Electromagnetic ultrasonic multi-mode detection sensor, device and debonding quality detection method

Abstract

The application discloses an electromagnetic ultrasonic multi-mode detection sensor, a device and a debonding quality detection method, wherein the sensor comprises a shell; a U-shaped permanent magnet composed of a first permanent magnet, a magnetic yoke and a second permanent magnet in sequence and arranged in the shell; a first excitation coil and a first receiving coil, both of which are arranged below the first permanent magnet; a second excitation coil and a second receiving coil, both of which are arranged directly below the U-shaped permanent magnet; and a connector arranged on the shell and divided into two paths, one of which is connected with the first excitation coil and the first receiving coil, and the other of which is connected with the second excitation coil and the second receiving coil. The sensor has the advantages of an electromagnetic ultrasonic guided wave sensor and an electromagnetic ultrasonic resonant sensor, and can be combined with a Barker code pulse compression technology to realize non-contact and non-coupling debonding quality rapid and efficient detection, quantitative detection of tiny debonding defects and improved detection precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of quality detection, and particularly relates to an electromagnetic ultrasonic multi-mode detection sensor, a device and a debonding quality detection method. BACKGROUND

[0002] The tail nozzle of a solid rocket engine is a composite structure composed of multiple materials, and is required to withstand high-temperature, high-speed and high-pressure thermal ablation and erosion in a harsh working environment. Therefore, each component is required to have high reliability. The metal shell of the tail nozzle and the non-metal bonding interface are prone to debonding due to the following reasons: the workpiece is not cleaned properly during bonding, the inner liner and the outer shell do not cooperate closely, and the gas in the glue layer is not completely discharged. In particular, large-area debonding of the gap type is extremely harmful to the reliability of the product. Therefore, nondestructive testing of the bonding quality of the bonding interface is also a key process for product quality control in the production of solid rocket engines. The bonding quality of the debonding structure of the expansion section of the tail nozzle directly affects the safety and reliability of the solid rocket engine during service and actual operation.

[0003] Disastrous accidents caused by poor bonding and interface defects such as pores often occur during the manufacture and use of the expansion section of the tail nozzle of a solid rocket engine. Therefore, detecting the debonding defect area of the expansion section of the solid rocket engine and improving the manufacturing process and storage conditions accordingly are beneficial to improving the safety, reliability and flight accuracy of the engine.

[0004] When using the ultrasonic pulse reflection method to detect the metal-composite double-layer structure of the expansion section of the tail nozzle, the metal produces a shielding effect, causing the acoustic energy to be concentrated in the metal layer and difficult to be transmitted. When using piezoelectric ultrasonic detection to detect the expansion section of the tail nozzle of a solid rocket engine, the liquid coupling agent such as water used for ultrasonic detection is easily immersed in the composite material, which seriously affects the quality of the composite material and causes potential threats. The commonly used composite material of the tail nozzle is carbon cloth and high-silicon cloth products. The above-mentioned materials are cured at high temperature, and gas is discharged during the process. There are pores in the product, and the liquid coupling agent such as water can enter the composite material, which is a redundant object and needs to be removed. In addition, the composite material will swell, and the original structure and shape will be damaged in severe cases. In addition, due to the special structure of the taper thin-walled metal of the expansion section of the tail nozzle of a solid rocket engine, such as the variable diameter / variable thickness, the probe and the tapered metal pipe are difficult to achieve good adhesion, the ultrasonic coupling efficiency is reduced, the acoustic transparency effect is poor, and the ultrasonic detection echo amplitude is greatly affected by the coupling condition of the coupling agent. A larger defect detection sensitivity needs to be set, which makes it difficult to detect smaller debonding defects, that is, it is difficult to quantitatively detect debonding defects. Therefore, a non-contact ultrasonic detection technology and method are urgently needed to realize rapid and efficient detection of the debonding quality of the expansion section of the tail nozzle of a solid rocket engine and to detect smaller debonding defects.

[0005] The existing technical solutions for solid rocket debonding detection are described as follows:

[0006] The invention patent application number CN202111282958.0 discloses a phased array piezoelectric ultrasonic imaging detection method and system for solid rocket engine II interface debonding, which utilizes ultrasonic echo signals, position signals provided by an encoder, and imaging gates to convert the maximum signal amplitude of the ultrasonic signals corresponding to the position points within the imaging gates into pixel points, and forms an ultrasonic C-mode image of the II interface according to the pixel points of the detection area.

[0007] The invention patent application number CN202110997413.1 discloses an ultrasonic detection method for debonding defects of a cylindrical thin-shell adhesive assembly of a pyrotechnic product, which utilizes the obvious attenuation characteristics of ultrasonic waves in rubber to detect debonding defects of the cylindrical thin-shell adhesive assembly of the pyrotechnic product. The ultrasonic probe used in the invention has the characteristics of narrow pulse, high frequency (10 MPa), and small chip size (Φ6), and can realize high-precision debonding defect detection (Φ3). The invention uses anhydrous ethanol as a coupling medium, which can avoid the use of water or oil as a coupling agent to pollute the workpiece. The invention is designed with a flexible coupling sleeve made of silicone rubber at the end, which can realize coupling agent injection coupling and can adapt to various diameter (Φ100-Φ300) thin-shell adhesive assembly rubber debonding detection, and is convenient for automatic scanning detection.

[0008] The invention patent application number CN202110623181.3 discloses a health monitoring method for artificial debonding layer interface debonding of a solid rocket engine, which is used for monitoring the root tear of the artificial debonding layer, the bottom layer interface debonding, and the cover layer interface debonding of the solid rocket engine. The invention uses a computer, a signal excitation device, a signal acquisition device, and a piezoelectric chip to form a monitoring system, obtains a high-frequency local vibration response signal that is more sensitive to the root tear of the artificial debonding layer, the bottom layer interface debonding, and the cover layer interface debonding, and realizes in-situ, real-time, online, and long-term monitoring of the artificial debonding layer.

[0009] The invention patent application number CN201810470104.7 discloses an ultrasonic detection method and system for low / high acoustic impedance bonding interfaces. A digital ultrasonic detection system and a longitudinal wave straight probe are used to perform ultrasonic detection on a workpiece; the echo signal is amplified and then subjected to ultrasonic wave full-wave train digital acquisition; the echo signal of the high acoustic impedance plate above one period after the bonding interface echo signal is selected by a gate as a characteristic echo; the characteristic value of the detection workpiece is determined; and the discrimination value is determined according to the detection echo characteristic values of the bonded and debonded parts on the comparative test block.

[0010] The prior art above all adopts a contact type detection mode needing coupling medium, has low detection efficiency, has a destructive effect on the workpiece by the coupling medium, has low detection precision, and is not sensitive enough to the detection of small debonding defects. SUMMARY

[0011] In view of the problems of low detection efficiency and destructive effect of the coupling agent on the workpiece in the traditional ultrasonic detection, the application provides an electromagnetic ultrasonic multi-mode detection sensor, device and debonding quality detection method, realizes non-contact and coupling-free rapid and efficient debonding quality detection, and improves detection precision.

[0012] In a first aspect, an electromagnetic ultrasonic multi-mode detection sensor is provided, comprising:

[0013] a shell;

[0014] a U-shaped permanent magnet composed of a first permanent magnet, a magnetic yoke and a second permanent magnet in sequence, arranged in the shell;

[0015] a first excitation coil and a first receiving coil, both arranged below the first permanent magnet;

[0016] a second excitation coil and a second receiving coil, both arranged directly below the U-shaped permanent magnet;

[0017] a connector arranged on the shell and divided into two paths, one path connecting the first excitation coil and the first receiving coil, and the other path connecting the second excitation coil and the second receiving coil.

[0018] According to the first aspect, in a possible implementation manner, the bottom of the first permanent magnet is provided with a copper plate.

[0019] According to the first aspect, in a possible implementation manner, the first excitation coil and the first receiving coil are spiral coils or racetrack coils.

[0020] According to the first aspect, in a possible implementation manner, the second excitation coil and the second receiving coil are both meander coils.

[0021] According to the first aspect, in a possible implementation manner, the first excitation coil, the first receiving coil, the second excitation coil and the second receiving coil are all made of a soft hard-brush circuit board.

[0022] According to the first aspect, in a possible implementation manner, symmetrical rolling bearings are arranged on the outer side of the shell.

[0023] In a second aspect, an electromagnetic ultrasonic multi-mode detection device is provided, comprising an industrial computer, a signal generator, a data acquisition card, a high-power pulse generator / receiver, a multi-channel switch, an impedance matching network, and an electromagnetic ultrasonic multi-mode detection sensor as described above.

[0024] The industrial computer is connected with the signal generator and the data acquisition card, and the signal generator and the data acquisition card are connected with the high-power pulse generator / receiver.

[0025] According to the second aspect, in a possible implementation, the device further comprises a servo motion control system and a rotating platform and a moving platform connected with the servo motion control system, the servo motion control system is connected with the industrial computer, and the electromagnetic ultrasonic multi-mode detection sensor is installed on the moving platform.

[0026] According to the second aspect, in a possible implementation, the moving platform comprises a moving base, a sliding support rod, and a spring assembly, one end of the sliding support rod is slidably installed on the moving base, the other end of the sliding support rod is rotatably connected with the electromagnetic ultrasonic multi-mode detection sensor, one end of the spring assembly is connected with the moving base, and the other end of the spring assembly is connected with the electromagnetic ultrasonic multi-mode detection sensor.

[0027] In a third aspect, a debonding quality detection method is provided, comprising:

[0028] S1: moving the electromagnetic ultrasonic multi-mode detection sensor as described above to an axial position of a to-be-detected member;

[0029] S2: passing a first excitation current signal into a second excitation coil to make the to-be-detected member generate ultrasonic guided waves propagating along a circumferential direction corresponding to the axial position, receiving an ultrasonic echo signal, and determining whether there is a debonding defect in the circumferential region corresponding to the axial position;

[0030] S3: if there is a debonding defect in the circumferential region corresponding to the axial position, passing a second excitation current signal into the first excitation coil, determining an ultrasonic wave resonance frequency according to the metal plate thickness of the to-be-detected member at the current axial position, densely scanning the circumferential region corresponding to the axial position by the electromagnetic ultrasonic multi-mode detection sensor in a point-to-point manner, and determining a debonding defect position and area according to the received ultrasonic echo signal;

[0031] S4: if there is no debonding defect in the circumferential region corresponding to the axial position, moving the electromagnetic ultrasonic multi-mode detection sensor to a next axial position of the to-be-detected member, and repeating steps S2 to S4 until the debonding quality detection of the to-be-detected member is completed.

[0032] According to a third aspect, in a possible implementation manner, the first excitation current signal and the second excitation current signal are both Barker code excitation current signals.

[0033] The application provides an electromagnetic ultrasonic multi-mode detection sensor, a device and a debonding quality detection method, wherein the first permanent magnet, the first excitation coil and the first receiving coil can constitute an electromagnetic ultrasonic resonant sensor, and the first permanent magnet, the magnetic yoke, the second permanent magnet, the second excitation coil and the second receiving coil can constitute an electromagnetic ultrasonic guided wave sensor. Therefore, the detection sensor has the advantages of single-point excitation and long-distance detection of the electromagnetic ultrasonic guided wave, and can quickly locate whether there is debonding in the circumferential area corresponding to the axial position of the measured member according to the amplitude and frequency component change of the transmission wave; meanwhile, the detection sensor has the detection advantages of the electromagnetic ultrasonic resonant transverse wave method, and can realize quantitative detection of the micro debonding defect according to the amplitude of the ultrasonic resonant energy or the frequency component of the set valve interval. The advantages of the electromagnetic ultrasonic guided wave sensor and the electromagnetic ultrasonic resonant sensor are realized by one sensor, and the electromagnetic ultrasonic guided wave can be used to quickly detect whether there is debonding, and the electromagnetic ultrasonic resonant transverse wave can be used to quantitatively detect the debonding defect, so that the high-speed and efficient detection of the debonding quality can be realized in cooperation, and the detection precision is high. In addition, the Barker code pulse compression technology is applied to the electromagnetic ultrasonic guided wave detection and the electromagnetic ultrasonic resonant transverse wave method detection during detection, so that the excitation duration can be greatly improved, the signal-to-noise ratio and the resolution of the detection echo can be improved, and the detection precision can be further improved by acquiring a higher detection echo signal-to-noise ratio in single acquisition. The effective combination and cooperation of the electromagnetic ultrasonic guided wave detection, the electromagnetic ultrasonic resonant transverse wave method detection and the Barker code pulse realize the non-contact and coupling-free rapid and efficient detection of the debonding quality, and the quantitative detection of the micro debonding defect is realized, and the detection precision is improved. The application is suitable for the rapid and efficient detection of the debonding quality of the solid rocket nozzle expansion section, and can solve the detection problems of the non-contact and the need for coupling agent of the debonding quality of the solid rocket nozzle expansion section. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only show some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0035] Figure 1 It is a structural schematic diagram of the electromagnetic ultrasonic multi-mode detection sensor provided by the embodiment of the application.

[0036] Figure 2is a schematic diagram of an electromagnetic ultrasonic multi-mode detection structure provided by an embodiment of the present application;

[0037] Figure 3 is a schematic diagram of a Barker code pulse compression principle provided by an embodiment of the present application, wherein (a) is a Barker code excitation signal, (b) is an ultrasonic echo signal, (c) is a pulse compression signal, and (d) is a pulse compression signal after sidelobe suppression;

[0038] Figure 4 is a schematic diagram of a detection mode provided by an embodiment of the present application;

[0039] Figure 5 is two result example diagrams of electromagnetic ultrasonic guided wave detection of a solid rocket nozzle divergent section provided by an embodiment of the present application, wherein (a) is a detection result example of no debonding defect, and (b) is a detection result example of having debonding defect;

[0040] Figure 6 is two result example diagrams of electromagnetic ultrasonic resonant transverse wave detection of a solid rocket nozzle divergent section provided by an embodiment of the present application, wherein (a) is a detection result example of no debonding defect, and (b) is a detection result example of having debonding defect.

[0041] In the figure, 1 is a nozzle divergent section, 2 is a rolling bearing, 3 is a first excitation coil, 4 is a copper plate, 5 is a first receiving coil, 6 is a first permanent magnet, 7 is an outer shell, 8 is a magnetic shield, 9 is a second receiving coil, 10 is a second excitation coil, 11 is a connector, 12 is a second permanent magnet, 01 is an electromagnetic ultrasonic multi-mode detection sensor, 21 is an industrial computer, 22 is a signal generator, 23 is a data acquisition card, 24 is a high-power pulse generator / receiver, 25 is a multi-channel switch, 26 is an impedance matching network, 27 is a servo motion control system, 28 is a rotating platform, and 29 is a moving platform. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0043] In the description of the present application, it needs to be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer", "center", "longitudinal", "transverse", "vertical", "horizontal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. When an element is referred to as "fixed to" another element, it can be directly on the other element or there can be a middle element. When an element is referred to as "connected" to another element, it can be directly connected to the other element or there can be a middle element.

[0044] It should be noted that in the description of the present application, the terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance or sequence. In addition, in the description of the present application, unless otherwise specified, the meaning of "a plurality of" is at least two.

[0045] Embodiment 1

[0046] The present embodiment provides an electromagnetic ultrasonic multi-mode detection sensor, as shown in Figure 1 comprising:

[0047] a housing 7;

[0048] a U-shaped permanent magnet composed of a first permanent magnet 6, a magnetic yoke 8 and a second permanent magnet 12 connected in sequence, arranged in the housing 7;

[0049] a first excitation coil 3 and a first receiving coil 5, both arranged below the first permanent magnet 6;

[0050] a second excitation coil 10 and a second receiving coil 9, both arranged directly below the U-shaped permanent magnet;

[0051] a connector 11 arranged on the housing 7, divided into two paths, one path connecting the first excitation coil 3 and the first receiving coil 5, the other path connecting the second excitation coil 10 and the second receiving coil 9.

[0052] The first permanent magnet 6, the first excitation coil 3 and the first receiving coil 5 are combined to form an electromagnetic ultrasonic resonant sensor; the first permanent magnet 6, the magnetic yoke 8 and the second permanent magnet 12 are sequentially connected to form a U-shaped permanent magnet, and then combined with the second excitation coil 10 and the second receiving coil 9 to form an electromagnetic ultrasonic guided wave sensor, and the U-shaped permanent magnet is used to provide a horizontal bias magnetic field for the second excitation coil 10 and the second receiving coil 9. The multi-mode detection sensor has two modes of electromagnetic ultrasonic guided wave detection and electromagnetic ultrasonic resonant transverse wave detection. When the debonding quality detection of the measured member 1 is performed, first, the first excitation coil 3 and the first receiving coil 5 do not work, and the second excitation coil 10 and the second receiving coil 9 work, at this time, only the excitation current signal is input into the second excitation coil 10 to generate guided waves in the measured member, realize long-distance detection, and the ultrasonic echo signal is received through the second receiving coil 9, then according to the amplitude and frequency component change, it can be quickly positioned whether there is debonding in the circumferential area corresponding to the axial position of the measured member. If there is debonding, switch to the first excitation coil 3 and the first receiving coil 5 work, and the second excitation coil 10 and the second receiving coil 9 do not work, at this time, only the excitation current signal is input into the first excitation coil 3 to generate resonant transverse waves in the measured member 1, and dense scanning is performed in the circumferential area in a point-to-point manner, and the ultrasonic echo signal is received through the first receiving coil 5, and according to the amplitude of the ultrasonic resonant energy or the frequency component of the set valve interval, the quantitative detection of the position and area size of the micro-debonding defect is realized. The sensor has the advantages of electromagnetic ultrasonic guided wave sensor and electromagnetic ultrasonic resonant sensor, and the electromagnetic ultrasonic guided wave can be used to quickly detect whether there is debonding, and the electromagnetic ultrasonic resonant transverse wave can be used to quantitatively detect the debonding defect, and the high-speed and high-efficiency detection of the debonding quality can be realized, and the detection precision is high.

[0053] In the electromagnetic ultrasonic guided wave sensor, the magnetic circuit part is composed of the first permanent magnet 6, the magnetic yoke 8 and the second permanent magnet 12, the first permanent magnet 6 and the second permanent magnet 12 are both square permanent magnets vertically magnetized, and the magnetization directions of the first permanent magnet and the second permanent magnet are opposite; the second excitation coil 10 and the second receiving coil 9 are both meander coils. By setting different combinations of the turn-to-turn distance d of the meander coil and the excitation frequency f, the excitation and reception of different modal guided waves can be realized, and the guided wave modes that can be excited include A0, S0, A1 and S1, wherein the S0 modal guided wave is most sensitive to debonding defects. The phase velocity Cphi of the S0 modal guided wave corresponding to different thicknesses of the metal plate is different, and the excitation frequency and the turn-to-turn distance of the meander coil can be calculated according to the formula Cphi = f λ = 2fd, wherein λ is the wavelength. The number of turns of the meander coil is 8-14 turns, each turn is composed of 2-6 split wires, the width of a single wire is not less than 0.15 mm, and the distance between adjacent wires is not less than 0.3 mm. In order to ensure the fitting effect of the meander coil and the curved surface to be measured such as the tail nozzle, the meander coil is made of a flexible printed circuit board. The frequency selection range is 0.5 MHz-1.0 MHz.

[0054] In the electromagnetic ultrasonic resonant sensor, the first excitation coil 3 and the first receiving coil 5 are both spiral coils or racetrack coils. As shown in Figure 1 , an example using a spiral coil is given, in order to reduce the detection blind area, the two spiral coils are arranged horizontally, and the spiral coil is made of a flexible printed circuit board. The outer diameter of the spiral coil is 3-10 mm, the width of a single wire is not less than 0.15 mm, and the distance between adjacent wires is not less than 0.3 mm. In addition, in order to avoid the generation of ultrasonic waves in the first permanent magnet 6 interfering with the ultrasonic wave signals in the to-be-measured member during the electromagnetic ultrasonic resonant transverse wave detection process, in a preferred embodiment, a thin copper plate 4 is arranged at the bottom of the first permanent magnet 6.

[0055] The connector 11 can be provided or realized by two Remo connectors as shown in Figure 1 , wherein one Remo connector connects the first excitation coil 3 and the first receiving coil 5, and the other Remo connector connects the second excitation coil 10 and the second receiving coil 9.

[0056] In order to facilitate the movement of the detection sensor, symmetrical rolling bearings 2 are arranged on the outside of the shell 7, and the shell 7 is preferably made of brass.

[0057] Example 2

[0058] The embodiment provides an electromagnetic ultrasonic multi-mode detection device, as shown in Figure 2As shown, including industrial computer 21, signal generator 22, data acquisition card 23, high-power pulse generator / receiver 24, multiplexer 25, impedance matching network 26 and electromagnetic ultrasonic multi-mode detection sensor 01 as described in embodiment 1;

[0059] The industrial computer 21 is connected with the signal generator 22, data acquisition card 23, the signal generator 22, data acquisition card 23 are connected with the high-power pulse generator / receiver 24, the high-power pulse generator / receiver 24, multiplexer 25, impedance matching network 26, electromagnetic ultrasonic multi-mode detection sensor 01 are connected in turn.

[0060] The multiplexer 25 is used to select access the first excitation coil 3 and the first receiving coil 5 or select access the second excitation coil 10 and the second receiving coil 9. Thus a set of control system realizes time-sharing excitation and receiving of electromagnetic ultrasonic resonant sensor and electromagnetic ultrasonic guided wave sensor two kinds of sensors, that is, a set of equipment has the functions of guided wave detection and resonant transverse wave detection at the same time, effectively reduces the equipment size and cost, and improves the detection efficiency. The industrial computer 21 is connected with the high-power pulse generator / receiver 24 through the signal generator 22, which is used to control the amplitude, frequency, duration and waveform of the excitation current input to the first excitation coil 3 or the second excitation coil 10, and also can control the filter bandwidth and gain multiple of weak signal; The industrial computer 21 is connected with the high-power pulse generator / receiver 24 through the data acquisition card 23, which is used to realize the digital-to-analog conversion of ultrasonic echo signal.

[0061] When working, the second excitation coil 10 and the second receiving coil 9 are controlled to access first, at this time the electromagnetic ultrasonic guided wave sensor works, which is used for exciting and receiving guided wave in the circumferential direction of the measured member, and is used for rapid detection of debonding defects in the axial position of the circumferential area of the measured member at the current measuring point. If it is determined that there is debonding in the circumferential area of the axial position, the first excitation coil 3 and the first receiving coil 5 are controlled to access, at this time the electromagnetic ultrasonic resonant sensor works, which is used for intensive scanning in the circumferential area in a point-to-point manner, and realizes quantitative detection of the position and area size of small debonding defects. In the device, the high-power pulse generator / receiver 24 is mainly used for providing high-power transient current excitation for the multi-mode detection sensor, and realizing narrow-band filtering and high-gain amplification of weak ultrasonic echo signal. The impedance matching network 26 is used for matching the equivalent impedance of the multi-mode detection sensor and the output / input impedance of the high-power pulse generator / receiver, realizing maximization of energy transmission, and improving the transduction efficiency of the multi-mode detection sensor.

[0062] It should be noted that in order to further improve the detection accuracy, in a preferred embodiment, the Barker code pulse compression technology is introduced, that is, the excitation current signal input into the first excitation coil 3 or the second excitation coil 10 is a Barker code excitation current signal, and the Barker code excitation current signal is generated by a signal generator and a high-power generator / receiver combination. Its principle is as shown in Figure 3 Figure 3 (a) is a Barker code excitation current signal, and when the pulse compression technology is used, the excitation current is loaded on the multi-mode detection sensor in the form of a Barker code excitation current signal. Figure 3 (b) is an open-circuit induced voltage signal received by the multi-mode detection sensor. When Figure 3 (a) signal and Figure 3 (b) signal are convolved, a pulse compression signal as shown in Figure 3 (c) can be obtained, and after delay superposition and sidelobe suppression, a pulse compression signal as shown in Figure 3 (d) can be obtained. Figure 3 (d) and Figure 3 (c) compared, the signal-to-noise ratio and resolution are significantly improved, which is beneficial to improve the detection accuracy.

[0063] For the application scene of detecting the debonding mass of the solid rocket nozzle expansion section, the detection device further comprises a servo motion control system 27 and a rotating platform 28 and a moving platform 29 connected thereto; the servo motion control system 27 is connected with the industrial computer 21; and the electromagnetic ultrasonic multi-mode detection sensor 01 is installed on the moving platform 29.

[0064] Taking the solid rocket nozzle expansion section as an example, the to-be-detected member is placed on the rotating platform 28, the industrial computer 21 controls the moving platform 29 to move up and down through the servo motion control system 27, controls the multi-mode detection sensor 01 to move to a certain axial position, and realizes debonding defect detection of the circumferential area corresponding to the axial position by using the electromagnetic ultrasonic guided wave sensor; when a debonding defect is detected, the industrial computer 21 controls the rotating platform 28 to rotate through the servo motion control system 27, and at this time, dense scanning in the circumferential area corresponding to the axial position is realized by using the electromagnetic ultrasonic resonant sensor to determine the defect position and size; when there is no defect in the circumferential area corresponding to the axial position, the industrial computer 21 controls the moving platform 29 to move through the servo motion control system 27, so that the multi-mode detection sensor moves to the next axial position, and then the above process is repeated until the detection of the to-be-detected member is completed.

[0065] ​The mobile platform 29 comprises a mobile base, a sliding support rod and a spring assembly. One end of the sliding support rod is slidably installed on the mobile base, and the other end is rotatably connected with the electromagnetic ultrasonic multi-mode detection sensor. One end of the spring assembly is connected with the mobile base, and the other end is connected with the electromagnetic ultrasonic multi-mode detection sensor. The sliding support rod is telescopic and slidable, and is used for supporting the multi-mode detection sensor. The spring assembly comprises at least two springs located above and below the sliding support rod. The spring assembly provides elastic force, so that the multi-mode detection sensor can rotate according to the surface condition of the measured member, and the multi-mode detection sensor can be tightly attached to the surface of the measured member. The rotating platform 28 can be realized by a motor and a platform arranged at the output end of the motor.

[0066] Embodiment 3

[0067] The embodiment provides a debonding quality detection method, which comprises the following steps:

[0068] S1: moving the electromagnetic ultrasonic multi-mode detection sensor as described in embodiment 1 to an axial position of the measured member;

[0069] S2: passing a first excitation current signal into the second excitation coil to make the measured member generate ultrasonic guided waves propagating along the circumferential direction corresponding to the axial position, receiving an ultrasonic echo signal, and determining whether there is a debonding defect in the circumferential region corresponding to the axial position;

[0070] S3: if there is a debonding defect in the circumferential region corresponding to the axial position, passing a second excitation current signal into the first excitation coil, determining an ultrasonic wave resonance frequency according to the metal plate thickness of the measured member at the current axial position, densely scanning the circumferential region corresponding to the axial position by the electromagnetic ultrasonic multi-mode detection sensor in a point-to-point manner, and determining the debonding defect position and area according to the received ultrasonic echo signal;

[0071] S4: if there is no debonding defect in the circumferential region corresponding to the axial position, moving the electromagnetic ultrasonic multi-mode detection sensor to the next axial position of the measured member, and repeating steps S2 to S4 until the debonding quality detection of the measured member is completed.

[0072] In order to improve the detection accuracy, the first excitation current signal and the second excitation current signal are preferably Barker code excitation current signals in the embodiment.

[0073] The following will be described in detail taking the solid rocket tail nozzle expansion section as an example.

[0074] The detection device provided in embodiment 2 is used for detection. The tail nozzle expansion section is placed on the rotating platform, and the specific detection process comprises the following steps:

[0075] Step 1: control the mobile platform to carry the electromagnetic ultrasonic guided wave sensor (one of the working modes of the multi-mode detection sensor) to a certain axial position of the nozzle expansion section, the signal generator generates a Barker code excitation current signal through the high-power pulse generator / receiver, which acts on the electromagnetic ultrasonic guided wave sensor to generate ultrasonic guided waves of specific or several modal components, the ultrasonic guided waves propagate along the corresponding circumferential direction of the axial position, and a single implementation realizes the debonding defect detection of the axial position and the circumferential area. By pulse compression and sidelobe suppression of the ultrasonic guided wave signal and the Barker code excitation current signal, the pulse compression signal of the transmission wave can be obtained. According to the amplitude and frequency component change of the pulse compression signal, whether there is a debonding defect in the circumferential area of the axial position is analyzed.

[0076] Step 2: if there is a debonding defect in the circumferential area of the axial position, the high-power pulse generator / receiver is connected to the electromagnetic ultrasonic resonant sensor (another working mode of the multi-mode detection sensor) through the multi-channel switch; the signal generator generates a Barker code excitation current signal through the high-power pulse generator / receiver, which acts on the electromagnetic resonant transverse wave sensor; the ultrasonic resonant frequency is determined according to the metal plate thickness of the current position of the nozzle expansion section; the rotating platform drives the nozzle to rotate circumferentially, and the electromagnetic ultrasonic resonant sensor adopts a point-to-point mode to densely scan the circumferential area, and the size of the debonding defect area is determined according to the amplitude of the ultrasonic resonant energy or frequency component of the set valve interval.

[0077] Step 3: if there is no debonding defect in the circumferential area of the axial position, the electromagnetic ultrasonic guided wave sensor carried by the mobile platform reaches the next axial position, and steps 1-3 are repeated.

[0078] For the convenience of understanding, it is illustrated by taking Figure 4 as an example. First, the electromagnetic ultrasonic guided wave sensor reaches Figure 4 -① area, emits ultrasonic guided waves along the circumferential direction, and if Figure 4 -① area has no debonding defect, the electromagnetic ultrasonic guided wave sensor carried by the mobile platform directly reaches Figure 4 -② area. If Figure 4 -② area has no debonding defect, the electromagnetic ultrasonic guided wave sensor carried by the mobile platform directly reaches Figure 4 -③ area. Figure 4 If Figure 4 -③ area has a debonding defect, as shown in -③ area, the high-power pulse generator / receiver is connected to the electromagnetic ultrasonic resonant sensor through the multi-channel switch, the rotating platform drives the nozzle to rotate circumferentially, and the electromagnetic ultrasonic resonant transverse wave sensor adopts a point-to-point mode to densely scan the circumferential area to determine the debonding defect position and area size.

[0079] Generally, the metal layer of the nozzle extension is aluminum, titanium and carbon steel, so the electromagnetic ultrasonic sensor is based on the Lorentz force mechanism in aluminum and titanium, and mainly based on the Lorentz force and magnetostrictive two transduction mechanisms in carbon steel.

[0080] When the Barker code pulse compression is used, 13-bit Barker code can be used preferentially, and the sequence is [1, 1, 1, 1, 1-1, -1, 1, 1, -1, 1, -1, 1], and the sine pulse train is used as the symbol of the Barker code signal. The received ultrasonic echo signal is pulse-compressed with the Barker code excitation current signal, and the pulse compression signal can be obtained, but the main side lobe ratio increases obviously, and the side lobes are uniformly and symmetrically distributed around the main lobe. After a certain number of time delays, the pulse compression signal is multiplied by the corresponding weighting coefficient, and then all the weighted outputs are added, so as to suppress the side lobes. Through the Baker code pulse compression, the signal with small amplitude and long duration can be compressed into a signal with large amplitude and short duration, so as to enhance the signal-to-noise ratio and the resolution. In the debonding defect discrimination aspect, for the electromagnetic ultrasonic guided wave detection, whether the debonding defect exists can be determined according to the amplitude and frequency component change of the pulse compression signal of the transmission wave; for the electromagnetic ultrasonic resonant transverse wave detection, the size of the debonding defect area can be determined according to the amplitude of the ultrasonic resonant energy or the frequency component in the set valve interval.

[0081] Figure 5 Fig. 1 shows two result example diagrams of the solid rocket nozzle extension electromagnetic ultrasonic guided wave detection provided by the embodiment of the present application, the excitation frequency is 1.041 MHz S0 guided wave mode, the number of turns of the meander coil is 12 turns, the turn spacing is 1.565 mm, each turn is composed of four split wires, the width of each wire is 0.15 mm, and the spacing between adjacent wires is 0.3 mm. The length, width and height of the square permanent magnet are 40 mm x 25 mm x 10 mm respectively. Among them Figure 5 (a) is the pulse compression signal after side lobe suppression without debonding defect, Figure 5 (b) is the pulse compression signal after side lobe suppression with debonding defect.

[0082] Figure 6 Fig. 2 shows two result example diagrams of the solid rocket nozzle extension electromagnetic ultrasonic resonant transverse wave detection provided by the embodiment of the present application, the excitation frequency is 2.1 MHz transverse wave, the spiral coil adopts a plurality of sandbag wires with a diameter of 0.25 mm, the wire diameter is 0.05 mm, and the coil diameter is 10 mm. Among them Figure 6 (a) is the pulse compression signal after side lobe suppression without debonding defect, Figure 6 (b) is the pulse compression signal after side lobe suppression with debonding defect.

[0083] It can be understood that the same or similar parts in the above-mentioned embodiments can be mutually referenced, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0084] Although the embodiments of the present application have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the present application, and the ordinary skilled in the art can make changes, modifications, replacements and variations to the above-mentioned embodiments within the scope of the present application.

Claims

1. An electromagnetic ultrasonic multi-mode detection sensor, characterized in that, include: shell; A U-shaped permanent magnet, consisting of a first permanent magnet, a yoke, and a second permanent magnet connected in sequence, is disposed inside the outer shell; The first excitation coil and the first receiving coil are both located below the first permanent magnet, and the first excitation coil and the first receiving coil are arranged side by side in a direction parallel to the lower surface of the first permanent magnet. The second excitation coil and the second receiving coil are both located directly below the U-shaped permanent magnet and are stacked in a direction perpendicular to the lower surface of the first permanent magnet. A connector is provided on the housing and is divided into two paths: one path connects the first excitation coil and the first receiving coil, and the other path connects the second excitation coil and the second receiving coil.

2. The electromagnetic ultrasonic multi-modal detection sensor of claim 1, wherein, A copper plate is provided at the bottom of the first permanent magnet.

3. The electromagnetic ultrasonic multi-modal detection sensor of claim 1, wherein, The first excitation coil and the first receiving coil are helical coils or runway coils.

4. The electromagnetic ultrasonic multi-modal detection sensor of claim 1, wherein, Both the second excitation coil and the second receiving coil are zigzag coils.

5. The electromagnetic ultrasonic multi-mode detection sensor according to any one of claims 1 to 4, characterized in that, The first excitation coil, the first receiving coil, the second excitation coil, and the second receiving coil are all made of a flexible hard brush circuit board.

6. An electromagnetic acoustic multi-mode detection device, characterized in that, Includes an industrial control computer, a signal generator, a data acquisition card, a high-power pulse generator / receiver, a multiplexer, an impedance matching network, and an electromagnetic ultrasonic multimode detection sensor as described in any one of claims 1 to 5; The industrial control computer is connected to the signal generator and the data acquisition card. The signal generator and the data acquisition card are both connected to the high-power pulse generator / receiver. The high-power pulse generator / receiver, the multiplexer, the impedance matching network, and the electromagnetic ultrasonic multi-mode detection sensor are connected in sequence.

7. The electromagnetic ultrasonic multi-modal detection apparatus of claim 6, wherein, It also includes a servo motion control system and a rotating platform and a moving platform connected thereto; the servo motion control system is connected to the industrial control computer; the electromagnetic ultrasonic multi-mode detection sensor is mounted on the moving platform.

8. The electromagnetic ultrasonic multi-modal detection apparatus of claim 7, wherein, The mobile platform includes a mobile base, a sliding support rod, and a spring assembly. One end of the sliding support rod is slidably mounted on the mobile base, and the other end is rotatably connected to the electromagnetic ultrasonic multi-mode detection sensor. One end of the spring assembly is connected to the mobile base, and the other end is connected to the electromagnetic ultrasonic multi-mode detection sensor.

9. A debonded mass detection method characterized by, include: S1: Move the electromagnetic ultrasonic multi-mode detection sensor as described in any one of claims 1 to 5 to an axial position of the test piece; S2: A first excitation current signal is passed into the second excitation coil to make the test piece generate an ultrasonic guided wave that propagates along the circumferential direction corresponding to the axial position, and the ultrasonic echo signal is received to determine whether there is a debonding defect in the circumferential region corresponding to the axial position. S3: If there is a debonding defect in the circumferential region corresponding to the axial position, a second excitation current signal is passed into the first excitation coil; the electromagnetic ultrasonic multi-mode detection sensor performs a point-to-point dense scan of the circumferential region corresponding to the axial position, and determines the location and area of ​​the debonding defect based on the received ultrasonic echo signal. S4: If there is no debonding defect in the circumferential area corresponding to the axial position, move the electromagnetic ultrasonic multi-mode detection sensor to the next axial position of the test piece and repeat steps S2 to S4 until the debonding quality detection of the test piece is completed.

10. The debonding quality detection method according to claim 9, wherein The first excitation current signal and the second excitation current signal are both Barker code excitation current signals.

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