1252 results about "Micro cracks" patented technology

The invention discloses a wind turbine generator hoisting construction tower drum operation system and a construction method thereof, and relates to the technical field of intelligent control. The problems that in the prior art, a static tension balance mechanism cannot restrain bending moment abrupt change, steel-concrete interface stress concentration causes microcrack propagation, the wave dynamic load compensation capacity is insufficient, and dynamic rigidity attenuation early warning is lacked are solved. Comprising a dynamic load prediction module, a multi-mode vibration suppression module, an offset compensation module and a digital twinborn decision module, a hoisting load is solved in real time through a multi-physics field coupling model and an improved time sequence deep learning algorithm, and interface crack propagation is suppressed in combination with traveling wave offset control and sweep frequency vibration. An improved Morison equation is adopted to drive a two-stage hydraulic servo to compensate a wave dynamic load, and a digital twin closed-loop correction mechanism is constructed based on a 5G URLLC protocol; the tower drum hoisting precision, the structural safety and the operation reliability under the complex working condition are remarkably improved.

The invention belongs to the technical field of concrete crack detection, and particularly discloses and provides a high-strength concrete construction crack detection system and method.The system comprises a multi-parameter cooperative sensing module, a construction crack recognition module, a crack risk analysis module and a crack early warning processing module. According to the invention, the temperature, humidity, strain and multispectral image data from a plasticity stage to a hardening stage are collected in real time through the multi-parameter cooperative sensing module, and crack characteristics are extracted by combining staged differential signal processing and a deep convolutional neural network, so that the detection precision of micro cracks and internal defects is remarkably improved. Meanwhile, multi-physics field data are fused, a crack evolution risk rate model is innovatively constructed, dynamic probability prediction before crack initiation is achieved, a grading disposal scheme is automatically triggered through risk grade division and a progressive early warning mechanism, drying shrinkage and temperature crack causes are effectively distinguished, the prevention and control efficiency is remarkably improved, and the method is suitable for large-scale popularization and application. And full-life-cycle accurate monitoring of the high-strength concrete is supported.

The invention discloses an egg surface microcrack detection system and method based on image analysis, and relates to the field of surface defect nondestructive detection.The method comprises the steps that a process identification interface module obtains a processing process identifier of an egg in real time; the multi-angle annular light source module is provided with a multi-band annular light source array comprising visible light and near-infrared LED lamp beads which are independently controlled, a polaroid group and a beam splitter prism are integrated, and visible light polarization images and near-infrared polarization images on the surfaces of the eggs are synchronously collected; the thermal excitation enhancement unit obtains a thermal infrared image; the process filtering module extracts the axial elongation of the mechanical stress microcrack after graded transportation, and calculates the mesh fractal dimension of the thermal stress microcrack after UV disinfection; the multi-modal feature fusion module generates a dual-channel crack probability graph; and the dynamic feedback control module outputs a micro-crack risk grade and adjusts the rotating speed of the objective table and the light source intensity. The method has the advantages that accurate judgment of mechanical and thermal stress cracks is realized, and curved surface reflection interference is broken through.

The invention relates to the technical field of visual inspection, in particular to a multi-mode industrial product dynamic defect detection system based on edge calculation. According to the method, by introducing a multi-modal image construction and enhancement mode, three-dimensional acquisition and enhanced expression of detail information of the surface of the wind power blade are realized, and by means of inter-modal image synchronization and a space registration mechanism, the consistency extraction capability of defect information under different sensor view angles is improved; through combination of density change trend analysis and direction mutation identification means, surface micro cracks, edge damages and other structural changes can be accurately identified in continuous frames, and further through multi-source discrimination and mutual elimination comparison of abnormal indexes, environmental interference and misjudgment risks are effectively eliminated, and the accuracy of the detection result is improved. Therefore, a stable defect track area with direction consistency and distribution continuity is screened out, accurate detection and partition identification of the surface defects of the wind power blade under the dynamic condition are achieved, and the reliability and precision of defect positioning are remarkably improved.

The invention discloses a zinc coating shedding performance detection method and system, particularly relates to the technical field of metal surface treatment quality detection, and is used for solving the problems of high misjudgment rate and insufficient detection precision caused by coating surface pseudo defect interference in the existing method. The method comprises the following steps: synchronously acquiring a multispectral reflection image and three-dimensional morphology data of the surface of a zinc coating through an industrial vision imaging device, extracting grain boundary distribution information based on multispectral data, and identifying radial pseudo defects in combination with a curvature manifold geodesic line energy gradient direction of the three-dimensional morphology; and further performing micro-crack topology analysis and grain boundary spatial correlation verification on the candidate region, eliminating texture interference and grain boundary overlapping regions, and finally outputting a high-confidence fall-off defect detection result, so that the identification capability of real defects under a complex galvanized surface is remarkably improved, and the method is suitable for automatic detection requirements of a high-speed continuous production line.

The invention relates to a tin ring automatic focusing laser soldering tin fixing and 3D welding spot detecting system, and belongs to the technical field of industrial automatic laser processing. The system is characterized in that a tin ring preparation module identifies pins in real time and dynamically optimizes winding parameters through visual positioning and a self-adaptive winding head, and performs defect identification and pre-repair analysis through multispectral imaging; the soldering tin positioning module is used for switching stations through a rotary table, and precise positioning and clamping of a product are realized by combining laser contour sensing and a focusing compensation algorithm; the laser tin soldering module can visually identify tin materials and automatically call welding parameters, laser power and action time are regulated and controlled in real time by establishing a regional heat conduction model, and gradient cooling is implemented after welding; and the 3D detection module adopts dual-mode scanning, constructs a welding spot three-dimensional model based on fusion data, recognizes microcracks through super-resolution processing, and discriminates the welding spot quality. And automation and intellectualization of the whole process from tin ring preparation to welding spot quality detection are achieved.

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 discloses a brittle material laser cutting thermal stress control method and system, and the method comprises the steps: obtaining real-time temperature distribution through infrared thermal imaging, combining finite element analysis and material characteristic dynamic data, constructing a thermal stress and fracture relation model, carrying out the iterative calculation of a thermal stress out-of-control threshold through a lambda algorithm, and determining a regulation boundary condition. According to the boundary condition, laser parameters are optimized, synchronous cooling airflow is introduced, the temperature gradient is dynamically controlled through an airflow pressure adjusting algorithm, historical data are processed through a convolutional neural network, the optimal laser parameter combination is predicted, in the cutting process, the microcrack diffusion state is monitored in real time, and auxiliary technological parameters are finely adjusted when necessary. The problem of fracture caused by out-of-control thermal stress in laser cutting of the brittle material is effectively solved, the cutting quality and efficiency are improved, and a new technical scheme is provided for precision machining of the brittle material.

The invention discloses a method for detecting the tensile property of a titanium alloy wire, and relates to the technical field of material detection.The method comprises the following steps that S1, sample preparation and microstructure pre-detection are conducted; s2, carrying out pre-stretching stress distribution equalization treatment; s3, determining an area where local plastic deformation possibly occurs in the sample; s4, performing dynamic tensile load increment control; s5, displacement field analysis is introduced, and data correction is carried out; s6, microcrack monitoring is carried out; s7, fracture mechanism analysis and fracture morphology characterization are carried out; and S8, constructing a dynamic damage evolution model. According to the method, by effectively simulating complex load conditions of the titanium alloy wire in actual use, test errors caused by constant-rate loading in a traditional method are avoided. In combination with dynamic correction of stress-strain data and a micro-crack monitoring technology, key behaviors of yield, plastic deformation, crack propagation and the like of the material under different loading conditions can be captured in real time, so that the tensile property of the material is accurately evaluated.

The invention belongs to the field of asphalt mixture performance analysis, and particularly discloses a fatigue performance analysis method for an asphalt mixture of an asphalt pavement, which comprises the following steps of: synchronously acquiring a dynamic strain field and a temperature field in a material by fusing an embedded sensor in a paving and rolling construction process; a temperature-strain coupled fatigue damage evolution model is combined to construct an on-line fatigue performance analysis system oriented to the whole construction process, so that a complex heat-force coupling environment and a non-uniform compaction process in actual paving operation are effectively restored; scale effect deviation and boundary condition distortion caused by difference between laboratory test piece preparation and on-site working conditions are remarkably reduced, and meanwhile, in the online detection process of the fatigue performance of the asphalt mixture, instant quantitative judgment of the performance state of the pavement structure is realized by positioning a damage remarkable overrun area; and the in-situ monitoring capability on the initial fatigue damage is fully reflected, so that the abnormal strain accumulation process before microcrack initiation can be captured.

The invention discloses an automobile seat framework machining defect detection method based on machine vision, and particularly relates to the technical field of defect detection. The method comprises the following steps: constructing a multi-angle image acquisition and edge reflection modeling module aiming at complex defects such as weld joint pseudo soldering, microcracks, hole site deviation and collapse deformation, extracting weld joint continuity, edge integrity and hole site geometric consistency characteristics by using a deep neural network, and generating a structural feature vector; defect type recognition and credibility scoring are completed through small sample anomaly modeling and Gaussian mixture model classification, sub-pixel-level coordinate labeling of defect positions is achieved in combination with a Gaussian fitting algorithm, a defect positioning map is output, traceability analysis and severity grading are conducted based on historical data comparison, and the defect positioning accuracy is improved. The method is suitable for industrial online detection and quality closed-loop control.

The invention discloses a method for improving the high-cycle fatigue performance of a Ti6Al4V titanium alloy, and belongs to the technical field of metal material processing, and the method comprises the following steps: S1, determining shot peening strengthening parameters based on material performance parameters and related standards; according to the method, high-amplitude residual compressive stress is introduced through shot peening strengthening, the stress state of the surface and the depth direction of the material is changed, accordingly, crack extension can be restrained, the fatigue life is prolonged, in addition, a plastic deformation layer is induced to be generated under the surface depth in the shot peening process, the microstructure of the material is improved, and the anti-fatigue performance of the material is improved; through femtosecond laser shock, surface defects can be effectively removed, the surface compactness can be improved, microcracks can be reduced, and a refined grain structure can be generated, so that the strength and toughness of the material are further enhanced, the high-cycle fatigue performance of the material is further improved, the two are combined, the residual stress state is optimized, and the surface integrity is improved. The fatigue performance of the Ti6Al4V titanium alloy is remarkably improved.

The invention provides a mobile phone glass quality detection method and system based on image detection, and relates to the technical field of image defect detection, and the method comprises the steps: configuring an imaging condition for collecting a mobile phone glass image, and collecting an original image of mobile phone glass according to the configured imaging condition; constructing a transparency enhancement algorithm according to a transparent background existing in the collected original image, and processing the original image according to the transparency enhancement algorithm to obtain an enhanced image; a crack boundary self-enhancement step is introduced, micro cracks and fuzzy scratches existing in an enhanced image are positioned, the enhanced image is marked according to the positioning result of the micro cracks and the fuzzy scratches, and a marked image is obtained. The phenomenon of false detection or missing detection easily occurring in mobile phone glass detection under a transparent background in related technologies is solved through a transparency enhancement algorithm; and the problem that boundary fuzzy defects such as microscopic cracks and fuzzy scratches with extremely low contrast are difficult to identify is solved through the crack boundary self-enhancement step.

The invention provides a metal material surface microcrack positioning method. The method comprises the following steps: applying a torsional load to a numerical model, calculating stress-strain distribution in a material, describing a crystal deformation behavior by adopting a crystal plasticity constitutive equation, and obtaining dislocation density distribution and a slip system activation condition in each crystal grain; according to the dislocation density distribution and the slip system activation condition, the position where microcracks are easy to form in the material is judged, and when the dislocation density exceeds a preset critical value and multiple activation slip systems exist, the position is determined to be the position where the microcracks are easy to form; according to the fracture mechanical parameters and the fracture toughness of the material, whether the microcracks are expanded or not is judged, when the stress intensity factor exceeds the fracture toughness, it is determined that the microcracks are expanded, and the crack expansion path is determined by calculating the direction of the maximum release rate.

The invention relates to the technical field of assembly welding, and particularly discloses an assembly welding positioning method and device for automobile parts. A welding state image between a target hush pipe and a target partition plate is collected through a camera; carrying out welding state mask segmentation on the welding state image by using an image identification and analysis algorithm based on computer vision, and then carrying out welding state feature extraction on the segmented welding detection area state mask image; and according to the expression obtained through neighborhood importance optimization of the extracted welding detection state characteristics, intelligent detection on whether defects exist in the welding state between the target hush pipe and the target partition plate or not is achieved. In this way, tiny defects such as tiny cracks and internal pores can be captured, and therefore the accuracy of defect recognition is improved. Moreover, the detection speed is greatly improved, the consistency and stability can be maintained, and the probability of missing detection or false detection is reduced, so that each welding point is ensured to be subjected to strict quality control.

The invention relates to the technical field of defect detection systems, and discloses a titanium alloy surface crack defect detection system based on deep learning. According to the system, a crack feature extraction module is used for collecting a titanium alloy surface image and extracting multi-scale crack features including crack trend distribution features and micro-crack density features; the multi-modal data fusion module is used for receiving the multi-scale crack features and performing space-time alignment on the multi-scale crack features and ultrasonic reflection wave features collected in real time to generate a fusion defect feature matrix; the dynamic learning engine module is used for constructing a crack propagation prediction model according to the historical change trend of the fusion defect feature matrix and outputting a dynamic defect response vector; the defect positioning module is used for mapping the dynamic defect response vector to a titanium alloy surface three-dimensional coordinate space to generate a defect position thermodynamic diagram; and the self-adaptive scanning control module is used for analyzing the defect confidence of each area in the defect position thermodynamic diagram and dynamically adjusting the scanning path and the focal length parameter of the industrial camera.

The invention discloses shrinkage-free aluminoferrite cement-based ultra-high performance concrete and a preparation method thereof, and belongs to the technical field of novel wall materials, and the shrinkage-free aluminoferrite cement-based ultra-high performance concrete comprises the following components: an activated cementing material, mineralized aggregate, an additive, reinforced fibers and mixing water. Due to the slow release effect of the methyl cellulose coating on the composite expanding agent, precise compensation of self-constriction is achieved, and contraction deformation in the curing and using process is effectively inhibited. Due to the unique mineral composition of the aluminoferrite cement, the early strength of the concrete is sharply improved, and the production cycle of prefabricated parts is greatly shortened. The steel fibers subjected to sand blasting and pre-wrapping modification can effectively bridge microcracks in the concrete and limit crack propagation; the polycarboxylate superplasticizer disperses the modified carbon nanofibers, crack initiation is inhibited from the microscopic level, and mechanical properties such as fracture resistance and impact resistance of the joint part and the prefabricated part are remarkably improved through cooperation of the polycarboxylate superplasticizer and the modified carbon nanofibers.

The invention discloses a preparation method of a nickel-based tungsten carbide laser cladding wear-resistant gradient coating, which comprises the following steps: step 1, preparing mixed powder of a transition layer, a functional layer and a repair layer; step 2, pretreating a matrix: removing oxide skin on the surface of the matrix, polishing to be smooth, and preheating the matrix to 350-500 DEG C; step 3, sequentially preparing a first functional layer, a transition layer, a second functional layer and a repair layer by adopting a laser cladding process; and 4, coating post-treatment is conducted, specifically, the surface of the repairing layer is polished to the specified thickness, and the defect-free wear-resistant gradient coating is formed. Through gradient component layered design, the functional layer adopts high tungsten carbide content to maximize wear resistance, and the transition layer relieves thermal expansion difference between the coating and a matrix, reduces interface stress and reduces crack initiation; according to the repairing layer, micro-cracks and air holes generated in the cladding process are filled through low-hardness nickel-based components, and the compactness and surface integrity of the coating are remarkably improved.

The invention provides anti-disturbance micro-expansion lightweight ultra-high performance concrete and a preparation method thereof. According to the concrete disclosed by the invention, the generation of micro cracks under disturbance can be effectively inhibited through the fiber bridging effect of the crystal whiskers and the temperature-shrinkage indented fibers and the micro pre-compressive stress of the temperature-shrinkage indented fibers under hydration exothermic excitation; the micro-crack healing effect of the nano-cellulose and the internal curing effect of the saturated pre-wetted coal gangue ceramsite cooperate to repair microstructure damage generated under strong disturbance, and the disturbance resistance of the concrete is further improved. The internal curing effect of the saturated pre-wetted coal gangue ceramsite and the expansion agent shrinkage compensation synergistically improve the volume stability of the concrete. The 28d compressive strength of the concrete is gt; compared with common ultra-high performance concrete, the volume weight of the ultra-high performance concrete is reduced by more than 20%, the anti-disturbance strength retention rate of the ultra-high performance concrete is greater than or equal to 95%, the ultra-high performance concrete shows excellent bonding and durability, the comprehensive performance of the ultra-high performance concrete is greatly improved, and the ultra-high performance concrete has important practical application value.

The invention discloses a method for analyzing the influence of a rock mass multi-scale structure on deep geothermal reservoir circular mining, and relates to the technical field of geothermal resource development and rock mechanics, and the method comprises the following steps: establishing a reservoir rock mass mechanical analysis model and a seepage heat transfer analysis model which simultaneously comprise a microscopic microcrack structure and a macroscopic crack structure; based on the reservoir seepage heat transfer analysis model, reservoir temperature field and seepage field analysis is carried out, and water pressure and temperature distribution results are transmitted to the mechanical analysis model; based on the reservoir mechanical analysis model, reservoir stress and deformation analysis under the heat-water-force coupling effect is carried out, and changes of microcosmic microcrack and macroscopic crack structures in the reservoir rock mass are obtained; the rock mass permeability evolution equation and the porosity evolution equation are adopted to calculate the reservoir rock mass permeability tensor and the porosity, and the reservoir rock mass permeability tensor and the porosity are transmitted to the seepage heat transfer analysis model; and solving the reservoir temperature field, the water pressure field and the mechanical response in the geothermal circulation exploitation process by adopting a seepage heat transfer analysis and mechanical analysis staggered iteration mode. By analyzing the reservoir temperature, the water pressure, the deformation evolution response and the reservoir permeability change in the geothermal exploitation process, geothermal exploitation design and protection can be reasonably carried out, and the application prospect is good.

The invention relates to the technical field of ball valves, provides an intelligent sensing modular ball valve and a control method, and designs a valve body module and a control module. The valve body module is integrated with a multi-mode sensor, comprises a spirally-distributed acoustic sensor array, a physical quantity sensor group and a valve element state detection sensor, and monitors fluid acoustic characteristics, pressure, temperature, flow, liquid level and valve element displacement and torque in real time. The control module analyzes sensor data through a data fusion algorithm, and early identification of cavitation faults and detection of micro-crack faults are achieved. The system adopts an 8-bit dynamic coding mechanism to accurately position the fault type, and adjusts the opening or torque of the actuator in a linkage manner. The method has multi-parameter cooperative sensing, early fault early warning and self-adaptive control capabilities, and the reliability and safety of the ball valve under complex working conditions are remarkably improved.

The invention relates to a semiconductor packaging structure and a packaging method thereof, and belongs to the technical field of semiconductor devices.The semiconductor packaging structure comprises a substrate, a chip, a radiator and a packaging shell, and further comprises an alloy needle matrix arranged below the radiator and a heated self-deformation fin arranged between the upper surface of the chip and the packaging shell; needle bodies of the alloy needle matrixes penetrate through the through holes in the substrate, needle tips of the alloy needle matrixes directly make contact with the back faces of the chips through the heat conduction springs, the heated self-deformation fins are unfolded through heating and abut against the top of the radiator, a double-channel vertical heat dissipation system is constructed, heat conduction paths from the chips to the radiator are directly broken through, and the double paths work in parallel. It is ensured that heat is vertically transmitted to the radiator through the shortest path, loss of traditional transverse heat diffusion is avoided, and the problems of thermal resistance accumulation caused by series connection of multiple layers of media, interface shear stress and micro cracks caused by mismatch of material thermal expansion coefficients of an existing semiconductor packaging structure are solved. And the problems of heat dissipation path failure and local high temperature of the chip caused thereby are solved.

The invention relates to the technical field of coal mining, in particular to a grouting reinforcement anti-seepage method for an underground coal mine, which comprises the following steps: cleaning and temporarily supporting a target area; scanning the surrounding rock by adopting intrinsic safety type detection equipment to obtain fracture parameters and generate a three-dimensional distribution diagram; designing a construction grouting hole and cleaning the hole; double-liquid grouting equipment is adopted, reinforced grout containing aggregate is injected firstly to fill large cracks, after the reinforced grout is initially set, impermeable grout such as acrylate is injected to block micro cracks, and grouting pressure and flow are monitored and controlled in real time; finally, strength and impermeability detection is carried out, and hole patching and grouting are carried out if the standard is not met; according to the method, through accurate detection, partition design, staged grouting and strict quality inspection, the problem that in a traditional method, the reinforcing effect and the seepage-proofing effect are difficult to cooperate is solved, integrated construction of high-strength reinforcing and efficient seepage-proofing of the surrounding rock is achieved, and the engineering quality and efficiency are improved.

The invention provides a carbon fiber composite material microcrack image segmentation method based on a two-stage super-resolution dynamic attention network, and the method comprises the steps: collecting a microscopic image of a to-be-detected carbon fiber composite material, and carrying out the preprocessing of the image, so as to improve the discrimination between a crack and a background; scanning the preprocessed image by adopting a multi-scale sliding window, carrying out microcrack feature extraction in combination with morphological Top-hat transformation, and positioning a candidate region with microcracks; cutting an image corresponding to the candidate region into sub-images, inputting the sub-images into a pre-trained super-resolution reconstruction network, and amplifying the sub-images to 2-8 times of the original size to obtain a high-resolution candidate region image; inputting the super-resolution enhanced candidate region image into a pre-trained convolutional neural network model for pixel-level crack segmentation to obtain a segmentation result of cracks in the candidate region; and mapping the segmented micro-crack region back to an original image coordinate system, marking the position and shape of the crack on the original image, and outputting a final micro-crack segmentation result.

The invention relates to a hard and brittle material large depth-diameter ratio small hole laser milling-precision grinding process and a device thereof.The method comprises the steps that firstly, a mapping relation between an inlet aperture and laser parameters is established through a response surface method, laser machining parameters are determined, and laser machining parameters are obtained on the basis of an optical image acquisition system; a pulse laser is adopted to prepare the large-depth-diameter-ratio micro through hole with the accurate and controllable ablation amount, the grinding amount is reduced, meanwhile, the strength, hardness or fracture toughness of materials at the machining position is reduced, and therefore the grinding force for machining hard and brittle materials and tool abrasion are reduced; and secondly, machining damage such as microcracks, recast layers and taper caused by laser machining is removed through grinding machining, and the machining quality of the small hole with the large depth-diameter ratio is improved. The device mainly comprises a machine body, a workbench, a laser machining main shaft, a grinding machining main shaft, a differential interference difference microscope, an optical CCD camera and an X-axis and Y-axis servo driving module, different machining processes and in-situ detection can be completed on the same machine tool, the problems of secondary clamping, poor repeated positioning precision and the like of workpieces are solved, the machining efficiency is improved, and the machining cost is reduced. According to the method, bottom hole laser machining of the hard and brittle materials is highly combined with grinding hole repairing and hole expanding, high-quality and high-efficiency machining of the hard and brittle materials is achieved, tool abrasion is reduced, and the machining cost is reduced.

The invention relates to the technical field of aluminum profile processing, in particular to an acoustic emission signal detection method for microscopic cracks in an aluminum profile welding joint area, which comprises the following steps: S1, welding joint preparation: cleaning an aluminum profile to be detected; s2, acoustic emission sensor arrangement: comprehensive monitoring and signal acquisition are carried out on a welding joint; s3, signal acquisition and processing: starting an acoustic emission sensor to acquire an acoustic emission signal; s4, multi-modal data fusion: fusing the acoustic emission signal and the physical state data into comprehensive data; s5, self-adaptive crack propagation prediction: identifying potential microscopic crack characteristics, and predicting future development of microscopic cracks; and S6, evaluation and report generation: generating an evaluation report. According to the method, the microscopic crack characteristics and the development trend of the welding joint area can be accurately identified and evaluated, the accuracy and the real-time performance of detection are remarkably improved, and effective signals and background noise can be efficiently separated.

The invention discloses an ion beam polishing method for coupled silicon carbide in-situ growth based on quantum dots, and belongs to the technical field of SiC surface polishing. The preparation method of the SiC material with the quantum dot sacrificial layer grown in situ comprises the following steps: mixing a lead source, a cesium source and a solvent to obtain a CsPbBr3 precursor solution; and dropwise adding the CsPbBr3 precursor solution to the surface of the SiC material, flattening, heating for crystallization, and annealing to obtain the SiC material with the quantum dot sacrificial layer grown in situ. According to the ion beam polishing method based on quantum dot coupling silicon carbide in-situ growth, the quantum dot layer serves as the sacrificial layer of the SiC wafer, the thickness of the sacrificial layer can be effectively reduced, the flatness of the SiC surface can be remarkably improved, and the good fluorescence labeling effect can be achieved. The CsPbBr3 quantum dot prepared by the method has extremely small nano size, can deeply fill micro cracks and micro-nano scratches on the surface of a SiC wafer, is completely coupled with the micro cracks on the surface of the SiC wafer, and realizes accurate filling of defects.

According to the in-pipe microcrack circumferential positioning method based on the ultrasonic guided wave second harmonic, the second harmonic is generated by means of the fundamental wave of the axial symmetry mode, circumferential positioning of the microcrack in a tubular structure is achieved according to the mode and the amplitude of the second harmonic, and the microcrack in the pipeline can be quickly positioned before the microcrack of the pipeline develops into a macroscopic crack. The microcracks can be found in time and accurately positioned, so that the pipeline can be accurately maintained in time, further evolution of the microcracks and accidents are avoided, safe operation of the pressure pipeline is guaranteed, and the time cost and the economic cost of manual troubleshooting can be reduced.

The invention belongs to the technical field of metal crack detection, and discloses a metal microcrack ultrasonic detection method, which comprises the following modules: an ultrahigh frequency composite array probe with a center frequency dynamic adjustable range of 5-50 MHz; the dual-mode excitation and receiving module is used for independently generating a pulse reflection mode excitation signal and a diffraction mode chirp frequency modulation signal; the phase-controlled synthetic aperture dynamic focusing module is used for realizing + / -60-degree deflection and sub-wavelength level focusing of acoustic beams; the nonlinear harmonic enhancement module is used for exciting a crack nonlinear effect by superposing 1-2MHz fundamental waves; and a time-space-frequency three-domain data fusion module. According to the method, signal-to-noise ratio collapse caused by the diffraction effect in a traditional method is overcome, more importantly, the system has low-frequency penetrability and high-frequency resolution at the same time due to 80%-120% of broadband coverage of chirp frequency modulation signals, the diffraction signal gain is increased by 20 dB or above, a near-surface blind area is compressed to be within 0.2 mm, and the system can be applied to the field of radar imaging. And the core pain point of missing detection of the near-surface microcracks of the thin-wall component is solved.

The invention discloses an underground safety monitoring and polling device, and belongs to the technical field of coal mine safety polling. Comprising a conveying belt body and an inspection robot. A jacking and extending assembly is installed between the inspection robot and the supporting plate, when the detected cracks on the conveying belt body need to be repaired or marked, the jacking and extending assembly drives the supporting plate to descend and abut against the conveying belt body, and the walking conveying belt body drives the inspection robot and the conveying belt body to move synchronously; a cleaning roller is arranged on the other side, close to the supporting plate, of the bottom of the inspection robot, two spraying heads are arranged on the side, close to the supporting plate, of the cleaning roller at equal intervals, and a transmission mechanism drives the corresponding spraying heads to distinguish slight cracks or serious cracks, detected by the inspection robot, on the conveying belt body; according to the invention, respective processing can be carried out according to the crack degree, the detection efficiency is effectively improved, and the problem that an existing robot lacks an effective processing means is solved.