Contrast test block and design method

Abstract

Provided is a contrast test block design method, comprising the following steps: determining the fillet radius and thickness of a fillet section according to the size of the fillet on the object to be detected; determining the inner and outer diameters of a first hollow cylindrical section and a second hollow cylindrical section which are respectively tangent to the fillet section perpendicularly and horizontally; determining the inner arc length and outer arc length of the fillet section; setting a plurality of flat-bottomed holes in the fillet section, setting the openings of the flat-bottomed holes on the outer arc edge of the fillet section, setting the axis to coincide with the line connecting the fillet center and the opening, and setting the hole bottom surface to be perpendicular to the axis; determining the minimum depth, diameter and maximum spacing of the flat-bottomed holes according to the surface resolution, detection sensitivity and effective sound beam width; setting part of the flat-bottomed holes to be arranged along the inner or outer arc edge direction of the fillet section and / or setting part of the flat-bottomed holes to be arranged along the circumferential direction, and setting part of the flat-bottomed holes to have different depths. The method can design a contrast test block with a fillet structure. Also provided is a contrast test block.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic testing, and more specifically to the field of ultrasonic testing comparison blocks. Background Technology

[0002] Ultrasonic testing is an effective method for detecting internal defects in metal forgings. For example, longitudinal waves are used to inspect billets, forgings, extruded and rolled parts, various connectors and composite materials, while transverse waves are used to inspect welds, pipes and bars.

[0003] In ultrasonic testing, reference standards are used to determine ultrasonic testing sensitivity and verify the effectiveness of the testing plan. Reference standards are samples with known, fixed characteristics, such as artificial reflectors with simple geometric shapes or simulating defects. They typically have specified materials, surface conditions, geometry, and dimensions. They can be used for ultrasonic testing equipment setup and calibration, defect assessment, etc., serving the same function as the part being tested.

[0004] Metal forgings with rounded structures have advantages such as saving material and improving heat treatment hardenability. Rounded structures generally have a first curvature along the rounding direction and a second curvature along the circumference direction. Under the interference of these two curvatures, ultrasonic waves are more easily dispersed upon incident.

[0005] Currently, for special forgings with rounded structures, contour scanning is generally required, where longitudinal waves are incident perpendicularly into the forging. However, due to the different incident surfaces, the reflection of the sound beam by the curved surfaces in the rounded structure differs from that of a flat surface. This can lead to significant discrepancies between the test results and the actual situation, resulting in lower detection sensitivity and poorer accuracy in defect evaluation. Furthermore, the rounded corner surface cannot be compared with a flat-bottomed hole test block incident on a flat surface. In actual contour scanning operations, under the premise of a rounded structure, effective echoes cannot be obtained after angle deflection steps. Therefore, the detection range may not cover the far-field region of the rounded structure, leading to missed detections.

[0006] Based on the above introduction, it is necessary to propose an ultrasonic testing comparison block to assist ultrasonic testing with a rounded structure, ensuring the accessibility and accuracy of the test. Summary of the Invention

[0007] One objective of this invention is to provide a comparative test block design method that can design a comparative test block suitable for rounded structures with two curvatures, effectively assisting in the ultrasonic testing of rounded structures.

[0008] The comparative test block design method for achieving the above objectives is used to design a comparative test block for comparison with the test piece in ultrasonic testing. The test piece has a rounded structure, and the rounding center, detection sensitivity, effective beam width, and surface resolution of the ultrasonic testing system have been determined.

[0009] The method includes the following steps: S1. Determine the rounding radius and rounding thickness of the rounding segment of the comparison test block according to the rounding dimensions on the test piece; S2. Determine the inner and outer diameters of the first and second hollow cylindrical segments, which are respectively perpendicularly and horizontally tangentially connected to the rounding segment, according to the rounding radius and the rounding thickness; S3. Determine the inner arc length of the inner arc edge and the outer arc length of the outer arc edge of the rounding segment according to the rounding radius, the rounding thickness, the first hollow cylindrical segment, and the second hollow cylindrical segment; S4. Set multiple flat-bottomed holes in the rounding segment, set the opening of the flat-bottomed holes on the outer arc edge of the rounding segment, set the axis of the flat-bottomed holes to coincide with the line connecting the center of the rounding circle and the opening, and set the bottom surface of the flat-bottomed holes to be perpendicular to the axis; S5. Determine the minimum burial depth of the flat-bottomed holes according to the surface resolution, determine the diameter of the flat-bottomed holes according to the detection sensitivity, and determine the maximum spacing of the flat-bottomed holes according to the effective sound beam width.

[0010] In one or more embodiments, the method further includes: S6. configuring a portion of the flat-bottomed holes along the inner or outer arc of the rounded segment and / or configuring a portion of the flat-bottomed holes along the circumferential direction of the rounded segment, and configuring a portion of the flat-bottomed holes to have different burial depths.

[0011] In one or more embodiments, the burial depth range of the flat-bottomed hole is set between the rounding thickness and the minimum burial depth.

[0012] In one or more embodiments, the rounding thickness is less than or equal to the actual rounding thickness of the part to be tested.

[0013] Another object of the present invention is to provide a comparative test block using the above-described comparative test block design method. The comparative test block includes: a first hollow cylindrical segment; a second hollow cylindrical segment; a rounded segment tangentially connected to the first hollow cylindrical segment and the second hollow cylindrical segment, including an outer arc edge and an inner arc edge; and a plurality of flat-bottomed holes circumferentially and / or arcuately disposed on the rounded segment. The openings of the flat-bottomed holes are located on the outer arc edge, the axis of the flat-bottomed holes coincides with the line connecting the center of the rounded segment and the opening, the bottom surface of the flat-bottomed holes is perpendicular to the axis, and at least some of the flat-bottomed holes have different burial depths.

[0014] In one or more embodiments, the comparative test block includes a first set of flat-bottomed holes, wherein the first set of flat-bottomed holes comprises a plurality of flat-bottomed holes that are equally spaced along the outer arc edge or the inner arc edge and have a first burial depth, the first burial depth being equal to the maximum burial depth.

[0015] In one or more embodiments, the comparative test block includes a second set of flat-bottomed holes, the second set of flat-bottomed holes comprising a plurality of flat-bottomed holes distributed at equal intervals along the outer arc edge or the inner arc edge, having a second burial depth equal to the minimum burial depth.

[0016] In one or more embodiments, the comparative test block includes a third set of flat-bottomed holes, wherein the third set of flat-bottomed holes comprises a plurality of flat-bottomed holes that are equally spaced along the circumference of the rounded section and have different burial depths.

[0017] In one or more embodiments, the comparative test block further includes a fourth set of flat-bottomed holes, wherein the diameter of the plurality of flat-bottomed holes in the fourth set of flat-bottomed holes is smaller than the diameter of the flat-bottomed holes determined according to the ultrasonic testing sensitivity.

[0018] In one or more embodiments, some of the flat-bottomed holes are stepped holes.

[0019] In one or more embodiments, the material of the comparison test block is the same as or has similar acoustic attenuation characteristics as the material of the test piece.

[0020] The above-mentioned comparative test block design method can design a rounded segment that can simultaneously have rounded curvature and circumferential curvature. The comparative test block with the above-mentioned rounded segment can more closely resemble the characteristics of the workpiece under inspection, realize the comparison of the rounded structure, and ensure the feasibility of ultrasonic testing of the structure.

[0021] Furthermore, the diameter, spacing, and burial depth range of the flat-bottomed hole are designed based on ultrasonic testing sensitivity, effective beam width, and surface resolution. This allows the flat-bottomed hole to serve as an artificial defect reference, enabling the verification and adjustment of testing parameters such as beam incident angle and scanning spacing. This ensures the accuracy and effectiveness of the testing parameters, thereby improving the accuracy and effectiveness of subsequent ultrasonic testing practices.

[0022] Furthermore, by comparing the scanning results of the comparison test block with the scanning results of the test piece, the defects can be evaluated, and the defect equivalent size can be obtained, thereby improving the accuracy of defect equivalent evaluation and improving the quality of ultrasonic testing. Attached Figure Description

[0023] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0024] Figure 1 This is a front view of one embodiment of the comparative test block.

[0025] Figure 2 This is an example of a comparative test block along... Figure 1 A cross-sectional view along the AA direction.

[0026] Figure 3 yes Figure 2A magnified view of point N in the middle.

[0027] Figure 4 This is a schematic diagram of one embodiment of the second set of flat-bottomed holes.

[0028] Figure 5 This is a schematic diagram of one embodiment of the third set of flat-bottomed holes.

[0029] Figure 6 It is along Figure 1 A top view of a cross section along the BB direction.

[0030] Figure 7 This is a flowchart of the comparative test block design method.

[0031] Explanation of reference numerals in the attached figures

[0032] 10. Comparison test block

[0033] 11. First hollow cylindrical section

[0034] 12. Second hollow cylindrical section

[0035] 13. Rounded section

[0036] 15. First hollow cavity

[0037] 16. Second hollow cavity

[0038] 40. Flat-bottomed hole

[0039] 41. Bottom surface of the hole

[0040] 42. Opening

[0041] 410. First set of flat-bottomed holes

[0042] 420. Second set of flat-bottomed holes

[0043] 430. Third set of flat-bottomed holes

[0044] 60. Inner arc edge

[0045] 70. Outer curved edge Detailed Implementation

[0046] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description to provide a full understanding of the invention. However, the invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual applications without departing from the spirit of the invention. Therefore, the scope of protection of the invention should not be limited by the content of these specific embodiments. It should be noted that these and subsequent accompanying drawings are merely examples and are not drawn to scale, and should not be construed as limiting the actual scope of protection claimed by the invention.

[0047] Ultrasonic testing is a technique that uses the interaction between ultrasonic waves and workpieces to study the reflected, transmitted, and scattered waves. It is used to detect macroscopic defects, measure geometric characteristics, detect and characterize changes in microstructure and mechanical properties of workpieces, and further evaluate their specific applications.

[0048] For test pieces with rounded structures, the two curvatures produced by the rounded structure make the propagation law of the sound beam more complex. Therefore, it is necessary to design a special comparison test block to improve the feasibility of ultrasonic testing for rounded parts.

[0049] A reference block is a test block used when inspecting a specific workpiece using a specific method. It is designed as an artificial reflector, such as a flat-bottomed hole or groove. Therefore, as a meaningful reference reflector, the reference block, by being set to have similar acoustic characteristics and dimensions to the workpiece under test, and by comparing the test signal received from the reference block with the test signal received from the workpiece under test, enables the calibration of ultrasonic testing, the adjustment of the ultrasonic testing equipment's status, or the evaluation of the equivalent size of defects.

[0050] Based on the above principles, this disclosure proposes a comparative test block design method, which designs the comparative test block based on the test piece with a rounded structure.

[0051] The following is combined Figure 7 The flowchart shown illustrates the method. Prior to the design, the rounding center O of the detection system, the detection sensitivity, the effective beamwidth, and the surface resolution were determined.

[0052] It should be noted that the above testing parameters are only used for the design of the comparison test block and are not completely consistent with the data used by the testing system when testing the test piece.

[0053] For ease of understanding, see appendix Figure 1 To be continued Figure 6 A coordinate system is provided to describe the orientational relationships, with the Z-axis representing the axial direction of the test block and the direction perpendicular to the Z-axis representing the radial direction. Furthermore, it should be noted that specific terms will be used in the following description to describe embodiments of this application, such as "an embodiment," "an embodiment," and / or "some embodiments," which refer to a particular feature, structure, or characteristic related to at least one embodiment of this application. It should be emphasized and noted that "an embodiment," "an embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this application can be appropriately combined.

[0054] Reference Figure 7The method first performs steps S1-S3 to determine the size of the comparison test block. The structure of the comparison test block 10 is then combined... Figures 1 to 6 understand.

[0055] Based on the rounding dimensions of the test piece, the rounding radius R and rounding thickness H of the rounding segment 13 of the comparison test block 10 are first determined. The rounding radius R and rounding thickness H are determined by the size of the test piece, and the rounding radius R and rounding thickness H of the rounding segment 13 are determined according to the rounding structure on the test piece of different sizes.

[0056] In one embodiment, the rounding thickness H is less than or equal to the actual rounding thickness of the part under test. That is, the rounding thickness H can be exactly the same as the actual rounding thickness of the part under test to fully restore the dimensions of the part under test. However, in another embodiment, when the actual rounding thickness of the part under test is too thick and needs to be measured simultaneously in both the inner and outer directions to cover the entire internal area of ​​the rounded segment structure, the rounding thickness H can also be less than the actual rounding thickness of the part under test. Only the detection parameters of a portion of the internal area of ​​the rounded structure are verified. In this case, only the rounding radius R and the outer arc length of the outer arc edge 60 formed therefrom are required to be consistent with the part under test.

[0057] In step S2, the inner and outer diameters of the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12, which are respectively perpendicular and horizontally tangential to the rounded segment 13, are determined based on the rounding radius R and the rounding thickness H.

[0058] The height of the first hollow cylindrical segment 11 on the Z-axis and the extension length of the second hollow cylindrical segment 12 on the XY plane are determined according to actual needs. This method does not limit them. As long as the volume size can meet the ultrasonic detection range, it can be applied to this disclosure.

[0059] In step S3, the inner arc length L1 of the inner arc edge 60 and the outer arc length L2 of the outer arc edge 70 of the rounded segment 13 are determined based on the rounding radius R, the rounding thickness H, the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12.

[0060] Specifically, after determining the fillet radius R and fillet thickness H, based on the characteristic that the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12 are tangent to the fillet segment 13, the inner arc length L1 and the outer arc length L2 of the fillet can be calculated. The formula for calculating the inner arc length L1 is as follows: The formula for calculating the outer arc length L2 of the fillet is:

[0061] The comparative test block designed using the above steps can be used as a reference. Figures 1 to 4Understanding is that the annular rounded segment 13 is tangentially connected to the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12. The inner arc edge 60 and the outer arc edge 70 give the rounded segment 13 a first curvature A1, while the circumferential structure tangent to the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12 gives the rounded segment 13 a second curvature A2. The rounded segment 13 includes an inner arc edge 60 and an outer arc edge 70. The length of the inner arc edge 60 is the inner arc length L1 of the rounded segment 13, and the length of the outer arc edge 70 is the outer arc length L2 of the rounded segment 13.

[0062] Specifically, the first hollow cylindrical segment 11 and the rounded segment 13 are connected perpendicularly and tangentially in the Z-axis direction. The first hollow cylindrical segment 11 includes a first hollow cavity 15, and the outer circumferential surface of the first hollow cylindrical segment 11 is tangential to the rounded segment 13. Figure 4 Point T3, as shown, has its inner circumferential surface tangent to the rounded segment 13. Figure 3 Point T1 is shown.

[0063] The second hollow cylindrical segment 12 and the rounded segment 13 are horizontally and tangentially connected in the XY plane. The second hollow cylindrical segment 12 includes an expanded second hollow cavity 16, which communicates with the first hollow cavity 15. The outer circumferential surface of the second hollow cylindrical segment 12 is tangential to the rounded segment 13. Figure 4 Point T4, as shown, has its inner circumferential surface tangent to the rounded segment 13. Figure 3 Point T2 is shown. Thus, the rounded segment 13 is tangentially connected to the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12.

[0064] Continuing with step S4, multiple flat-bottomed holes 40 are formed on the rounded section 13. The openings 42 of the flat-bottomed holes 40 are positioned on the outer arc edge 70 of the rounded section 13. The axis of the flat-bottomed holes 40 is aligned with the line connecting the center O of the rounded section and the opening 42. Each connecting line represents the radial direction centered on the center O of the rounded section. The bottom surface 41 of the flat-bottomed holes 40 is positioned perpendicular to the axis. Since the ultrasonic incident direction is consistent with the radial direction of the center O of the rounded section, the bottom surface 41 of the flat-bottomed holes 40 serves as an artificial reflector to reflect ultrasonic waves.

[0065] The ultrasonic waves used in the detection system of this disclosure are longitudinal waves, incident perpendicularly. The line connecting the center O of the rounded circle to the bottom surface 41 of each hole is consistent with the direction of ultrasonic wave incident, that is, the direction of ultrasonic wave incident is consistent with the radial direction from which the center O of the rounded circle begins. The detection sensitivity, effective beamwidth, and surface resolution are determined by the detection requirements.

[0066] Ultrasonic testing sensitivity refers to the ability of the entire ultrasonic testing system to detect even the smallest defects. The smaller the defect detected, the higher the ultrasonic testing sensitivity. The testing sensitivity is determined based on the testing requirements, which in turn determines the minimum diameter of the defect to be detected.

[0067] The effective beamwidth is related to the ultrasonic resolution, and together with the scanning step / spacing, it determines the coverage of the scan, thus determining the range of the scanning spacing t. When some flat-bottomed holes are not identified after the probe scans a group of holes, it indicates that the detection parameters are insufficient to cover the entire range, easily leading to the risk of missed detections. Therefore, the effective beamwidth needs to be adjusted.

[0068] Surface resolution is used to determine the minimum distance between a detection system and the incident surface of a workpiece that a defect can distinguish. Surface resolution is related to various factors such as the probe and the surface roughness of the workpiece. Surface resolution can determine the shallowest defect that the probe can detect.

[0069] Continue to step S5, determine the minimum burial depth d of the flat-bottomed hole 40 based on the surface resolution described above, determine the diameter of the flat-bottomed hole 40 based on the detection sensitivity, and determine the maximum spacing of the flat-bottomed hole 40 based on the effective sound beam width.

[0070] Specifically, the diameter of some flat-bottomed holes is determined based on the ultrasonic testing sensitivity, such as the diameter of a 40mm flat-bottomed hole. Setting it to 0.8mm indicates the minimum diameter of the defect to be detected.

[0071] The maximum spacing between adjacent flat-bottomed holes 40 along the arc length of the hole bottom surface 41 is determined based on the effective sound beam width. The maximum spacing also represents the maximum scanning step or the maximum scanning spacing. The value of the maximum scanning step or the maximum scanning spacing is a certain proportion of the effective sound beam width.

[0072] For example, the spacing can be set to 75% or 50% of the effective beam width. Since the scanning step or spacing, along with the effective beam width, affects the scanning range, a larger scanning step or spacing results in less sound velocity overlap, which can easily reduce the beam's coverage area and increase the risk of missed detections. However, considering detection efficiency, the scanning step or spacing cannot be set too small; otherwise, the effective area per scan will be too small, leading to excessively low detection efficiency.

[0073] Therefore, if reducing the scanning step / spacing fails to obtain echoes from all flat-bottomed holes with the same spacing, it indicates poor beam coverage and a missed detection area within the effective beam width. Thus, it is necessary to increase the effective beam width as the detection parameter to ensure that all parts of the rounded section can be covered by the ultrasonic detection scanning range.

[0074] The minimum embedment depth d of the flat-bottomed hole 40 is determined based on surface resolution. The distance from the bottom surface 41 of the hole to the inner arc edge 60 is called the embedment depth, which is the difference between the rounding thickness H and the hole depth c of the flat-bottomed hole 40. Based on surface resolution, the hole depth c of the flat-bottomed hole 40 cannot exceed the difference between H and d; otherwise, the embedment depth will be too shallow, and the detection system will not be able to properly distinguish defects. The minimum embedment depth d varies depending on the detection equipment; for example, in one embodiment, the minimum embedment depth d is approximately 5 mm or 6 mm. The embedment depth range of the flat-bottomed hole 40 is set between the rounding thickness H and the minimum embedment depth d.

[0075] Furthermore, in one embodiment, due to limitations in the drilling equipment and drilling operation, the hole depth c has a minimum value c0, meaning the depth of the flat-bottomed hole 40 must be greater than c0. The minimum value c0 varies depending on the test block, such as approximately 6–10 mm in one embodiment. In this case, the embedment depth range of the flat-bottomed hole 40 is set between the difference between the rounding thickness H and the minimum value c0 and the minimum embedment depth d.

[0076] By using the aforementioned comparative test block design method, a rounded segment with two types of curvature can be designed. Furthermore, by setting multiple flat-bottomed holes, these holes can serve as artificial defect references, allowing for the verification and adjustment of detection parameters such as the sound beam incident angle and scanning interval. This ensures the accuracy and effectiveness of the detection parameters, thereby improving the accuracy and effectiveness of subsequent ultrasonic testing practices. Additionally, by comparing the scanning results of the flat-bottomed holes in the comparative test block with the scanning results of the part under test, defects can be evaluated, and the defect equivalent size can be determined, thus improving the accuracy of defect equivalent evaluation and enhancing the quality of ultrasonic testing.

[0077] Furthermore, in one embodiment, the method further includes step S6, setting some flat-bottomed holes to be arranged arc-shaped along the inner arc edge 60 or outer arc edge 70 of the rounded segment 13, and / or setting some flat-bottomed holes to be arranged circumferentially along the circumferential direction of the rounded segment 13, and setting some flat-bottomed holes 40 to have different burial depths.

[0078] Such as combination Figure 6 As shown, the flat-bottomed holes include a first group of flat-bottomed holes 410 and a second group of flat-bottomed holes 420 distributed arcwise along the first arc A1 direction, and a third group of flat-bottomed holes 430 distributed circumferentially along the second arc A2 direction. Different distributions of flat-bottomed holes are designed to meet different testing requirements.

[0079] For example, the third set of flat-bottomed holes 430 distributed circumferentially can be used to plot DAC or TCG curves, while the first set of flat-bottomed holes 410 and the second set of flat-bottomed holes 420 distributed arcuately can be used to verify far-field divergence and adjust the incident angle of the sound beam. This verification will be described in detail later.

[0080] Based on the above introduction to the design method of the comparison test block, we can also understand a comparison test block designed using this method, which is used for comparative testing in ultrasonic detection.

[0081] Combination Figure 1 and Figure 2 As shown, the comparative test block includes a first hollow cylindrical section 11, a second hollow cylindrical section 12, a rounded section 13, and multiple flat-bottomed holes. The outer diameter of the second hollow cylindrical section 12 is larger than the outer diameter of the first hollow cylindrical section 11. The first hollow cylindrical section 11 has a first hollow cavity 15, and the second hollow cylindrical section 12 has a second hollow cavity 16. The first hollow cavity 15 and the second hollow cavity 16 are connected to each other.

[0082] The rounded section 13 is tangentially connected to the first hollow cylindrical section 11 and the second hollow cylindrical section 12, and includes an outer arc edge 70 and an inner arc edge 60. Multiple flat-bottomed holes 40 are provided on the rounded section 13. The opening 42 of the flat-bottomed holes 40 is located on the outer arc edge 70. The axis of the flat-bottomed holes 40 coincides with the line connecting the center O of the rounded section and the opening 42. The bottom surface 41 of the flat-bottomed holes 40 is perpendicular to the axis. At least some of the flat-bottomed holes 40 have different embedment depths.

[0083] By setting the bottom surface 41 of the flat-bottomed hole to be perpendicular to the axis, i.e., perpendicular to the direction of ultrasonic wave incident, the bottom surface 41 of the hole can act as an artificial reflector to reflect ultrasonic waves. When the acoustic pulse propagates in the comparison test block, part of the wave will be reflected when it encounters the bottom surface 41 of the hole. Based on the presence or absence of the reflected wave, its intensity, and the time interval between the reflected wave and the emitted pulse, the size and burial depth of the bottom surface 41 of the hole can be measured. This data can be used to compare the location of defects in the test piece.

[0084] In one embodiment, refer to Figure 3 As shown, the comparative test block includes a first group of flat-bottomed holes 410. The first group of flat-bottomed holes 410 contains multiple flat-bottomed holes 40 evenly distributed along the outer or inner arc edge, each with a first burial depth m1, which is equal to the maximum burial depth. The hole axis of the first group of flat-bottomed holes 410 is aligned with the ultrasonic wave incident direction, and the bottom surface 41 of the holes is perpendicular to the ultrasonic wave incident direction. Multiple flat-bottomed holes are arranged at equal intervals until they cover the entire fan-shaped area of ​​all rounded segments 13.

[0085] Setting the first burial depth m1 to the maximum burial depth is used to verify the far-field resolution of the sound beam. The sound beam is focused on the surface of the part and will diffuse in the far field. Simultaneously, as the sound path increases, the echo decreases. To achieve the same detection sensitivity, increasing the gain will be accompanied by increased clutter, leading to a decrease in detection capability. Therefore, the detection depth of ultrasound is limited; when the far-field location exceeds the lateral resolution of the detection system, poor detection results will occur.

[0086] The rounded structure with two curvatures exhibits structural divergence, meaning that the arc lengths of the near and far surfaces at the same angle differ significantly. When using a step-scan at a certain incident angle, the beam coverage of the near surface is much greater than that of the far surface. If 50% of the effective beam width is used as the incident surface scanning interval, the beam may not overlap and cover the far field due to structural divergence, potentially leading to missed defects. Therefore, to determine the far-field detection resolution of this structure, the first burial depth m1 of the multiple flat-bottomed holes 40 included in the first group of flat-bottomed holes 410 is set to the maximum burial depth, and the hole depth c should be as small as possible to create a far-field environment that meets the maximum detection depth requirement.

[0087] In this setup, the accuracy of the detection system in identifying the number of flat-bottomed holes in the first group of flat-bottomed holes 410 is analyzed using the first group as a reference, thus verifying the coverage of the monitoring system. When the detection system can accurately identify each flat-bottomed hole 40 included in the first group of flat-bottomed holes 410, it proves that the coverage of the detection system meets the detection requirements, and no missed detections will occur when inspecting the workpiece, ensuring the reliability of the detection.

[0088] If the detection system cannot distinguish the first group of flat-bottomed holes 410 well, the detection parameters can be adjusted by increasing the beam width to meet the coverage requirements.

[0089] In another embodiment, such as Figure 4 As shown, the comparative test block includes a second set of flat-bottomed holes 420. The second set of flat-bottomed holes 420 includes multiple flat-bottomed holes 40 that are evenly distributed along the outer arc edge 70 or the inner arc edge 60, and has a second burial depth m2, which is equal to the minimum burial depth d.

[0090] The smaller the sound path, the less the sound wave is affected by the scattering caused by the microstructure in the part under inspection. Therefore, the second set of flat-bottomed holes 420 with the minimum burial depth can ensure better echo reception effect and can be used to adjust the incident angle of the sound beam.

[0091] The incident angle of the sound beam represents the angle at which the ultrasonic wave strikes the bottom surface 41 of the aperture. The longitudinal wave emitted by the probe needs to strike the bottom surface 41 of the aperture perpendicularly. If the incident beam is not perpendicular, some of the waves reflected back from the flat-bottomed aperture surface will not be received by the probe, resulting in a reduced echo reception rate. If the incident beam is tilted to a certain extent, waveform conversion will occur, producing refracted longitudinal waves, transverse waves, etc. Therefore, the sound beam must be perpendicularly incident during the detection process.

[0092] Therefore, the second set of flat-bottomed holes 420 is used to adjust the incident angle of the sound beam, ensuring that the incident angle of the probe is perpendicular when inspecting the workpiece. Because the second set of flat-bottomed holes 420 has a smaller burial depth, it can achieve better echo effect. By moving the probe and partially rotating it during operation to change the incident direction of the sound beam, when the echo received by the instrument is at its highest, it is considered that the incident angle of the sound beam is perpendicular to the bottom surface 41 of the hole, and the incident angle of the probe meets the requirements, thus completing the adjustment of the incident angle of the sound beam.

[0093] In one embodiment, the comparative test block includes a third group of flat-bottomed holes 430, wherein the third group of flat-bottomed holes 430 comprises a plurality of flat-bottomed holes 40 evenly distributed along the circumferential direction of the rounded section 13, and having different burial depths. Figure 5 and Figure 6 understand, Figure 5 The positions of the bottom surfaces 41, 41', and 41" of the three holes are simply shown. The hole depth c of each flat-bottomed hole is different along the circumferential direction, resulting in different burial depths of each flat-bottomed hole, but all flat-bottomed holes are located in the same circumferential direction.

[0094] The third set of flat-bottomed holes 430 is used to plot DAC or TCG curves. The flat-bottomed holes 40 included in the third set of flat-bottomed holes 430 should have multiple embedment depths, preferably including the maximum and minimum embedment depths that the comparative test block can withstand.

[0095] The DAC curve (distance-amplitude curve) is a distance-amplitude curve. The horizontal axis represents the sound path, and the vertical axis represents the echo amplitude. The sound path can be considered as a representation of depth. Because sound waves attenuate as they propagate along the depth direction, even for flat-bottomed holes of the same size, the echo amplitude will vary depending on the sound path and depth. A smooth curve connecting the different amplitudes corresponding to different sound paths is called the DAC curve.

[0096] Because the echo amplitude of a defect of the same equivalent decreases exponentially with increasing depth due to signal attenuation, beam diffusion, and other factors, the reflected echo amplitude at different depths can form a DAC curve. The decreasing trend of this DAC curve along the depth direction is used to compensate for the reflected echo amplitude at different depths. The curve formed by connecting all the depth compensation values ​​is called the TCG curve.

[0097] In the plotting, the sound path of the sound beam incident on the flat-bottomed holes of different burial depths included in the third group of flat-bottomed holes 430 was recorded. When the echo amplitude of each flat-bottomed hole reached 80%, the detection sensitivity at different depths was obtained, and the DAC / TCG curves were obtained.

[0098] By setting a third set of flat-bottomed holes 430 with different burial depths, different sound paths and echo amplitudes can be obtained, and DAC curves can be plotted accordingly. Under this DAC curve, the detection sensitivity between the two burial depths can be determined by interpolation.

[0099] Since the DAC / TCG curves are different for each material, the comparison test block 10 is preferably made of the same material as the test piece and has the same heat treatment state and surface state as the test piece in order to plot accurate values.

[0100] In another embodiment, the comparative test block further includes a fourth set of flat-bottomed holes, wherein the diameter of the plurality of flat-bottomed holes 40 included in the fourth set of flat-bottomed holes is smaller than the diameter of the flat-bottomed holes determined according to the ultrasonic detection sensitivity.

[0101] In step S5, the diameter of the flat-bottom hole is determined by the ultrasonic testing sensitivity. However, other sizes smaller than the diameter of the flat-bottom hole can still be set. For example, if the diameter φ of the flat-bottom hole is determined to be 0.8 mm based on the smallest defect that the ultrasonic testing sensitivity can distinguish, then the diameter of the fourth set of flat-bottom holes can be selected as 0.6 or 0.4 mm or other sizes smaller than 0.8 mm to verify the limit of the resolution capability of the testing equipment.

[0102] The above embodiments are for reference only. In actual design, the specific diameter of the fourth set of flat-bottomed holes shall be determined by those skilled in the art based on the detection system and detection requirements, and shall not be limited to the size reduction limits mentioned in the above embodiments.

[0103] Furthermore, in one embodiment, some of the flat-bottomed holes 40 are stepped holes. For example, since the hole depth c of the second group of flat-bottomed holes 420 is larger and the second burial depth m2 is smaller, the second group of flat-bottomed holes 420 is preferably configured as stepped holes. Stepped holes, such as... Figure 4 As shown, a smaller aperture is provided on the side near the bottom surface 41 of the hole, and a larger aperture is provided on the side near the opening 42. The purpose of providing a stepped hole is to facilitate machining.

[0104] The aforementioned comparative test block design method, by setting multiple sets of flat-bottomed holes, enables the comparative test block to be used simultaneously to adjust the incident angle of the sound beam, verify the far-field dispersion of the sound beam, plot DAC or TCG curves, and detect the identification limit of the detection equipment, forming a reference reflector with clear significance, thereby evaluating the detection system and improving the accuracy of actual ultrasonic detection results.

[0105] The comparison test block is designed with reference to the dimensions of the workpiece under test. It can be used to verify the performance of ultrasonic instruments and probes, determine instrument sensitivity and adjust scanning speed, and determine the relative location and size of defects. Therefore, the comparison test block should be as consistent as possible with the acoustic characteristics of the workpiece being tested, preferably using the same material or a similar sound attenuation material to achieve a better comparison effect.

[0106] also, Figure 1 Compared to ordinary R-angle and folded corner structures, the comparative test block 10 shown can achieve a larger curvature, while also increasing the curvature from the annular circumferential direction.

[0107] specific Figure 1 As shown, the rounded segment 13 of the comparative test block 10 includes two curvatures: the first curvature A1 comes from the rounded structure, and the second curvature A2 comes from the annular circumferential connection structure of the first hollow cylindrical segment 11 and the second hollow cylindrical segment 12. Since the first curvature A1 and the second curvature A2 each significantly affect the incident and reflection effects of ultrasonic waves, increasing the complexity, this comparative test block can explore the incident and reflection of ultrasonic waves under two curvatures.

[0108] Furthermore, the rounded segment in the comparison test block more closely resembles the actual part being tested. When operating on curved structures, it is typically necessary to input the outer perimeter of the arc to provide the probe with an automatic travel path, enabling the detection system to perform contour scanning. If a test block with the same curvature distribution as the rounded structure of the actual part being tested is unavailable, the angle deflection step, detection speed, and beam width cannot be verified, thus affecting detection accuracy and potentially causing missed detections. Figure 1 The test block shown can be compared and analyzed to obtain suitable parameters for ultrasonic testing, ensuring the feasibility of ultrasonic testing on forgings with this rounded structure, and further improving the accuracy of actual ultrasonic testing.

[0109] It should be noted that, Figure 6 The symbols in the text are merely schematic representations of the positions of the holes and do not represent the actual cross-sectional shape of the flat-bottomed holes. The above description also uses terms such as "first," "second," and "third" to describe features. These qualifying terms are only for the purpose of distinguishing the corresponding features or components. Unless otherwise stated, these terms have no special meaning, do not indicate primary or secondary importance, and therefore should not be construed as limiting the scope of protection of this application.

[0110] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of range in some embodiments of this application are approximate values, in specific embodiments, such numerical values ​​are set as precisely as feasible.

[0111] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any variations and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the invention, fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for designing a comparative test block, used to design a comparative test block for comparison with a workpiece under test in ultrasonic testing, wherein the workpiece under test has a rounded structure, and the center of the rounded structure, detection sensitivity, effective beamwidth, and surface resolution of the ultrasonic testing system have been determined, characterized in that... Includes the following steps: S1. Determine the rounding radius and rounding thickness of the rounding segment (13) of the comparison test block (10) based on the rounding dimensions on the test piece; S2. Determine the inner and outer diameters of the first hollow cylindrical segment (11) and the second hollow cylindrical segment (12) that are perpendicularly and horizontally tangentially connected to the rounded segment (13) respectively, based on the rounded radius and the rounded thickness; S3. Determine the inner arc length of the inner arc edge (60) and the outer arc length of the outer arc edge (70) of the rounded segment (13) based on the rounded radius, the rounded thickness, the first hollow cylindrical segment (11) and the second hollow cylindrical segment (12); S4. A plurality of flat-bottomed holes (40) are provided in the rounded section (13), the opening (42) of the flat-bottomed hole (13) is set on the outer arc edge (70) of the rounded section (13), the axis of the flat-bottomed hole (13) is set to coincide with the line connecting the center of the rounded section and the opening (42), and the bottom surface (41) of the flat-bottomed hole (40) is set to be perpendicular to the axis. S5. Determine the minimum burial depth of the flat-bottomed hole (40) based on the surface resolution, determine the diameter of the flat-bottomed hole (40) based on the detection sensitivity, and determine the maximum spacing of the flat-bottomed hole (40) based on the effective sound beam width; S6. Part of the flat-bottomed holes (40) are configured along the direction of the inner arc edge (60) or outer arc edge (70) of the rounded segment (13) and / or part of the flat-bottomed holes (40) are configured along the circumferential direction of the rounded segment (13). Some of the flat-bottomed holes (40) are configured to have different burial depths.

2. The comparative test block design method as described in claim 1, characterized in that, The burial depth range of the flat-bottomed hole (40) is set between the rounding thickness and the minimum burial depth.

3. The comparative test block design method as described in claim 1, characterized in that, The rounding thickness is less than or equal to the actual rounding thickness of the part to be tested.

4. A comparative test block (10) for comparative testing in ultrasonic detection, characterized in that, The comparative test block design method as described in any one of claims 1-3 comprises: First hollow cylindrical segment (11); Second hollow cylindrical segment (12); The rounded segment (13), tangentially connected to the first hollow cylindrical segment (11) and the second hollow cylindrical segment (12), includes an outer arc edge (70) and an inner arc edge (60); and Multiple flat-bottomed holes (40) are arranged circumferentially and / or arcuately on the rounded section (13). The opening (42) of the flat-bottomed hole (40) is located on the outer arc edge (70). The axis of the flat-bottomed hole (40) coincides with the line connecting the center of the rounded section and the opening (42). The bottom surface (41) of the flat-bottomed hole (40) is perpendicular to the axis. At least some of the flat-bottomed holes (40) have different burial depths.

5. The comparative test block as described in claim 4, characterized in that, The comparative test block includes a first set of flat-bottomed holes (410), the first set of flat-bottomed holes (410) includes a plurality of flat-bottomed holes (40) that are equally spaced along the outer arc edge (70) or the inner arc edge (60) and have a first burial depth, the first burial depth being equal to the maximum burial depth.

6. The comparative test block as described in claim 4, characterized in that, The comparative test block includes a second set of flat-bottomed holes (420), the second set of flat-bottomed holes (420) includes a plurality of flat-bottomed holes (40) distributed at equal intervals along the outer arc edge (70) or the inner arc edge (60), having a second burial depth, the second burial depth being equal to the minimum burial depth.

7. The comparative test block as described in claim 4, characterized in that, The comparative test block includes a third set of flat-bottomed holes (430), which contains multiple flat-bottomed holes (40) that are evenly distributed circumferentially along the rounded section (13) and have different burial depths.

8. The comparative test block as described in claim 4, characterized in that, The comparative test block also includes a fourth set of flat-bottomed holes, wherein the diameter of the multiple flat-bottomed holes in the fourth set of flat-bottomed holes is smaller than the diameter of the flat-bottomed holes determined according to the ultrasonic testing sensitivity.

9. The comparative test block as described in claim 4, characterized in that, The flat-bottomed hole (40) described in part is a stepped hole.

10. The comparative test block as described in claim 4, characterized in that, The material of the comparison test block (10) is the same as or has similar acoustic attenuation characteristics as the material of the test piece.

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