Defect distinguishing method and device based on eddy current detection

Abstract

The invention discloses a defect distinguishing method and device based on eddy current testing, and belongs to the technical field of electromagnetic nondestructive detection.The method comprises the steps that a stress voltage calibration curve of a calibration test piece is obtained, and a standard defect voltage relation is determined; acquiring voltage position test data of the to-be-tested piece, and comparing the voltage position test data with the stress voltage calibration curve to obtain a voltage position curve of the to-be-tested piece; comparing the voltage position curve with a standard defect voltage relationship, and determining the defect type of the to-be-tested piece; a judgment basis is set by obtaining a stress voltage calibration curve of a calibration test piece and determining a standard defect voltage relationship; comparing the voltage position test data of the to-be-tested piece with the stress voltage calibration curve to obtain a voltage position curve of the to-be-tested piece; by comparing the voltage position curve with the standard defect voltage relation, the defect type of the to-be-tested piece is determined, and the defect type is directly determined according to the eddy current testing data.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic nondestructive testing, and in particular to a defect differentiation method and device based on eddy current testing. Background Art

[0002] During the service life, stress concentration and macro defects in load-bearing steel structures will lead to the risk of structural failure, affect the quality of industrial production, and endanger the development of the national economy and the safety of people's property. Non-destructive testing and evaluation of stress and defects in ferromagnetic materials and components is a key measure to ensure the integrity of their structure, predict service life, and reduce maintenance costs.

[0003] At present, the eddy current detection method is generally used to obtain the secondary magnetic field excited by the exciting magnetic field of the material, and analyze the signal changes of the detection coil or magnetic sensitive element to determine the macro defects and stress state of the material. However, the existing eddy current detection technology often only focuses on the detection of defects or stresses. There is no method that can effectively distinguish between macro defects and stress concentration areas, and there is also a lack of technical means to characterize the defects contained in the stress concentration area. In other words, the existing technology cannot detect the defect type of the load-bearing steel structure in a timely manner.

[0004] Therefore, in the process of electromagnetic nondestructive testing of steel structures in the prior art, there is a problem that it is difficult to determine the defect type in a timely manner. Summary of the invention

[0005] In view of this, it is necessary to provide a defect differentiation method and device based on eddy current detection to solve the problem in the prior art that it is difficult to timely determine the defect type during the electromagnetic non-destructive testing of steel structures.

[0006] In order to solve the above problems, the present invention provides a defect differentiation method based on eddy current detection, comprising: Obtain the stress-voltage calibration curve of the calibration specimen and determine the standard defect-voltage relationship; Acquire voltage position test data of the test piece, compare the voltage position test data with the stress voltage calibration curve, and obtain a voltage position curve of the test piece; Compare the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, defect types include stress concentration defects, macro defects and coupling defects.

[0007] In a possible implementation, obtaining a stress-voltage calibration curve of a calibration specimen includes: Applying a detection signal to a first calibration specimen, and uniformly loading a tensile force on the first calibration specimen until it breaks, while recording first voltage-time data and tensile-time data of the first calibration specimen; Fitting the first voltage-time data and the tension-time data to obtain a stress-voltage calibration curve of the first calibration specimen; The first calibration specimen is made of the same material as the specimen to be tested, and the first calibration specimen has no defects.

[0008] In a possible implementation, determining a standard defect voltage relationship includes: Applying a detection signal to the defective test piece, and moving the defective test piece horizontally at a uniform speed, while recording the second voltage-time data and position-time data of the defective test piece; Fitting the second voltage-time data and the position-time data to obtain a defect voltage-position curve of the defective specimen; The defect voltage position curve is transformed based on the stress voltage calibration curve to obtain the stress position defect curve of the defective specimen; Determine the standard defect voltage relationship of the defect specimen based on the stress-position defect curve; Among them, the defect specimen is set with standard defects, which include stress concentration standard defects, macro standard defects and coupling standard defects; The standard defect voltage relationship is: a single peak of the stress position defect curve corresponds to a stress concentration standard defect; a single trough of the stress position defect curve corresponds to a macro standard defect; multiple continuous peaks and at least one trough of the stress position defect curve correspond to a coupled standard defect.

[0009] In a possible implementation manner, before applying the detection signal to the first calibration specimen, the method further includes: Constructing an eddy current detection device, the eddy current detection device comprising an excitation coil and a detection coil arranged coaxially; The excitation coil generates an excitation signal according to the detection signal and transmits the excitation signal to the detection coil; The detection coil acquires first voltage-time data according to the excitation signal.

[0010] In a possible implementation manner, after the detection coil acquires the first voltage-time data according to the excitation signal, the method further includes: The first voltage-time data is sequentially amplified by a primary amplifier circuit, a signal conditioning circuit and a secondary amplifier circuit.

[0011] In a possible implementation, obtaining voltage position test data of a device to be tested includes: Applying a detection signal to the device to be tested, and recording voltage data and corresponding position data of the device to be tested; The voltage data and position data are fitted to obtain voltage position test data.

[0012] In a possible implementation, recording the position data of the test piece includes: Construct a coordinate system; And determine the position data of the test piece based on the coordinate system.

[0013] In a possible implementation, comparing the voltage position test data with the stress voltage calibration curve to obtain the voltage position curve of the test piece includes: Determining a voltage reference value based on a stress voltage calibration curve; Based on the voltage reference value, the voltage position test data is subtracted to obtain a voltage position curve.

[0014] In a possible implementation, comparing the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece includes: The voltage position curve is transformed based on the stress voltage calibration curve to obtain a stress position test curve of the test piece; Capturing fluctuation data of a stress position test curve, the fluctuation data including stress fluctuation data and corresponding fluctuation position data; When the stress fluctuation data is single peak data, it is determined that the test piece has a stress concentration defect at a position corresponding to the fluctuation position data; When the stress fluctuation data is single trough data, it is determined that a macro standard defect exists in the test piece at a position corresponding to the fluctuation position data; When the stress fluctuation data includes a plurality of continuous wave crests and at least one wave trough, it is determined that a coupling standard defect exists in the test piece at a position corresponding to the fluctuation position data.

[0015] In order to solve the above problems, the present invention also provides a defect differentiation device based on eddy current detection, comprising: A standard determination module is used to obtain the stress-voltage calibration curve of the calibration specimen and determine the standard defect-voltage relationship; A voltage position curve acquisition module is used to acquire voltage position test data of the test piece, compare the voltage position test data with the stress voltage calibration curve, and obtain a voltage position curve of the test piece; Defect differentiation module, used to compare the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, defect types include stress concentration defects, macro defects and coupling defects.

[0016] The beneficial effect of adopting the above-mentioned embodiment is as follows: the present invention provides a defect differentiation method based on eddy current detection, firstly, by obtaining the stress-voltage calibration curve of the calibration specimen and determining the standard defect-voltage relationship, a judgment basis for subsequent defect differentiation is set; then, by obtaining the voltage position test data of the test piece, the voltage position test data and the stress-voltage calibration curve are compared to obtain the voltage position curve of the test piece, and the detection data of the test piece is converted to facilitate data comparison with the set judgment basis; finally, by comparing the voltage position curve and the standard defect voltage relationship, the defect type of the test piece is determined, thereby realizing direct determination of the defect type based on the eddy current detection data. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of a flow chart of an embodiment of a defect differentiation method based on eddy current detection provided by the present invention; Figure 2 A schematic diagram of a flow chart of an embodiment of obtaining a stress-voltage calibration curve of a calibration specimen provided by the present invention; Figure 3 A schematic diagram of the results of an embodiment of a stress voltage calibration curve provided by the present invention; Figure 4 A schematic diagram of a flow chart of an embodiment of determining a standard defect voltage relationship provided by the present invention; Figure 5 A schematic structural diagram of an embodiment of a defective test piece provided by the present invention; Figure 6 A schematic diagram of the result of an embodiment of a stress concentration defect provided by the present invention; Figure 7 A schematic diagram of the results of a macro defect embodiment provided by the present invention; Figure 8 A schematic diagram of the result of an embodiment of a coupling defect provided by the present invention; Fig. 9 A schematic diagram of a flow chart of an embodiment of determining the defect type of a test piece provided by the present invention; Fig.10 A judgment block diagram of an embodiment of determining the defect type of a test piece provided by the present invention; Fig.11 A structural block diagram of an embodiment of a defect differentiation device based on eddy current detection provided by the present invention; Fig.12 This is a structural block diagram of an embodiment of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0018] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0019] Eddy current testing (ET) is a non-destructive testing method based on the principle of electromagnetic induction. It is mainly suitable for surface and near-surface defect detection of conductive materials. The principle of eddy current testing is to use the electromagnetic induction phenomenon. When a coil with alternating current is placed on the metal plate to be tested or is wrapped around the metal tube to be tested, an alternating magnetic field will be generated in and near the coil. This alternating magnetic field will cause a vortex-shaped induced alternating current, i.e. eddy current, to be generated in the test piece. The distribution and size of the eddy current are related to factors such as the shape and size of the coil, the size and frequency of the alternating current, the conductivity, magnetic permeability, shape and size of the test piece, the distance from the coil, and the presence or absence of crack defects on the surface.

[0020] Stress concentration and macro defects in load-bearing steel structures can both lead to the risk of structural failure. Existing eddy current testing methods can effectively detect defects such as corrosion, cracks, and thinning of steel structures, and can also achieve a good assessment of the stress state of ferromagnetic materials. However, in the actual testing process, the material to be tested often contains both stress concentration and macro defects, and the defect area usually overlaps with the stress concentration area. Accurately detecting and identifying these two types of situations is an urgent need in the engineering field. Existing technologies only focus on the detection of defects or stresses alone, and there is no method that can effectively distinguish between macro defects and stress concentration areas.

[0021] Therefore, in the process of electromagnetic nondestructive testing of steel structures in the prior art, there is a problem that it is difficult to determine the defect type in a timely manner.

[0022] In order to solve the above problems, the present invention provides a defect differentiation method and device based on eddy current detection, which are described in detail below.

[0023] Figure 1 A schematic diagram of a flow chart of an embodiment of a defect differentiation method based on eddy current detection provided by the present invention, as shown in FIG. Figure 1 As shown, the defect differentiation method based on eddy current detection includes: S101: Obtain a stress-voltage calibration curve of a calibration specimen and determine a standard defect-voltage relationship; S102: acquiring voltage position test data of the test piece, comparing the voltage position test data with the stress voltage calibration curve, and obtaining a voltage position curve of the test piece; S103: comparing the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, defect types include stress concentration defects, macro defects and coupling defects.

[0024] In this embodiment, first, by obtaining the stress-voltage calibration curve of the calibration specimen and determining the standard defect-voltage relationship, a judgment basis for subsequent defect differentiation is set; then, by obtaining the voltage position test data of the test piece, the voltage position test data and the stress-voltage calibration curve are compared to obtain the voltage position curve of the test piece, and the detection data of the test piece is converted to facilitate data comparison with the set judgment basis; finally, by comparing the voltage position curve and the standard defect voltage relationship, the defect type of the test piece is determined, thereby realizing direct determination of the defect type based on eddy current detection data.

[0025] It should be noted that, in general, steel structures are tested in large quantities. Therefore, for the same material, it is only necessary to obtain the stress-voltage calibration curve of the calibration specimen once, that is, for the same material, the corresponding relationship between stress and voltage is consistent. Correspondingly, the relationship between standard defects and voltage is also consistent.

[0026] In addition, defect types include stress concentration defects, macro defects and coupling defects. Among them, stress concentration defects refer to the situation in which stress in steel structures is significantly increased due to factors such as the geometry of certain local areas, material defects or external loads; macro defects refer to visible defects inside or on the surface of steel caused by various factors (such as improper process selection or operation, non-metallic inclusions, gas, etc.) during the manufacturing or processing of steel structures. These defects may affect the mechanical properties, safety of use and overall quality of steel structures. Common types include: undercut, weld nodules, burn-through, shrinkage cavities, segregation, inclusions, cracks, etc.; coupling defects refer to the situation in which both concentrated defects and macro defects exist in a certain area of ​​the steel structure, and concentrated defects and macro defects appear alternately.

[0027] As a preferred embodiment, in S101, in order to obtain the stress voltage calibration curve of the calibration specimen, such as Figure 2 As shown, Figure 2 The schematic diagram of a flow chart of an embodiment of obtaining a stress-voltage calibration curve of a calibration specimen provided by the present invention includes: S201: applying a detection signal to a first calibration specimen, and uniformly loading a tensile force on the first calibration specimen until it breaks, while recording first voltage-time data and tensile-time data of the first calibration specimen; S202: fitting the first voltage-time data and the tension-time data to obtain a stress-voltage calibration curve of the first calibration specimen; The first calibration specimen is made of the same material as the specimen to be tested, and the first calibration specimen has no defects.

[0028] In this embodiment, by making targeted records of the first calibration specimen and analyzing the voltage conditions detected by the first calibration specimen when subjected to different tensile forces, a one-to-one correspondence between the tensile force of the steel structure and the voltage detected by the eddy current is achieved.

[0029] That is to say, since the steel structure will show different properties when subjected to different stresses, different voltage data can be obtained by performing eddy current testing on the steel structure. By calibrating the first calibration specimen, a standard comparison basis is obtained, which means that in the actual process of testing the steel structure, for any voltage data obtained, the stress condition corresponding to the voltage value can be inferred.

[0030] In a specific embodiment, if Figure 3 As shown, Figure 3 This is a result schematic diagram of an embodiment of the stress voltage calibration curve provided by the present invention, wherein the voltage change amount on the horizontal axis refers to the difference between the voltage data and the first detected voltage value, and the first detected voltage value is the subtrahend.

[0031] As a preferred embodiment, in S201, before applying the detection signal to the first calibration specimen, it also includes: first, constructing an eddy current detection device, the eddy current detection device includes an excitation coil and a detection coil arranged coaxially; then, the excitation coil generates an excitation signal according to the detection signal and transmits it to the detection coil; finally, the detection coil obtains first voltage-time data according to the excitation signal.

[0032] A detection signal is applied to the first calibration specimen through an eddy current detection device, the eddy current detection device includes an excitation coil and a detection coil, the excitation coil and the detection coil are coaxially arranged, and the radius of the detection coil is smaller than the excitation coil. The excitation coil excites an eddy current field on the surface of the first calibration specimen, and the detection coil picks up a voltage signal, thereby obtaining the first voltage-time data.

[0033] The optimal excitation frequency of the eddy current excitation coil is 5kHz.

[0034] In a specific embodiment, the excitation coil and the detection coil are both wound with enameled copper wire with a wire diameter of 0.08 mm, with 300 turns. The excitation coil has an outer diameter of 4 mm, an inner diameter of 3 mm, and a height of 3 mm; the eddy current detection coil has an outer diameter of 2 mm, an inner diameter of 1 mm, and a height of 3 mm.

[0035] The same material as the tested component is used as the first calibration specimen for stress detection. The probe consisting of an excitation coil and a detection coil is placed on the first calibration specimen, and the signal generator is adjusted to output a sinusoidal signal with a frequency of 5kHz and loaded onto the eddy current excitation coil. The first calibration specimen is uniformly loaded with tensile force by a tensile machine until the specimen breaks.

[0036] Among them, the continuous change of the force on the first calibration specimen will cause the induced voltage on the detection coil to change accordingly, and the output signal of the detection coil is finally displayed on the industrial computer through the primary amplifier circuit, signal conditioning circuit and secondary amplifier circuit. The curve of the tensile force on the specimen changing with time and the curve of the output voltage signal changing with time are recorded respectively to obtain the first voltage time data and tension time data.

[0037] In a specific embodiment, in order to improve the reliability of the first voltage-time data, the detection coil obtains the first voltage-time data according to the excitation signal, and then also includes: the first voltage-time data is amplified in sequence through a primary amplifier circuit, a signal conditioning circuit and a secondary amplifier circuit.

[0038] Further, in order to determine the standard defect voltage relationship, such as Figure 4 As shown, Figure 4 A flow chart of an embodiment of determining a standard defect voltage relationship provided by the present invention includes: S401: applying a detection signal to the defective test piece, and moving the defective test piece horizontally at a uniform speed, while recording second voltage-time data and position-time data of the defective test piece; S402: Fitting the second voltage-time data and the position-time data to obtain a defect voltage-position curve of the defective specimen; S403: transforming the defect voltage position curve based on the stress voltage calibration curve to obtain a stress position defect curve of the defective specimen; S404: determining a standard defect voltage relationship of the defective specimen according to the stress position defect curve; Among them, the defect specimen is set with standard defects, which include stress concentration standard defects, macro standard defects and coupling standard defects; The standard defect voltage relationship is: a single peak of the stress position defect curve corresponds to a stress concentration standard defect; a single trough of the stress position defect curve corresponds to a macro standard defect; multiple continuous peaks and at least one trough of the stress position defect curve correspond to a coupled standard defect.

[0039] In this embodiment, a defective specimen is specially set up and eddy current detection is performed on the defective specimen to obtain the voltage condition of the defective specimen at any position. Then, the stress position defect curve of the defective specimen is obtained by fitting the position and voltage data, so as to determine the pressure condition of the set defect at the corresponding position, and by comprehensively comparing the pressure data at different positions, the stress position defect curve corresponding to a specific defect is determined, that is, the data representation of different defects on the stress position defect curve is determined, so that the representation can be used as a basis for distinguishing the defect type in the future.

[0040] As a preferred embodiment, the same material as the component to be tested is used as a standard test piece for defect detection, and a standard defect that meets the scale specified in engineering practice is made on the standard piece to obtain a defect test piece. The signal generator is adjusted to output a sinusoidal signal with a frequency of 5kHz, and the output voltage of the detection coil changes due to the disturbance of the eddy current in the eddy current area. The voltage signal is processed and displayed through the primary amplifier circuit, the signal conditioning circuit and the secondary amplifier circuit to obtain the second voltage time data and position time data of the defective test piece.

[0041] In a specific embodiment, a probe composed of an excitation coil and a detection coil is horizontally scanned on the component to be tested, and the waveform displayed on the industrial computer is observed. According to different signal characteristics, it is judged whether there is stress concentration or defect in the area where the probe passes. If the output signal first drops sharply and then rises sharply to the amplitude before the mutation, forming a trough, this area is a defective area. If the output signal first rises slowly and then slowly drops back to the amplitude before the change, forming a peak, the area where the waveform is raised is the stress concentration area. If the output signal rises first and then falls twice in a row, and the value of the lowest point of the waveform is much smaller than the value when the signal does not change, this area is a coupling area of ​​stress concentration and defects, and the trough position is a defective area.

[0042] In order to better reflect the structure of the defective specimen and the positional relationship between the various structures when detecting the defective specimen, Figure 5 As shown, Figure 5 This is a schematic structural diagram of an embodiment of a defective specimen provided by the present invention, wherein a stress concentration defect 501, a macro defect 502 and a coupling defect 503 are respectively provided on the defective specimen 500, and during the detection process, an excitation coil 504 and a detection coil 505 are relatively fixedly arranged on the same side of the defective specimen 500, and the defective specimen 500 moves relative to the excitation coil 504 and the detection coil 505 to realize defect detection and record the detection data.

[0043] As a preferred embodiment, in S102, in order to obtain the voltage position test data of the test piece, first, a detection signal is applied to the test piece, and the voltage data and the corresponding position data of the test piece are recorded; then, the voltage data and the position data are fitted to obtain the voltage position test data.

[0044] In this embodiment, by performing eddy current detection on the test piece, the corresponding voltage data of the test piece is obtained. It should be noted that, since the data that can be directly obtained during the eddy current detection process only includes voltage data, in order to accurately classify the voltage data so as to determine the position corresponding to the abnormal voltage data, it is also necessary to record the position data at the same time, and then fit the voltage data and the position data to obtain the voltage position test data, that is, to determine the voltage data at a specific position of the steel structure.

[0045] In a specific embodiment, in order to better mark the position of the test piece, before recording the position data of the test piece, it is necessary to first construct a coordinate system, and then determine the position data of the test piece based on the coordinate system.

[0046] Furthermore, after obtaining the voltage position test data, it is necessary to compare the voltage position test data and the stress voltage calibration curve to obtain the voltage position curve of the test piece. Specifically, first, the voltage reference value is determined based on the stress voltage calibration curve; then, based on the voltage reference value, the voltage position test data is subtracted to obtain the voltage position curve.

[0047] In this embodiment, the normal voltage value of a specific steel structure, namely the voltage reference value, is determined by taking the stress voltage calibration curve as a reference. Then, the voltage reference value is used as a subtrahend and the voltage data in the voltage position test data is used as a minuend. By performing a difference, the voltage position test data is updated to obtain a voltage position curve.

[0048] In a specific embodiment, if Figure 6 As shown, Figure 6 A result schematic diagram of an embodiment of a stress concentration defect provided by the present invention, wherein the voltage change on the ordinate refers to the difference between the voltage data and the first detected voltage value, the first detected voltage value is a subtrahend, and the voltage change suddenly increases and persists at multiple positions, indicating that stress concentration exists at that position.

[0049] and Figure 6 Similar, such as Figure 7 As shown, Figure 7 A schematic diagram of the result of a macro defect embodiment provided by the present invention, such as Figure 8 As shown, Figure 8 A schematic diagram of the result of a coupling defect embodiment provided by the present invention.

[0050] In this embodiment, by associating the voltage data with the scanning position, it is possible to directly determine the defect type based on the voltage data.

[0051] As a preferred embodiment, in S103, in order to compare the voltage position curve with the standard defect voltage relationship, the defect type of the test piece is determined, such as Fig. 9 As shown, Fig. 9 A schematic diagram of a flow chart of an embodiment of determining the defect type of a test piece provided by the present invention includes: S901: transforming the voltage position curve based on the stress voltage calibration curve to obtain a stress position test curve of the test piece; S902: Capturing fluctuation data of a stress position test curve, where the fluctuation data includes stress fluctuation data and corresponding fluctuation position data; S903: When the stress fluctuation data is single peak data, determining that the test piece has a stress concentration defect at a position corresponding to the fluctuation position data; S904: when the stress fluctuation data is single trough data, determining that a macro standard defect exists in the test piece at a position corresponding to the fluctuation position data; S905: When the stress fluctuation data includes a plurality of continuous wave crests and at least one wave trough, it is determined that a coupling standard defect exists in the test piece at a corresponding position of the fluctuation position data.

[0052] In this embodiment, the voltage-position curve is transformed based on the stress-voltage calibration curve to obtain an intuitive stress-position relationship diagram, and then the defect type of the test piece is determined by capturing the fluctuation data.

[0053] In a specific embodiment, if Fig.10 As shown, Fig.10 A judgment block diagram of an embodiment of determining the defect type of a test piece provided by the present invention.

[0054] Through the above method, first, by obtaining the stress-voltage calibration curve of the calibration specimen and determining the standard defect voltage relationship, a judgment basis for subsequent defect differentiation is set; then, by obtaining the voltage position test data of the test piece, the voltage position test data and the stress-voltage calibration curve are compared to obtain the voltage position curve of the test piece, and the detection data of the test piece is converted to facilitate data comparison with the set judgment basis; finally, by comparing the voltage position curve and the standard defect voltage relationship, the defect type of the test piece is determined, thereby realizing direct determination of the defect type based on eddy current detection data.

[0055] In order to solve the above problems, the present invention also provides a defect distinguishing device based on eddy current detection, such as Fig.11 As shown, Fig.11 This is a structural block diagram of an embodiment of a defect differentiation device based on eddy current detection provided by the present invention. The defect differentiation device based on eddy current detection 1100 includes: The standard determination module 1101 is used to obtain the stress-voltage calibration curve of the calibration specimen and determine the standard defect-voltage relationship; The voltage position curve acquisition module 1102 is used to acquire voltage position test data of the test piece, compare the voltage position test data with the stress voltage calibration curve, and obtain the voltage position curve of the test piece; The defect differentiation module 1103 is used to compare the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, defect types include stress concentration defects, macro defects and coupling defects.

[0056] like Fig.12As shown, the present invention also provides an electronic device 1200. The electronic device 1200 includes a processor 1201, a memory 1202 and a display 1203. Fig.12 Only some components of the electronic device 1200 are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0057] In some embodiments, the processor 1201 may be a central processing unit (CPU), a microprocessor or other data processing chip, used to run program codes or process data stored in the memory 1202, such as the defect differentiation method based on eddy current detection in the present invention.

[0058] In some embodiments, the processor 1201 may be a single server or a server group. The server group may be centralized or distributed. In some embodiments, the processor 1201 may be local or remote. In some embodiments, the processor 1201 may be implemented in a cloud platform. In one embodiment, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an internal cloud, a multi-cloud, etc., or any combination thereof.

[0059] In some embodiments, the memory 1202 may be an internal storage unit of the electronic device 1200, such as a hard disk or memory of the electronic device 1200. In other embodiments, the memory 1202 may also be an external storage device of the electronic device 1200, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc., equipped on the electronic device 1200.

[0060] Furthermore, the memory 1202 may include both an internal storage unit of the electronic device 1200 and an external storage device. The memory 1202 is used to store application software installed in the electronic device 1200 and various data.

[0061] In some embodiments, the display 1203 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch device, etc. The display 1203 is used to display information of the electronic device 1200 and to display a visual user interface. The components 1201-1203 of the electronic device 1200 communicate with each other via a system device bus.

[0062] In one embodiment, when the processor 1201 executes the defect differentiation program based on eddy current detection in the memory 1202, the following steps may be implemented: Obtain the stress-voltage calibration curve of the calibration specimen and determine the standard defect-voltage relationship; Acquire voltage position test data of the test piece, compare the voltage position test data with the stress voltage calibration curve, and obtain a voltage position curve of the test piece; Compare the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, defect types include stress concentration defects, macro defects and coupling defects.

[0063] It should be understood that: when the processor 1201 executes the defect differentiation program based on eddy current detection in the memory 1202, in addition to the above functions, other functions can also be implemented. For details, please refer to the description of the corresponding method embodiment above.

[0064] Furthermore, the embodiment of the present invention does not specifically limit the type of the electronic device 1200 mentioned, and the electronic device 1200 may be a portable electronic device such as a mobile phone, a tablet computer, a personal digital assistant (PDA), a wearable device, a laptop computer, etc. Exemplary embodiments of portable electronic devices include but are not limited to portable electronic devices equipped with IOS, Android, Microsoft or other operating system devices. The above-mentioned portable electronic device may also be other portable electronic devices, such as a laptop computer with a touch-sensitive surface (e.g., a touch panel). It should also be understood that in some other embodiments of the present invention, the electronic device 1200 may not be a portable electronic device, but a desktop computer with a touch-sensitive surface (e.g., a touch panel).

[0065] Correspondingly, an embodiment of the present invention also provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, it can implement the steps or functions of the defect differentiation method based on eddy current detection provided in the above-mentioned method embodiments.

[0066] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware (such as a processor, a controller, etc.) through a computer program, and the computer program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0067] The defect differentiation method and device based on eddy current detection provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for technical personnel in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A defect differentiation method based on eddy current detection, characterized in that: include: Obtain the stress-voltage calibration curve of the calibration specimen and determine the standard defect-voltage relationship; Acquiring voltage position test data of the test piece, comparing the voltage position test data with the stress voltage calibration curve, and obtaining a voltage position curve of the test piece; Comparing the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, the defect types include stress concentration defects, macro defects and coupling defects.

2. The defect differentiation method based on eddy current detection according to claim 1 is characterized in that: The step of obtaining a stress-voltage calibration curve of the calibration specimen comprises: Applying a detection signal to a first calibration specimen, and uniformly loading a tensile force on the first calibration specimen until the specimen breaks, while recording first voltage-time data and tensile-time data of the first calibration specimen; Fitting the first voltage-time data and the tension-time data to obtain a stress-voltage calibration curve of the first calibration specimen; The first calibration specimen is made of the same material as the specimen to be tested, and the first calibration specimen has no defects.

3. The defect differentiation method based on eddy current detection according to claim 2 is characterized in that: The step of determining the standard defect voltage relationship comprises: Applying a detection signal to the defective test piece, and moving the defective test piece horizontally at a uniform speed, while recording second voltage-time data and position-time data of the defective test piece; Fitting the second voltage-time data and the position-time data to obtain a defect voltage-position curve of the defective specimen; The defect voltage position curve is transformed based on the stress voltage calibration curve to obtain a stress position defect curve of the defective specimen; Determining a standard defect voltage relationship of the defect specimen according to the stress position defect curve; Wherein, the defective specimen is provided with standard defects, and the standard defects include stress concentration standard defects, macro standard defects and coupling standard defects; The standard defect voltage relationship is: a single peak of the stress position defect curve corresponds to the stress concentration standard defect; a single trough of the stress position defect curve corresponds to the macro standard defect; multiple continuous peaks and at least one trough of the stress position defect curve correspond to the coupling standard defect.

4. The defect differentiation method based on eddy current detection according to claim 2 is characterized in that: Before applying the detection signal to the first calibration specimen, the method further includes: Constructing an eddy current detection device, the eddy current detection device comprising an excitation coil and a detection coil arranged coaxially; The excitation coil generates an excitation signal according to the detection signal and transmits the excitation signal to the detection coil; The detection coil acquires the first voltage-time data according to the excitation signal.

5. The defect differentiation method based on eddy current detection according to claim 2 is characterized in that: The first voltage-time data is acquired by the detection coil according to the excitation signal, and then the method further includes: The first voltage-time data is sequentially amplified by a primary amplifier circuit, a signal conditioning circuit and a secondary amplifier circuit.

6. The defect differentiation method based on eddy current detection according to claim 1 is characterized in that: The step of obtaining voltage position test data of the device to be tested includes: Applying a detection signal to the device to be tested, and recording voltage data and corresponding position data of the device to be tested; The voltage data and the position data are fitted to obtain the voltage position test data.

7. The defect differentiation method based on eddy current detection according to claim 5 is characterized in that: Recording the position data of the test piece includes: Construct a coordinate system; And the position data of the test piece is determined based on the coordinate system.

8. The defect differentiation method based on eddy current detection according to claim 1 is characterized in that: The comparing the voltage position test data with the stress voltage calibration curve to obtain the voltage position curve of the test piece includes: Determining a voltage reference value based on the stress voltage calibration curve; The voltage position test data is subtracted based on the voltage reference value to obtain the voltage position curve.

9. The defect differentiation method based on eddy current detection according to claim 1, characterized in that: The comparing the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece includes: The voltage position curve is transformed based on the stress voltage calibration curve to obtain a stress position test curve of the test piece; Capturing fluctuation data of the stress position test curve, wherein the fluctuation data includes stress fluctuation data and corresponding fluctuation position data; When the stress fluctuation data is single peak data, determining that the stress concentration defect exists in the test piece at a position corresponding to the fluctuation position data; When the stress fluctuation data is single trough data, determining that the macro standard defect exists in the test piece at a position corresponding to the fluctuation position data; When the stress fluctuation data includes a plurality of continuous wave crests and at least one wave trough, it is determined that the coupling standard defect exists in the test piece at a position corresponding to the fluctuation position data.

10. A defect differentiation device based on eddy current detection, characterized in that: include: A standard determination module is used to obtain the stress-voltage calibration curve of the calibration specimen and determine the standard defect-voltage relationship; A voltage position curve acquisition module is used to acquire voltage position test data of the test piece, compare the voltage position test data with the stress voltage calibration curve, and obtain the voltage position curve of the test piece; A defect differentiation module, used for comparing the voltage position curve with the standard defect voltage relationship to determine the defect type of the test piece; Among them, the defect types include stress concentration defects, macro defects and coupling defects.

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