser light;
the galvanometer scanning system is used for acting laser on a workpiece to be detected;
the piezoelectric sensor is arranged above the workpiece to be measured;
and the computer is connected with the piezoelectric sensor and comprises a data receiving module and a data processing module, the data receiving module is used for receiving signals acquired by the piezoelectric sensor, the data processing module is used for calculating the wave speed of the laser-excited ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of an incident signal of the ultrasonic surface wave and the arrival time of a reflected signal after the ultrasonic surface wave passes through the defect according to the signals, and calculating the horizontal position of the defect and the perimeter of the boundary of the section of the defect.
The signals collected by the piezoelectric sensor comprise two position reference point horizontal position differences, head wave signal arrival time differences, incident signals and reflected signals after passing through defects.
The data processing module obtains the wave velocity v of the laser-excited ultrasonic surface wave according to the following formulaR；
vR＝ΔL/ΔT
Wherein, Δ L is the horizontal phase difference of two position reference points, and Δ T is the arrival time difference of the head wave signal.
The data processing module calculates the horizontal position d of the defect and the perimeter p of the boundary of the section of the defect according to the following formula;
p＝(tr2-tr1)·vR
wherein v isRSpeed of ultrasonic surface wave, t, for laser excitationiTime of arrival of incident ultrasonic surface wave signal at piezoelectric transducer, tr1And tr2Are respectively the first reflected wave signal R1And a second reflected wave signal R2Time of arrival at the piezoelectric sensor, d0Is the distance of the front end of the piezoelectric sensor from its actual receiving point.
In this embodiment, the system further includes a signal amplifier, an a/D high-speed data converter, an FIFO high-speed data stream buffer, a laser controller, and the computer further includes a control module, the control module controls the fiber laser through the laser controller, and the control module is further configured to control the a/D high-speed data converter and the FIFO high-speed data stream buffer to perform data acquisition and storage.
The signal amplifier can sensitively capture the sound wave with reduced energy caused by wave transmission attenuation and defect size effect, and overcomes the defect that the accuracy of the test system is influenced by errors in data processing caused by small received fluctuation signals.
In this embodiment, the system further comprises a photoacoustic data synchronization control circuit for triggering the a/D high speed data converter and the FIFO high speed data stream buffer at the same time as the laser triggering. The method can be used for collecting and processing large-scale data streams, reduces data loss and improves data post-processing efficiency.
In this embodiment, the system further includes a three-dimensional adjustable sample stage for carrying and adjusting the workpiece to be measured. The distance between the galvanometer scanning head and the workpiece to be measured is adjusted, the workpiece to be measured is positioned at the focal plane of the galvanometer scanning head, the effective area scanned by the galvanometer scanning head is positioned on the surface of the workpiece to be measured, and the laser scanning surface of the workpiece to be measured is parallel to the plane of the galvanometer scanning head.
In the experiment, a processed aluminum cuboid sample (the sample size: 150mm 20mm 30mm, the embedded defect size: 10mm 20mm) containing defects is placed on a three-dimensional adjustable sample table, the distance between a galvanometer scanning head and a workpiece to be detected enables the workpiece to be detected to be located at the focal plane of the galvanometer scanning head, an effective area capable of being scanned by the galvanometer scanning head is located at the center of an object to be detected, and the laser scanning surface of the object to be detected is parallel to the plane of the galvanometer scanning head.
Wherein the front end of the piezoelectric sensor is at a distance d from the actual receiving point012.5mm, and adjusting the horizontal distance d between the laser scanning center and the defect1And the horizontal distance d between the laser scanning center and the piezoelectric sensor2The test experiment is carried out, the obtained ultrasonic surface wave signals are shown in fig. 3 and 4, the arrival time of the incident wave signal, the first reflected wave signal and the second reflected wave signal corresponding to the two groups of experiments is calculated, and t is calculated respectivelyi+tr1And tr2-tr1The surface wave velocity v in the aluminum sample was measuredR2953.9m/s, the parameters d and p to be estimated corresponding to the defect can be calculated according to the formula, and the details are shown in table 1. As can be seen from Table 1, d measured by this method is very close to the actual value d1+d2And the perimeter p of the defect is close to the true value of 60mm, which proves the high efficiency and feasibility of the method in the invention.
TABLE 1
The above embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.
Claims (10)
1. A method for detecting metal subsurface defects by using laser ultrasound is characterized by comprising the following steps:
s10, acting the laser on the workpiece to be measured through a galvanometer scanning system;
s20, calculating the wave velocity of the laser-excited ultrasonic surface wave on the surface of the workpiece to be measured;
s30, calculating the arrival time of the incident signal of the ultrasonic surface wave and the arrival time of the reflected signal after the ultrasonic surface wave passes through the defect;
and S40, calculating the horizontal position of the defect and the perimeter of the boundary of the cross section of the defect according to the wave velocity of the ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of the incident signal and the arrival time of the reflected signal after the defect.
2. The method for ultrasonically detecting metal subsurface defects by using laser according to claim 1, wherein the step S20 specifically comprises:
the method comprises the steps of setting two position reference points, collecting the horizontal position difference delta L and the arrival time difference delta T of a head wave signal of the two position reference points to obtain the wave velocity v of the laser-excited ultrasonic surface waveR(ii) a Wherein v isR＝ΔL/ΔT。
3. The method for ultrasonically detecting metal subsurface defects by using laser according to claim 1, wherein the step S40 specifically comprises:
calculating the horizontal position d of the defect and the perimeter p of the boundary of the section of the defect according to the following formula;
p＝(tr2-tr1)·vR
wherein v isRSpeed of ultrasonic surface wave, t, for laser excitationiTime of arrival of incident ultrasonic surface wave signal at piezoelectric transducer, tr1And tr2Are respectively the first reflected wave signal R1And a second reflected wave signal R2Time of arrival at the piezoelectric sensor, d0Is the distance of the front end of the piezoelectric sensor from its actual receiving point.
4. A system for ultrasonically detecting defects in a metal subsurface using a laser, comprising:
a fiber laser for generating laser light;
the galvanometer scanning system is used for acting laser on a workpiece to be detected;
the piezoelectric sensor is arranged above the workpiece to be measured;
and the computer is connected with the piezoelectric sensor and comprises a data receiving module and a data processing module, the data receiving module is used for receiving signals acquired by the piezoelectric sensor, the data processing module is used for calculating the wave speed of the laser-excited ultrasonic surface wave on the surface of the workpiece to be detected, the arrival time of an incident signal of the ultrasonic surface wave and the arrival time of a reflected signal after the ultrasonic surface wave passes through the defect according to the signals, and calculating the horizontal position of the defect and the perimeter of the boundary of the section of the defect.
5. The system for detecting metal subsurface defects by using laser ultrasound as claimed in claim 4, wherein the signals collected by the piezoelectric sensor comprise two position reference point horizontal phase differences, a head wave signal arrival time difference, an incident signal and a reflected signal after passing through the defect.
6. The system for ultrasonic detection of metal subsurface defects with laser according to claim 5, wherein said data processing module obtains the laser-excited surface acoustic wave velocity v according to the following formulaR；
vR＝ΔL/ΔT
Wherein, Δ L is the horizontal phase difference of two position reference points, and Δ T is the arrival time difference of the head wave signal.
7. The system for ultrasonic detection of metal subsurface defects with laser according to claim 5, wherein said data processing module calculates the horizontal position d of the defect and the perimeter p of the defect cross-section boundary according to the following formula;
p＝(tr2-tr1)·vR
wherein v isRSpeed of ultrasonic surface wave, t, for laser excitationiTime of arrival of incident ultrasonic surface wave signal at piezoelectric transducer, tr1And tr2Are respectively the first reflected wave signal R1And a second reflected wave signal R2Time of arrival at the piezoelectric sensor, d0Is the distance of the front end of the piezoelectric sensor from its actual receiving point.
8. The system for ultrasonic detection of metal sub-surface defects by laser according to claim 4, further comprising a signal amplifier, an A/D high-speed data converter, a FIFO high-speed data stream buffer, a laser controller, wherein the computer further comprises a control module, the control module controls the fiber laser through the laser controller, and the control module is further used for controlling the A/D high-speed data converter and the FIFO high-speed data stream buffer to perform data acquisition and storage.
9. The system for ultrasonic inspection of metal sub-surface defects with laser light of claim 8, further comprising a photoacoustic data synchronization control circuit for triggering the a/D high speed data converter and FIFO high speed data stream buffer at the same time as laser light triggering.
10. The system for ultrasonic inspection of metal subsurface defects with laser according to claim 4, further comprising a three-dimensional adjustable sample stage for carrying and adjusting the workpiece to be inspected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010393709.8A CN111693611A (en) | 2020-05-11 | 2020-05-11 | Method and system for detecting metal subsurface defects by using laser ultrasonic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010393709.8A CN111693611A (en) | 2020-05-11 | 2020-05-11 | Method and system for detecting metal subsurface defects by using laser ultrasonic |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111693611A true CN111693611A (en) | 2020-09-22 |
Family
ID=72477533
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010393709.8A Pending CN111693611A (en) | 2020-05-11 | 2020-05-11 | Method and system for detecting metal subsurface defects by using laser ultrasonic |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111693611A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113075298A (en) * | 2021-03-29 | 2021-07-06 | 重庆交通大学 | Concrete microcrack detection method based on laser ultrasonic technology |
| CN115684024A (en) * | 2022-10-25 | 2023-02-03 | 北京翔博科技股份有限公司 | Laser ultrasound-based residual stress distribution detection method and system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007017297A (en) * | 2005-07-07 | 2007-01-25 | Toshiba Corp | Laser ultrasonic inspection device and system equipped with it |
| CN107688051A (en) * | 2017-08-15 | 2018-02-13 | 浙江大学 | A kind of measuring method of the subsurface defect width based on Laser thermo-elastic generated surface acoustic waves |
-
2020
- 2020-05-11 CN CN202010393709.8A patent/CN111693611A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007017297A (en) * | 2005-07-07 | 2007-01-25 | Toshiba Corp | Laser ultrasonic inspection device and system equipped with it |
| CN107688051A (en) * | 2017-08-15 | 2018-02-13 | 浙江大学 | A kind of measuring method of the subsurface defect width based on Laser thermo-elastic generated surface acoustic waves |
Non-Patent Citations (1)
| Title |
|---|
| 未知: "《国外无损检测》", 31 October 1981, 上海科学技术文献出版社, pages: 30 - 32 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113075298A (en) * | 2021-03-29 | 2021-07-06 | 重庆交通大学 | Concrete microcrack detection method based on laser ultrasonic technology |
| CN113075298B (en) * | 2021-03-29 | 2024-03-29 | 重庆交通大学 | Concrete microcrack detection method based on laser ultrasonic technology |
| CN115684024A (en) * | 2022-10-25 | 2023-02-03 | 北京翔博科技股份有限公司 | Laser ultrasound-based residual stress distribution detection method and system |
| CN115684024B (en) * | 2022-10-25 | 2023-08-08 | 北京翔博科技股份有限公司 | Residual stress distribution detection method and system based on laser ultrasound |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107747922B (en) | Method for measuring subsurface defect buried depth based on laser ultrasound | |
| CN107688051B (en) | A kind of measurement method of the subsurface defect width based on Laser thermo-elastic generated surface acoustic waves | |
| CN103543206B (en) | A kind of aluminum alloy pretensioning plate unrelieved stress immersed ultrasonic test method | |
| CN103292753B (en) | Adopt the method for ultrasound wave water immersion focusing commercial measurement thermal barrier coating thickness | |
| CN101281172A (en) | Laser sonic surface wave stress test system | |
| CN102798667B (en) | Metal defect detection method of laser-electromagnetic ultrasonic nondestructive testing system | |
| CN111751448B (en) | Surface leakage wave ultrasonic synthetic aperture focusing imaging method | |
| CN103017953A (en) | Device for detecting residual stress close to surfaces of metal materials | |
| CN104865317A (en) | Transmission type air coupling ultrasonic scanning imaging method | |
| CN103543212B (en) | A kind of preparation method of the test block for the detection of aluminum alloy pretensioning plate unrelieved stress | |
| CN111693611A (en) | Method and system for detecting metal subsurface defects by using laser ultrasonic | |
| CN111174894B (en) | Laser ultrasonic transverse wave sound velocity measurement method | |
| CN111380955A (en) | Method for detecting defects of additive manufacturing part based on ultrasonic phased array | |
| CN104849351A (en) | Surface acoustic impedance detection method and system based on non-contact air coupling | |
| CN113533504A (en) | Sub-surface crack quantitative measurement method based on laser ultrasonic surface wave frequency domain parameters | |
| Liang et al. | Analysis of amplitude and frequency detection error of surface acoustic wave generated by laser line source | |
| CN111665296A (en) | Method and device for measuring three-dimensional radiation sound field of ultrasonic transducer based on EMAT | |
| CN104569155A (en) | Electromagnetic ultrasonic detection method for surface defects | |
| CN113777047A (en) | Method for identifying position and size of metal surface crack based on thermoelastic effect | |
| CN114280157A (en) | Sub-surface crack length quantitative detection method based on laser excitation surface wave | |
| JP2007107978A (en) | Ultrasonic measuring method of hot working material and ultrasonic measuring instrument of hot working material | |
| JP2002040001A (en) | Flaw detection method and device | |
| Imano | Detection of drilled hole on subsurface of aluminum plate with rayleigh ultrasonic wave field by laser probing | |
| Chang et al. | Development of non-contact air coupled ultrasonic testing system for reinforced concrete structure | |
| Zhao et al. | Hybrid laser ultrasonic inspection based on optical fiber technique |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200922 |
|
| RJ01 | Rejection of invention patent application after publication |