Method and system for characterizing internal structure of composite material based on transmission acoustic wave spectrum

Abstract

The invention provides a composite material internal structure characterization method and system based on a transmission sound wave spectrum. The method comprises the following steps: performing transmission method ultrasonic scanning on a composite material to generate different transmission sound wave maps aiming at different detection frequencies; and characterizing a minimum repeating unit in each transmitted acoustic wave scan image in each transmitted acoustic wave map. According to the method, a composite material transmission sound wave spectrum is established, the quantitative relation between the internal structures of different composite materials and transmission sound wave image characteristic elements is established by identifying and quantifying the characteristic elements of transmission ultrasonic scanning images, ultrasonic characterization of the internal structures of the composite materials is achieved, and the method can be suitable for ultrasonic characterization of the internal structures of the composite materials of different structures.

Description

Technical Field

[0001] The invention relates to the field of composite material detection, and mainly to a method and system for characterizing the internal structure of a composite material based on a transmission acoustic wave spectrum. Background Art

[0002] Composite materials are composed of two or more different materials. Compared with traditional metal materials, composite materials exhibit anisotropic characteristics, that is, in different directions, the material exhibits different properties, such as mechanical and acoustic properties. In terms of the characterization of the anisotropy and structural characterization of composite materials, the characterization of the anisotropy and internal structure of composite materials is currently mainly achieved through destructive mechanical experimental measurement methods and microscopic observation methods, such as tensile, compression, bending, shear mechanical test determination and metallographic microscope observation. This destructive mechanical testing method is relatively direct, but because it requires destructive experiments on the specimen, it is greatly limited in actual application. How to characterize the internal structure of composite materials without destroying the material has become a difficulty in the characterization of composite material performance.

[0003] The patent with publication number CN111289620A discloses a method for detecting elastic constants of anisotropic materials. The method obtains a V(z) curve by measuring the reflected sound wave signal, establishes the relationship between the V(z) curve and the elastic tensor, obtains the elastic tensor by fitting and iterating the theoretical value and the measured value, and realizes the anisotropic characterization of the composite material. However, the method uses reflection ultrasonic testing to realize anisotropic characterization, which is not applicable to penetration ultrasonic testing.

[0004] Therefore, it is necessary to develop ultrasonic properties characterization methods for composite materials suitable for penetration method. Summary of the invention

[0005] This Summary is provided to introduce some concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0006] According to one embodiment of the present invention, a method for characterizing the internal structure of a composite material based on a transmission acoustic wave spectrum is provided, comprising: generating different transmission acoustic wave spectra for different detection frequencies by performing transmission ultrasonic scanning on the composite material; and characterizing the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum.

[0007] According to another embodiment of the present invention, a system for characterizing the internal structure of a composite material based on a transmission acoustic wave spectrum is provided, comprising: a transmission acoustic wave spectrum generation module, the transmission acoustic wave spectrum generation module is configured to generate different transmission acoustic wave spectra for different detection frequencies by performing a transmission ultrasonic scanning on the composite material; and a minimum repeating unit characterization module, the minimum repeating unit characterization module is configured to characterize the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum.

[0008] According to another embodiment of the present invention, a computing device for characterizing the internal structure of a composite material based on a transmission acoustic wave spectrum is provided, comprising: a processor; a memory storing instructions, which can execute the above method when executed by the processor.

[0009] These and other features and advantages will become apparent by reading the following detailed description and by reference to the associated drawings.It is to be understood that the foregoing general description and the following detailed description are illustrative only and are not restrictive of the aspects of what is claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to understand the manner in which the above features of the present invention are used in detail, the above briefly summarized contents can be described in more detail with reference to various embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only show some typical aspects of the present invention and should not be considered to limit its scope, because the description may allow for other equally effective aspects.

[0011] Figure 1 A schematic diagram of a method 100 for characterizing the internal structure of a composite material based on transmission acoustic wave atlas according to one or more embodiments of the present invention is shown.

[0012] Figure 2 The present invention shows one or more embodiments of the present invention. Figure 1 Detailed flow chart 200 of stage 105 in FIG.

[0013] Figure 3 A schematic diagram of a transmission ultrasound scanning device 300 that can be used to scan composite materials is shown.

[0014] Figure 4 A single example transmission ultrasound scan image 400 is shown.

[0015] Figure 5 A transmission acoustic wave map 500 for a specific detection frequency composed of 12 transmission ultrasound scan images is shown.

[0016] Figure 6 The present invention shows one or more embodiments of the present invention. Figure 1 Detailed flowchart 600 of stage 110 in FIG.

[0017] Figure 7 A converted grayscale image 700 corresponding to the transmitted acoustic scanning image is shown.

[0018] Figure 8 A transmission acoustic wave scanning image 800 after feature extraction is shown.

[0019] Fig. 9 The identified minimal repeating unit and its characteristic elements are shown.

[0020] Fig.10 Shown with Fig. 9 The lattice structure model 1000 corresponds to the smallest repeating unit in .

[0021] Fig.11 A schematic diagram of a system 1100 for characterizing the internal structure of a composite material based on transmission acoustic wave atlas according to one or more embodiments of the present invention is shown.

[0022] Fig.12 Block diagram 1200 of an exemplary computing device is shown in accordance with one or more embodiments of the invention. DETAILED DESCRIPTION

[0023] The present invention will be described in detail below in conjunction with the accompanying drawings, and the features of the present invention will be further revealed in the following specific description.

[0024] In order to overcome the shortcomings of existing ultrasonic detection and characterization methods for characterizing the internal structure and performance of composite materials, which lack a penetration ultrasonic detection and characterization method, the present invention proposes a scheme for characterizing the internal structure of composite materials based on a transmission acoustic wave spectrum. The scheme establishes a transmission acoustic wave spectrum of a composite material, and by identifying and quantifying the characteristic elements of a transmission ultrasonic scanning image, establishes a quantitative relationship between the internal structure of different composite materials and the characteristic elements of the transmission acoustic wave image, and realizes the ultrasonic characterization of the internal structure of the composite material, which can be applied to the ultrasonic characterization of the internal structure of composite materials with different structures.

[0025] Figure 1 A schematic diagram of a method 100 for characterizing the internal structure of a composite material based on transmission acoustic wave atlas according to one or more embodiments of the present invention is shown.

[0026] In stage 105, a transmission ultrasonic scan is performed on the composite material to generate different transmission acoustic wave spectra for different detection frequencies.

[0027] According to an embodiment of the present invention, each transmission acoustic wave atlas includes a plurality of transmission acoustic wave scanning images generated at different scanning angles using one detection frequency.

[0028] In stage 110, the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum is characterized, thereby completing the characterization of the internal structure of the composite material.

[0029] According to an embodiment of the present invention, characterizing the minimum repeating unit in the transmission acoustic wave scanning image includes characterizing the minimum repeating unit using characteristic elements of the minimum repeating unit.

[0030] According to one embodiment of the present invention, stage 110 may be performed after each transmission acoustic wave scanning image is generated in stage 105, that is, when a transmission acoustic wave scanning image is generated, the characteristic elements of the minimum repeating unit in the transmission acoustic wave scanning image are characterized. According to another embodiment of the present invention, stage 110 may be performed after the transmission acoustic wave spectrum is generated in stage 105, that is, after all transmission acoustic wave scanning images are generated, the characteristic elements of the minimum repeating unit in each transmission acoustic wave scanning image are characterized respectively.

[0031] Figure 2 The present invention shows one or more embodiments of the present invention. Figure 1 Detailed flow chart 200 of stage 105 in FIG.

[0032] At 205, the transmission sound wave scanning area of ​​the composite material is determined. According to one embodiment of the present invention, for example, the scanning area can be selected according to the structural characteristics of the composite material (for example, the size and shape of the composite material itself). In addition, the selected scanning area is two-dimensional, and its area size can be expressed as L×W.

[0033] For example, if the composite material to be tested is a woven composite material and its size is: 330 mm×69 mm×5.5 mm, the area size of the transmission acoustic wave scanning area can be determined as length L=50 mm and width W=30 mm.

[0034] At 210, a detection frequency set is determined. According to one embodiment of the present invention, the detection frequency set includes one or more detection frequencies. For example, one or more detection frequencies may be determined based on the thickness of the composite material, the acoustic attenuation characteristics, etc., so as to make the generated transmission acoustic wave scanning image clearer. For example, the detection frequency may be multiple, such as f 1 , f 2 , …, f i , where i is an integer. In the following, I max Indicates the number of determined detection frequencies.

[0035] Continuing with the above example of a woven composite material, it is determined that two detection frequencies (i.e., I max =2) to scan, respectively f 1=5MHz, f 2 =1MHz.

[0036] At 215, a set of scanning angles is determined. According to one embodiment of the present invention, the set of scanning angles includes one or more scanning angles. For example, one or more scanning angles may be determined based on the size, thickness, acoustic attenuation characteristics, etc. of the composite material, such as φ 1 ,φ 2 ,…,φ j , where j is an integer. In the following, J max Indicates the number of scan angles determined.

[0037] Continuing with the above example of a woven composite material, the 12 scanning angles (i.e., J max =12) to scan, respectively: φ 1 =0°,φ 2 =5°,φ 3 =10°,φ 4 =15°,φ 5 =20°,φ 6 =25°,φ 7 =35°,φ 8 =40°,φ 9 =45°,φ 10 =50°,φ 11 =55°,φ 12 =60°.

[0038] At 220 , a transmission acoustic wave scanning area of ​​the composite material is scanned using a current detection frequency in the determined detection frequency set and each scanning angle in the determined scanning angle set to generate a transmission acoustic wave spectrum for the current detection frequency.

[0039] According to an embodiment of the present invention, when entering step 220 for the first time, the current detection frequency is the first detection frequency in the detection frequency set.

[0040] According to one embodiment of the present invention, the transmission acoustic wave atlas includes one or more transmission acoustic wave scanning images, and each of the one or more transmission acoustic wave scanning images corresponds to a corresponding scanning angle in the scanning angle set.

[0041] For example, Figure 3The schematic diagram of a transmission ultrasonic scanning device 300 that can be used to scan the transmission acoustic wave scanning area of ​​the composite material is shown. As can be seen from the schematic diagram, the scanning device 300 uses two ultrasonic probes, wherein the transmitting probe 301 transmits ultrasonic waves and the receiving probe 302 receives ultrasonic waves. The scanning device 300 can adjust the scanning angle (or, referred to as "incident angle") to obtain multiple transmission acoustic wave scanning images. Specifically, the scanning device 300 uses one of the detection frequencies (e.g., f ) in the detection frequency set determined in step 210 for the transmission acoustic wave scanning area of ​​the composite material determined in step 205. 1 ) and each scanning angle φ in the scanning angle set determined in step 215 j To perform transmission ultrasound scanning imaging, thereby generating a scanning angle φ j Finally, the multiple transmission acoustic wave scanning images generated by using different scanning angles in the scanning angle set constitute a plurality of transmission acoustic wave scanning images for the detection frequency (for example, f 1 ) of the transmitted sound wave spectrum.

[0042] Continuing with the above example of woven composite materials, the detection frequency f 1 =5MHz, and scanning angles of 0°, 5°, 10°, 15°, 20°, 25°, 35°, 40°, 45°, 50°, 55°, and 60° are used in sequence to perform transmission ultrasonic scanning on the selected inspection area of ​​the woven composite material, thereby obtaining 12 two-dimensional transmission ultrasonic scanning images (size is L×W=50mm×30mm). Figure 4 A single example transmission ultrasound scan image 400 is shown, Figure 5 The image is shown as a graph consisting of 12 transmission ultrasound scan images for a specific detection frequency (e.g., f 1 =5MHz) transmitted acoustic wave spectrum 500.

[0043] At 225, it is determined whether there is a next unused detection frequency in the determined detection frequency set (for example, it can be determined whether i max If yes, the loop returns to step 220, and the next unused detection frequency is used as the current detection frequency in step 220. If no, the method 200 ends.

[0044] Continuing with the above example of a woven composite material, in the above first entry step 220, f 1 =5MH, the detection frequency f can be determined 2 = 1 MHz has not been used (ie, 1<2). Therefore, the detection frequency f is continued to be used. 2 ​=1MHz, and sequentially use scanning angles of 0°, 5°, 10°, 15°, 20°, 25°, 35°, 40°, 45°, 50°, 55°, and 60° to perform transmission ultrasonic scanning on the selected inspection area of ​​the woven composite material, thereby generating a transmission ultrasonic scanning image consisting of 12 images for f 2 = Transmitted acoustic wave spectrum of 1MHz.

[0045] Figure 6 The present invention shows one or more embodiments of the present invention. Figure 1 Detailed flowchart 600 of stage 110 in FIG.

[0046] At 605, for each generated transmission acoustic wave scanning image, feature elements of the minimum repeating unit are identified and extracted, and the feature elements characterize the morphology of the minimum repeating unit. For example, the minimum repeating unit may be a minimum feature set consisting of one or more features that appear repeatedly in the transmission acoustic wave scanning image, and the feature elements may include parameters describing the distance, relative angle, etc. between the features constituting the minimum repeating unit.

[0047] According to an embodiment of the present invention, step 605 may optionally include converting the transmission acoustic wave scanning image into a grayscale image. Figure 7 The converted grayscale image corresponding to the transmission acoustic wave scanning image is shown as 700. Of course, the identification and extraction of the minimum repeating unit can also be performed on the color transmission acoustic wave scanning image.

[0048] According to one embodiment of the present invention, step 605 may include extracting features of the transmitted acoustic wave scanning image. Figure 8 The transmitted acoustic wave scanning image 800 after feature extraction is shown. Figure 8 It can be concluded that in image 800 , the transmission acoustic wave scanning image is denoised, and the outline of each feature in the image is highlighted.

[0049] According to an embodiment of the present invention, step 605 further includes identifying a minimal repeating unit and a characteristic element of the minimal repeating unit based on the extracted features.

[0050] Continuing with the above example of woven composites, Fig. 9 The identified minimum repeating unit, as well as the unit size a, unit size b, and angles α, β and other characteristic elements of the minimum repeating unit are shown. Fig.10 Shown with Fig. 9 The lattice structure model 1000 corresponds to the smallest repeating unit in .

[0051] For example, see Fig. 9 and Fig.10, the minimum repeating unit can be regarded as a unit with a basic rhombus morphology composed of four features A, B, C and D, that is, the side length AD and the side length BC can be regarded as basically equal, and the side length AB and the side length DC can be regarded as basically equal. Among them, a represents the length of one side of the rhombus, and b represents the length of the other side of the rhombus. Similarly, α and β respectively represent the two vertex angles of the minimum repeating unit, for example, α represents the angle between the side length AD and the side length AB, and β represents the angle between the side length AB and the side length BC.

[0052] Those skilled in the art can understand that Fig. 9 The morphology and characteristic elements of the minimum repeating unit shown in the figure are merely schematic. In practice, different characteristic elements may be used for characterization according to the specific morphology of the identified minimum repeating unit.

[0053] At 610, characteristic elements of the minimal repeating unit are measured, and the measured values ​​of the characteristic elements are recorded.

[0054] According to one embodiment of the present invention, step 610 may include measuring the unit elements of the minimum repeating unit identified in step 605, and recording the values ​​of the measured characteristic elements in the form of the following table:

[0055]

[0056] Continuing with the above example of woven composite materials, the following table shows the 1 =Specific characteristic element values ​​of the minimum repeating unit at different scanning angles of 5MHz:

[0057]

[0058]

[0059] Fig.11 A schematic diagram of a system 1100 for characterizing the internal structure of a composite material based on a transmission acoustic wave spectrum according to one or more embodiments of the present invention is shown. As shown in the figure, the system 1100 mainly includes a transmission acoustic wave spectrum generation module 1105 and a minimum repeating unit characterization module 1110.

[0060] It is fully understood by those skilled in the art that the division of the above modules is only explained for the purpose of clarity. The functions of one or more of the above modules can be combined into a single module or split into more modules / submodules. Moreover, one or more of the above modules can be implemented by software, hardware or a combination thereof. In addition, the data flow between the modules can be implemented in a manner known in the art, which is not within the scope of the present invention.

[0061] According to one embodiment of the present invention, the transmission acoustic wave spectrum generation module 1105 may be configured to generate different transmission acoustic wave spectrums of the composite material for different detection frequencies. Each transmission acoustic wave spectrum includes a plurality of transmission acoustic wave scanning images generated at different scanning angles using one detection frequency. For example, the transmission acoustic wave spectrum generation module 1105 may be configured to perform Figure 2 Method 200 is described.

[0062] According to one embodiment of the present invention, the minimum repeating unit characterization module 1110 may be configured to characterize the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum, thereby completing the characterization of the internal structure of the composite material. For example, the minimum repeating unit characterization module 1110 may be configured to perform Figure 6 Method 600 is described.

[0063] In summary, the composite material transmission acoustic wave spectrum and the method for characterizing its internal structure proposed in the present invention are suitable for ultrasonic characterization of the internal structure of composite materials with different structures, and have at least the following beneficial effects:

[0064] 1) An ultrasonic characterization method suitable for the internal structure of composite materials is proposed;

[0065] 2) An experimental method for transmission acoustic wave mapping of composite materials was established;

[0066] 3) Ultrasonic characterization of the internal structure of composite materials was achieved.

[0067] Fig.12 FIG. 1 is a block diagram 1200 of an exemplary computing device according to one embodiment of the present invention, which is an example of a hardware device that can be applied to various aspects of the present invention. Fig.12, a computing device 1200 will now be described, which is an example of a hardware device applicable to various aspects of the present invention. The computing device 1200 can be any machine that can be configured to implement processing and / or calculations, and can be, but is not limited to, a workstation, a server, a desktop computer, a laptop computer, a tablet computer, a personal digital processing, a smart phone, a car computer, or any combination thereof. The computing device 1200 may include components that can be connected or communicated via one or more interfaces and a bus 1202. For example, the computing device 1200 may include a bus 1202, one or more processors 1204, one or more input devices 1206, and one or more output devices 1208. The one or more processors 1204 can be any type of processor and can include, but are not limited to, one or more general-purpose processors and / or one or more special-purpose processors (e.g., a dedicated processing chip). The input device 1206 can be any type of device capable of inputting information to the computing device and can include, but are not limited to, a mouse, a keyboard, a touch screen, a microphone, and / or a remote controller. The output device 1208 can be any type of device capable of presenting information and can include, but are not limited to, a display, a speaker, a video / audio output terminal, a vibrator, and / or a printer. The computing device 1200 may also include or be connected to a non-transient storage device 1210, which may be any storage device that is non-transient and capable of data storage, and may include, but is not limited to, a disk drive, an optical storage device, a solid-state memory, a floppy disk, a floppy disk, a hard disk, a tape or any other magnetic medium, an optical disk or any other optical medium, a ROM (read-only memory), a RAM (random access memory), a cache memory, and / or any memory chip or cassette, and / or any other medium from which a computer can read data, instructions, and / or code. The non-transient storage device 1210 may be detachable from the interface. The non-transient storage device 1210 may have data / instructions / code for implementing the above methods and steps. The computing device 1200 may also include a communication device 1212. The communication device 1212 can be any type of device or system that can communicate with internal devices and / or with a network and can include but is not limited to a modem, a network card, an infrared communication device, a wireless communication device and / or a chipset, such as a Bluetooth device, an IEEE 1302.11 device, a WiFi device, a WiMax device, a cellular communication device and / or the like.

[0068] The bus 1202 may include, but is not limited to, an Industry Standard Architecture (ISA) bus, a Micro Channel Architecture (MCA) bus, an Enhanced ISA (EISA) bus, a Video Electronics Standards Association (VESA) local bus, and a Peripheral Component Interconnect (PCI) bus.

[0069] The computing device 1200 may also include a working memory 1214 , which may be any type of working memory capable of storing instructions and / or data that facilitate the operation of the processor 1204 and may include, but is not limited to, a random access memory and / or a read-only storage device.

[0070] Software components may be located in the working memory 1214, including but not limited to an operating system 1216, one or more application programs 1218, drivers and / or other data and codes. Instructions for implementing the above methods and steps of the present invention may be included in the one or more application programs 1218, and the processor 1204 may read and execute the instructions of the one or more application programs 1218 to implement the above method 100 of the present invention.

[0071] It should also be recognized that changes may be made according to specific needs. For example, custom hardware may also be used, and / or specific components may be implemented in hardware, software, firmware, middleware, microcode, hardware description language, or any combination thereof. In addition, connections to other computing devices, such as network input / output devices, etc. may be employed. For example, programming hardware (e.g., programmable logic circuits including field programmable gate arrays (FPGAs) and / or programmable logic arrays (PLAs)) with assembly language or hardware programming languages ​​(e.g., VERILOG, VHDL, C++) may be used to implement part or all of the disclosed methods and devices using logic and algorithms according to the present invention.

[0072] Although various aspects of the present invention have been described so far with reference to the accompanying drawings, the above-described methods and apparatus are merely examples, and the scope of the present invention is not limited to these aspects, but is limited only by the appended claims and their equivalents. Various components may be omitted or replaced by equivalent components. In addition, the steps may be implemented in an order different from the order described in the present invention. In addition, various components may be combined in various ways. It is also important that, as technology develops, many of the components described may be replaced by equivalent components that appear later.

Claims

1. A method for characterizing the internal structure of a composite material based on transmission acoustic wave atlas, include: By performing transmission ultrasonic scanning on the composite material, different transmission acoustic wave spectra for different detection frequencies are generated; as well as The smallest repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum is characterized.

2. The method according to claim 1, It is characterized in that Each transmission acoustic wave spectrum includes a plurality of transmission acoustic wave scanning images generated at different scanning angles using one detection frequency.

3. The method according to claim 1, It is characterized in that Generating different transmission acoustic wave spectra for different detection frequencies further includes: determining a transmission acoustic wave scanning area of ​​the composite material; determining a set of detection frequencies; and Determine the set of scan angles.

4. The method according to claim 3, It is characterized in that Generating different transmission acoustic wave spectra for different detection frequencies further includes: For each current detection frequency in the determined detection frequency set: The transmission acoustic wave scanning area of ​​the composite material is scanned using the current detection frequency and each scanning angle in the determined scanning angle set to generate a transmission acoustic wave spectrum for the current detection frequency.

5. The method according to claim 1, It is characterized in that Characterizing the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum further includes: For each transmitted acoustic wave scanning image, a characteristic element of a minimum repeating unit is identified and extracted, wherein the characteristic element characterizes the morphology of the minimum repeating unit.

6. The method according to claim 5, It is characterized in that Characterizing the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum further includes: The characteristic elements are measured, and the measured values ​​of the characteristic elements are recorded.

7. The method according to claim 5, It is characterized in that The minimum repeating unit is a minimum feature set consisting of one or more features that appear repeatedly in the transmission acoustic wave scanning image, and the feature elements include parameters that describe the distance and / or relative angle between the features constituting the minimum repeating unit.

8. A system for characterizing the internal structure of composite materials based on transmission acoustic wave atlas, include: a radio acoustic wave spectrum generating module, wherein the radio acoustic wave spectrum generating module is configured to generate different transmission acoustic wave spectra for different detection frequencies by performing transmission ultrasonic scanning on the composite material; and A minimum repeating unit characterization module is configured to characterize the minimum repeating unit in each transmission acoustic wave scanning image in each transmission acoustic wave spectrum.

9. The system of claim 8, It is characterized in that Each transmission acoustic wave spectrum includes a plurality of transmission acoustic wave scanning images generated at different scanning angles using one detection frequency.

10. A computing device for characterizing the internal structure of composite materials based on transmission acoustic wave atlas, include: processor; A memory storing instructions, wherein the instructions, when executed by the processor, can perform the method according to any one of claims 1 to 7.

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