Ultrasonic phase control scanning detection method for defects of cladding layer

Abstract

The invention relates to the technical field of nondestructive testing, in particular to an ultrasonic phase control scanning detection method for cladding layer defects, which comprises the following steps: carrying out ultrasonic phase control scanning on a cladding layer to obtain a reflection signal, dividing defect types based on defect characterization parameters, determining a single defect area of transverse crack defects according to the crack characterization parameters, and detecting the defects of the cladding layer according to the single defect area. According to the bubble deviation parameter and the crack characterization parameter, generating a simulated crack characterization parameter to determine a single defect area corresponding to the bubble defect; determining an overlapped defect area according to the single defect areas corresponding to the different defects, judging whether the overlapped defect area is a hidden defect area or not based on the hidden characteristic parameters, and determining the hidden defect area as a structure damaged area, and judging whether the non-hidden defect area is a structure damaged area or not according to the area of the overlapped defect area and the bubble defect number corresponding to the overlapped defect area. The accuracy of the ultrasonic phase control scanning detection method for the defects of the cladding layer is improved.

Description

Technical Field

[0001] This invention relates to the field of nondestructive testing technology, and in particular to an ultrasonic phased array scanning method for detecting defects in cladding layers. Background Technology

[0002] Cladding technology, as an advanced surface modification and remanufacturing technology, has been widely used in key industrial fields such as aerospace, energy and power, and heavy machinery. However, during the rapid melting and solidification process, cladding layers are prone to internal defects such as bubbles and cracks due to factors such as fluctuations in process parameters, material properties, and thermal stress. It is difficult to accurately assess the severity of defects and their actual damage to structural integrity based solely on amplitude. Especially when multiple defects are closely adjacent or overlap in space, it is crucial to conduct more detailed analysis of overlapping areas according to different defect types. This invention aims to effectively identify and determine the trends of potential risk areas through ultrasonic phased array scanning detection, thereby further realizing more comprehensive, accurate, and forward-looking non-destructive testing of the internal quality of cladding layers.

[0003] Chinese Patent Application Publication No. CN119355133A discloses an invention relating to the field of nondestructive testing technology, specifically a method for detecting defects in lead seals based on phased array ultrasonic testing technology. The method includes the following steps: surface three-dimensional data acquisition; data processing and modeling; preparation for phased array ultrasonic testing; ultrasonic scanning; data analysis and defect identification; defect localization and quantification; and evaluation and report generation. This invention combines laser scanning with phased array ultrasonic testing. Laser scanning acquires the microscopic and macroscopic features of the lead seal surface, generating a precise three-dimensional geometric model that reproduces the physical morphology of the lead seal, providing an intuitive reference framework for subsequent phased array ultrasonic testing. Combined with adaptive frequency adjustment and dynamic focus control technology, it identifies different regions of the lead seal material and their heterogeneity, adjusting the focusing position and depth of the ultrasonic beam in real time, thus improving the flexibility and accuracy of defect detection.

[0004] The existing technology also has the following problems: the existing technology does not take into account the generation of deviation parameters by simulating easily detectable defects to improve the detection accuracy of difficult-to-detect defects. Summary of the Invention

[0005] Therefore, the present invention provides an ultrasonic phased array scanning detection method for cladding layer defects, which overcomes the problem in the prior art that it does not take into account the generation of deviation parameters by simulating easily detectable defects to improve the detection accuracy of difficult-to-detect defects.

[0006] To achieve the above objectives, the present invention provides an ultrasonic phased array scanning method for detecting defects in the cladding layer, comprising: The cladding layer is subjected to ultrasonic phased scanning to obtain the reflected signal. Based on the echo amplitude and pulse width of the reflected signal, defect characterization parameters are generated to classify the defect types, which include transverse crack defects, bubble defects and vertical crack defects. Crack length and crack depth of the transverse crack defect closest to the bubble defect are collected to generate crack characterization parameters to determine the single defect region of the transverse crack defect. The maximum diameter and bubble depth of the bubble defect are collected to generate bubble characterization parameters. The maximum diameter and bubble depth of the transverse crack defect after the functionalized fluid is applied are obtained to generate simulated bubble characterization parameters. Based on the bubble characterization parameters and the simulated bubble characterization parameters, bubble deviation parameters are calculated. Based on the bubble deviation parameters and the crack characterization parameters, simulated crack characterization parameters are generated to determine the single defect region corresponding to the bubble defect. Based on the single defect region corresponding to different defects, the overlapping defect region is determined. The hidden feature parameters are generated based on the defect center spacing and defect depth difference of the overlapping defect region to determine whether the overlapping defect region is a hidden defect region. In response to the overlapping defect region being a hidden defect region, the hidden defect region is determined as a structurally damaged region. In response to the overlapping defect region being a non-hidden defect region, the area of ​​the overlapping defect region and the number of bubble defects corresponding to the overlapping defect region are combined to determine whether the non-hidden defect region is a structurally damaged region.

[0007] Furthermore, the process of generating defect characterization parameters based on the echo amplitude and pulse width of the reflected signal to classify defect types includes, The amplitude factor is determined by the ratio of the difference between the echo amplitude and the reference echo amplitude to the reference echo amplitude. The pulse factor is defined as the ratio of the difference between the pulse width and the reference pulse width to the reference pulse width. The weighted sum of the amplitude factor and the pulse factor is determined to be a defect characterization parameter.

[0008] Furthermore, the generation of defect characterization parameters based on the echo amplitude and pulse width of the reflected signal to classify defect types, wherein, If the defect characterization parameter is less than or equal to the first defect characterization threshold, the defect type is determined to be a bubble defect. If the defect characterization parameter is greater than the first defect characterization threshold and less than the second defect characterization threshold, then the defect type is determined to be a vertical crack defect. If the defect characterization parameter is greater than or equal to the second defect characterization threshold, the defect type is determined to be a transverse crack defect.

[0009] Furthermore, the process of collecting the crack length and crack depth of the transverse crack defect closest to the bubble defect to generate crack characterization parameters includes, The ratio of the crack length to the reference crack length is determined as the length factor; The ratio of the crack depth to the reference crack depth is determined as the crack depth factor; The weighted sum of the length factor and the crack depth factor is determined to be a crack characterization parameter.

[0010] Furthermore, the process of collecting the maximum diameter and depth of the bubble defect to generate bubble characterization parameters includes, The ratio of the maximum diameter to the reference maximum diameter is determined as the diameter factor; The ratio of the bubble depth to the reference bubble depth is determined as the pore depth factor; The weighted sum of the diameter factor and the pore depth factor is determined to be a bubble characterization parameter.

[0011] Furthermore, the process of obtaining the maximum diameter and bubble depth of the transverse crack defect after applying the functionalized fluid to generate simulated bubble characterization parameters includes, The weighted sum of the diameter factor and pore depth factor of the transverse crack defect after the functionalized fluid is applied is determined as a characterization parameter for the simulated bubble. The ratio of the difference between the bubble characterization parameters and the simulated bubble characterization parameters is determined as the bubble deviation parameter.

[0012] Furthermore, the process of generating concealed feature parameters based on the defect center spacing and defect depth difference of the overlapping defect regions to determine whether the overlapping defect regions are concealed defect regions includes, The absolute value of the distance between the centers of any two defects is the defect distance, and the ratio of the mean of the defect distances to the maximum defect center distance is determined as the distance factor. The absolute value of the depth difference between any two defects is the defect depth difference, and the ratio of the mean of the depth differences of each defect to the maximum defect depth difference is the depth factor. The weighted sum of the spacing factor and the depth factor is determined to be the hidden feature parameter.

[0013] Furthermore, based on concealment feature parameters, it is determined whether the overlapping defect region is a concealed defect region, wherein, If the concealed feature parameter is less than or equal to the concealed feature threshold, then the overlapping defect region is determined to be a non-concealed defect region. If the hidden feature parameter is greater than the hidden feature threshold, then the overlapping defect region is determined to be a hidden defect region.

[0014] Furthermore, the process of determining the overlapping defect regions based on the single defect regions corresponding to different defects includes, Using the center of the crack as the origin and the longest distance from the center to the edge of the crack as the radius, we can divide the area into single defect regions corresponding to transverse crack defects and vertical crack defects respectively. The area covered by at least two single defect areas is identified as the overlapping defect area.

[0015] Furthermore, the process of determining whether the non-hidden defect region is a structurally damaged region by combining the area of ​​the overlapping defect region and the number of bubble defects corresponding to the overlapping defect region includes, If the area is greater than the area threshold and the number of bubble defects is greater than the number of bubble defects threshold, then the non-hidden defect area is determined to be a structurally damaged area.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention reflects the geometric extension of the defect in the direction of sound wave propagation through pulse width. Bubbles reflect a narrower echo pulse, while cracks produce a wider echo pulse. Due to the different angles between transverse cracks and vertical cracks and their reflected signals, their pulse widths also have distinguishable characteristics. By combining the echo amplitude and pulse width to generate defect characterization parameters, the system can distinguish between bubbles, transverse cracks, and vertical cracks, reducing misclassification caused by interference such as material attenuation and interface noise. The quantitative classification method based on clear physical characteristics greatly improves the detection efficiency, thereby further improving the accuracy of the ultrasonic phased array scanning detection method for cladding layer defects.

[0017] Furthermore, this invention identifies and quantifies the cracks interacting with the bubble by collecting the length and depth of the transverse crack closest to the bubble. The generated crack characterization parameters define the original severity and geometric characteristics of the defect, thereby determining the range of the single defect area that needs to be repaired. The maximum diameter and depth of the bubble are collected to quantify the original state of the internal cavity defect. The bubble depth and diameter together determine its potential damage to structural integrity. A functionalized fluid with properties such as solidification or gel formation is applied to the crack. The maximum diameter and depth of the transverse crack of the simulated bubble are measured, forming an objective comparison of defect morphology parameters, thereby further improving the accuracy of the ultrasonic phased array scanning detection method for cladding layer defects.

[0018] Furthermore, this invention reflects the morphological changes of the simulated bubbles in the transverse crack after functionalized fluid covers the transverse crack using bubble deviation parameters. It calculates the deviation between the parameters collected by the ultrasonic phased array scanning detection device before and after the simulated bubble morphology. Based on the identified defect types and sizes, it generates a single defect region for each defect. By observing the geometric intersection of these simulated regions, it accurately defines overlapping defect regions, achieving a transformation from signal processing to defect entity analysis. The center-to-center distance of defects determines the intensity of the interaction between defects; the smaller the distance, the denser the positions of the defects on the cladding layer. The defect depth difference affects the interaction of defects in the stress field. The center-to-center distance and the defect depth difference are integrated into a comprehensive hidden characteristic parameter, providing a reliable basis for judging hidden defect regions, thereby further improving the accuracy of the ultrasonic phased array scanning detection method for cladding layer defects.

[0019] Furthermore, this invention identifies overlapping defect areas as hidden defect areas and directly determines them as structurally damaged areas. If there is a strong geometric correlation between the defects, such as small spacing and similar depth, it indicates the risk of crack connection and bubble instability. If overlapping defect areas are identified as non-hidden defect areas, their structural damage is determined by area and number of bubble defects. When the risk of direct series connection between defects is not high, it is necessary to assess whether they pose a threat as a cluster by weakening the effective load-bearing area of ​​the material or forming a complex stress disturbance zone. Large-area or multiple bubble aggregations, even without close interaction, will significantly reduce the overall stiffness and strength of the area. Taking into account both area and bubble density improves the requirements for screening damaged areas, thereby further improving the accuracy of the ultrasonic phased array scanning detection method for cladding layer defects. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating the steps of the ultrasonic phased array scanning method for detecting defects in the cladding layer according to an embodiment of the present invention. Figure 2 This is a logic decision diagram for classifying defect types based on defect characterization parameters in an embodiment of the present invention; Figure 3 This is a logic diagram for determining whether an overlapping defect region is a hidden defect region in an embodiment of the present invention. Figure 4 This is a logic diagram for determining whether a non-hidden defect area is a structurally damaged area in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0022] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0023] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] Please see Figure 1 The diagram shows a flowchart of the ultrasonic phased array scanning method for detecting cladding layer defects according to an embodiment of the present invention. The ultrasonic phased array scanning method for detecting cladding layer defects according to an embodiment of the present invention includes: Step S1: Perform ultrasonic phased array scanning on the cladding layer to obtain the reflected signal. Based on the echo amplitude and pulse width of the reflected signal, generate defect characterization parameters to classify the defect types. The defect types include transverse crack defects, bubble defects and vertical crack defects. Step S2: Collect the crack length and crack depth of the transverse crack defect closest to the bubble defect to generate crack characterization parameters to determine the single defect region of the transverse crack defect; collect the maximum diameter and bubble depth of the bubble defect to generate bubble characterization parameters. Step S3: Obtain the maximum diameter and bubble depth of the transverse crack defect after the functionalized fluid is applied to generate simulated bubble characterization parameters. Calculate bubble deviation parameters based on the bubble characterization parameters and simulated bubble characterization parameters. Generate simulated crack characterization parameters based on the bubble deviation parameters and crack characterization parameters to determine the single defect region corresponding to the bubble defect. Step S4: Determine overlapping defect regions based on the single defect regions corresponding to different defects, and generate hidden feature parameters based on the defect center spacing and defect depth difference of the overlapping defect regions to determine whether the overlapping defect regions are hidden defect regions. Step S5: In response to the overlapping defect area being a hidden defect area, the hidden defect area is determined as a structurally damaged area; in response to the overlapping defect area being a non-hidden defect area, the area of ​​the overlapping defect area and the number of bubble defects corresponding to the overlapping defect area are combined to determine whether the non-hidden defect area is a structurally damaged area.

[0025] It is understandable that when functionalized fluid is applied to transverse crack defects to simulate the interference with sound beam propagation when an ultrasonic phased array scanning device detects bubble defects, the detection angle must be consistent with the detection angle of bubble defects when the transverse crack defects after being coated with functionalized fluid are detected again.

[0026] Specifically, the functionalized fluid can be lipid-coated perfluoropentane functionalized microbubble fluid, which consists of a phosphatidylcholine monolayer lipid shell and a perfluoropentane droplet core. The microbubble particle size is 5μm to 20μm, and the mass concentration is 0.1% to 0.5%. When determining the application amount, for transverse crack defects with a length of 1mm to 10mm and a depth of 0.5mm to 5mm, the application amount is measured according to the crack length, and the application amount is 0.01mL / cm to 0.1mL / cm. The maximum application amount for a single crack should not exceed 0.5mL, and the crack should be completely filled with no obvious liquid accumulation on the surface.

[0027] Specifically, the preparation method of lipid-coated perfluoropentane functionalized microbubble fluid is as follows: phosphatidylcholine is dissolved in anhydrous ethanol to prepare a phosphatidylcholine ethanol solution with a mass concentration of 0.5% to 1%. Perfluoropentane is mixed with the phosphatidylcholine ethanol solution at a volume ratio of 1:10 to 1:20, and the mixture is placed in an ultrasonic cell disruptor and ultrasonically dispersed for 10 to 15 minutes at a power of 200W to 300W and a frequency of 20kHz to 30kHz to form a uniform lipid-coated perfluoropentane functionalized microbubble fluid. The formulation ratio of this preparation method can be adjusted according to the usage to ensure that the performance of the finished product does not significantly decrease within 7 days of refrigerated storage, which will not be elaborated further here.

[0028] Specifically, the process of generating defect characterization parameters based on the echo amplitude and pulse width of the reflected signal to classify defect types includes, The amplitude factor is determined by the ratio of the difference between the echo amplitude and the reference echo amplitude to the reference echo amplitude. The pulse factor is defined as the ratio of the difference between the pulse width and the reference pulse width to the reference pulse width. The weighted sum of the amplitude factor and the pulse factor is determined as the defect characterization parameter.

[0029] Specifically, the sum of the weighting coefficients of the amplitude factor and the pulse factor is 1. Since the echo amplitude has a greater influence on the determination of the defect type, the weighting coefficient of the amplitude factor is 0.6 and the weighting coefficient of the pulse factor is 0.4.

[0030] Specifically, the reference echo amplitude is the average of the echo amplitudes of several reflected signals when detecting a defect-free cladding layer in historical data, and the reference pulse width is the average of the pulse widths of several reflected signals when detecting a defect-free cladding layer in historical data.

[0031] Specifically, the ultrasonic phased array probe emits ultrasonic pulses that are incident on the metal body. The defects generate reflected echoes, which are received by the probe and form a time-domain reflection signal waveform. In the reflected signal waveform, the peak point of the defect echo is found, and the voltage amplitude at the peak point is read, which is the echo amplitude. The rising edge start point and falling edge end point of the defect echo are located from the time-domain reflection signal, and the time difference between the two edge points is measured, which is the pulse width.

[0032] Please see Figure 2 As shown, this is a logic diagram for classifying defect types based on defect characterization parameters according to an embodiment of the present invention. Defect characterization parameters are generated based on the echo amplitude and pulse width of the reflected signal to classify defect types. If the defect characterization parameter is less than or equal to the first defect characterization threshold, the defect type is determined to be a bubble defect. If the defect characterization parameter is greater than the first defect characterization threshold and less than the second defect characterization threshold, then the defect type is determined to be a vertical crack defect. If the defect characterization parameter is greater than or equal to the second defect characterization threshold, the defect type is determined to be a transverse crack defect. The first defect characterization threshold is less than the second defect characterization threshold.

[0033] It is understandable that a transverse crack is a crack whose crack surface is parallel to the surface of the cladding layer and whose crack direction extends along the horizontal direction of the cladding layer, while a vertical crack is a crack whose crack surface is perpendicular to the surface of the cladding layer and whose crack direction extends along the depth direction of the cladding layer.

[0034] Specifically, the first defect characterization threshold is the product of the first defect characterization reference value and the first defect characterization factor. The first defect characterization reference value is the average defect characterization value calculated when bubble defects are detected on cladding layers of similar quality in historical data. The first defect characterization factor can be set by those skilled in the art according to the accuracy requirements for detecting bubble defects in cladding layers. The higher the accuracy requirement, the smaller the value should be. The value range can be [1.0, 1.2], preferably 1.1.

[0035] Specifically, the second defect characterization threshold is the product of the second defect characterization reference value and the second defect characterization factor. The defect characterization reference value is the average defect characterization value calculated when transverse crack defects are detected on cladding layers of similar quality in historical data. The second defect characterization factor can be set by those skilled in the art according to the accuracy requirements for detecting transverse crack defects in cladding layers. The higher the accuracy requirement, the smaller the value should be. The value range can be [1.1, 1.3], and preferably, it can be 1.2.

[0036] Specifically, this invention uses pulse width to reflect the geometric extension of defects along the direction of sound wave propagation. Bubbles reflect narrower echo pulses, while cracks produce wider echo pulses. Transverse and vertical cracks also exhibit distinguishable differences in pulse width due to their different angles with the sound beam. By combining echo amplitude and pulse width to generate defect characterization parameters, the system can differentiate between bubbles, transverse cracks, and vertical cracks, reducing misclassification caused by material attenuation, interface noise, and other interferences. This quantitative classification method based on clear physical characteristics significantly improves detection efficiency, thereby further enhancing the accuracy of ultrasonic phased array scanning detection of cladding layer defects. Specifically, the process of collecting crack length and crack depth data from the transverse crack closest to the bubble defect to generate crack characterization parameters includes: The ratio of the crack length to the reference crack length is determined as the length factor; The ratio of the crack depth to the reference crack depth is determined as the crack depth factor; The weighted sum of the length factor and the crack depth factor is determined as the crack characterization parameter.

[0037] Specifically, the sum of the weighting coefficients of the length factor and the crack depth factor is 1. Since the crack length and crack depth have similar influence on the determination of the defect trend of transverse cracks, the weighting coefficient of the length factor is 0.5 and the weighting coefficient of the crack depth factor is 0.5.

[0038] Specifically, the reference crack length is the average crack length of several transverse cracks when the transverse crack defects detected in historical data do not affect the cladding layer structure, and the reference pulse width is the average crack depth of several transverse cracks when the transverse crack defects detected in historical data do not affect the cladding layer structure.

[0039] Specifically, the process of collecting the maximum diameter and depth of bubble defects to generate bubble characterization parameters includes, The ratio of the maximum diameter to the reference maximum diameter is determined as the diameter factor; The ratio of the bubble depth to the reference bubble depth is determined as the pore depth factor; The weighted sum of the diameter factor and the pore depth factor is determined to be the bubble characterization parameter.

[0040] Specifically, the sum of the weighting coefficients of the diameter factor and the pore depth factor is 1. Since the maximum diameter and the bubble depth have similar influence on the defect trend of bubble defects, the weighting coefficient of the diameter factor is 0.5 and the weighting coefficient of the pore depth factor is 0.5.

[0041] Specifically, the benchmark maximum diameter is the average of the maximum diameters of several bubble defects detected in historical data when the bubble defects do not affect the cladding layer structure, and the benchmark bubble depth is the average bubble depth of several bubble defects detected in historical data when the bubble defects do not affect the cladding layer structure.

[0042] Specifically, this invention identifies and quantifies the cracks interacting with the bubble by collecting the length and depth of the transverse crack closest to the bubble. The generated crack characterization parameters define the original severity and geometric characteristics of the defect, thereby determining the range of the single defect area that needs to be repaired. The maximum diameter and depth of the bubble are collected to quantify the original state of the internal cavity defect. The bubble depth and diameter together determine its potential damage to structural integrity. A functionalized fluid with properties such as solidification or gel formation is applied to the crack. The maximum diameter and depth of the transverse crack of the simulated bubble are measured to form an objective comparison of defect morphology parameters, thereby further improving the accuracy of the ultrasonic phased array scanning detection method for cladding layer defects.

[0043] Specifically, the process of obtaining the maximum diameter and bubble depth of the transverse crack defect after applying the functionalized fluid to generate simulated bubble characterization parameters includes, The weighted sum of the diameter factor and pore depth factor of the transverse crack defect after the functionalized fluid is applied is determined as a characterization parameter for the simulated bubble. The ratio of the difference between the bubble characterization parameters and the simulated bubble characterization parameters is defined as the bubble deviation parameter.

[0044] Specifically, the sum of the weighting coefficients of the diameter factor and the hole depth factor is 1. Since the maximum diameter and the bubble depth have similar influence on the defect trend of transverse crack defects in the simulated bubble defects, the weighting coefficient of the diameter factor is 0.5 and the weighting coefficient of the hole depth factor is 0.5.

[0045] Specifically, the bubble deviation parameter = |bubble characterization parameter - simulated bubble characterization parameter| / bubble characterization parameter.

[0046] Specifically, if the bubble characterization parameter is less than or equal to the simulated bubble characterization parameter, then the simulated crack characterization parameter = crack characterization parameter x (1 + bubble deviation parameter); if the bubble characterization parameter is greater than the simulated bubble characterization parameter, then the simulated crack characterization parameter = crack characterization parameter x (1 - bubble deviation parameter).

[0047] Specifically, the process of generating concealed feature parameters based on the defect center spacing and defect depth difference of overlapping defect regions to determine whether an overlapping defect region is a concealed defect region includes the following steps: The absolute value of the distance between the centers of any two defects is the defect distance, and the ratio of the mean of the defect distances to the maximum defect center distance is determined as the distance factor. The absolute value of the depth difference between any two defects is the defect depth difference, and the ratio of the mean of the depth differences of each defect to the maximum defect depth difference is the depth factor. The weighted sum of the spacing factor and the depth factor is determined to be the hidden feature parameter.

[0048] Specifically, the maximum defect center spacing is the maximum value of the center spacing between any two defects in several overlapping defect regions, and the maximum defect depth difference is the maximum value of the depth difference between any two defects in several overlapping defect regions.

[0049] Specifically, the sum of the weighting coefficients of the spacing factor and the depth factor is 1. Since the center-to-center distance between the defects in the overlapping defect area has a greater impact on determining whether the overlapping defect area is a hidden defect area than the depth difference, the weighting coefficient of the spacing factor is 0.7 and the weighting coefficient of the depth factor is 0.3.

[0050] Specifically, this invention uses bubble deviation parameters to reflect the changes in the morphology of simulated bubbles in transverse cracks after functionalized fluid covers them. It calculates the deviation between parameters collected by an ultrasonic phased-array scanning detection device before and after the simulated bubble morphology. Based on the identified defect types and sizes, it generates a single defect region for each defect. By observing the geometric intersection of these simulated regions, it accurately defines overlapping defect regions, achieving a transformation from signal processing to defect entity analysis. The center-to-center distance of defects determines the intensity of the interaction between defects; the smaller the distance, the denser the positions of the defects on the cladding layer. The defect depth difference affects the interaction of defects in the stress field. The center-to-center distance and the defect depth difference are integrated into a comprehensive hidden characteristic parameter, providing a reliable basis for judging hidden defect regions, thereby further improving the accuracy of the ultrasonic phased-array scanning detection method for cladding layer defects.

[0051] Please see Figure 3 As shown, this is a logic diagram for determining whether an overlapping defect region is a hidden defect region according to an embodiment of the present invention. The determination of whether an overlapping defect region is a hidden defect region is based on hidden feature parameters. If the hidden feature parameter is less than or equal to the hidden feature threshold, the overlapping defect area is determined to be a non-hidden defect area. If the hidden feature parameter is greater than the hidden feature threshold, then the overlapping defect area is determined to be a hidden defect area.

[0052] Specifically, the purpose of setting a hidden feature threshold is to characterize the deviation between overlapping defect areas. The hidden feature threshold can be set in the range of [0.8, 0.9].

[0053] Specifically, the process of determining overlapping defect regions based on the individual defect regions corresponding to different defects includes: Using the center of the crack as the origin and the longest distance from the center to the edge of the crack as the radius, we can divide the area into single defect regions corresponding to transverse crack defects and vertical crack defects respectively. The area covered by at least two single defect areas is identified as the overlapping defect area.

[0054] Specifically, the single defect region of a bubble defect is determined based on the single defect region corresponding to the crack characterization parameter that is equal to the simulated crack characterization parameter.

[0055] Specifically, the area of ​​a single defect region can be calculated using the formula for the area of ​​a circle, S=πR², where S is the area in mm², π is pi (taken as 3.14), and R is the radius in mm.

[0056] Specifically, when obtaining the center of the defect pattern, firstly, an ultrasonic C-scan image is acquired, the defect area is separated from the background, the defect pixel value is set to 1, and the background is 0, resulting in a binary image. Assuming the defect area is composed of multiple pixels, the coordinates of each pixel are recorded, and the arithmetic mean of all defect pixel coordinates is determined as the origin of the coordinates of the center of the irregular defect pattern.

[0057] In one specific embodiment, the transverse crack length is set to 5 mm, the width to 1 mm, the longest distance from the crack center to the farthest edge to R = 2.5 mm, and the area of ​​a single defect region to S = π × (2.5 mm)² = 19.6 mm².

[0058] Please see Figure 4 As shown, this is a logic diagram for determining whether a non-hidden defect area is a structurally damaged area according to an embodiment of the present invention. The process of determining whether a non-hidden defect area is a structurally damaged area by combining the area of ​​the overlapping defect area and the number of bubble defects corresponding to the overlapping defect area includes... If the area is greater than the area threshold and the number of bubble defects is greater than the number of bubble defects threshold, then the non-hidden defect area is determined to be a structurally damaged area. If the area is not greater than the area threshold or the number of bubble defects is not greater than the number of bubble defects threshold, then the non-hidden defect area is determined to be a non-structurally damaged area.

[0059] Specifically, the area threshold for overlapping defect regions and the number threshold for bubble defects both need to be dynamically determined based on the total surface area of ​​the cladding layer to be inspected. Therefore, the formula for setting the area threshold is as follows: The formula for the threshold number of bubble defects is: Where S is the area of ​​the overlapping defect region in mm², A is the total surface area of ​​the cladding layer in mm², and N is the number of bubble defects. This is the area ratio coefficient, ranging from 1% to 3%, preferably 2%. The number density coefficient ranges from 0.01 particles / mm² to 0.05 particles / mm², with 0.02 particles / mm² being the preferred value.

[0060] Specifically, this invention identifies overlapping defect areas as hidden defect areas and directly determines them as structurally damaged areas. If there is a strong geometric correlation between the defects, such as small spacing and similar depth, it indicates the risk of crack connection and bubble instability. If the overlapping defect areas are identified as non-hidden defect areas, the area and number of bubble defects are used to determine whether they are structurally damaged areas. When the risk of direct series between defects is not high, it is necessary to assess whether they pose a threat as a cluster by weakening the effective load-bearing area of ​​the material or forming a complex stress disturbance zone. The aggregation of large areas or multiple bubbles, even without close interaction, will significantly reduce the overall stiffness and strength of the area. Taking into account both area and bubble density improves the requirements for screening damaged areas, thereby further improving the accuracy of the ultrasonic phased array scanning detection method for cladding layer defects.

[0061] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. An ultrasonic phased array scanning method for detecting defects in cladding layers, characterized in that, include: The cladding layer is subjected to ultrasonic phased scanning to obtain the reflected signal. Based on the echo amplitude and pulse width of the reflected signal, defect characterization parameters are generated to classify the defect types, which include transverse crack defects, bubble defects and vertical crack defects. Crack length and crack depth of the transverse crack defect closest to the bubble defect are collected to generate crack characterization parameters to determine the single defect region of the transverse crack defect. The maximum diameter and bubble depth of the bubble defect are collected to generate bubble characterization parameters. The maximum diameter and bubble depth of the transverse crack defect after the functionalized fluid is applied are obtained to generate simulated bubble characterization parameters. Based on the bubble characterization parameters and the simulated bubble characterization parameters, bubble deviation parameters are calculated. Based on the bubble deviation parameters and the crack characterization parameters, simulated crack characterization parameters are generated to determine the single defect region corresponding to the bubble defect. Based on the single defect region corresponding to different defects, the overlapping defect region is determined. The hidden feature parameters are generated based on the defect center spacing and defect depth difference of the overlapping defect region to determine whether the overlapping defect region is a hidden defect region. In response to the overlapping defect region being a hidden defect region, the hidden defect region is determined as a structurally damaged region. In response to the overlapping defect region being a non-hidden defect region, the area of ​​the overlapping defect region and the number of bubble defects corresponding to the overlapping defect region are combined to determine whether the non-hidden defect region is a structurally damaged region.

2. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 1, characterized in that, The process of generating defect characterization parameters based on the echo amplitude and pulse width of the reflected signal to classify defect types includes, The amplitude factor is determined by the ratio of the difference between the echo amplitude and the reference echo amplitude to the reference echo amplitude. The pulse factor is defined as the ratio of the difference between the pulse width and the reference pulse width to the reference pulse width. The weighted sum of the amplitude factor and the pulse factor is determined to be a defect characterization parameter.

3. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 2, characterized in that, The method of generating defect characterization parameters based on the echo amplitude and pulse width of the reflected signal to classify defect types, wherein, If the defect characterization parameter is less than or equal to the first defect characterization threshold, the defect type is determined to be a bubble defect. If the defect characterization parameter is greater than the first defect characterization threshold and less than the second defect characterization threshold, then the defect type is determined to be a vertical crack defect. If the defect characterization parameter is greater than or equal to the second defect characterization threshold, the defect type is determined to be a transverse crack defect.

4. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 3, characterized in that, The process of collecting the crack length and crack depth of the transverse crack defect closest to the bubble defect to generate crack characterization parameters includes: The ratio of the crack length to the reference crack length is determined as the length factor; The ratio of the crack depth to the reference crack depth is determined as the crack depth factor; The weighted sum of the length factor and the crack depth factor is determined to be a crack characterization parameter.

5. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 4, characterized in that, The process of collecting the maximum diameter and depth of bubble defects to generate bubble characterization parameters includes: The ratio of the maximum diameter to the reference maximum diameter is determined as the diameter factor; The ratio of the bubble depth to the reference bubble depth is determined as the pore depth factor; The weighted sum of the diameter factor and the pore depth factor is determined to be a bubble characterization parameter.

6. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 5, characterized in that, The process of obtaining the maximum diameter and bubble depth of the transverse crack defect after the functionalized fluid is applied to generate simulated bubble characterization parameters includes: The weighted sum of the diameter factor and pore depth factor of the transverse crack defect after the functionalized fluid is applied is determined as a characterization parameter for the simulated bubble. The ratio of the difference between the bubble characterization parameters and the simulated bubble characterization parameters is determined as the bubble deviation parameter.

7. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 6, characterized in that, The process of generating concealed feature parameters based on the defect center spacing and defect depth difference of the overlapping defect regions to determine whether the overlapping defect regions are concealed defect regions includes: The absolute value of the distance between the centers of any two defects is the defect distance, and the ratio of the mean of the defect distances to the maximum defect center distance is determined as the distance factor. The absolute value of the depth difference between any two defects is the defect depth difference, and the ratio of the mean of the depth differences of each defect to the maximum defect depth difference is the depth factor. The weighted sum of the spacing factor and the depth factor is determined to be the hidden feature parameter.

8. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 7, characterized in that, Whether the overlapping defect region is a hidden defect region is determined based on the hidden feature parameters. If the concealed feature parameter is less than or equal to the concealed feature threshold, then the overlapping defect region is determined to be a non-concealed defect region. If the hidden feature parameter is greater than the hidden feature threshold, then the overlapping defect region is determined to be a hidden defect region.

9. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 8, characterized in that, The process of determining the overlapping defect regions based on the single defect regions corresponding to different defects includes: Using the center of the crack as the origin and the longest distance from the center to the edge of the crack as the radius, we can divide the area into single defect regions corresponding to transverse crack defects and vertical crack defects respectively. The area covered by at least two single defect areas is identified as the overlapping defect area.

10. The ultrasonic phased array scanning method for detecting defects in the cladding layer according to claim 9, characterized in that, The process of determining whether the non-hidden defect area is a structurally damaged area by combining the area of ​​the overlapping defect area and the number of bubble defects corresponding to the overlapping defect area includes: If the area is greater than the area threshold and the number of bubble defects is greater than the number of bubble defects threshold, then the non-hidden defect area is determined to be a structurally damaged area.

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