275 results about "Laser ultrasonics" patented technology

The invention discloses a mechanical arm welding detection intelligent diagnosis method and system based on laser ultrasonic guided waves. According to the system, a high-precision multi-degree-of-freedom steering engine, an infrared distance measurement array, a temperature sensor, a laser vibration exciter and a laser vibration meter are integrated at the tail end of a mechanical arm, synchronous operation of welding and online detection is achieved by presetting a welding track, and the system collects an excitation signal, a reflection ultrasonic signal and temperature data through a high-speed data collection card; and the signal is preprocessed through a temperature matching model, phase compensation and baseline correction. Then, wavelet decomposition is adopted to extract time-frequency features, intelligent diagnosis is achieved through a pre-trained one-dimensional convolutional neural network, a dynamic threshold value is set based on the 3 sigma criterion, and recheck feedback is automatically triggered when detection data exceed the limit, the welding detection efficiency and precision are remarkably improved through the scheme, data closed-loop management and intelligent quality tracing are achieved, and the reliability of welding detection is improved. And the automatic production requirement of modern steel structure manufacturing is met.

The invention relates to the technical field of performance detection, and discloses a blade structure performance detection device and method, and the method comprises the steps: carrying out the laser ultrasonic scanning of a titanium alloy engine blade, and obtaining multi-mode spectrum feature data; performing parameter inversion and iterative optimization calculation according to the multi-modal spectrum characteristic data to obtain material parameter distribution data of a local area of the blade; performing annular scanning analysis on the titanium alloy engine blade based on the material parameter distribution data to obtain local structure feature data; performing modal decomposition on the local structure feature data to obtain fatigue damage accumulation data; and inputting the accumulated fatigue damage data into a dual decoupling diagnosis model for comparative learning and antagonistic feature separation to obtain a target diagnosis result, the method overcomes the limitation of a traditional linear superposition method, accurately predicts the fatigue damage evolution law under a complex load, effectively solves the problem of working condition interference, and improves the diagnosis accuracy. And the robustness and generalization of fault diagnosis are enhanced.

The invention discloses a boiler inner wall crack detection method based on a laser ultrasonic wave and infrared thermal imaging technology. The method comprises the following steps: checking detection equipment; cleaning the inner wall of the boiler; performing preliminary visual inspection on the inner wall of the boiler; laser ultrasonic detection equipment is arranged on the inner wall of the boiler; systematically performing laser ultrasonic scanning on the inner wall of the boiler; an infrared thermal imaging camera is used for scanning the inner wall of the boiler; performing infrared thermal imaging scanning; comparing and analyzing the data; and compiling a detailed detection report. According to the invention, the laser ultrasonic detection technology can detect deep micro cracks on the inner wall of the boiler with high precision, even the micro cracks can be found before the micro cracks become significant problems, and the infrared thermal imaging technology can provide visual information about crack positions and sizes by capturing thermogram differences of crack areas, so that the accuracy of the thermal imaging is improved. This technique is particularly suited for the discovery of surface cracks and for the assessment of the scope of crack impact.

The invention relates to a near-surface defect positioning method based on a laser ultrasonic surface wave, which comprises the following steps of: extracting a defect tiny inverse signal and calculating reflection time delay by utilizing a high-frequency surface wave signal excited by laser through a wavenumber domain method to determine a defect position, and determining the burial depth of the defect through a reflection wave amplitude value of the defect; comprising the steps of S1, laser ultrasonic finite element simulation; s2, acquiring high-frequency laser ultrasonic signals; s3, direct wave and reflected wave extraction and time delay calculation; s4, determining defect space coordinates; and S5, determining the burial depth of the defect. The method makes full use of the advantages of high frequency and long propagation distance of surface waves, can effectively solve the problem of defect detection and positioning of the tested piece, can quickly detect the submillimeter defects, is high in positioning precision, and is suitable for positioning and detecting the submillimeter defects on the near surface of a structure.

The invention discloses a detection method and device for intelligent visual detection of parts and a storage medium, belongs to the technical field of industrial quality detection, and aims to solve the problems that surface and internal defects of complex parts are difficult to identify synchronously and the identification precision is low. The method comprises the following steps: acquiring multi-modal image data obtained through structured light three-dimensional imaging and laser ultrasonic scanning; performing geometric registration and scale normalization on the image to generate a fused image; carrying out image preprocessing and edge analysis, and extracting a region of interest; dividing the candidate region of interest into a plurality of image blocks, and inputting the image blocks into an anomaly detection network; calculating a reconstruction error between the original image block and the reconstructed image block, and generating an abnormal scoring graph; and finally, extracting a defect area through image post-processing, and outputting information such as a defect type, a spatial position, a geometric dimension and a severity level. According to the method, the robustness and accuracy of multi-modal defect identification are improved, and the method is suitable for an online visual inspection task of an industrial production line.

The invention discloses a laser ultrasonic defect imaging method based on sampling-imaging double-order compressed sensing, and relates to the technical field of laser ultrasonic detection and material defect detection, and the method comprises the following steps: carrying out sparse scanning on a to-be-detected sample through a random sparse sampling strategy; according to a compressed sensing principle, global ultrasonic intensity distribution of full-matrix scanning under a high sampling rate is reconstructed, and global sparse positioning is realized through extreme value detection; then, on the basis of global sparse positioning, carrying out local fine scanning by adopting high spatial resolution; and generating a sparse imaging result with low spatial resolution by using global sparse positioning and local fine scanning data through a synthetic aperture focusing technology, and performing high-resolution compressed sensing reconstruction imaging by using a compressed sensing principle again. Therefore, by adopting the laser ultrasonic defect imaging method based on sampling-imaging double-order compressed sensing, efficient imaging of tiny defects can be realized, and scanning points are reduced while the imaging precision is improved.

The invention relates to the technical field of laser processing, in particular to multi-axis ultrafast laser and ultrasonic combined processing equipment. The five-axis linkage machining equipment is used for simultaneously or independently moving in five different axial directions of an X axis, a Y axis, a Z axis, an A axis and a B axis, and a workpiece to be machined is clamped on the workbench; the laser generator is mounted on a cross beam of the five-axis linkage processing equipment; the ultrasonic vibration main shaft is mounted on a Z-axis mounting seat in the five-axis linkage machining equipment; the four-axis small motion platform is mounted on a Z-axis mounting seat in the five-axis linkage machining equipment and is used for accurately adjusting the spatial position of the galvanometer and the rotating angle of a laser beam, so that the four-axis small motion platform and the ultrasonic vibration main shaft cutter form combined machining with different laser incident angles; the three-dimensional scanner is used for obtaining the six-degree-of-freedom point cloud model of the workpiece to be machined. A three-dimensional scanner, a galvanometer and an ultrasonic vibration main shaft are integrated in five-axis linkage machining equipment, so that the equipment compactness and the operation convenience are improved; therefore, the ultra-fast laser is suitable for hard light path transmission.

The invention relates to the technical field of ultrasonic signal processing, in particular to a wavelet and MAD adaptive threshold combined laser ultrasonic signal denoising method. The method comprises the following steps: firstly, preprocessing an acquired trigger channel signal and an ultrasonic channel signal, determining a signal starting point through differential positioning, and intercepting an effective signal segment; carrying out multilayer wavelet decomposition on the effective signal segment to obtain a wavelet coefficient of each layer; extracting a detail coefficient of the highest decomposition layer, and adaptively estimating a noise standard deviation based on a median absolute deviation criterion; calculating an adaptive threshold according to the noise standard deviation and the signal length, and processing each layer of wavelet coefficient by adopting a hard threshold function; and finally, carrying out wavelet inverse transformation reconstruction to obtain a denoised signal. According to the method, prior noise information is not needed, the noise level can be adaptively estimated, the optimal threshold value can be determined, the signal features are reserved while noise is effectively suppressed, and the signal-to-noise ratio is remarkably improved.

The invention discloses a crystallinity detection method and related equipment, and relates to the technical field related to crystallinity, the crystallinity detection method comprises the following steps: determining related parameters of laser ultrasonic detection equipment, and the laser ultrasonic detection equipment is used for detecting the crystallinity of a to-be-detected polymer; laser is emitted to the current detection position of the to-be-detected polymer according to the related parameters, an original ultrasonic signal corresponding to the current detection position is determined, and the original ultrasonic signal carries intrinsic information of the to-be-detected polymer; and based on the original ultrasonic signal and each ultrasonic detection parameter, determining fused effective data, and based on the fused effective data, determining the crystallinity of the polymer. According to the invention, on-line accurate detection of the crystallinity of the polymer is realized.

The invention discloses a subsurface defect multi-mode laser ultrasonic C scanning image reconstruction method. The method comprises the following steps: carrying out two-dimensional scanning on a detected object by utilizing a laser ultrasonic detection device to obtain a multi-mode ultrasonic A scanning time domain signal data set; converting the data set into a frequency domain signal, and performing position coding according to the acquisition position of the signal; splicing the frequency domain signals with the position codes, and calculating the similarity between the signals; according to the calculated signal similarity, selecting a set number of signals to construct a graph data set; and inputting the graph data set into a trained graph neural network model to obtain a classification result of the defect signal at each position, judging whether the classification result is from a defect area or not, and performing C scanning image reconstruction according to the original acquisition position of each A scanning signal and the classification result. According to the invention, high-resolution scanning imaging of the subsurface defect can be realized, and the accuracy and reliability of subsurface defect detection are obviously improved.

The utility model provides a four-roll-shaft laser ultrasonic concrete paver, which relates to the technical field of concrete pavers and comprises a laser ultrasonic concrete paver assembly, and a cleaning assembly is arranged in the laser ultrasonic concrete paver assembly. A tamping and paving assembly is arranged on the side face of the laser ultrasonic concrete paver assembly, the laser ultrasonic concrete paver assembly comprises an auger material distribution shaft, a high-speed leveling shaft and a high-frequency vibration shaft, and the tamping and paving assembly comprises a fixing plate; according to the concrete surface rubbing device, the vibration motor works to drive the vibration rubbing plate to vibrate, so that the vibration rubbing plate vibrates and rubs the concrete surface, and tiny low-lying and uneven areas on the concrete surface can be conveniently filled; the undulation and wavy defects caused by insufficient extrusion of the roller shaft in the paving process of the concrete surface are effectively reduced, so that the concrete surface is smoother, the flatness and compactness of the concrete surface are improved, and the pavement quality is further improved.

The invention discloses a frequency domain laser ultrasonic defect detection method and system for a bonding structure material, and relates to the technical field of defect detection, and the method comprises the following steps: generating a modulation signal according to a simple harmonic waveform and a resonant frequency corresponding to a to-be-detected bonding structure material, and sending modulation laser to a preset excitation point on the surface of the to-be-detected bonding structure material according to the modulation signal; emitting incident detection laser to an excitation point to detect an ultrasonic signal excited by the modulation laser, and determining a reflection detection laser electric signal; determining the amplitude or phase of the excitation point relative to the ultrasonic signal based on the reflection detection laser electric signal; and carrying out moving defect detection on the to-be-detected bonding structure material, and determining a defect detection result by adopting the amplitudes or phases of the plurality of excitation points. Based on the scheme, the photo-thermal-acoustic effect detection mode based on the modulated laser is beneficial to improving the reliability of laser ultrasonic defect detection of the bonding structure material.

The invention discloses a heterostructure bonding quality evaluation method and device based on non-contact laser ultrasound. The method comprises the following steps: aiming at a target multi-layer heterostructure, calculating all corresponding resonance modes by utilizing a computer finite element simulation method to obtain a multi-mode theoretical resonance frequency; carrying out laser ultrasonic multi-point scanning on a preset plane area of the target multilayer heterostructure based on a thermoelastic effect by utilizing the established detection device, and collecting an ultrasonic signal; performing time-frequency domain conversion on the ultrasonic signal to obtain a corresponding frequency spectrum signal, and further obtaining a multi-modal measurement resonance frequency; and comparing the multi-mode theoretical resonance frequency with the multi-mode measurement resonance frequency to obtain a heterostructure bonding quality evaluation result. According to the invention, the accuracy of bonding quality evaluation is improved, and the evaluation convenience is improved.

The invention provides a titanium alloy surface laser ultrasonic composite cleaning reinforced welding method, belongs to the technical field of non-ferrous metal surface cleaning and modification, and aims to solve the problems of poor welding seam quality and poor surface corrosion resistance, fatigue resistance and the like in the titanium alloy welding process. The cleanliness of the surfaces of components, welding grooves and the like is improved, and the production and machining efficiency is improved. In the fusion welding process, ultrasonic excitation of a high-energy beam is applied to the back face of a weld joint, the grain size of the weld joint is refined, the mechanical property of a connector is improved, rotating ultrasonic waves are applied to the surface of a component and the weld joint, the component and the surface of the weld joint generate plastic deformation, and the overall performance of the component and the surface of the weld joint is improved. The high temperature resistance, the corrosion resistance, the fatigue resistance and the like are improved.

The invention discloses a cable strength detection method and system, relates to the technical field of cable detection, and solves the technical problems that the metal cable detection process is not standard, the defect positioning and quantification precision is low, the contradiction between the non-metal cable detection efficiency and precision is prominent, and microscopic verification is lacked. A high-frequency arc-shaped phased array probe, a bicrystal oblique TOFD probe and an oil-based high-viscosity coupling agent are adopted, a layered focusing technology is combined, laser ultrasonic non-contact detection and ultrasonic microscope high-resolution imaging are adopted for a non-metal cable, and spiral scanning and circumferential fixed-point scanning are combined, so that the defect omission ratio in the circumferential direction is reduced; the abnormal region judgment takes a calibration test block as a reference, the misjudgment rate is reduced, the authenticity is verified through coarse scanning and locking of a core region, fine scanning and acquisition of a high-resolution image and multi-angle imaging, the defect type judgment basis is clear, and the misjudgment rate is reduced.

The invention provides an argon arc welding tungsten electrode appearance defect detection method and system and a storage medium, and relates to the technical field of tungsten electrode appearance detection.The method comprises the steps that firstly, a sample electrode with known defects is subjected to three-dimensional scanning and discretization into a plurality of space points, and each point is endowed with a defect existence mark; by applying a composite sine wave excitation current, an eddy current signal generated when a collector spirally passes through a detection coil at a constant speed is acquired, and laser ultrasonic scanning is synchronously utilized to acquire full-matrix data and reconstruct a three-dimensional gray model. And constructing a double-branch deep learning model, fusing the eddy current feature vector and the ultrasonic image block feature, and learning a mapping relationship between the eddy current feature vector and the defect mark. And performing the same detection on a to-be-detected electrode, outputting the defect confidence of each position by using the trained model, calculating a comprehensive quality index in combination with a preset defect severity weight and a spatial key region weight, and judging whether the electrode is qualified or not according to a qualified threshold value. According to the invention, high-precision, automatic and comprehensive detection of surface and internal defects is realized.

The invention discloses a component defect detection method and device, electronic equipment and a storage medium. The method comprises the following steps: constructing a three-dimensional model of a component; collecting laser ultrasonic data of the three-dimensional model, and collecting a thermal imaging image and a polarized light image of the assembly; based on the laser ultrasonic data, the thermal imaging image and the polarized light image, predicting to obtain a first defect category and a first defect position corresponding to a defect area of the assembly; based on the defect category and the defect position of the defect area, reconstructing three-dimensional defect data of the component; and on the basis of the three-dimensional defect data, predicting to obtain an expansion direction and an expansion range of the defect area.

The invention discloses an automatic grading device for thermal shock cracks of a coating and an application method. Comprising a terahertz wave detection module, a laser ultrasonic excitation and detection module, a high-precision three-dimensional motion control platform, a multi-mode signal synchronous acquisition and processing unit, a crack intelligent grading evaluation unit, an environment simulation and temperature control unit, a protective shell and a human-computer interaction interface. The near-surface dielectric property change of the coating is represented through the terahertz technology, the deep mechanical property evolution is detected through the laser ultrasonic technology, the thermal shock service condition is reproduced in combination with a high-temperature environment simulation unit, and a multi-modal feature fusion algorithm and a physical model and machine learning collaborative inversion model are adopted to obtain the thermal shock resistance of the coating. And automatic quantitative evaluation and severity grading of the depth, density, length and network connectivity of the thermal shock cracks of the thermal barrier coating are realized. The problems that an existing single detection method is insensitive to vertical cracks, poor in high-temperature environment adaptability and low in manual evaluation efficiency are solved.

The invention discloses an in-situ nondestructive measurement method, medium and equipment for elastic parameters of a multi-thin-layer heterogeneous material, and belongs to the technical field of ultrasonic measurement. The method comprises the steps that a multi-mode ultrasonic propagation multi-parameter model is established for a to-be-measured structure, a propagation time theoretical value corresponding to each ultrasonic mode is calculated, and the to-be-measured structure is a multi-thin-layer heterostructure; laser ultrasonic linear scanning is carried out on the to-be-detected structure, ultrasonic signals of all ultrasonic modes propagating in different directions are collected, and a line scanning ultrasonic data set is obtained; for a selected ultrasonic mode, extracting propagation time experimental values under different excitation-receiving point combinations from ultrasonic signals of the line scanning ultrasonic data set; and aiming at the selected ultrasonic mode, minimizing the difference between the propagation time theoretical value and the propagation time experimental value as a target function, and using a parameter optimization algorithm to invert the elastic parameter of the to-be-tested structure. According to the invention, long-distance and non-contact in-situ nondestructive measurement can be realized, and the operation is simple.

The invention discloses a beat frequency coding type multi-wavelength optical fiber laser ultrasonic detection positioning system, which comprises an optical pumping device, an optical acquisition device, a signal demodulation device and an optical fiber laser ultrasonic sensing array, and is characterized in that the optical fiber laser ultrasonic sensing array comprises at least three dual-polarization optical fiber lasers which are not distributed on the same straight line; and the dual-polarization fiber lasers are used for generating at least three paths of single-frequency dual-polarization laser under the excitation of the pump light, and each dual-polarization fiber laser has different beat frequencies and output wavelengths. The ultrasonic detection positioning system modulates and demodulates the frequency of each laser polarization beat frequency signal based on an ultrasonic signal, is high in sensitivity, does not need extra time division and wavelength division multiplexing modules, and greatly reduces the complexity of the system. The invention further discloses a demodulation method of the ultrasonic detection positioning system.

The invention provides a long-term service metal grain size identification method based on machine learning. The method comprises the following steps: exciting the surface of a test piece to generate ultrasonic waves; acquiring ultrasonic information generated by exciting the test piece, and inputting the ultrasonic information into a sample database for feature comparison; predicting the grain size according to the prediction model, and calculating an error according to the grain size pair of the tested piece; evaluating the safety of the long-term service metal of the test piece according to the grain size error of the test piece and the grain size predicted by the prediction model, and outputting a detection result; the ultrasonic information generated by exciting the test piece is subjected to data storage for enriching a sample database, and a machine learning algorithm can learn and construct a more complete data model. During use, a laser ultrasonic technology and a non-contact detection mode are adopted, the surface of a test piece does not need to be damaged, damage to a main steam main pipe is avoided, meanwhile, shutdown is not needed, and the detection cost and time are remarkably reduced.

The invention relates to the field of welding seam detection, and discloses a welding seam center line real-time tracking method and device, computer equipment and a storage medium, and the method comprises the steps: obtaining a laser tracking evaluation speed, an ultrasonic tracking evaluation speed and a tracking speed threshold value of a to-be-detected weldment; if the laser tracking evaluation speed and the ultrasonic tracking evaluation speed are both larger than the tracking speed threshold value, the weld joint center line of the to-be-detected weldment is tracked according to a laser and ultrasonic simultaneous inspection strategy; and if the laser tracking evaluation speed or the ultrasonic tracking evaluation speed is smaller than or equal to the tracking speed threshold value, the welding seam center line of the to-be-detected weldment is tracked according to a main laser and auxiliary ultrasonic strategy. According to the invention, the obvious limitation of a single laser tracking technology under the conditions of a complex surface and strong illumination is overcome, and high-precision and high-robustness real-time tracking is realized through acousto-optic fusion.

A catheter-implemented transducer device for intravascular thrombolysis, is described herein. Such a transducer device includes a catheter defining a longitudinal axis and having opposed proximal and distal ends. At least one ultrasonic transducer arrangement is disposed about the distal end. The ultrasonic transducer arrangement is oriented with acoustic waves propagating parallel or perpendicular to the longitudinal axis. Optionally, the ultrasonic transducer arrangement is configured as a multi-layer stacked structure of ultrasonic transducer elements. Optionally, the ultrasonic transducer arrangement is a laser ultrasonic transducer arrangement. Optionally, the ultrasonic transducer arrangement is configured to operate in a lateral mode.

The invention belongs to the technical field of laser cladding, and particularly relates to a cladding quality visualization method and system integrating an infrared thermal imaging technology and a laser ultrasonic technology, and the method comprises the steps: constructing a molten pool quality monitoring system integrating the infrared thermal imaging technology and the laser ultrasonic technology; the infrared thermal imaging module is used for measuring the temperature of the surface of the molten pool in real time to obtain a temperature distribution image of the surface of the molten pool; through an image processing technology, a temperature signal is extracted and is used as a feedback signal for controlling parameters such as laser power; the laser ultrasonic module emits laser pulses to the cooled cladding layer to excite ultrasonic waves; when ultrasonic waves are propagated in a cladding layer and encounter internal defects, the phenomena of reflection, scattering and the like can occur; the reflected ultrasonic signals are received and analyzed to obtain defect information in the molten pool; and the data processing and visualization module carries out fusion processing on the temperature information and the defect information to generate a comprehensive visualization image of the quality of the molten pool. The advantages of the two technologies are combined, real-time monitoring and visualization of the surface temperature and the internal quality of the molten pool are achieved, and the control precision of the cladding process and the product quality are improved.

The invention discloses a laser ultrasonic dual-system paver which comprises a truss formed by splicing a plurality of truss sections; cantilever trusses are fixedly arranged at two ends of the top surface of the truss, and a paving device is arranged at the bottom; the two walking devices are arranged on the guardrails on the two sides of the bridge floor respectively; lifting devices are fixedly arranged on the walking devices, and the movable ends of the two lifting devices are correspondingly and fixedly connected with the cantilever trusses respectively; the walking device comprises a walking wheel, and a frequency converter and a driving motor which are fixedly connected with a central shaft of the walking wheel; the detection device comprises two laser receivers and two ultrasonic range finders, and the two laser receivers are arranged at the tops of the two cantilever trusses; the two ultrasonic range finders are respectively arranged between the truss and the guardrail, the ultrasonic range finders are fixedly connected with the cantilever truss through mounting rods, and the measuring ends of the ultrasonic range finders face the bridge floor. The device can be suitable for paving construction of a straight-line section and a curved-line section of a bridge floor, and the flatness and continuity of bridge floor paving concrete are improved.

The invention relates to the technical field of ultrasonic testing, in particular to a titanium alloy bar surface abrasion morphology detection method and system. The method comprises the following steps that non-contact scanning is conducted on the surface of a titanium alloy bar through a preset laser ultrasonic scanning system, a one-dimensional time domain ultrasonic signal is obtained, and the ultrasonic signal is decomposed into a plurality of IMF components; determining a point oscillation duration factor of each signal point in each IMF component; based on time domain window division, calculating an oscillation discreteness index of an oscillation duration factor of each point, and calculating frequency domain sharpness of each IMF component and an original signal; fusing the oscillation discreteness index and the frequency domain sharpness to generate a self-adaptive wavelet threshold parameter, denoising each IMF component by adopting the threshold parameter, and reconstructing to obtain an enhanced ultrasonic signal; and generating a titanium alloy bar surface wear morphology graph. According to the method, the accuracy and robustness of micro-wear detection on the surface of the titanium alloy bar in a high-noise environment are remarkably improved.

The invention provides a laser ultrasonic coaxial composite rock crushing device, and relates to the technical field of drilling equipment. The laser irradiation module comprises an optical isolator and a lens which are coaxially arranged; the ultrasonic drilling module comprises an ultrasonic transducer, a spiral groove amplitude-change pole, a first elastic piece and a drill bit, the upper end of the spiral groove amplitude-change pole is connected with the ultrasonic transducer, the lower end of the spiral groove amplitude-change pole is connected with the drill bit, the first elastic piece is connected with the lower end of the spiral groove amplitude-change pole, and a plurality of spiral grooves are formed in the outer wall of the spiral groove amplitude-change pole; the spiral groove amplitude-change pole and the drill bit are both arranged in a hollow mode to form a laser channel. The device has the beneficial effects that when the ultrasonic transducer drives the drill bit to drill a drilling point position, laser spots output by the optical isolator irradiate the drilling point position through the lens and the laser channel, and rocks are broken in a composite mode of the laser heat effect and the ultrasonic vibration effect; and when the melt on the surface of the rock is not formed, the drill bit realizes rock breaking, and the problem that the laser rock breaking efficiency is reduced due to the secondary effect is solved.

The invention relates to a semiconductor material laser stripping crack real-time online monitoring device and method based on laser ultrasound, and belongs to the technical field of semiconductor processing and nondestructive testing, the device combines a laser ultrasonic nondestructive testing technology and a laser stripping technology, laser is utilized to excite ultrasonic waves and detect the expansion condition of cracks in real time, and the laser stripping crack real-time online monitoring device and method based on laser ultrasound are obtained. Therefore, high-precision automatic detection of cracks is realized. By means of the device, real-time observation can be conducted on the expansion condition of cracks in the laser stripping piece, feedback data can be provided for a laser processing system, excessive expansion of the cracks is effectively avoided, and an innovative solution is provided for processing of third-generation semiconductor materials.

The invention relates to the technical field of laser ultrasound, and particularly discloses a multi-dominant-frequency laser ultrasonic holographic system and a design method.The system comprises a laser and a laser beam adjusting module used for receiving and adjusting laser beams, the laser beam adjusting module comprises a beam expanding lens and a collimating lens which are coaxially arranged, the beam expanding lens is used for adjusting the diameter of the laser beams, and the collimating lens is used for adjusting the diameter of the laser beams; the collimating mirror is used for collimating the laser beams so that the laser beams are kept parallel and focused; the frequency mixing ultrasonic holographic lens comprises a light focusing layer, a sound restraint layer, a light absorption layer, a sound matching layer and a sound holographic layer which are stacked in sequence, and the frequency mixing ultrasonic holographic lens is used for receiving the laser beams passing through the laser beam adjusting module so as to generate multiple stable single or multiple focusing ultrasonic sound fields with different preset frequencies in a time-sharing or simultaneous manner; and the focusing focus position and power can be adjusted, so that the device can be used for ultrasonic control and driving, ultrasonic detection imaging, low-power ultrasonic stimulation or power ultrasonic treatment and the like.

The present invention discloses a distributed laser ultrasonic detection system and method for defects in the R zone of a ribbed component. The geometric structure of the ribbed component is complex, and its R zone is a weak link in the manufacturing and service stages. The present invention includes a scanning device, a clamping device, a placement platform, two detectors, a beam splitter, a pulsed laser, a reflector, an industrial computer and a ribbed component to be tested. Laser ultrasound is used to excite ultrasonic waves on one side of the root rib of the ribbed component. Multiple detection lasers are distributed at different positions to receive echo signals, so as to quickly detect and classify and identify surface and near-surface defects in the R zone of the component with high efficiency and full coverage. The present invention can realize the rapid detection and accurate identification of defects of large wall panel components such as ribbed wall panels with complex geometric features.