CN114062483B - Flexible sensor and metal member defect detection method - Google Patents
Flexible sensor and metal member defect detection method Download PDFInfo
- Publication number
- CN114062483B CN114062483B CN202111409300.1A CN202111409300A CN114062483B CN 114062483 B CN114062483 B CN 114062483B CN 202111409300 A CN202111409300 A CN 202111409300A CN 114062483 B CN114062483 B CN 114062483B
- Authority
- CN
- China
- Prior art keywords
- sensing unit
- magnetic fluid
- substrate
- metal component
- 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.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/83—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields
- G01N27/85—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields using magnetographic methods
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/83—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields
- G01N27/84—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields by applying magnetic powder or magnetic ink
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The invention discloses a flexible sensor and a metal member defect detection method, wherein the flexible sensor comprises a flexible substrate and a sensing unit, the sensing units are arranged on the substrate in an array form, the sensing unit comprises a container and an exciting coil, the container is filled with magnetic fluid and transparent solution with the same density, and the transparent solution and the magnetic fluid are mutually incompatible and do not react chemically; the exciting coil is arranged at the outer end part of the container, which is close to the substrate, and is used for generating a magnetic field after exciting current is introduced. The invention can rapidly, nondestructively and accurately detect the defects of the metal component, the number of the sensing units is not limited by hardware equipment, the applicability is strong, the reliability is high, the labor cost and the economic cost are reduced, and the invention has important engineering application value.
Description
Technical Field
The invention belongs to the technical field of flexible sensors, and relates to a flexible sensor and a metal member defect detection method.
Background
The metal component is widely applied in the industrial fields of aerospace, petrochemical industry, nuclear power and the like, and due to various complex service environments, various defects are easily generated in the metal component, the integrity and the reliability of the metal component are affected, and the metal component is invalid when serious, so that serious safety production accidents are caused; therefore, the nondestructive detection technology is of great significance in efficiently detecting the defects of the metal component.
The ultrasonic detection technology can accurately position defects, is portable and harmless to human bodies, but generally requires smooth surfaces of detected objects and a large amount of couplant, and requires operators to have higher technical level, and the ray detection technology is easy to detect the defects of the internal bodies of the detected objects, but has lower detection precision, higher cost and risks of environmental pollution and injury to operators; the penetration detection result is visual and reliable, the detection sensitivity is high, but the surface defect is detected as much as possible; the eddy current detection has higher sensitivity to the detection of the member defects of the metal material, but the number of sensor units in the array probe is limited by the hardware equipment, so that the rapid detection is difficult to realize, the detection efficiency is low, and the influence of environmental noise is easy to realize.
Disclosure of Invention
In order to solve the problems, the invention provides the flexible sensor which can rapidly, nondestructively and accurately detect the defects of the metal component, the number of the sensing units is not limited by hardware equipment, the applicability is strong, the reliability is high, the labor cost and the economic cost are reduced, and the flexible sensor has important engineering application value.
Another object of the present invention is to provide a method for detecting defects of a metal member, using the above flexible sensor.
The invention adopts the technical proposal that the flexible sensor comprises
A substrate, the substrate being flexible; and
a plurality of sensing units mounted on a substrate in an array form;
the sensing unit comprises
The container is filled with magnetic fluid and transparent solution with the same density, and the transparent solution and the magnetic fluid are mutually incompatible and do not have chemical reaction; and
and the exciting coil is arranged at the outer end part of the container, close to the substrate, and is used for generating a magnetic field after exciting current is introduced.
Further, the exciting coil is sequentially connected with a power amplifier and a signal generator and is used for inputting square wave exciting current signals to the exciting coil.
Further, the container is cylindrical in shape.
Further, the exciting coil is disc-shaped, and the exciting coil is coaxial with the container.
Further, the distance between the sensing units is the diameter of the sensing units.
Further, the inner wall of the container is coated with a uniform, transparent oleophobic coating.
Further, the substrate adopts a flexible PCB.
The metal member defect detection method adopts the flexible sensor and specifically comprises the following steps:
step 1, establishing a metal member defect depth calibration curve;
the substrate of the flexible sensor is tightly attached to a metal component to be tested, a square wave excitation current signal is adopted to drive an excitation coil to work, three-dimensional morphology of magnetic fluid in each sensing unit is obtained after a period of time, and the average value of the magnetic fluid volume difference in the sensing unit corresponding to the sensing unit under the working condition of a standard metal component under the different excitation currents is taken as a signal characteristic; substituting the signal characteristics into the calibration curve to obtain the corresponding defect depth of each sensing unith 1 、h 2 、h 3… h n 。
Further, the step 1 specifically includes:
the exciting coils of the signal generator, the power amplifier and the flexible sensor are connected in sequence, and the substrate is tightly attached to the flexible sensor with the thickness ofdThe standard metal component of (2) adopts square wave excitation current signal to drive the excitation coil to work so as to obtain excitation current I 1 Three-dimensional morphology of magnetic fluid in each sensing unitP 1,1,1 、P 1,2,1 、P 1,3,1… P 1,n,1 The excitation current I can be obtained in the same way 2 Three-dimensional morphology of magnetic fluid in each sensing unitP 2,1,1 、P 2,2,1 、P 2,3,1… P 2,n,1 ；
The substrate of the flexible sensor is tightly adhered to the substrate with the thickness of 0.9dThe same square wave exciting current signal is adopted to drive the exciting coil to work, and after a period of time, exciting current I is respectively obtained 1 And I 2 Three-dimensional morphology of magnetic fluid in each sensing unitP 1,1,2 、P 1,2,2 、P 1,3,2… P 1,n,2 AndP 2,1,1 、P 2,2,1 、P 2,3,1… P 2,n,1 toV 1,1 、V 1,2 、V 1,3… V 1,n As a signal feature, whereV 1,1 =（|P 1,1,2 - P 1,1,1 |+|P 2,1,1 - P 2,1,1 |）/2；
V 1,1 、V 1,2 、V 1,3… V 1,n Indicating a metal member thickness of 0.9dSignal characteristics corresponding to each sensing unit; the same applies to the thickness of 0.8d、0.7d、0.6d、0.5d、0.4d、0.3d、0.2dAnd 0.1dThe signal characteristics corresponding to the sensing units are respectively as followsV 2,1 、V 2,2 、V 2,3… V 2,n ，V 3,1 、V 3,2 、V 3,3… V 3,n ，V 4,1 、V 4,2 、V 4,3… V 4,n ，V 5,1 、V 5,2 、V 5,3… V 5,n ，V 6,1 、V 6,2 、V 6,3… V 6,n ，V 7,1 、V 7,2 、V 7,3… V 7,n ，V 8,1 、V 8,2 、V 8,3… V 8,n AndV 9,1 、V 9,2 、V 9,3… V 9,n ；
characterised by the signal respectivelyV 1,1 、V 2,1 、V 3,1… V 9,1 ，V 1,2 、V 2,2 、V 3,2… V 9,2 ，V 1,3 、V 2,3 、V 3,3… V 9,3 …V 1,n 、V 2,n 、V 3,n… V 9,n On the abscissa of 0.1d、0.2d、0.3d、0.4d、0.5d、0.6d、0.7d、0.8dAnd 0.9dOn the ordinate, the defect depth of the metal component can be obtainedd x Correlation curves with signal characteristics of each sensorDepth of the trapd x Standard metal member thickness-metal member thickness to be measured; performing secondary fitting on each association curve to obtain a fitting formula corresponding to each sensing unitd x，1 =a 1 V 2 +b 1 V+c 1 ，d x，2 =a 2 V 2 +b 2 V+c 2 ，d x，3 =a 3 V 2 +b 3 V+c 3 ，…d x n， =a n V 2 +b n V+c n Whereina 1 、a 2 、a 3 …a n ，b 1 、b 2 、b 3 …b n ，c 1 、c 2 、c 3 …c n The quadratic term coefficient, the first term coefficient and the constant term are respectively carried out;d x n， representing the fitting formula corresponding to the nth sensing unit,Vrepresenting the signal characteristics.
Further, the step 2 specifically includes:
the substrate of the flexible sensor is tightly attached to a metal component to be tested, a square wave excitation current signal is adopted to drive an excitation coil to work, and after a period of time, an excitation current I is obtained 1 And I 2 Three-dimensional morphology of magnetic fluid in each sensing unitY 1,1,2 、Y 1,2,2 、Y 1,3,2… Y 1,n,2 AndY 2,1,1 、Y 2,2,1 、Y 2,3,1… Y 2,n,1 with the magnetic fluid in the sensing unit exciting current I 1 And I 2 When the average value of the magnetic fluid volume difference in the corresponding sensing unit under the working condition of the standard metal componentv 1,1 、v 1,2 、v 1,3… v 1,n As a signal feature; characterizing a signalv 1,1 、v 1,2 、v 1,3… v 1,n Substituting into fitting formulad x，1 =a 1 V 2 +b 1 V+c 1 ，d x，2 =a 2 V 2 +b 2 V+c 2 ，d x，3 =a 3 V 2 +b 3 V+c 3 ，…d x n， =a n V 2 +b n V+c n Obtaining the corresponding defect depth at each sensing unith 1 、h 2 、h 3… h n 。
The beneficial effects of the invention are as follows:
1. the invention converts the defect information into the magnetic fluid shape information by organically combining the exciting coil and the magnetic fluid, breaks through the hardware restriction of the traditional detection method, has higher electromagnetic noise frequency, no fixed direction, weaker deformation influence on the magnetic fluid and lower influence on detection signals, thereby ensuring that the flexible sensor has stronger capability of resisting the interference of the environment electromagnetic noise and higher accuracy. Meanwhile, the number of the sensing units is not limited by hardware equipment, the rapid detection of a large-area to-be-detected area can be realized in one-time detection, the detection efficiency is higher, and the method is applicable to metal components with different surface shapes.
2. The density of the magnetic fluid adopted by the invention is the same as that of the transparent solution, so that the magnetic fluid deforms more obviously under the action of exciting current, and the sensitivity of a detection signal can be effectively improved. The adopted exciting current can ensure that the magnetic fluid can be always positioned at one side of the exciting coil in the sensing unit, so that the detection result is not influenced by the spatial position of the flexible sensor, and the reliability is high.
3. The method can accurately position the defects, obtain the two-dimensional contour information and the depth information of the defects, has simple structure and low cost, realizes rapid and efficient detection, and has higher industrial application value.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic structural diagram of a flexible sensor according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of the excitation current signal according to an embodiment of the present invention.
1. The sensor comprises a substrate, a sensing unit, a container, a transparent solution, magnetic fluid and an exciting coil.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, based on the embodiments of the present invention, which a person of ordinary skill in the art would obtain without inventive faculty, are within the scope of the present invention for protecting the sensing unit.
In the case of example 1,
a flexible sensor, as shown in fig. 1, comprises a flexible substrate 1, a sensing unit 2; a plurality of the sensing units 2 are arranged on the substrate 1 in an array form, and the sensing units 2 comprise a container 3 and an exciting coil 6; the container 3 is filled with the magnetic fluid 5 and the transparent solution 4 with the same density, and the transparent solution 4 and the magnetic fluid 5 are mutually incompatible and do not have chemical reaction; an exciting coil 6 is mounted on the outer end of the container 3 near the substrate 1 for generating a magnetic field upon application of an exciting current.
The container 3 is cylindrical in shape, the exciting coil 6 is disc-shaped, the exciting coil 6 is coaxial with the container 3, and the inner wall of the container 3 is coated with a uniform and transparent oleophobic coating. The transparent solution 4 cannot be too small, so that the magnetic fluid 5 cannot contact the top of the container 3 after being deformed, and the detection precision is improved; in some embodiments, the volume ratio of the magnetic fluid 5 to the transparent solution 4 is between 4:1 and 1:1.
The density of the magnetic fluid 5 is the same as that of the transparent solution 4, so that the magnetic fluid 5 deforms more obviously under the action of a magnetic field generated by the exciting coil 6, and the sensitivity of a detection signal can be effectively improved.
The exciting coil 6 is sequentially connected with the power amplifier and the signal generator and is used for inputting square wave exciting current signals to the exciting coil 6, so that the magnetic fluid 5 can be ensured to be always positioned at one side of the exciting coil 6 in the sensing unit 2, and therefore, the detection result is not influenced by the spatial position of the flexible sensor. The magnetic force generated after the excitation coil 6 works can enable the excitation coil 6 to be clung to the metal component to be detected, and the detection precision is improved.
The transparent solution 4 has stable and transparent chemical property and does not react with the magnetic fluid 5 and the container 3; the magnetic fluid 5 is easy to deform under the action of a magnetic field, and a common black magnetic fluid is adopted in the embodiment.
The distance between the sensing units 2 is the diameter of the sensing units 2, so that the sensing units 2 can not interfere with each other, and the detection efficiency can be effectively guaranteed.
The substrate 1 is made of flexible materials and is not ductile; in an embodiment a flexible PCB is used.
In the case of example 2,
the metal member defect detection method specifically comprises the following steps:
step 1, establishing a metal member defect depth calibration curve;
the signal generator, the power amplifier and the flexible sensor of example 1 were connected in this order, and the flexible sensor was closely attached to a thickness ofdIs used for standard metal components with the period ofTDuty cycle 50%, peak value 50%ABias current ofAThe square wave excitation current signal of/2 drives the excitation coil 6 into operation, as shown in fig. 2. At 10TThen, the excitation current of 0.4 is obtained by a 3D laser scannerTThree-dimensional morphology of the magnetic fluid 5 in each sensing unit 2P 1,1,1 、P 1,2,1 、P 1,3,1… P 1,n,1 The excitation current is 0.6TThree-dimensional morphology of the magnetic fluid 5 in each sensing unit 2P 2,1,1 、P 2,2,1 、P 2,3,1… P 2,n,1 . The flexible sensor is tightly attached to the thickness of 0.9dThe exciting coil 6 is driven to operate by the square wave exciting current signal, and the metal component is shown as 10TThen, respectively obtaining excitation current of 0.4 by a 3D laser scannerTAnd 0.6TThree-dimensional morphology of magnetic fluid in each sensing unitP 1,1,2 、P 1,2,2 、P 1,3,2… P 1,n,2 AndP 2,1,1 、P 2,2,1 、P 2,3,1… P 2,n,1 with the excitation current of the magnetic fluid 5 in the sensing unit 2 being 0.4TAnd 0.6TAverage value of volume difference of magnetic fluid 5 in standard metal member sensing unit 2V 1,1 、V 1,2 、V 1,3… V 1,n As a signal feature. Select excitation current 0.4TAnd 0.6TThe averaging is to improve accuracy. The excitation current signals are all square waves, and the frequency spectrum information of the square waves is rich. The duty cycle is 50%, and the induction current is guaranteed to have sufficient rising time and falling time.
V 1,1 、V 1,2 、V 1,3… V 1,n Indicating a metal member thickness of 0.9dSignal characteristics corresponding to each sensing unit 2; the same can be obtained for thicknesses of 0.8 respectivelyd、0.7d、0.6d、0.5d、0.4d、0.3d、0.2dAnd 0.1dThe corresponding signal characteristics of each sensing unit 2 are respectively as followsV 2,1 、V 2,2 、V 2,3… V 2,n ，V 3,1 、V 3,2 、V 3,3… V 3,n ，V 4,1 、V 4,2 、V 4,3… V 4,n ，V 5,1 、V 5,2 、V 5,3… V 5,n ，V 6,1 、V 6,2 、V 6,3… V 6,n ，V 7,1 、V 7,2 、V 7,3… V 7,n ，V 8,1 、V 8,2 、V 8,3… V 8,n AndV 9,1 、V 9,2 、V 9,3… V 9,n 。
the basic principle of the defect detection in the embodiment of the invention is an electromagnetic induction principle, when defects exist, the defects can generate disturbance on vortex, the magnetic field can change, and the shape of the magnetic fluid can also change. Thickness of 0.9 respectivelyd、 0.8d、0.7d、0.6d、0.5d、0.4d、0.3d、0.2dAnd 0.1dThe metal member of (a) means that the overall thickness is 0.9d、 0.8d、0.7d、0.6d、0.5d、0.4d、0.3d、0.2dAnd 0.1dThe defect is the integral corrosion thinning defect, so that the calibration is convenient.
For each sensor unit 2, the signal characteristics are respectively adoptedV 1,1 、V 2,1 、V 3,1… V 9,1 ，V 1,2 、V 2,2 、V 3,2… V 9,2 ，V 1,3 、V 2,3 、V 3,3… V 9,3 …V 1,n 、V 2,n 、V 3,n… V 9,n On the abscissa of 0.1d、0.2d、0.3d、0.4d、0.5d、0.6d、0.7d、0.8dAnd 0.9dOn the ordinate, the defect depth of the metal component can be obtainedd x Performing secondary fitting on each correlation curve with the correlation curve of each sensor signal characteristic to obtain a fitting formula corresponding to each sensing unitd x，1 =a 1 V 2 +b 1 V+c 1 ，d x，2 =a 2 V 2 +b 2 V+c 2 ，d x，3 =a 3 V 2 +b 3 V+c 3 ，…d x n， =a n V 2 +b n V+c n Whereina 1 、a 2 、a 3 …a n ，b 1 、b 2 、b 3 …b n ，c 1 、c 2 、c 3 …c n The quadratic term coefficient, the first order term coefficient and the constant term, respectively.d x Indicating the depth of the defect,d x n， representing the fitting formula corresponding to the nth sensor,Vrepresenting the signal characteristics.
the signal generator, the power amplifier and the flexible sensor in the embodiment 1 are connected in sequence, and the flexible sensor is closely attached to the metal member to be tested, with the adoption of the period ofTDuty ratio of 50%, peak-to-peak value ofABias current ofAThe square wave excitation current signal of/2 drives the excitation coil 6 to operate. At 10TThen, respectively obtaining excitation current of 0.4 by a 3D laser scannerTAnd 0.6TWhen the magnetic fluid 5 in each sensing unit 2 has three-dimensional morphologyY 1,1,2 、Y 1,2,2 、Y 1,3,2… Y 1,n,2 AndY 2,1,1 、Y 2,2,1 、Y 2,3,1… Y 2,n,1 with the excitation current of the magnetic fluid 5 in the sensing unit 2 being 0.4TAnd 0.6TMean value of volume difference of magnetic fluid 5 in sensing unit 2 under working condition of standard metal componentv 1,1 、v 1,2 、v 1,3… v 1,n As a signal feature. Characterizing a signalv 1,1 、v 1,2 、v 1,3… v 1,n Substituting into fitting formulad x，1 =a 1 V 2 +b 1 V+c 1 ，d x，2 =a 2 V 2 +b 2 V+c 2 ，d x，3 =a 3 V 2 +b 3 V+c 3 ，…d x n， =a n V 2 +b n V+c n By, i.e. byv 1,1 Instead of fitting formulad x，1 =a 1 V 2 +b 1 V+c 1 A kind of electronic deviceVCorresponding to each sensing unit can be obtainedd x，1 、d x，2 、d x， 3…d x n， Depth of defecth 1 、h 2 、h 3… h n 。
In the ideal case of a device such as a mobile phone,P 1,1,2 、P 1,2,2 、P 1,3,2… P 1,n,2 the sensor units 2 are identical, but are actually different in operation, because of the production and processing technology and assembly problems, the size difference exists in each sensor unit 2, and the detection result is different, so that each sensor unit 2 needs to be calibrated respectively, the signal characteristics are different when the calibration is performed, and the fitting formulas are also different.
The traditional magnetic field sensor is interfered by electromagnetic noise, and can influence signals in related circuits and further influence measurement results. According to the embodiment of the invention, hardware such as a signal amplifier, a filter, a data acquisition board card and the like is not needed, so that the number of the sensing units 2 is less limited by hardware equipment, and the applicability is strong.
According to the embodiment of the invention, the magnetic field is generated by externally adding the exciting coil, and then the magnetic fluid is deformed under the action of the magnetic field, so that the magnetic fluid is actively deformed; compared with the prior art that induction voltage generated by induction in a coil is used as a signal, the magnetic fluid appearance is used as a signal for feature extraction, and the magnetic fluid detection method is high in detection efficiency, low in cost and high in reliability.
The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.
Claims (9)
1. A method for detecting defects of a metal member, characterized in that a flexible sensor is used comprising:
a substrate (1), the substrate (1) being flexible; and
a plurality of sensing units (2), wherein the sensing units (2) are arranged on the substrate (1) in an array form;
the sensor unit (2) comprises
A container (3), wherein the container (3) is filled with magnetic fluid (5) and transparent solution (4) with the same density, and the transparent solution (4) and the magnetic fluid (5) are mutually incompatible and do not have chemical reaction; and
the exciting coil (6) is arranged at the outer end part of the container (3) close to the substrate (1) and is used for generating a magnetic field after exciting current is introduced;
the method specifically comprises the following steps of:
step 1, establishing a metal member defect depth calibration curve;
step 2, detecting defects of the metal component;
the substrate (1) of the flexible sensor is tightly attached to a metal component to be tested, a square wave excitation current signal with bias current of A/2 is adopted to drive an excitation coil (6) to work, so that the magnetic fluid (5) can be always positioned at one side of the excitation coil (6) in the sensing unit (2), and the peak value of the square wave is A; after a period of time, three-dimensional morphology of the magnetic fluid (5) in each sensing unit (2) is obtained, and the average value of the volume difference of the magnetic fluid (5) in each sensing unit (2) corresponding to the sensing unit (2) under the working condition of the standard metal member at the time of different excitation currents is taken as a signal characteristic; substituting the signal characteristics into the calibration curve to obtain the corresponding defect depth h at each sensing unit (2) 1 、h 2 、h 3 …h n 。
2. The method for detecting the defects of the metal component according to claim 1, wherein the exciting coil (6) is sequentially connected with a power amplifier and a signal generator, and is used for inputting square wave exciting current signals to the exciting coil (6).
3. A method of detecting defects in a metal structure according to claim 1, wherein the container (3) is cylindrical in shape.
4. A method of detecting defects in a metal structure according to claim 3, wherein the exciting coil (6) is disc-shaped, and the exciting coil (6) is coaxial with the container (3).
5. A method of detecting defects in a metal member according to claim 1, wherein the spacing between the sensing units (2) is the diameter of the sensing units (2).
6. A method of detecting defects in a metal component according to claim 1, wherein the inner wall of the container (3) is coated with a uniform, transparent oleophobic coating.
7. A metal component defect detection method according to claim 1, characterized in that the substrate (1) is a flexible PCB.
8. The method for detecting defects of metal members according to claim 1, wherein said step 1 specifically comprises:
the exciting coil (6) of the signal generator, the power amplifier and the flexible sensor are connected in sequence, the substrate (1) is tightly attached to a standard metal component with the thickness of d, the exciting coil (6) is driven to work by adopting square wave exciting current signals, and exciting current I is obtained 1 When the three-dimensional morphology P of the magnetic fluid (5) in each sensing unit (2) is in a state of 1,1,1 、P 1,2,1 、P 1,3,1 …P 1,n,1 The excitation current I can be obtained in the same way 2 Three magnetic fluids (5) in each sensing unit (2)Dimension P 2,1,1 、P 2,2,1 、P 2,3,1 …P 2,n,1 ；
The substrate (1) of the flexible sensor is tightly attached to a metal component with the thickness of 0.9d, the same square wave excitation current signal is adopted to drive the excitation coil (6) to work, and after a period of time, excitation current I is respectively obtained 1 And I 2 When the three-dimensional morphology P of the magnetic fluid (5) in each sensing unit (2) is in a state of 1,1,2 、P 1,2,2 、P 1,3,2 …P 1,n,2 And P 2,1,1 、P 2,2,1 、P 2,3,1 …P 2,n,1 In V 1,1 、V 1,2 、V 1,3 …V 1,n As a signal feature, where V 1,1 ＝(|P 1,1,2 -P 1,1,1 |+|P 2,1,1 -P 2,1,1 |)/2；
V 1,1 、V 1,2 、V 1,3 …V 1,n Signal characteristics corresponding to each sensing unit (2) with the thickness of 0.9d of the metal component are represented; in the same way, for the metal components with the thicknesses of 0.8d, 0.7d, 0.6d, 0.5d, 0.4d, 0.3d, 0.2d and 0.1d respectively, the corresponding signal characteristics of each sensing unit (2) are V respectively 2,1 、V 2,2 、V 2,3 …V 2,n ，V 3,1 、V 3,2 、V 3,3 …V 3,n ，V 4,1 、V 4,2 、V 4,3 …V 4,n ，V 5,1 、V 5,2 、V 5,3 …V 5,n ，V 6,1 、V 6,2 、V 6,3 …V 6,n ，V 7,1 、V 7,2 、V 7,3 …V 7,n ，V 8,1 、V 8,2 、V 8,3 …V 8,n And V 9,1 、V 9,2 、V 9,3 …V 9,n ；
Respectively by signal characteristics V 1,1 、V 2,1 、V 3,1 …V 9,1 ，V 1,2 、V 2,2 、V 3,2 …V 9,2 ，V 1,3 、V 2,3 、V 3,3 …V 9,3 …V 1,n 、V 2,n 、V 3,n …V 9,n On the abscissa, 0.1d, 0.2d, 0.3d, 0.4d, 0.5d, 0.6d, 07d, 0.8d and 0.9d are vertical coordinates, and the defect depth d of the metal component can be obtained x Correlation curves with signal characteristics of each sensor, defect depth d x Standard metal member thickness-metal member thickness to be measured; performing secondary fitting on each association curve to obtain a fitting formula d corresponding to each sensing unit x，1 ＝a 1 V 2 +b 1 V+c 1 ，d x，2 ＝a 2 V 2 +b 2 V+c 2 ，d x，3 ＝a 3 V 2 +b 3 V+c 3 ，…d x，n ＝a n V 2 +b n V+c n Wherein a is 1 、a 2 、a 3 …a n ，b 1 、b 2 、b 3 …b n ，c 1 、c 2 、c 3 …c n The quadratic term coefficient, the first term coefficient and the constant term are respectively carried out; d, d x，n And (3) representing a fitting formula corresponding to the nth sensing unit (2), and V representing signal characteristics.
9. The method for detecting defects of metal members according to claim 1, wherein said step 2 comprises:
the substrate (1) of the flexible sensor is tightly attached to a metal component to be tested, a square wave excitation current signal is adopted to drive an excitation coil (6) to work, and after a period of time, an excitation current I is obtained 1 And I 2 When the magnetic fluid (5) in each sensing unit (2) has three-dimensional shape Y 1,1,2 、Y 1,2,2 、Y 1,3,2 …Y 1,n,2 And Y 2,1,1 、Y 2,2,1 、Y 2,3,1 …Y 2,n,1 With the excitation current I of the magnetic fluid (5) in the sensing unit (2) 1 And I 2 When the average value v of the volume difference of the magnetic fluid (5) in the sensing unit (2) corresponds to the standard metal component working condition 1,1 、v 1,2 、v 1,3 …v 1,n As a signal feature; signature v 1,1 、v 1,2 、v 1,3 …v 1,n Substituting into fitting formula d x，1 ＝a 1 V 2 +b 1 V+c 1 ，d x，2 ＝a 2 V 2 +b 2 V+c 2 ，d x，3 ＝a 3 V 2 +b 3 V+c 3 ，…d x，n ＝a n V 2 +b n V+c n Obtaining the corresponding defect depth h at each sensing unit 1 、h 2 、h 3 …h n 。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111409300.1A CN114062483B (en) | 2021-11-25 | 2021-11-25 | Flexible sensor and metal member defect detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111409300.1A CN114062483B (en) | 2021-11-25 | 2021-11-25 | Flexible sensor and metal member defect detection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114062483A CN114062483A (en) | 2022-02-18 |
| CN114062483B true CN114062483B (en) | 2023-05-23 |
Family
ID=80276057
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111409300.1A Active CN114062483B (en) | 2021-11-25 | 2021-11-25 | Flexible sensor and metal member defect detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114062483B (en) |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63239904A (en) * | 1987-03-27 | 1988-10-05 | Nippon Seiko Kk | Photoset magnetic fluid |
| CN1169532A (en) * | 1996-06-21 | 1998-01-07 | 上海大学 | Method for measuring fluid Hall potential |
| CN101493184B (en) * | 2009-02-24 | 2013-11-20 | 华南理工大学 | Clearance structure magnetic fluid flow control device |
| TW201140137A (en) * | 2009-11-06 | 2011-11-16 | Ibm | Deformable ferrofluid layer devices for optical modulation and micromolding |
| CN102879478A (en) * | 2011-10-24 | 2013-01-16 | 南通天华和睿科技创业有限公司 | Electromagnetic ultrasonic detection probe |
| CN104748666A (en) * | 2013-12-30 | 2015-07-01 | 中核武汉核电运行技术股份有限公司 | Deep defect quantifying method based on eddy rotating probe signal |
| KR101977921B1 (en) * | 2017-08-14 | 2019-05-13 | 조선대학교산학협력단 | A nondestructive testing apparatus including spiral direction current induction means |
| CN109737899A (en) * | 2019-01-25 | 2019-05-10 | 北京科技大学 | A kind of metal material crack-type defect depth measurement device and method |
| CN110232853A (en) * | 2019-06-05 | 2019-09-13 | 杭州魔象智能科技有限公司 | A kind of magnetic fluid drop deformation and segregation phenomenon observation experiment system and test method |
| CN113049675B (en) * | 2021-04-09 | 2022-07-29 | 中国石油大学(华东) | Rotating electromagnetic field pipeline defect layered detection probe and method |
-
2021
- 2021-11-25 CN CN202111409300.1A patent/CN114062483B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114062483A (en) | 2022-02-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1841060B (en) | Inspection method and system using multifrequency phase analysis | |
| CN206489114U (en) | The sensor and system of type multimode electromagnetic ultrasound and Magnetic Flux Leakage Inspecting | |
| CN105606268B (en) | Welding residual stress ultrasonic evaluation method based on the measurement of dynamic magnetostriction coefficient | |
| Ma et al. | Excitation and detection of shear horizontal waves with electromagnetic acoustic transducers for nondestructive testing of plates | |
| CN103257181A (en) | Metal sheet defect detection device and method in high-speed motion state | |
| Wu et al. | Nondestructive testing for corrosion evaluation of metal under coating | |
| CN102661995A (en) | Electromagnetic acoustic and magnetic leakage compounded detection method | |
| Uchimoto et al. | Evaluation of fatigue cracks by an angle beam EMAT–ET dual probe | |
| Guo et al. | Physic perspective fusion of electromagnetic acoustic transducer and pulsed eddy current testing in non-destructive testing system | |
| CN109668506A (en) | A kind of magnetic metal material thickness detecting method based on vortex steady-state characteristic | |
| Ulapane et al. | Designing a pulsed eddy current sensing set-up for cast iron thickness assessment | |
| Urayama et al. | Application of EMAT/EC dual probe to monitoring of wall thinning in high temperature environment | |
| CN105651439B (en) | Based on the polarized electromagnetic acoustic residual stress and strain detection method of Rayleigh wave polarization | |
| CN114062483B (en) | Flexible sensor and metal member defect detection method | |
| Okolo et al. | Axial magnetic field sensing for pulsed magnetic flux leakage hairline crack detection and quantification | |
| Bernieri et al. | Characterization of an eddy-current-based system for nondestructive testing | |
| Marchand et al. | Innovative flexible eddy current probes for the inspection of complex parts | |
| US8624589B2 (en) | Magnetostrictive probes for surface wave testing of thick walled structures | |
| CN101806590B (en) | Method for using higher standing wave resonance for quantitatively detecting thickness of elastic plates | |
| Chen et al. | Oil-tank weld detection using EMAT | |
| Wang et al. | A new system for defects inspection of boiler water wall tubes using a combination of EMAT and MFL | |
| Angani et al. | Dual core differential pulsed eddy current probe to detect the wall thickness variation in an insulated stainless steel pipe | |
| Cobb et al. | Nuclear containment inspection using an array of guided wave sensors for damage localization | |
| UCHIMOTO et al. | Field application of electromagnetic acoustic resonance to inspection of pipe wall thinning in a nuclear power plant | |
| Sophian | Characterisation of surface and sub-surface discontinuities in metals using pulsed eddy current sensors |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |