Ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate

Abstract

The invention discloses an ultrasonic water immersion phased array flaw detection method for a 7B52 laminated aluminum alloy plate, and relates to the technical field of flaw detection of aluminum alloy plates. The invention aims to solve the problems of unstable detection parameters and inaccurate detection of a traditional flaw detection method for interlayer bonding defects in a laminated aluminum alloy plate and material defects of a single-layer plate. Aiming at aluminum alloy laminated plates with different thicknesses and layer numbers, equipment comparison is carried out on defective parts by using a contact method, and compared with a traditional flaw detection method, the stability of detection parameters and the accuracy of detection results can be effectively ensured. According to the ultrasonic water immersion phased array flaw detection method for the 7B52 laminated aluminum alloy plate, the 7B52 laminated aluminum alloy plate can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy plate flaw detection, and in particular to an ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plates. Background Art

[0002] 7B52 laminated aluminum alloy plates are mainly used in the field of military special vehicles and ships, and have the advantages of high specific strength and strong anti-bullet ability. At present, there is no special method for non-destructive testing of the internal quality of 7B52 laminated aluminum alloy plates produced in my country. GJB9614-2019 mainly uses the A-type pulse reflection method. The phased array detection equipment currently used by the research team has the advantages of high resolution, rapid detection, and clear images compared to handheld instruments.

[0003] However, at present, the flaw detection methods for interlayer bonding defects inside laminated aluminum alloy plates and material defects of single-layer plates have problems of unstable detection parameters and inaccurate detection. Therefore, in order to ensure the detection quality and efficiency, it is of great practical significance to establish a dedicated ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plates for interlayer bonding defects inside laminated aluminum alloy plates and material defects of single-layer plates. Summary of the invention

[0004] The purpose of the present invention is to solve the problems of unstable detection parameters and inaccurate detection in traditional methods for detecting interlayer bonding defects inside laminated aluminum alloy plates and material defects of single-layer plates, and to provide an ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plates.

[0005] An ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plates is performed in the following steps:

[0006] Step S1: Probe and comparison test block selection;

[0007] A water immersion phased array probe and two single crystal probes were selected as probes; a 7B52 laminate made with the same specifications and the same processing method was selected as a comparison test block;

[0008] Step S2: benchmark sensitivity debugging;

[0009] Place the probe on the detection platform, automatically calibrate verticality, and use the gain value of 80% of the primary interface amplitude of the detection platform as the reference sensitivity; record the sensitivity of the test block at different buried depths, and adjust the test blocks at different buried depths to make the defect wave reach 80% as the detection sensitivity; increase 6dB on the basis of the detection sensitivity as the scanning sensitivity, and then perform sensitivity adjustment;

[0010] Step S3: flaw detection process;

[0011] ① Select three depth positions of the upper surface, middle and bottom of the test block to calibrate the depth compensation (TCG) curve;

[0012] ② Move the probe scanning trolley to the workpiece to be inspected, tilt the probe into the water, adjust the A-axis and B-axis angles to zero degrees, and the Z-axis coordinate to the thickness of the workpiece to be inspected + 10mm, and calibrate verticality;

[0013] ③ When there is a difference in the sound transmission characteristics between the comparison test block and the product under test, make sound transmission correction;

[0014] ④ Bottom wave monitoring: according to the different thickness of the test pieces, set the sensitivity dB value of the bottom wave position of the TCG curve, so that the bottom wave amplitude is 80%, the monitoring gate covers the bottom wave, and the bottom wave C scan formed after scanning, if the amplitude is less than 40%, the product is unqualified;

[0015] ⑤ Select the interface wave and bottom wave in the corresponding gates respectively, and change the position of the A-scan gate according to the bottom wave value;

[0016] ⑥ Adjust the B repetition frequency value until the B scan phantom wave disappears and save the ultrasound plan;

[0017] ⑦Create a corresponding batch folder in the Nuscan software, select the currently set sensitivity plan, draw the scanning area model, and save the scanning plan;

[0018] ⑧ Turn on the water immersion phased array flaw detection equipment, and the probe moves according to the path of the scanning plan to complete the flaw detection of the test block;

[0019] Step S4: defect assessment;

[0020] If a defect is found in the C scan, check the defect depth and enter the sensitivity dB value corresponding to the depth into the A scan window gain. Close the TCG curve and find the maximum reflection wave of the defect by moving / adjusting the probe position and angle to determine whether it is qualified.

[0021] Beneficial effects of the present invention:

[0022] The present invention uses the contact method to compare equipment at defective locations for aluminum alloy laminates of different thicknesses and numbers of layers. Compared with traditional flaw detection methods, the present invention can effectively ensure the stability of detection parameters and the accuracy of detection results.

[0023] The invention can obtain an ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plates. DETAILED DESCRIPTION

[0024] Specific implementation method 1: This implementation method is an ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate, which is carried out according to the following steps:

[0025] Step S1: Probe and comparison test block selection;

[0026] A water immersion phased array probe and two single crystal probes were selected as probes; a 7B52 laminate made with the same specifications and the same processing method was selected as a comparison test block;

[0027] Step S2: benchmark sensitivity debugging;

[0028] Place the probe on the detection platform, automatically calibrate verticality, and use the gain value of 80% of the primary interface amplitude of the detection platform as the reference sensitivity; record the sensitivity of the test block at different buried depths, and adjust the test blocks at different buried depths to make the defect wave reach 80% as the detection sensitivity; increase 6dB on the basis of the detection sensitivity as the scanning sensitivity, and then perform sensitivity adjustment;

[0029] Step S3: flaw detection process;

[0030] ① Select three depth positions of the upper surface, middle and bottom of the test block to calibrate the TCG curve;

[0031] ② Move the probe scanning trolley to the workpiece to be inspected, tilt the probe into the water, adjust the A-axis and B-axis angles to zero degrees, and the Z-axis coordinate to the thickness of the workpiece to be inspected + 10mm, and calibrate verticality;

[0032] ③ When there is a difference in the sound transmission characteristics between the comparison test block and the product under test, make sound transmission correction;

[0033] ④ Bottom wave monitoring: according to the different thickness of the test pieces, set the sensitivity dB value of the bottom wave position of the TCG curve, so that the bottom wave amplitude is 80%, the monitoring gate covers the bottom wave, and the bottom wave C scan formed after scanning, if the amplitude is less than 40%, the product is unqualified;

[0034] ⑤ Select the interface wave and bottom wave in the corresponding gates respectively, and change the position of the A-scan gate according to the bottom wave value;

[0035] ⑥ Adjust the B repetition frequency value until the B scan phantom wave disappears and save the ultrasound plan;

[0036] ⑦Create a corresponding batch folder in the Nuscan software, select the currently set sensitivity plan, draw the scanning area model, and save the scanning plan;

[0037] ⑧ Turn on the water immersion phased array flaw detection equipment, and the probe moves according to the path of the scanning plan to complete the flaw detection of the test block;

[0038] Step S4: defect assessment;

[0039] If a defect is found in the C scan, check the defect depth and enter the sensitivity dB value corresponding to the depth into the A scan window gain. Close the TCG curve and find the maximum reflection wave of the defect by moving / adjusting the probe position and angle to determine whether it is qualified.

[0040] Specific implementation method 2: The difference between this implementation method and specific implementation method 1 is that the water immersion phased array probe described in step S1 is a 10MHz-128elts water immersion phased array probe.

[0041] The other steps are the same as those in the first specific implementation.

[0042] Specific implementation method three: The difference between this implementation method and specific implementation method one or two is that the base material of the comparison test block described in step S1 is first subjected to non-destructive testing before processing, and the equivalent of the internal flat-bottom hole defect of the base material is less than 1.0 mm in diameter.

[0043] The other steps are the same as those in the first or second embodiment.

[0044] Specific implementation method 4: The difference between this implementation method and specific implementation methods 1 to 3 is that the ultrasonic incident surface of the comparison test block described in step S1 shall not be processed or ground, the roughness of the incident surface is ≤1.6μm, and the holes are cleaned, dried and sealed.

[0045] The other steps are the same as those in Specific Embodiments 1 to 3.

[0046] Specific implementation method five: The difference between this implementation method and specific implementation methods one to four is that the bottom surface processing depth of the comparison test block described in step S1 reaches the bonding area of ​​each layer of the laminate, which means that holes are punched perpendicular to the direction of the laminate to check whether there are processing defects in the bonding area of ​​each layer of the laminate.

[0047] The other steps are the same as those in Specific Embodiments 1 to 4.

[0048] Specific implementation method 6: The difference between this implementation method and specific implementation methods 1 to 5 is that: in step S2, the reference sensitivity is detected. If the amplitude of the reflection wave of the discontinuity defect is greater than 40%, a scan is performed near the defect position to obtain the maximum reflection wave of the discontinuity defect.

[0049] The other steps are the same as those in Specific Embodiments 1 to 5.

[0050] Specific implementation method seven: The difference between this implementation method and specific implementation methods one to six is ​​that: in step S2, the reference sensitivity is detected. When the noise signal is twice as large as the normal value, the surface condition of the product being inspected or the selection of the probe is checked to see if it is correct; after excluding influencing factors, if the noise is greater than the alarm level threshold, there is no need to perform ultrasonic testing.

[0051] The other steps are the same as those in Specific Embodiments 1 to 6.

[0052] Specific implementation example eight: This implementation example is different from specific implementation examples one to seven in that the coupling agent used is clean water.

[0053] The other steps are the same as those in Specific Embodiments 1 to 7.

[0054] The following examples are used to verify the beneficial effects of the present invention:

[0055] Example 1: An ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate is performed according to the following steps:

[0056] Step S1: probe selection;

[0057] A 10MHz-128elts immersion phased array probe and two single crystal probes were selected as probes;

[0058] The 10MHz-128elts water immersion phased array probe should meet the calibration specifications of ISO18563-2;

[0059] Step S2: test block selection;

[0060] Select different buried depths, diameters 75mm, Flat bottom hole aluminum alloy longitudinal wave comparison test block;

[0061] ① The comparison test block should be made of 7B52 laminated plates of the same specifications and the same processing method, and the surface should not have scratches, bumps, or other factors that may affect the test;

[0062] ② Before the comparison test block is processed, the parent material should be subjected to non-destructive testing, and no flat-bottom hole defects with an equivalent diameter greater than 1.0 mm should appear inside;

[0063] ③ The ultrasonic incident surface shall not be processed or ground, the incident surface roughness shall be ≤1.6μm, and the hole shall be clean, dry and sealed;

[0064] ④The bottom surface processing depth should reach the bonding area of ​​each layer of the laminate;

[0065] Step S3: benchmark sensitivity debugging;

[0066] The scanning sensitivity uses TCG curve technology. The flaw detection sensitivity should select an appropriate test block group according to the flaw detection level. For the A-level standard, the equivalent flat-bottom hole diameter is 2.0mm; for the B-level standard, the equivalent flat-bottom hole diameter is 3.2mm; place the probe on the detection platform, automatically calibrate verticality, and use the gain value of 80% of the first interface amplitude of the detection platform as the reference sensitivity. Record the sensitivity of the test blocks at different buried depths, adjust the test blocks at different buried depths so that the defect wave reaches 80% as the detection sensitivity, and increase 6db as the scanning sensitivity based on the detection sensitivity. In each detection, it is necessary to input the scanning sensitivity value of the appropriate test block thickness according to the plate of different thickness; because the curve can only input 16 points at most, that is, in each detection, it is necessary to input the scanning sensitivity value of the appropriate test block thickness according to the plate of different thickness;

[0067] Step S4: When the base sensitivity is detected, a recheck should be performed if one of the following two situations occurs:

[0068] ① When the amplitude of the reflection wave of the discontinuity defect is greater than 40%, a scan should be conducted near the defect location to obtain the maximum reflection wave of the discontinuity defect;

[0069] ② When the noise signal is twice as large as the normal value, the surface condition of the product being tested or the selection of the probe should be checked to see if it is correct; after eliminating the influencing factors, if the noise is greater than the alarm level threshold, ultrasonic testing should not be performed;

[0070] Step S5: operation process;

[0071] ① According to actual needs, select three depth positions of the upper surface, middle and bottom of the test block to calibrate the TCG curve;

[0072] ② Move the probe scanning trolley to the workpiece to be inspected, tilt the probe into the water, adjust the A and B axis angles to zero degrees, and the Z axis coordinate to the thickness of the workpiece to be inspected + 10mm, and calibrate verticality;

[0073] ③ When there is a difference in the sound transmission characteristics between the comparison test block and the product under test, make sound transmission correction;

[0074] ④ Bottom wave monitoring: according to the different thickness of the test pieces, set the sensitivity dB value of the bottom wave position of the TCG curve, so that the bottom wave amplitude is 80%, the monitoring gate covers the bottom wave, and the bottom wave C scan formed after scanning, if the amplitude is less than 40%, the product is unqualified;

[0075] ⑤ Select the interface wave and bottom wave in the corresponding gates respectively, and change the position of the A-scan gate according to the bottom wave value;

[0076] ⑥ Adjust the B repetition frequency until the B scan phantom wave disappears and save the ultrasound plan;

[0077] ⑦Create a corresponding batch folder in the Nuscan software, select the currently set sensitivity plan, draw the scanning area model, and save the scanning plan;

[0078] ⑧ Turn on the water immersion phased array flaw detection equipment, and the probe moves according to the path of the scanning plan to complete the flaw detection of the test block.

[0079] Step S6: defect assessment;

[0080] If a defect is found in the C scan, check the defect depth, enter the sensitivity dB value corresponding to the depth into the A scan window gain, close the TCG curve, find the maximum reflection wave of the defect by moving / adjusting the probe position and angle, and determine whether it is qualified.

[0081] In this embodiment, the large-scale water immersion phased array flaw detection equipment used is GE's UTxx. Domestic equipment can also be used, but the domestic instruments must meet the following conditions: 1. The comprehensive test of the equipment must meet ASTM E317; 2. The equipment board test must meet ISO 18563-1; 3. The mechanical accuracy of the equipment should be as consistent as possible with the original value of the manufacturer.

[0082] The coupling agent used in this embodiment is clean water.

[0083] The implementation standard of this embodiment is based on GJB 9614-2019 "7B52 Laminated Armor Aluminum Alloy Plate Specification" - Appendix A and customer agreement.

[0084] The static comparison test block used in the phased array detection of this embodiment should meet the requirements of ASTM E217. Newly purchased standard test blocks should be identified by a metrological verification agency and have an identification certificate issued. Every quarter, the appearance of the standard test blocks should be checked for surface damage that affects their use. If there is damage, they should be sent to an identification agency for identification and can only be used after passing the inspection. The test blocks should be sent to a verification agency for verification every 5 years, and their ultrasonic response should be checked and compared with the original data every 12 months. If there is any difference, they should be sent to a verification agency for verification.

Claims

1. An ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate, characterized in that The flaw detection method is carried out in the following steps: Step S1: Probe and comparison test block selection; A water immersion phased array probe and two single crystal probes were selected as probes; a 7B52 laminate made with the same specifications and the same processing method was selected as a comparison test block; Step S2: benchmark sensitivity debugging; Place the probe on the detection platform, automatically calibrate verticality, and use the gain value of 80% of the primary interface amplitude of the detection platform as the reference sensitivity; record the sensitivity of the test block at different buried depths, and adjust the test blocks at different buried depths to make the defect wave reach 80% as the detection sensitivity; increase 6dB on the basis of the detection sensitivity as the scanning sensitivity, and then perform sensitivity adjustment; Step S3: flaw detection process; ① Select three depth positions of the upper surface, middle and bottom of the test block to calibrate the TCG curve; ② Move the probe scanning trolley to the workpiece to be inspected, tilt the probe into the water, adjust the A-axis and B-axis angles to zero degrees, and the Z-axis coordinate to the thickness of the workpiece to be inspected + 10mm, and calibrate verticality; ③ When there is a difference in the sound transmission characteristics between the comparison test block and the product under test, make sound transmission correction; ④ Bottom wave monitoring: according to the different thickness of the test pieces, set the sensitivity dB value of the bottom wave position of the TCG curve, so that the bottom wave amplitude is 80%, the monitoring gate covers the bottom wave, and the bottom wave C scan formed after scanning, if the amplitude is less than 40%, the product is unqualified; ⑤ Select the interface wave and bottom wave in the corresponding gates respectively, and change the position of the A-scan gate according to the bottom wave value; ⑥ Adjust the B repetition frequency value until the B scan phantom wave disappears and save the ultrasound plan; ⑦Create a corresponding batch folder in the Nuscan software, select the currently set sensitivity plan, draw the scanning area model, and save the scanning plan; ⑧ Turn on the water immersion phased array flaw detection equipment, and the probe moves according to the path of the scanning plan to complete the flaw detection of the test block; Step S4: defect assessment; If a defect is found in the C scan, check the defect depth and enter the sensitivity dB value corresponding to the depth into the A scan window gain. Close the TCG curve and find the maximum reflection wave of the defect by moving / adjusting the probe position and angle to determine whether it is qualified.

2. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate according to claim 1 is characterized in that The water immersion phased array probe described in step S1 is a 10MHz-128elts water immersion phased array probe.

3. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy sheet according to claim 1 is characterized in that The base material of the comparison test block described in step S1 is first subjected to nondestructive testing before processing, and the equivalent of the internal flat-bottom hole defect of the base material is less than 1.0 mm in diameter.

4. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy sheet according to claim 1 is characterized in that The ultrasonic incident surface of the comparison test block described in step S1 shall not be processed or ground, the roughness of the incident surface is ≤1.6μm, and the holes are cleaned, dried and sealed.

5. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate according to claim 1 is characterized in that The bottom surface of the comparison test block described in step S1 is processed to a depth reaching the bonding area of ​​each layer of the laminate.

6. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy plate according to claim 1 is characterized in that In step S2, the reference sensitivity is detected. If the amplitude of the reflection wave of the discontinuity defect is greater than 40%, a scan is performed near the defect position to obtain the maximum reflection wave of the discontinuity defect.

7. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy sheet according to claim 1 is characterized in that In step S2, the reference sensitivity is detected. When the noise signal is twice as large as the normal value, the surface condition of the product under test or the selection of the probe is checked to see if it is correct. After eliminating the influencing factors, if the noise is greater than the alarm level threshold, ultrasonic testing is not required.

8. The ultrasonic water immersion phased array flaw detection method for 7B52 laminated aluminum alloy sheet according to claim 1 is characterized in that The coupling agent used is clean water.