Ultrasonic detection method for layering of multi-layer metal material explosive clad steel plate
By drilling flat bottom blind holes of series of apertures on the explosion composite steel plate of multi-layer metal material, a curve of relationship between echo signal amplitude and aperture is established, combined with depth information, the problem of low detection accuracy of small layered defects of multi-layer composite materials in the prior art is solved, and high-precision layered defect detection is achieved.
Patent Information
- Application Number
- CN202311644473.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-04
- Publication Date
- 2025-06-06
AI Technical Summary
The prior art is difficult to efficiently detect smaller stratification defects in multi-layer composite materials, especially in ultrasonic detection, and the lack of consideration of echo phase information of stratification defects leads to low detection accuracy.
By drilling flat bottom blind holes with series of apertures on the explosion composite steel plate of multi-layer metal material, the echo signal amplitude is obtained using ultrasonic detection instruments, and the relationship curve between the flat bottom blind hole aperture and the echo signal amplitude is established. Combined with the depth information of the echo signal, the size and depth of the layered defects are analyzed.
The identification of small layered defects of explosion composite steel plates of multi-layer metal materials is improved and the accuracy of dimensional measurement is achieved, and effective detection of smaller layered defects is achieved.
Smart Images
Figure CN120102722A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of ultrasonic detection, in particular to an ultrasonic detection method for delamination of multi-layer metal material explosive composite steel plates. Background Art
[0002] There are relevant national or industry testing standards or specifications for the pulse reflection ultrasonic testing method of composite materials, such as non-destructive testing of pressure equipment (NB / T47013.3-2015), aluminum alloy-aluminum-steel (stainless steel) composite transition joint specification (CB20091-2012) and other standards. Before the molding of various parts, the composite molded plate-shaped raw materials will be ultrasonically tested according to the relevant acceptance standards. The pulse reflection ultrasonic testing method has clear bonding rate requirements for unbonded areas. For example, if NB / T47013.3-2015 is used as the testing standard, when the bonding rate is 100%, the length of a single unbonded area less than 25mm will not be counted. The standard clarifies the determination method of the unbonded area, which is determined by referring to the relative value of the first bottom echo height and the unbonded defect echo height of the unbonded area boundary, but no measurement method is given for the delamination with an unbonded length less than 25mm. The above detection method uses the full-wave waveform display of A scan, and only obtains the echo amplitude and depth information, without considering the information of the phase of the delamination defect echo. The detection accuracy of smaller delamination defects is not high. A large number of studies and applications have shown that when the ultrasonic wave is incident vertically to the smooth plane interface, a reflected wave opposite to the incident direction will be generated in the first medium. The reflected wave is affected by the acoustic impedance of the two media, and the reflected wave and the incident wave will be superimposed in the same phase or in the opposite phase. If you want to identify smaller delamination defects in multilayer composite materials, you can achieve the detection purpose by analyzing the phase superposition and amplitude change of the reflected echo. Summary of the invention
[0003] The present invention provides an ultrasonic detection method for delamination of explosive composite steel plates of multi-layer metal materials, which overcomes the shortcomings of the above-mentioned prior art and can effectively solve the problem of lack of detection technology for smaller delamination defects of multi-layer composite materials in the prior art.
[0004] The technical solution of the present invention is achieved by the following measures: an ultrasonic detection method for delamination of multi-layer metal material explosion composite steel plate, which is carried out according to the following steps: S1, select a multi-layer metal material explosive composite steel plate with the same specifications and materials as the sample to be tested as a comparison test block, determine the scanning surface of the ultrasonic test and the punching surface of the flat-bottom blind hole, and drill holes from the punching surface of the flat-bottom blind hole and the target interface on the comparison test block to make flat-bottom blind holes with a series of apertures; S2, using an ultrasonic testing instrument to perform ultrasonic testing on flat-bottomed blind holes of a series of apertures on a scanning surface, obtaining the echo signal amplitude of the flat-bottomed blind holes on the target interface, and making a relationship curve between the aperture of the flat-bottomed blind holes and the corresponding echo signal amplitude; S3, testing the sample to be tested under the same ultrasonic testing conditions as in step S2, obtaining the amplitude of the delamination defect echo signal of the target interface of the sample to be tested, and then comparing the relationship curve between the amplitude of the delamination defect echo signal on the sample to be tested and the aperture of the flat-bottomed blind hole and the corresponding echo signal amplitude, to obtain the equivalent size of the delamination defect part of the sample to be tested, and comprehensively analyzing the size and depth of the delamination defect part in combination with the depth information of the echo signal.
[0005] The following are further optimizations and / or improvements to the above technical solutions: In the above step S1, the scanning surface of the ultrasonic detection is the outer side surface of the thicker layer of the outer metal layer of the multi-layer metal material explosive composite steel plate, and the punching surface of the flat-bottomed blind hole is the other outer side surface of the multi-layer metal material explosive composite steel plate.
[0006] In the above step S1, the bottom of the flat-bottomed blind hole is located on the target interface, and the distance from the punching surface of the flat-bottomed blind hole to the target interface is the depth of the flat-bottomed blind hole.
[0007] In the above step S1, the spacing between the flat-bottomed blind holes is 40 mm to 200 mm.
[0008] In the above step S1, the diameter of the flat-bottomed blind hole is 1 mm to 25 mm, and the number of the flat-bottomed blind holes of the series aperture is 5 to 15.
[0009] In the above step S2, the ultrasonic probe used for ultrasonic testing is a single crystal ultrasonic straight probe. The frequency and diameter of the single crystal ultrasonic straight probe are selected based on the following principles: the interface wave signals of the metal materials on both sides of the target interface can be accurately distinguished, and the target interface must be located outside the three times near field length of the ultrasonic probe sound field.
[0010] In the above step S2, the amplitude of the echo signal is represented by the gain value of the ultrasonic detection equipment under the same reference wave height.
[0011] The present invention proposes an accurate and feasible determination method for smaller delamination defects in multi-layer metal material explosion composite steel plates, and establishes an ultrasonic detection method for delamination of multi-layer metal material explosion composite steel plates using the amplitude and depth position characteristics of the defect signal, thereby improving the identifiability of small delamination defects in multi-layer metal material explosion composite steel plates and the accuracy of size measurement, and providing technical guidance for the optimization of ultrasonic detection schemes for multi-layer metal material explosion composite steel plates. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Attached Figure 1It is a schematic cross-sectional view of the multi-layer metal material explosion composite steel plate in the present invention.
[0013] Attached Figure 2 The wavy morphology of the interface of the multi-layer metal material explosion composite steel plate in the present invention.
[0014] Attached Figure 3 It is a schematic diagram of the full-wave form of the conventional ultrasonic detection echo signal in the present invention.
[0015] Attached Figure 4 It is a schematic diagram of the full-wave form of the interface wave signal in the present invention after being enlarged.
[0016] Attached Figure 5 It is a schematic diagram of the interface wave non-detection signal display (radio frequency signal) in the present invention.
[0017] Attached Figure 6 Schematic diagram of the flat-bottomed blind hole in Example 8 of the present invention.
[0018] Attached Figure 7 Schematic diagram of the comparison test block and flat-bottomed blind holes of a series of apertures in Example 8 of the present invention.
[0019] Attached Figure 8 This is a diagram of the echo signal of ultrasonic detection of the target interface in Example 8 of the present invention, where the arrow indicates the first wave peak.
[0020] Attached Fig. 9 This is a schematic diagram of the first wave peak (indicated by the arrow) of the target interface ultrasonic detection echo signal rising to 80% in Example 8 of the present invention.
[0021] Attached Fig.10 Graph showing the relationship between the aperture of the flat-bottomed blind hole and the amplitude of the corresponding echo signal in Example 8 of the present invention. DETAILED DESCRIPTION
[0022] The present invention is not limited by the following embodiments, and specific implementation methods can be determined based on the technical solution of the present invention and actual conditions.
[0023] The present invention will be further described below in conjunction with embodiments: Embodiment 1: The ultrasonic detection method for delamination of the multi-layer metal material explosion composite steel plate is carried out according to the following steps: S1, select a multi-layer metal material explosive composite steel plate with the same specifications and materials as the sample to be tested as a comparison test block, determine the scanning surface of the ultrasonic test and the punching surface of the flat-bottom blind hole, and drill holes from the punching surface of the flat-bottom blind hole and the target interface on the comparison test block to make flat-bottom blind holes with a series of apertures; S2, using an ultrasonic testing instrument to perform ultrasonic testing on flat-bottomed blind holes of a series of apertures on a scanning surface, obtaining the echo signal amplitude of the flat-bottomed blind holes on the target interface, and making a relationship curve between the aperture of the flat-bottomed blind holes and the corresponding echo signal amplitude; S3, testing the sample to be tested under the same ultrasonic testing conditions as in step S2, obtaining the amplitude of the delamination defect echo signal of the target interface of the sample to be tested, and then comparing the relationship curve between the amplitude of the delamination defect echo signal on the sample to be tested and the aperture of the flat-bottomed blind hole and the corresponding echo signal amplitude, to obtain the equivalent size of the delamination defect part of the sample to be tested, and comprehensively analyzing the size and depth of the delamination defect part in combination with the depth information of the echo signal.
[0024] Embodiment 2: As an optimization of the above embodiment, in step S1, the scanning surface of the ultrasonic test is the outer side surface of the thicker outer metal layer of the multi-layer metal material explosion composite steel plate, and the punching surface of the flat-bottomed blind hole is the other outer side surface of the multi-layer metal material explosion composite steel plate. Using the outer side surface of one side of the thicker outer metal layer as the scanning surface of the ultrasonic test can avoid the influence of the ultrasonic probe initial pulse signal and the 3 times near field area of the probe sound beam on the detection.
[0025] Embodiment 3: As an optimization of the above embodiment, in step S1, the bottom of the flat-bottomed blind hole is located on the target interface, and the distance from the punching surface of the flat-bottomed blind hole to the target interface is the depth of the flat-bottomed blind hole. That is, the bottom of the flat-bottomed blind hole is used to simulate the interface stratification state of the two metal materials.
[0026] Embodiment 4: As an optimization of the above embodiment, in step S1, the spacing between the flat-bottomed blind holes is 40 mm to 200 mm. The spacing between the flat-bottomed blind holes is based on the fact that the detection signals of adjacent flat-bottomed blind holes do not affect each other, and is generally greater than or equal to 40 mm.
[0027] Embodiment 5: As an optimization of the above embodiment, in step S1, the diameter of the flat-bottomed blind hole is 1 mm to 25 mm, and the number of the flat-bottomed blind holes of the series aperture is 5 to 15.
[0028] Embodiment 6: As an optimization of the above embodiment, in step S2, the ultrasonic probe used for ultrasonic testing is a single crystal ultrasonic straight probe. The frequency and diameter of the single crystal ultrasonic straight probe are selected based on the principle that the interface wave signals of the metal materials on both sides of the target interface can be accurately distinguished, and the target interface must be located outside the three times near field length of the ultrasonic probe sound field. According to 3N=D 2 / 4λ (N is the near-field length of the straight probe, D is the diameter of the probe wafer, and λ is the wavelength). The target interface must be located in the far field of the ultrasonic sound field, that is, 3N should be less than the distance from the scanning surface to the target interface.
[0029] Embodiment 7: As an optimization of the above embodiment, in step S2, the amplitude of the echo signal is represented by the gain value of the ultrasonic detection equipment under the same reference wave height.
[0030] Ultrasonic testing generally refers to the interaction between ultrasonic waves and workpieces, and the reflection and transmission on heterogeneous interfaces. Ultrasonic waves propagate in different media, and the acoustic impedances on both sides of the interface are different. If the acoustic impedances differ greatly, a stable interface echo will be received during ultrasonic testing. When ultrasonic testing is performed on multi-layer metal material explosion composite steel plates, a stable interface echo will be obtained. This stable interface echo is relatively easy to identify. By determining the changing characteristics of the interface echo, it can be determined whether there is stratification or weak bonding at the composite interface of the multi-layer metal material explosion composite steel plate, such as the explosion composite interface of aluminum-steel, copper-aluminum, copper-steel, etc. The present invention fully considers the amplitude and depth position information of the reflected waveform at the stratified defect site, and improves the accuracy of the identification of small-sized stratified defects of multi-layer metal material explosion composite steel plates and the measurement of equivalent dimensions. The present invention obtains the amplitude of the echo at the delamination defect of the explosion composite steel plate of the multi-layer metal material through the radio frequency waveform display of the delamination part waveform, analyzes in detail the influence of defects of different sizes on the echo amplitude, and establishes the relationship curve between the aperture of the flat-bottom blind hole and the amplitude of the corresponding echo signal by detecting the delamination defects of a series of flat-bottom blind holes with different apertures, that is, establishes the relationship between the equivalent size of the delamination defect and the echo amplitude, quickly detects the delamination defects of small areas on the interface of the composite material, improves the detection accuracy of the delamination defects of small areas, and combines the depth position of the delamination defect echo to comprehensively determine the size and depth of the delamination defect.
[0031] Combination Figure 1 The scheme of the present invention is described in detail, as Figure 1As shown, the interface between metal material 2 and metal material 3 in a multi-layer metal material explosion composite steel plate is the target interface, and metal material 4 is the thicker layer in the outer metal layer (metal material 1 and metal material 4). The outer side surface of one side of metal material 4 is used as the scanning surface, and the outer side surface of one side of metal material 1 is used as the punching surface of the flat-bottom blind hole. The flat-bottom blind hole is processed from the punching surface of the flat-bottom blind hole to the target interface. The depth of the flat-bottom blind hole is the sum of the thickness of metal material 1 and the thickness of metal material 2, that is, the bottom of the flat-bottom blind hole is located on the target interface. In actual detection, different punching depths can be selected according to actual conditions to simulate the flat-bottom hole delamination defects at different interfaces. The diameter of the flat-bottom blind hole is Φ1mm to Φ25mm. Within this range, the aperture distribution of the flat-bottom blind hole with a series of apertures is designed according to actual needs. The spacing between the two flat-bottom blind holes is based on the accurate identification of the defect signal and no mutual influence, and the spacing must be greater than or equal to 40mm. When selecting a single crystal ultrasonic straight probe, the near field length of the single crystal ultrasonic straight probe should be located in the metal material 4 medium for 3 times as long as possible. The frequency of the straight probe should be able to accurately distinguish the interface wave signals of metal material 3 and metal material 2. If the thickness of metal material 3 and metal material 2 is relatively thin, the probe frequency can be appropriately increased. The interface of the multi-layer metal material explosion composite steel plate is a wavy morphology, as shown in Figure 1. Figure 2 . The interface with good explosive composite is in the wavy bonding area, where the metals are tightly bonded, and a wavy morphology with peaks and troughs appears. When ultrasonic waves are incident on the interface, there is a difference in reflection and transmission from the smooth interface, so the amplitude of the defect signal of flat-bottomed blind holes of different diameters shall be based on actual measurements. The conventional ultrasonic detection echo signal is displayed on the display screen of the detection instrument in the form of a full wave after detection. For multi-layer metal material explosive composite steel plates, the interface wave 1 and interface wave 2 signals on both sides of a layer of metal material without defects are weak ( Figure 3 ), after amplification of interface waves 1 and 2, we get Figure 4 , the full-wave signal after detection loses its phase information, and the interface wave 1 and interface wave 2 at the defect-free position can be displayed using non-detection signals (i.e., RF signals) ( Figure 5 ), which contains phase and amplitude information, and is used to analyze the characteristics of the echo signal, which can improve the measurement accuracy of smaller delamination defects. The echo signal is displayed in the form of a radio frequency waveform. In the present invention, the amplitude of the echo signal is represented by the gain value of the detection device under the same reference wave height.
[0032] Embodiment 8: The "5083 aluminum-magnesium alloy-304L stainless steel" multi-layer metal material explosion composite joint is used as the test object. The joint is composed of five layers of metal materials. First, confirm the composite method of the multi-layer metal material, the grade of each layer of metal material, the thickness of each layer of metal, the multi-layer metal composite surface to be detected, and the area that can be detected. The metal materials of this embodiment are: 5083 aluminum-magnesium alloy + aluminum plate (Al: 95.39%) + titanium plate (Ti: 98.17%) + nickel plate (Ni: 97.65%) + 304L. The thickness of the metal material: 5083 aluminum-magnesium alloy + aluminum plate (Al: 95.39%) is 23.5mm in total; titanium plate (Ti: 98.17%) is 1.9mm; nickel plate (Ni: 97.65%) is 1.6mm; 304L is 9mm. During the use of the joint, local delamination leakage occurs at the titanium / nickel interface. It is necessary to detect the composite quality of the titanium / nickel interface, so the "bottom" of the flat-bottomed blind hole is set at the titanium / nickel interface to simulate delamination defects of different sizes. The area that can be ultrasonically tested is the area where there are no processed holes, grooves, steps, etc. The ultrasonic detection probe can be placed stably and the upper and lower surfaces of the detection area are parallel.
[0033] The specific detection steps are as follows: In the first step, a multilayer metal material explosion composite steel plate with the same specifications and materials as the multilayer metal material explosion composite joint is selected as a comparison test block. The composite structure of the multilayer metal material explosion composite steel plate is as follows: Figure 6 As shown, the outer side of the 5083 aluminum-magnesium alloy layer is used as the scanning surface for ultrasonic testing to avoid the influence of the ultrasonic probe initial pulse signal and the 3 times near field area of the probe sound field on the detection. A hole is punched from one side of the 304L layer to make a series of flat-bottomed blind holes with a depth of 10.6±0.08mm. The bottom of the flat-bottomed blind hole is located at the titanium / nickel interface. The diameters of the flat-bottomed blind holes are Φ2mm, Φ3mm, Φ5mm, Φ8mm, and Φ10mm. The spacing between the flat-bottomed blind holes is greater than 40mm. See the schematic diagram of the flat-bottomed blind hole depth. Figure 6 , see the schematic diagram of the comparison test block Figure 7 .
[0034] In the second step, an ultrasonic detection instrument is used to perform ultrasonic detection on the target interface by scanning the surface. First, the ultrasonic detection instrument and the probe are matched (this embodiment uses a conventional A-type pulse reflection ultrasonic detection instrument). When selecting a single-crystal ultrasonic straight probe, the 3 times near-field length of the probe sound field should be as small as possible to be less than the sum of the thicknesses of the 5083 aluminum-magnesium alloy + aluminum plate (Al: 95.39%), a total of 23.5 mm. The acoustic impedances of the 5083 aluminum-magnesium alloy and the aluminum plate (Al: 95.39%) in this material are very close, almost fully transmitted, and no interface wave signal is generated. The 3 times near-field length of the probe sound beam can be set to be less than the sum of their thicknesses. The titanium plate (Ti: 98.17%) is 1.9 mm, and the nickel plate (Ni: 97.65%) is 1.6 mm. Properly increasing the frequency of the single-crystal straight probe can improve the identifiability of the interface waves on both sides of the thin metal material. Therefore, the frequency of the selected single-crystal ultrasonic straight probe is 10 MHz and the diameter is Φ3 mm. Ultrasonic testing is performed on flat-bottomed blind holes of different apertures to obtain the amplitude of the echo signal of the target interface ultrasonic testing. When measuring the amplitude, Figure 8 , 9 As shown in the figure, taking 80% of the first wave peak of the delamination defect signal as the benchmark, the first wave peak of the signal is raised to 80% as the measurement point, and the gain value of the equipment is recorded, as shown in Table 1. According to the data in Table 1, a scatter plot of the aperture-amplitude of the flat-bottomed blind hole is drawn, and the relationship curve between the aperture of the flat-bottomed blind hole and the amplitude of the corresponding echo signal is obtained by power exponential fitting. The fitting equation of the curve is y=71.085χ -0.23 , correlation coefficient R 2 =0.9702; In the third step, ultrasonic testing is performed on multiple "5083 aluminum-magnesium alloy-304L stainless steel" multilayer metal material explosive composite joints under the same ultrasonic testing conditions as in the second step to obtain the echo signal amplitude of the sample to be tested. According to the relationship curve between the aperture of the flat-bottomed blind hole and the amplitude of the corresponding echo signal, the equivalent size of the delamination defect part of the sample to be tested is obtained. The depth of the suspicious signal part is obtained from the instrument. The size and depth of the delamination defect part are comprehensively analyzed. The results of the delamination defects detected in the multilayer metal material explosive composite joint are shown in Table 2.
[0035] In summary, the present invention proposes an ultrasonic detection method based on the ultrasonic reflection and transmission principle, which is used to detect the bonding status of the delamination interface of multi-layer metal material explosion composite steel plate, and uses an ultrasonic method to detect the interface of the multi-layer metal composite layer, comprehensively considers the amplitude and depth position information of the reflection waveform of the delamination defect part, and simulates the delamination defect through a flat-bottomed blind hole to realize ultrasonic detection of small-sized delamination defects, improves the equivalent size detection accuracy of smaller delamination defects, and accurately determines the size and vertical distribution of delamination defects. For the detection of the interface of parts made of multi-layer metal material explosion composite steel plate, the present invention improves the identifiability of small delamination defects at the composite interface and the accuracy of size measurement, and improves the qualified rate of parts product processing.
[0036] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.
Claims
1. An ultrasonic detection method for delamination of explosive composite steel plates of multi-layer metal materials, Features Follow these steps: S1, select a multi-layer metal material explosive composite steel plate with the same specifications and materials as the sample to be tested as a comparison test block, determine the scanning surface of the ultrasonic test and the punching surface of the flat-bottom blind hole, and drill holes from the punching surface of the flat-bottom blind hole and the target interface on the comparison test block to make flat-bottom blind holes with a series of apertures; S2, using an ultrasonic testing instrument to perform ultrasonic testing on flat-bottomed blind holes of a series of apertures on a scanning surface, obtaining the echo signal amplitude of the flat-bottomed blind holes on the target interface, and making a relationship curve between the aperture of the flat-bottomed blind holes and the corresponding echo signal amplitude; S3, testing the sample to be tested under the same ultrasonic testing conditions as in step S2, obtaining the amplitude of the delamination defect echo signal of the target interface of the sample to be tested, and then comparing the relationship curve between the amplitude of the delamination defect echo signal on the sample to be tested and the aperture of the flat-bottomed blind hole and the corresponding echo signal amplitude, to obtain the equivalent size of the delamination defect part of the sample to be tested, and comprehensively analyzing the size and depth of the delamination defect part in combination with the depth information of the echo signal.
2. The ultrasonic detection method for delamination of multi-layer metal material explosive composite steel plate according to claim 1, Features In step S1, the scanning surface of the ultrasonic inspection is the outer side surface of the thicker layer of the outer metal layer of the multi-layer metal material explosion composite steel plate, and the punching surface of the flat-bottomed blind hole is the other outer side surface of the multi-layer metal material explosion composite steel plate.
3. The ultrasonic detection method for delamination of multi-layer metal material explosion-composite steel plate according to claim 1 or 2, Features In step S1, the bottom of the flat-bottomed blind hole is located on the target interface, and the distance from the punching surface of the flat-bottomed blind hole to the target interface is the depth of the flat-bottomed blind hole.
4. The ultrasonic detection method for delamination of multi-layer metal material explosive composite steel plate according to claim 1, Features In step S1, the spacing between the flat-bottomed blind holes is 40 mm to 200 mm.
5. The ultrasonic detection method for delamination of multi-layer metal material explosion-composite steel plate according to claim 2 or 4, Features In step S1 , the diameter of the flat-bottomed blind hole is 1 mm to 25 mm, and the number of the flat-bottomed blind holes of the series aperture is 5 to 15.
6. The ultrasonic detection method for delamination of multi-layer metal material explosive composite steel plate according to claim 5, Features In step S2, the ultrasonic probe used for ultrasonic testing is a single crystal ultrasonic straight probe. The frequency and diameter of the single crystal ultrasonic straight probe are selected based on the following principles: the interface wave signals of the metal materials on both sides of the target interface can be accurately distinguished, and the target interface must be located outside the three times near field length of the ultrasonic probe sound field.
7. The ultrasonic detection method for delamination of multi-layer metal material explosion-composite steel plates according to claim 4 or 6, Features In step S2, the amplitude of the echo signal is represented by the gain value of the ultrasonic detection device at the same reference wave height.