Rapid defect imaging method and system

Abstract

The invention relates to the technical field of ultrasonic defect imaging, in particular to a rapid defect imaging method and system. The rapid defect imaging method comprises the following steps: according to a preset path, driving a displacement assembly to move according to a preset step length, and traversing each scanning position on the preset path; the preset path comprises a plurality of scanning positions; under the condition that the displacement assembly reaches the scanning position, the ultrasonic output assembly is controlled to send out detection ultrasound to the to-be-detected workpiece; controlling the electromagnetic ultrasonic one-way transducer to obtain an echo signal generated by ultrasonic detection; extracting a first echo signal in the echo signal along the to-be-detected direction; the to-be-detected direction is any direction, perpendicular to a preset path, of the electromagnetic ultrasonic one-way transducer; based on a synthetic aperture imaging algorithm of a frequency domain and the first echo signal, a defect image corresponding to the first echo signal is constructed, and the defect image comprises defect position information. The damage position of the surface of the to-be-detected workpiece can be determined based on the one-way echo, and the surface image of the to-be-detected workpiece can be further constructed.

Description

Technical Field

[0001] The present application relates to the technical field of ultrasonic defect imaging, and in particular to a method and system for rapid defect imaging. Background Art

[0002] Currently, after the production of a workpiece is completed, it is generally necessary to detect surface damage of the workpiece to determine whether the workpiece has surface damage.

[0003] In the related art, surface waves are excited by combining laser excitation with electromagnetic ultrasound technology. When the surface waves contact defects on the surface of the workpiece, defect echoes are generated, so that the presence of defects on the surface of the workpiece can be determined based on the defect echoes.

[0004] However, the related technology is to simultaneously receive defect echo signals from both sides of the coil to detect damage on the workpiece surface. Therefore, the received defect echo cannot determine the damage direction on the workpiece surface, that is, it cannot determine the position of the defect relative to the receiving coil.

[0005] Therefore, it is urgent to propose a new method for constructing workpiece surface damage images to overcome the above technical problems. Summary of the invention

[0006] The embodiments of the present application provide a defect rapid imaging method and system, which can determine the damage position on the surface of the workpiece to be measured based on a one-way echo, and further can construct a surface image of the workpiece to be measured.

[0007] In some embodiments, a defect rapid imaging method is provided, and the defect rapid imaging method is used in a defect rapid imaging system, the defect rapid imaging system includes a displacement component, an ultrasonic output component and an electromagnetic ultrasonic unidirectional transducer, and the workpiece to be measured is set on the displacement component; the defect rapid imaging method includes: according to a preset path, driving the displacement component to move according to a preset step length, traversing each scanning position on the preset path; the preset path includes multiple scanning positions; when the displacement component reaches the scanning position, controlling the ultrasonic output component to send a detection ultrasound to the workpiece to be measured; controlling the electromagnetic ultrasonic unidirectional transducer to obtain an echo signal generated by the detection ultrasound; extracting the first echo signal along the direction to be detected in the echo signal; the direction to be detected is any direction of the electromagnetic ultrasonic unidirectional transducer perpendicular to the preset path; based on the frequency domain synthetic aperture imaging algorithm and the first echo signal, constructing a defect image corresponding to the first echo signal, the defect image contains defect position information.

[0008] By using the defect rapid imaging method provided in the embodiment of the present application, damage detection of the surface of the workpiece to be tested is realized based on the detection of one-way echo of ultrasound, and the damage position of the surface of the workpiece to be tested can be determined based on the one-way echo, and the surface image of the workpiece to be tested can be further constructed. The detection accuracy of damage to the workpiece to be tested is increased, the detection time of damage to the surface of the workpiece to be tested is reduced, and the efficiency of detecting damage to the surface of the workpiece to be tested is improved.

[0009] Optionally, the electromagnetic ultrasonic unidirectional transducer includes a first coil and a second coil; extracting a first echo signal along a direction to be detected from the echo signal includes: determining a first voltage signal and a second voltage signal corresponding to the detected ultrasound; the first voltage signal is obtained by inducing the echo signal by the first coil, and the second voltage signal is obtained by inducing the echo signal by the second coil; based on a delay technology, determining a third voltage signal corresponding to the first voltage signal, the third voltage signal being a first phase delay of the first voltage signal Obtained; based on the superposition technology, determine the fourth voltage signal corresponding to the second voltage signal and the third voltage signal, the fourth voltage signal is obtained by superimposing the third voltage signal with the second voltage signal; the first echo signal includes the fourth voltage signal in the direction to be detected.

[0010] Optionally, the echo signal includes a first echo signal in a direction to be detected and a second echo signal in a direction opposite to the direction to be detected; the first phase of the first voltage signal is The second phase of the second voltage signal is In the case where the echo signal is the first echo signal, In the case where the echo signal is the second echo signal,

[0011] Optionally, when the echo signal is a first echo signal, the third voltage signal includes a first sub-signal; and the first voltage signal is: The first sub-signal is:

[0012] Optionally, the fourth voltage signal includes a third sub-signal; and the second voltage signal is: The third sub-signal is:

[0013] Optionally, when the echo signal is the second echo signal, the third voltage signal includes the second sub-signal; and the first voltage signal is: The second sub-signal is:

[0014] Optionally, the fourth voltage signal includes a fourth sub-signal; and the second voltage signal is: The fourth sub-signal is: u2=0.

[0015] Optionally, based on a synthetic aperture imaging algorithm in the frequency domain and the first echo signal, a defect image corresponding to the first echo signal is constructed, including: preprocessing the first echo signal; the preprocessing includes noise reduction processing and interference removal processing; based on Fourier transform, determining the frequency domain signal corresponding to the first echo signal; superimposing and combining the frequency domain signals to determine the total frequency domain signal of the workpiece to be measured; based on an inverse Fourier transform, determining the time domain image corresponding to the total frequency domain signal; and visualizing the time domain image to determine the defect image.

[0016] In some embodiments, a defect rapid imaging system is provided, comprising: a displacement component, in which a workpiece to be measured is arranged; an ultrasonic output component, configured to emit detection ultrasound; an electromagnetic ultrasonic unidirectional transducer, arranged with the ultrasonic output component along a preset path perpendicular to the movement of the workpiece to be measured, and the electromagnetic ultrasonic unidirectional transducer is configured to receive an echo signal generated by the detection ultrasound; an electronic device, communicatively connected with the displacement component, the ultrasonic output component and the electromagnetic ultrasonic unidirectional transducer; the electronic device is configured to drive the displacement component to move according to a preset step length along the preset path, and traverse each scanning position on the preset path; the preset path includes multiple scanning positions; when the displacement component reaches the scanning position, the ultrasonic output component is controlled to emit detection ultrasound to the workpiece to be measured; the electromagnetic ultrasonic unidirectional transducer is controlled to obtain the echo signal generated by the detection ultrasound; the first echo signal along the direction to be detected in the echo signal is extracted; the direction to be detected is any direction of the electromagnetic ultrasonic unidirectional transducer perpendicular to the preset path; based on the frequency domain synthetic aperture imaging algorithm and the first echo signal, a defect image corresponding to the first echo signal is constructed, and the defect image contains defect position information.

[0017] It can be understood that the beneficial effects that can be achieved by the technical solution provided by the above-mentioned defect rapid imaging system can be referred to the beneficial effects in the defect rapid imaging method and any of its optional implementations, and will not be repeated here.

[0018] Optionally, the electromagnetic ultrasonic unidirectional transducer includes a first coil and a second coil; the distance between the first coil and the second coil is d, the wavelength of the detected ultrasound is λ, and d=1 / 4λ. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 A structural block diagram of a defect rapid imaging system provided in an embodiment of the present application;

[0021] Figure 2A schematic diagram of the structure of a defect rapid imaging system provided in an embodiment of the present application;

[0022] Figure 3 A cross-sectional view of an electromagnetic ultrasonic unidirectional transducer provided in an embodiment of the present application;

[0023] Figure 4 A top view of a first coil and a second coil provided in an embodiment of the present application;

[0024] Figure 5 A flowchart of a defect rapid imaging method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be described clearly below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments of the present application, other embodiments obtained by ordinary technicians in this field without making creative work all belong to the protection scope of the present application.

[0026] In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0027] In addition, in the present application, directional terms such as "upper", "lower", "inner" and "outer" are defined relative to the orientation of the components schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to the changes in the orientation of the components placed in the drawings.

[0028] In order to facilitate the understanding of the technical solution of the application, the relevant technologies involved in this application are first explained below.

[0029] At present, after the production of the workpiece is completed, it is generally necessary to detect the surface damage of the workpiece to determine whether the workpiece has surface damage. In the related art, the use of laser to excite ultrasound has the characteristics of non-contact and high photoacoustic conversion efficiency. The use of electromagnetic ultrasonic transducers to receive ultrasound has the advantages of non-contact and low requirements on the surface state of the workpiece. Through the combination of laser excitation and electromagnetic ultrasonic technology, surface waves are stimulated. When the surface wave contacts the defects on the surface of the workpiece, a defect echo will be generated, so that the presence of defects on the workpiece surface can be determined based on the defect echo. However, the related art is to simultaneously receive the defect echo signals on both sides of the coil to realize damage detection on the workpiece surface. Therefore, the received defect echo cannot determine the direction of damage on the workpiece surface, that is, it cannot determine the position of the defect relative to the receiving coil.

[0030] In order to solve the above technical problems, the embodiments of the present application provide a defect rapid imaging method and system, which can detect damage on the surface of the workpiece to be tested based on the detection of one-way echoes of ultrasound, and can determine the damage position on the surface of the workpiece to be tested based on the one-way echo, and further can construct a surface image of the workpiece to be tested. The detection accuracy of damage to the workpiece to be tested is increased, the detection time of damage to the surface of the workpiece to be tested is reduced, and the efficiency of detecting damage to the surface of the workpiece to be tested is improved.

[0031] Figure 1 This is a structural block diagram of the defect rapid imaging system provided in an embodiment of the present application.

[0032] Combination Figure 1 As shown, an embodiment of the present application provides a defect rapid imaging system, comprising: a displacement component 10, an ultrasonic output component 20, an electromagnetic ultrasonic unidirectional transducer 30 and an electronic device 40. A workpiece 50 to be measured is arranged on the displacement component 10. The ultrasonic output component 20 is configured to emit detection ultrasound. The electromagnetic ultrasonic unidirectional transducer 30 and the ultrasonic output component 20 are arranged along a preset path perpendicular to the movement of the workpiece 50 to be measured, and the electromagnetic ultrasonic unidirectional transducer 30 is configured to receive the echo signal generated by the detection ultrasound. The electronic device 40 is communicatively connected with the displacement component 10, the ultrasonic output component 20 and the electromagnetic ultrasonic unidirectional transducer 30. The electronic device 40 is configured to drive the displacement component 10 to move according to the preset path, control the ultrasonic output component 20 to emit detection ultrasound, and obtain the echo signal received by the electromagnetic ultrasonic unidirectional transducer 30; according to the echo signal of the detection ultrasound in the direction to be detected, a defect image corresponding to the echo signal is constructed.

[0033] The defect rapid imaging system provided in the embodiment of the present application is adopted to control the displacement component 10, the ultrasonic output component 20 and the electromagnetic ultrasonic unidirectional transducer 30 to work in sequence according to the process through the electronic device 40 to collect the echo signal of the workpiece to be measured 50, so as to construct a defect image corresponding to the echo signal according to the echo signal of the detection direction of the ultrasonic detection to determine the position direction of the defect on the workpiece to be measured 50.

[0034] It should be understood that the electronic device 40 may be a computer (such as Figure 1 As long as the electronic device 40 can complete the damage detection of the workpiece to be tested according to the above process, the present application does not limit the specific type of the electronic device 40.

[0035] Figure 2 A schematic diagram of the structure of a defect rapid imaging system provided in an embodiment of the present application.

[0036] Specifically, in order to facilitate the understanding of the embodiments of the present application, Figure 2 An xyz coordinate system is constructed in . Exemplarily, the direction to be detected is the positive direction of the x-axis, and the opposite direction to be detected is the negative direction of the x-axis.

[0037] Exemplarily, in the embodiment of the present application, the preset path is a preset distance along the y-axis direction, and the size of the preset distance is determined according to the size of the workpiece 50 to be tested. For example, if the detection length of each ultrasonic detection is 5 cm, and the length of the workpiece 50 to be tested along the y-axis is 10 cm, at least two scanning positions are set on the preset path to obtain the echo signal of the entire workpiece 50 to be tested, and the preset distance is at least 5 cm (i.e., the distance between the first scanning position and the last scanning position).

[0038] Exemplarily, the electromagnetic ultrasonic unidirectional transducer 30 and the ultrasonic output assembly 20 are arranged along a preset path perpendicular to the movement of the workpiece 50 to be measured, that is, they are arranged in sequence along the x-axis.

[0039] Optionally, combined Figure 2 As shown, the displacement assembly 10 includes: a stepper motor driver 101, a stepper motor 102 and a displacement platform 103. The stepper motor driver 101 is connected to the electronic device 40 and the stepper motor 102 in communication, and the stepper motor driver 101 is configured to receive instructions from the electronic device 40 to control the rotation of the stepper motor 102. The stepper motor 102 is configured to be connected to the displacement platform 103, and the stepper motor 102 rotates to drive the displacement platform 103 to move.

[0040] Optionally, combined Figure 2As shown, the ultrasonic output component 20 includes: a pulse laser 201, an energy transmission optical fiber 202 and an ultrasonic excitation probe 203. The electronic device 40 is connected to the pulse laser 201 for communication. The electronic device 40 is configured to output a detection ultrasonic emission instruction to the pulse laser 201 to control the pulse laser 201 to emit a light pulse. The light pulse is transmitted to the ultrasonic excitation probe 203 through the energy transmission optical fiber 202 to emit a detection ultrasonic wave.

[0041] Figure 3 A cross-sectional view of an electromagnetic ultrasonic unidirectional transducer provided in an embodiment of the present application.

[0042] Figure 4 A top view of the first coil and the second coil provided in an embodiment of the present application.

[0043] Optionally, combined Figure 3 and Figure 4 As shown, the electromagnetic ultrasonic unidirectional transducer 30 includes a magnet 301, a first coil 302 and a second coil 303. The magnet 301 is configured to provide a magnetic field to the first coil 302 and the second coil 303. The first coil 302 is configured to induce an echo signal to obtain a first voltage signal, and the second coil 303 is configured to induce an echo signal to obtain a second voltage signal. Exemplarily, Figure 3 The cross dots in the first coil 302 and the second coil 303 represent the flow rate of the current.

[0044] Optionally, combined Figure 3 and Figure 4 As shown, the distance between the first coil 302 and the second coil 303 is d, the wavelength of the detected ultrasound is λ, and d=1 / 4λ.

[0045] Optionally, combined Figure 2 As shown, the electronic device 40 also includes a delay and superposition module 401, an amplification and filtering module 402 and a data processing module 403. The delay and superposition module 401 is connected to the electromagnetic ultrasonic unidirectional transducer 30 for communication. The delay and superposition module 401 is configured to receive the first voltage signal and the second voltage signal output by the electromagnetic ultrasonic unidirectional transducer 30, and is also configured to determine a third voltage signal corresponding to the first voltage signal based on the delay technology, and the third voltage signal is a first phase delay of the first voltage signal. Obtained; Based on the superposition technology, determine the fourth voltage signal corresponding to the second voltage signal and the third voltage signal, the fourth voltage signal is obtained by superimposing the third voltage signal and the second voltage signal; the fourth voltage signal corresponding to the second echo signal is 0. The amplification and filtering module 402 is connected to the delay and superposition module 401 and the data processing module 403 for communication. The amplification and filtering module 402 is configured to obtain the fourth voltage signal output by the delay and superposition module 401, and is also configured to amplify and filter the fourth voltage signal, and output it to the data processing module 403. The data processing module 403 is configured to construct a defect image corresponding to the fourth voltage signal according to the fourth voltage signal of the direction to be detected by the detection ultrasound.

[0046] Optionally, the data processing module 403 is communicatively connected to the pulse laser 201 and the stepper motor driver 101 .

[0047] Figure 5 A flowchart of a defect rapid imaging method provided in an embodiment of the present application.

[0048] Combination Figures 1 to 4 The defect rapid imaging system shown in the figure, the embodiment of the present application also provides a defect rapid imaging method, the execution subject of the method can be an electronic device, such as Figure 5 As shown, the defect rapid imaging method includes steps S100 to S500, which are specifically as follows:

[0049] Step S100, according to a preset path, drive the displacement component to move according to a preset step length, and traverse each scanning position on the preset path; the preset path includes multiple scanning positions.

[0050] In this step, multiple scanning positions are set on a preset path, so that detection ultrasound is emitted at each scanning position, and echo signals at each ultrasound position are obtained, thereby realizing surface damage detection of the workpiece to be detected.

[0051] For example, in combination Figure 2 As shown, in the embodiment of the present application, the preset path is a preset distance along the y-axis direction. The preset step length is less than or equal to the single detection length of the ultrasonic detection. After the displacement component is driven to move according to the preset step length, the displacement component moves from the previous scanning position to the next scanning position.

[0052] Specifically, combined Figure 2 As shown, in step S100, the computing device 40 sends a control movement instruction to the stepper motor driver 101 to control the rotation of the stepper motor 102. The stepper motor 102 is configured to be connected to the displacement platform 103, and the stepper motor 102 rotates to drive the displacement platform 103 to move, thereby driving the workpiece 50 to move.

[0053] Step S200, when the displacement component reaches the scanning position, the ultrasonic output component is controlled to emit detection ultrasound to the workpiece to be measured.

[0054] In this step, when the displacement assembly reaches the scanning position, a detection ultrasound is emitted to the workpiece to be tested, so as to obtain a partial echo signal of the workpiece to be tested corresponding to the current scanning position. Thus, after completely traversing each scanning position, the complete echo signal of the workpiece to be tested is obtained, thereby realizing the surface damage detection of the workpiece to be tested.

[0055] Specifically, combined Figure 2 As shown, in step S200, the computing device 40 sends a detection ultrasound emission instruction to the pulse laser 201 to control the pulse laser 201 to emit a light pulse. The light pulse is transmitted to the ultrasound excitation probe 203 through the energy transmission optical fiber 202 to emit the detection ultrasound.

[0056] Step S300, controlling the electromagnetic ultrasonic unidirectional transducer to acquire the echo signal generated by the detection ultrasound.

[0057] In this step, when the displacement assembly reaches the scanning position, the detection ultrasound is first sent to the workpiece to be tested, so as to generate an echo signal after the detection ultrasound contacts the damage of the workpiece to be tested, thereby determining whether the workpiece to be tested has damage according to the echo signal obtained by the electromagnetic ultrasonic unidirectional transducer.

[0058] Specifically, combined Figure 2 As shown, in step S300, the computing device 40 sends an echo acquisition instruction to the electromagnetic ultrasonic unidirectional transducer 30, and the electromagnetic ultrasonic unidirectional transducer 30 sends the induced voltage (first voltage signal and second voltage signal) of the first coil 302 and the second coil 303 to the electronic device to achieve the acquisition of the echo signal.

[0059] Step S400, extracting the first echo signal along the direction to be detected from the echo signal; the direction to be detected is any direction of the electromagnetic ultrasonic unidirectional transducer perpendicular to the preset path (for example Figure 2 positive x-axis as shown).

[0060] In this step, by extracting the first echo signal along the direction to be detected from the echo signal, the signal on one side of the electromagnetic ultrasonic unidirectional transducer is obtained, thereby facilitating confirmation of the damage direction corresponding to the echo signal.

[0061] Specifically, since the first echo signal is an echo signal along the direction to be detected, the distance between the damage in the direction to be detected and the electromagnetic ultrasonic unidirectional transducer can be determined based on the first echo signal, and combined with the scanning position when the electromagnetic ultrasonic unidirectional transducer receives the echo signal, the position where the damage is located on the surface of the workpiece to be detected can be determined.

[0062] Optionally, combined Figure 3and Figure 4 As shown, the electromagnetic ultrasonic unidirectional transducer 30 includes a first coil 302 and a second coil 303. Step S400 includes steps S401 to S403, which are specifically as follows:

[0063] Step S401, determining a first voltage signal and a second voltage signal corresponding to the detected ultrasound; the first voltage signal is obtained by inducing an echo signal by the first coil, and the second voltage signal is obtained by inducing an echo signal by the second coil.

[0064] In this step, after the echo signal is transmitted to the first coil and the second coil, the induced voltage of the first coil is a first voltage signal, and the induced voltage of the second coil is a second voltage signal, thereby extracting the first echo signal along the direction to be detected based on the first voltage signal and the second voltage signal.

[0065] Step S402: Based on the delay technology, determine a third voltage signal corresponding to the first voltage signal, where the third voltage signal is a signal that delays the first phase of the first voltage signal. Got it.

[0066] Specifically, the third phase of the third voltage signal is equal to the first phase minus

[0067] For example, in combination Figure 2 As shown, step S402 is implemented by the delay and superposition module 401.

[0068] Step S403, based on the superposition technology, determine the fourth voltage signal corresponding to the second voltage signal and the third voltage signal, the fourth voltage signal is obtained by superimposing the third voltage signal and the second voltage signal; the first echo signal includes the fourth voltage signal in the direction to be detected.

[0069] In this embodiment, through the delay technology and superposition technology, the first voltage signal is delayed and then superimposed with the second voltage signal, so that the signal (first echo signal) propagating in the positive direction of the x-axis (the direction to be detected) is enhanced and the signal (second echo signal) propagating in the negative direction of the x-axis (opposite to the direction to be detected) is attenuated, thereby extracting the first echo signal.

[0070] Optionally, the echo signal includes a first echo signal in a direction to be detected and a second echo signal in a direction opposite to the direction to be detected; the first phase of the first voltage signal is The second phase of the second voltage signal is In the case where the echo signal is the first echo signal, In the case where the echo signal is the second echo signal,

[0071] In this embodiment, the phase difference between the first echo signal and the second echo signal is limited, so that after the first voltage signal is delayed and superimposed with the second voltage signal, the first echo signal (the echo signal in the direction to be detected) is strengthened, while the second echo signal (the echo signal in the opposite direction to be detected) is attenuated.

[0072] Optionally, after step S403, step S404 is further included:

[0073] Step S404, amplify and filter the fourth voltage signal, so as to increase the voltage strength of the fourth voltage signal, improve the signal-to-noise ratio of the fourth voltage signal, and eliminate noise in the fourth voltage signal.

[0074] Specifically, combined Figure 2 As shown, step S404 is implemented by the amplification and filtering module 402 .

[0075] Optionally, when the echo signal is a first echo signal, the third voltage signal includes a first sub-signal; and the first voltage signal is: The first sub-signal is:

[0076] In this embodiment, when the echo signal is the first echo signal (the direction is the direction to be detected), the first phase of the delayed first voltage signal is After that, the third phase of the third voltage signal (first sub-signal) is obtained as

[0077] Optionally, the fourth voltage signal includes a third sub-signal; and the second voltage signal is: The third sub-signal is:

[0078] In this embodiment, when the echo signal is the first echo signal, the fourth voltage signal obtained by superimposing the first sub-signal with the second voltage signal is the third sub-signal to obtain an enhanced third sub-signal, that is, to obtain an enhanced first echo signal (the echo signal in the direction to be detected).

[0079] Optionally, when the echo signal is the second echo signal, the third voltage signal includes the second sub-signal; and the first voltage signal is: The second sub-signal is:

[0080] In this embodiment, when the echo signal is the second echo signal (the direction is opposite to the direction to be detected), the first phase of the first voltage signal is delayed After that, the third phase of the third voltage signal (second sub-signal) is obtained as The amplitude of the third voltage signal is opposite to that of the second voltage signal. Specifically, due to the phase difference between the first pressure of the first voltage signal and the second pressure of the second voltage signal, Therefore, the second sub-signal obtained after delaying the first voltage signal is opposite to the second voltage signal, and after superimposing the second sub-signal and the second voltage signal, the fourth sub-signal obtained is 0, thereby achieving attenuation of the second echo signal and extracting the first echo signal from the echo signal.

[0081] Optionally, the fourth voltage signal includes a fourth sub-signal; and the second voltage signal is: The fourth sub-signal is: u2=0.

[0082] In this embodiment, when the echo signal is the second echo signal, the fourth voltage signal obtained by superimposing the second sub-signal with the second voltage signal is the fourth sub-signal, so as to obtain a fourth sub-signal attenuated to 0, that is, an attenuated second echo signal (the echo signal in the direction to be detected), thereby realizing the extraction of the first echo signal in the echo signal.

[0083] Step S500 : constructing a defect image corresponding to the first echo signal based on a frequency domain synthetic aperture imaging algorithm and the first echo signal, wherein the defect image includes defect position information.

[0084] Optionally, step S500 includes steps S501 to S505, which are specifically as follows:

[0085] Step S501, preprocessing the first echo signal; the preprocessing includes noise reduction processing and interference removal processing.

[0086] Step S502: Determine a frequency domain signal corresponding to the first echo signal based on Fourier transform.

[0087] Step S503: superimpose and combine the frequency domain signals to determine the total frequency domain signal of the workpiece to be measured.

[0088] Step S504: determining a time domain image corresponding to the total frequency domain signal based on inverse Fourier transform.

[0089] Step S505: Visualize the time domain image to determine the defect image.

[0090] In this embodiment, through steps S501 to S505, a defect image of the surface of the workpiece to be measured corresponding to the first echo signal can be constructed, thereby facilitating processing of the workpiece to be measured and other issues.

[0091] Specifically, the frequency domain-based synthetic aperture imaging algorithm is based on the back propagation theory, which regards each pixel as a sound source, thereby eliminating the propagation time of the ultrasonic wave from the excitation point to the pixel point, and requires that the excitation and receiving positions of the ultrasonic wave coincide. Therefore, the embodiment of the present application proposes to perform negative compensation on the sound path, subtract the distance between the excitation point and the center of the electromagnetic ultrasonic unidirectional transducer from the sound path, and regard the ultrasonic wave as being emitted from the center of the electromagnetic ultrasonic unidirectional transducer. Accordingly, the time domain signal is intercepted to obtain data for frequency domain-based synthetic aperture imaging.

[0092] By using the defect rapid imaging method provided in the embodiment of the present application, damage detection of the surface of the workpiece to be tested is realized based on the detection of one-way echo of ultrasound, and the damage position of the surface of the workpiece to be tested can be determined based on the one-way echo, and the surface image of the workpiece to be tested can be further constructed. The detection accuracy of damage to the workpiece to be tested is increased, the detection time of damage to the surface of the workpiece to be tested is reduced, and the efficiency of detecting damage to the surface of the workpiece to be tested is improved.

[0093] Corresponding to the above-mentioned embodiment of the defect rapid imaging method, Figure 1 As shown, the present application also provides an embodiment of a defect rapid imaging device. The defect rapid imaging device includes: a displacement component, an ultrasonic output component, an electromagnetic ultrasonic unidirectional transducer and an electronic device. The workpiece to be measured is arranged on the displacement component. The ultrasonic output component is configured to emit detection ultrasound. The electromagnetic ultrasonic unidirectional transducer and the ultrasonic output component are arranged along a preset path perpendicular to the movement of the workpiece to be measured, and the electromagnetic ultrasonic unidirectional transducer is configured to receive the echo signal generated by the detection ultrasound. The electronic device is communicatively connected with the displacement component, the ultrasonic output component and the electromagnetic ultrasonic unidirectional transducer. The electronic device is configured to drive the displacement component to move according to a preset step length along a preset path, and traverse each scanning position on the preset path; the preset path includes multiple scanning positions; when the displacement component reaches the scanning position, the ultrasonic output component is controlled to emit detection ultrasound to the workpiece to be measured; the electromagnetic ultrasonic unidirectional transducer is controlled to obtain the echo signal generated by the detection ultrasound; the first echo signal along the direction to be detected in the echo signal is extracted; the direction to be detected is any direction of the electromagnetic ultrasonic unidirectional transducer perpendicular to the preset path; based on the synthetic aperture imaging algorithm in the frequency domain and the first echo signal, a defect image corresponding to the first echo signal is constructed, and the defect image contains defect position information.

[0094] The defect rapid imaging system provided in the embodiment of the present application is used to achieve damage detection on the surface of the workpiece to be tested based on the one-way echo of the detection ultrasound through the cooperation between the displacement component, the ultrasonic output component, the electromagnetic ultrasonic one-way transducer and the electronic device, and can determine the damage position on the surface of the workpiece to be tested based on the one-way echo, and further can construct the surface image of the workpiece to be tested. The detection accuracy of the damage of the workpiece to be tested is increased, the detection time of the damage on the surface of the workpiece to be tested is reduced, and the efficiency of detecting the damage on the surface of the workpiece to be tested is improved.

[0095] Optionally, combined Figure 3 and Figure 4 As shown, the electromagnetic ultrasonic unidirectional transducer includes a first coil and a second coil; the distance between the first coil and the second coil is d, the wavelength of the detected ultrasound is λ, and d=1 / 4λ.

[0096] In this embodiment, the distance between the first coil and the second coil is limited so that the first voltage signal induced by the first coil and the second voltage signal induced by the second coil have a certain value. , thereby facilitating the extraction of the first echo signal from the echo signal.

[0097] For example, in combination Figure 2 As shown, Figure 2 The surface of the workpiece 50 to be tested shown has a first defect 501, a second defect 502 and a third defect 503, and the first defect 501, the second defect 502 and the third defect 503 are all crack defects. The aforementioned workpiece 50 to be tested is inspected and imaged, and the y-axis scanning length is set to 350 mm (that is, the path is set to include a path with a preset distance of 350 mm along the y-axis), and the scanning step length (preset step length) is 1 mm, and a total of 350 sets of ultrasonic data are obtained. The data are processed by the frequency domain-based synthetic aperture imaging algorithm and the traditional time domain B-scan imaging algorithm provided in the embodiment of the present application, respectively, which takes 0.057304 s and 0.291197 s respectively. The imaging speed of the former is 5 times that of the latter. It can be seen that the frequency domain-based synthetic aperture imaging algorithm has a faster speed. Especially when the amount of data is large, the defect rapid imaging method and system provided in the embodiment of the present application have more obvious advantages. In addition, the existing defect image construction method receives signals from both sides of the transducer at the same time, and can only identify the presence or absence of defects but cannot distinguish the specific direction of the defects. In comparison, the embodiments of the present application can provide the location of the defects.

[0098] It should be noted that those skilled in the art will easily think of other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary technical means in the art that are not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope of the present application is indicated by the claims.

[0099] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A defect rapid imaging method, characterized in that: The defect rapid imaging method is used in a defect rapid imaging system, which includes a displacement component, an ultrasonic output component and an electromagnetic ultrasonic unidirectional transducer, and the workpiece to be measured is arranged on the displacement component; The defect rapid imaging method comprises: According to a preset path, driving the displacement component to move according to a preset step length to traverse each scanning position on the preset path; The preset path includes a plurality of scanning positions; When the displacement component reaches the scanning position, controlling the ultrasonic output component to emit detection ultrasound to the workpiece to be measured; Controlling the electromagnetic ultrasonic unidirectional transducer to obtain the echo signal generated by the detection ultrasound; Extracting a first echo signal along a direction to be detected from the echo signal; the direction to be detected is any direction of the electromagnetic ultrasonic unidirectional transducer perpendicular to the preset path; Based on a frequency-domain synthetic aperture imaging algorithm and the first echo signal, a defect image corresponding to the first echo signal is constructed, wherein the defect image includes defect location information.

2. The defect rapid imaging method according to claim 1, characterized in that: The electromagnetic ultrasonic unidirectional transducer comprises a first coil and a second coil; the step of extracting the first echo signal along the direction to be detected from the echo signal comprises: Determine a first voltage signal and a second voltage signal corresponding to the detection ultrasound; the first voltage signal is obtained by the first coil sensing the echo signal, and the second voltage signal is obtained by the second coil sensing the echo signal; Based on the delay technology, a third voltage signal corresponding to the first voltage signal is determined, and the third voltage signal is a signal that delays the first phase of the first voltage signal. obtained; Based on the superposition technology, a fourth voltage signal corresponding to the second voltage signal and the third voltage signal is determined, and the fourth voltage signal is obtained by superimposing the third voltage signal and the second voltage signal; the first echo signal includes the fourth voltage signal in the direction to be detected.

3. The defect rapid imaging method according to claim 2, characterized in that: The echo signal includes the first echo signal in the direction to be detected and the second echo signal in the opposite direction to the direction to be detected; The first phase of the first voltage signal is The second phase of the second voltage signal is In a case where the echo signal is the first echo signal, In the case where the echo signal is the second echo signal, 4. The defect rapid imaging method according to claim 3, characterized in that: In the case where the echo signal is the first echo signal, the third voltage signal includes a first sub-signal; The first voltage signal is: The first sub-signal is:

5. The defect rapid imaging method according to claim 4, characterized in that: The fourth voltage signal includes a third sub-signal; The second voltage signal is: The third sub-signal is:

6. The defect rapid imaging method according to claim 3, characterized in that: In the case where the echo signal is the second echo signal, the third voltage signal includes a second sub-signal; The first voltage signal is: The second sub-signal is:

7. The defect rapid imaging method according to claim 6, characterized in that: The fourth voltage signal includes a fourth sub-signal; The second voltage signal is: The fourth sub-signal is: u2=0.

8. The defect rapid imaging method according to claim 1, characterized in that: The method of constructing a defect image corresponding to the first echo signal using the frequency domain-based synthetic aperture imaging algorithm and the first echo signal includes: Preprocessing the first echo signal; the preprocessing includes noise reduction processing and interference removal processing; Determine a frequency domain signal corresponding to the first echo signal based on Fourier transform; Superimposing and combining the frequency domain signals to determine the total frequency domain signal of the workpiece to be measured; Based on inverse Fourier transform, determining a time domain image corresponding to the total frequency domain signal; The time domain image is visualized to determine the defect image.

9. A defect rapid imaging system, characterized in that: include: A displacement assembly, wherein the workpiece to be measured is arranged on the displacement assembly; An ultrasonic output component configured to emit detection ultrasound; An electromagnetic ultrasonic unidirectional transducer is arranged with the ultrasonic output assembly along a preset path perpendicular to the movement of the workpiece to be tested, and the electromagnetic ultrasonic unidirectional transducer is configured to receive the echo signal generated by the detection ultrasound; An electronic device is communicatively connected with the displacement component, the ultrasonic output component and the electromagnetic ultrasonic unidirectional transducer; the electronic device is configured to drive the displacement component to move according to a preset step length along a preset path, and traverse each scanning position on the preset path; the preset path includes a plurality of the scanning positions; when the displacement component reaches the scanning position, the ultrasonic output component is controlled to emit detection ultrasound to the workpiece to be measured; the electromagnetic ultrasonic unidirectional transducer is controlled to obtain the echo signal generated by the detection ultrasound; the first echo signal along the direction to be detected in the echo signal is extracted; the direction to be detected is any direction of the electromagnetic ultrasonic unidirectional transducer perpendicular to the preset path; based on the synthetic aperture imaging algorithm in the frequency domain and the first echo signal, a defect image corresponding to the first echo signal is constructed, and the defect image contains defect position information.

10. The defect rapid imaging system according to claim 9, characterized in that: The electromagnetic ultrasonic unidirectional transducer comprises: a first coil and a second coil; The distance between the first coil and the second coil is d, the wavelength of the detection ultrasound is λ, and d=1 / 4λ.

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