Transparent material parameter measuring method and measuring system

Abstract

The invention provides a transparent material parameter measuring method and a transparent material parameter measuring system, which are used for solving the technical problems of large signal interference, low signal-to-noise ratio and the like of the existing non-contact measuring method. The measuring method comprises the following steps: 1, preparing a sample to be measured; 2, respectively dividing a bullet-facing surface and a non-bullet-facing surface of the to-be-detected sample into film coating areas, reserving a transparent area penetrating through the axial direction of the to-be-detected sample between the two film coating areas, and then respectively coating a layer of metal reflective film in each film coating area; 3, at least one PDV probe is arranged at the position, not affected by the side sparse waves, in the coating area of the non-bullet-facing face, at the position, not affected by the side sparse waves, in the non-coating area of the non-bullet-facing face and one end of the non-bullet-facing face of the transparent area respectively; and 4, impacting the to-be-tested sample from the bullet facing surface along the axial direction through the light-gas gun flat plate impact experiment device, respectively acquiring particle speed signals at corresponding positions and speed signals of the flyer by each PDV probe, and further calculating to obtain the flatness and the wave velocity of the to-be-tested sample.

Description

Technical Field

[0001] The invention relates to a material parameter measurement method, and in particular to a transparent material parameter measurement method and a measurement system. Background Art

[0002] The flat plate impact test under light gas gun loading is one of the main experimental means to study the dynamic properties and destructive behavior of materials under high impact pressure and high strain rate. This type of experimental test of the dynamic behavior of materials under high pressure and high strain rate conditions can be carried out through contact or non-contact measurement methods.

[0003] Contact measurement is to bury a manganese copper gauge or other thin film pressure sensor inside the sample and measure the stress history inside the material through the pressure sensor; or use an electromagnetic particle velocimeter to measure the movement speed of particles inside the material. This type of measurement method can only measure a single parameter, and the internal structure of the sample will be destroyed during measurement, and the overall test efficiency is low.

[0004] To solve the above problems, non-contact measurement methods are currently used. Non-contact measurement generally measures the velocity history of particles on the free surface of the material through VISAR (laser velocity interferometer) or PDV (photon Doppler velocimeter), and then obtains the Hugoniot elastic limit of the material, providing data support for the application of materials in the field of high-speed impact. This type of measurement method is relatively efficient in measuring the velocity of particles on the free surface of the material, but it is easily interfered by the internal motion signal of the material after impact compression and the reflected light on the surface of the material. The signal interference is large and the signal-to-noise ratio is low, making the final measurement result difficult to analyze. Summary of the invention

[0005] The object of the present invention is to provide a transparent material parameter measurement method and a measurement system, which are used to solve the technical problems of existing non-contact measurement methods such as large signal interference and low signal-to-noise ratio.

[0006] In order to achieve the above purpose, the technical solution provided by the present invention is as follows:

[0007] A method for measuring parameters of a transparent material, which is special in that it comprises the following steps:

[0008] Step 1, prepare a sample to be tested; the sample to be tested is made of transparent material and is cylindrical, and the two bottom surfaces of the sample to be tested are defined as a projectile-facing surface and a non-projectile-facing surface;

[0009] Step 2, dividing the coating area on the bullet-facing surface and the non-bullet-facing surface of the sample to be tested respectively, the coating areas on the two sides are staggered, and a transparent area that runs through the axial direction of the sample to be tested is left between the two, and then a layer of metal reflective film is coated in each coating area;

[0010] Step 3, at least one PDV probe is arranged in the coating area of ​​the non-ballistic surface not affected by the side rarefaction wave, in the non-coating area of ​​the non-ballistic surface not affected by the side rarefaction wave, and at one end of the non-ballistic surface of the transparent area; the non-coating area refers to a part of the non-ballistic surface that avoids the transparent area and the coating area and corresponds to the coating area of ​​the ballistic surface;

[0011] Step 4: Use the light gas gun flat plate impact test device to impact the sample to be tested axially from the projectile surface, and use each PDV probe to obtain the particle velocity signal at the corresponding position and the velocity signal of the flying piece, and then calculate the flatness and wave velocity of the sample to be tested.

[0012] Furthermore, step 2 is specifically as follows:

[0013] 2.1. The coating areas are divided on the bullet-facing surface and the non-bullet-facing surface of the sample to be tested, respectively. The coating areas on the bullet-facing surface and the non-bullet-facing surface are respectively fan-shaped areas with an angle of 180°. The arc edges of the two fan-shaped areas are arranged symmetrically along the radial direction and coincide with the circular edges of the surfaces on which they are located, so that the coating areas on the two surfaces are arranged in a staggered manner; the straight edges of the two fan-shaped areas are arranged in parallel, and a distance is left between the two radial directions, so that a transparent area that runs through the axial direction of the sample to be tested is left between the coating areas on the two surfaces;

[0014] 2.2. A layer of metal reflective film is coated on the fan-shaped area on the bullet-facing surface and the non-bullet-facing surface respectively.

[0015] Furthermore, in step 2.1, the radial distance between the straight sides of the two sector-shaped areas is greater than or equal to the radial maximum dimension of the PDV probe.

[0016] Furthermore, step 4 is specifically as follows:

[0017] 4.1. Use a light gas gun flat plate impact test device to impact the sample from the projectile surface along the axial direction, and use the PDV probes arranged in the coated area and non-coated area of ​​the non-projectile surface to obtain the particle velocity signals at the corresponding positions respectively, and use the PDV probes arranged in the transparent area to obtain the velocity signals of the flying pieces of the light gas gun flat plate impact test device;

[0018] 4.2. The flatness of the sample to be tested is calculated by the waveform starting time point in the particle velocity signal at the corresponding positions of the coating area and the non-coating area;

[0019] 4.3. The wave velocity of the sample to be tested is calculated by using the time difference between the starting points of the waveform in the material particle velocity signal at the corresponding positions of the coated area and the non-coated area.

[0020] Furthermore, in step 4.2, the calculation method of the flatness tanθ of the sample to be tested is:

[0021]

[0022] Among them, t1 is the waveform jump time point in the particle velocity signal of the non-coated area of ​​the non-projectile surface, t2 is the waveform jump time point in the particle velocity signal of the coated area of ​​the non-projectile surface, v is the impact velocity of the flying piece of the light gas gun flat plate impact test device, d is the distance between the PDV probe arranged in the coated area of ​​the non-projectile surface and the PDV probe arranged in the non-coated area of ​​the non-projectile surface, and θ is the angle between the axial direction of the sample to be tested and the flight direction of the flying piece.

[0023] Furthermore, in step 4.3, the calculation method of the wave velocity D of the sample to be tested is:

[0024]

[0025] Where h is the axial length of the sample to be tested.

[0026] At the same time, the present invention also provides a transparent material parameter measurement system for implementing the above transparent material parameter measurement method, which is special in that:

[0027] Includes a light gas gun flat plate impact test device, at least three PDV probes, and data acquisition equipment;

[0028] The light gas gun flat plate impact test device comprises a high-pressure gas chamber, a gun barrel installed at the outlet end of the high-pressure gas chamber, and a bullet and a flying piece installed in the gun barrel in sequence; the bullet is installed near the outlet end of the high-pressure gas chamber; the end of the gun barrel away from the high-pressure gas chamber is used to install the sample to be tested;

[0029] The PDV probes are respectively installed at a location in the coating area of ​​the non-bullet-facing surface of the sample to be tested that is not affected by the side rarefaction wave, a location in the non-coating area of ​​the non-bullet-facing surface that is not affected by the side rarefaction wave, and one end of the non-bullet-facing surface of the transparent area that passes through the axial direction of the sample to be tested;

[0030] The data acquisition device is connected to each PDV probe respectively, and is used to collect parameter information obtained by the PDV probe.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention provides a method for measuring parameters of transparent materials. Coating areas are set and coated on the two bottom surfaces of the sample to be tested, and PDV probes are arranged at corresponding positions on the non-projectile surface. Then, particle velocity signals are obtained by combining a light gas gun flat plate impact test with the PDV probes arranged at corresponding positions. The particle velocity signals are then used to calculate and obtain relevant parameters. This method solves the problem of many clutter signals in transparent material measurement in the flat plate impact test, thereby improving the signal-to-noise ratio and test accuracy.

[0033] 2. The present invention provides a method for measuring parameters of transparent materials, which can obtain multiple material parameters through one experiment, and some parameters can be verified with each other, thereby improving experimental efficiency and measurement accuracy.

[0034] 3. The present invention provides a method for measuring parameters of transparent materials with high speed accuracy, high dynamic range and high experimental efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the structure of a sample to be measured after coating in an embodiment of a method for measuring parameters of a transparent material of the present invention.

[0036] Figure 2 This is a side view of a sample to be measured after coating in an embodiment of a method for measuring parameters of a transparent material of the present invention.

[0037] Figure 3 It is a structural schematic diagram of an embodiment of a transparent material parameter measurement system of the present invention.

[0038] The reference numerals are as follows:

[0039] 1-PDV probe, 2-data acquisition equipment, 3-high pressure gas chamber, 4-gun barrel, 5-bullet, 6-flying piece, 7-sample to be tested. DETAILED DESCRIPTION

[0040] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] This embodiment provides a method for measuring parameters of a transparent material, comprising the following steps:

[0042] Step 1: Prepare the sample to be tested.

[0043] This embodiment is aimed at samples of transparent materials. Therefore, the sample 7 to be tested is made of transparent material and is cylindrical. The two bottom surfaces of the sample 7 to be tested are defined as a projectile-facing surface and a non-projectile-facing surface. The projectile-facing surface is the side that the flying piece first hits during the test.

[0044] Step 2: Divide the coating area and the transparent area.

[0045] 2.1. The coating areas are divided on the bullet-facing surface and the non-bullet-facing surface of the sample 7 to be tested, respectively. The coating areas on the bullet-facing surface and the non-bullet-facing surface are respectively fan-shaped areas with an angle of 180°. The arc edges of the two fan-shaped areas are radially symmetrically arranged and coincide with the circular edges of the surfaces on which they are located, respectively, so that the coating areas on the two surfaces are staggered. The straight edges of the two fan-shaped areas are arranged in parallel, and a distance is left between the two in the radial direction, so that a transparent area that passes through the axial direction of the sample 7 to be tested is left between the coating areas on the two surfaces.

[0046] The radial distance between the straight sides of the two sector-shaped areas is greater than or equal to the radial maximum dimension of the PDV probe 1 .

[0047] 2.2. A sub-micron-thick metal reflective film is coated on the fan-shaped area on the bullet-facing surface and the non-bullet-facing surface respectively.

[0048] Step 3, at least one PDV probe 1 is arranged in the coated area of ​​the non-ballistic surface not affected by the side rarefaction wave, in the non-coated area of ​​the non-ballistic surface not affected by the side rarefaction wave, and at one end of the non-ballistic surface of the transparent area, wherein the non-coated area refers to a place on the non-ballistic surface avoiding the transparent area and the coated area and corresponding to the coated area of ​​the ballistic surface.

[0049] Step 4: Use the light gas gun flat plate impact test device to impact the sample 7 from the projectile surface along the axial direction, and use each PDV probe 1 to obtain the particle velocity signals at the corresponding positions of the projectile surface and the non-projectile surface, as well as the velocity signals of the flying pieces, and then calculate the flatness and material wave velocity of the sample 7 to be tested. Specifically:

[0050] 4.1. The light gas gun flat plate impact test device is used to impact the sample 7 from the projectile surface along the axial direction, and the PDV probes 1 arranged in the coated area and the non-coated area of ​​the non-projectile surface respectively obtain the particle velocity signals at the corresponding positions of the non-projectile surface. At the same time, the PDV probe 1 arranged in the transparent area obtains the velocity signal of the flying pieces of the light gas gun flat plate impact test device.

[0051] 4.2. The flatness of the sample 7 to be tested is calculated by the waveform starting time point in the particle velocity signal at the corresponding positions of the coated area and the non-coated area of ​​the non-bullet-facing surface. The calculation method of the flatness tanθ of the sample 7 to be tested is:

[0052]

[0053] Among them, t1 is the waveform jump time point in the particle velocity signal of the non-coated area of ​​the non-projectile surface, t2 is the waveform jump time point in the particle velocity signal of the coated area of ​​the non-projectile surface, v is the speed of the flying piece of the light gas gun flat plate impact test device (i.e., impact speed), d is the distance between the PDV probe arranged in the coated area of ​​the non-projectile surface and the PDV probe arranged in the non-coated area of ​​the non-projectile surface, and θ is the inclination angle of the sample to be tested, that is, the angle between the axial direction of the sample to be tested and the flight direction of the flying piece.

[0054] 4.3. The wave velocity of the sample 7 to be tested is calculated by using the time difference between the starting points of the waveform in the particle velocity signal at the corresponding positions of the coated area and the non-coated area of ​​the non-bullet-facing surface.

[0055] The calculation method of the wave velocity D of the sample to be tested is:

[0056]

[0057] Wherein, h is the axial length of the sample 7 to be tested.

[0058] In the existing measurement method, the interface without coating can measure the signal inside the transparent sample and other interfaces, and the signals are mixed and difficult to distinguish. However, a transparent material parameter measurement method of this embodiment solves the problem of many clutter signals in transparent material measurement in the flat plate impact test, thereby improving the signal-to-noise ratio and test accuracy.

[0059] In this embodiment, multiple material parameters can be obtained through one experiment, and some parameters can be verified with each other, that is, the flying sheet velocity can verify the free interface particle velocity, and the two interface particle velocities can also be verified with each other, thereby improving the experimental efficiency and measurement accuracy.

[0060] This embodiment also provides a transparent material parameter measurement system, including a light gas gun flat plate impact test device, at least three PDV probes 1, and a data acquisition device 2.

[0061] The light gas gun flat plate impact test device comprises a high-pressure gas chamber 3, a gun barrel 4 installed at the outlet end of the high-pressure gas chamber 3, and a bullet 5 and a flying piece 6 installed in the gun barrel 4 in sequence; the bullet 5 is installed close to the outlet end of the high-pressure gas chamber 3; and the end of the gun barrel 4 away from the high-pressure gas chamber is used to install a sample 7 to be tested.

[0062] If there are three PDV probes 1, they are respectively installed in the coated area of ​​the non-bullet-facing surface of the sample 7 to be tested where it is not affected by the side rarefaction waves, in the non-coated area of ​​the non-bullet-facing surface where it is not affected by the side rarefaction waves, and at one end of the non-bullet-facing surface of the transparent area that passes through the axial direction of the sample 7 to be tested.

[0063] The data acquisition device 2 is connected to each PDV probe 1 to collect the parameter information obtained by the PDV probe 1, and finally calculates other relevant parameter information of the transparent material through the collected parameter information, such as the DU of the material. p Curves, etc.

[0064] The transparent material parameter measurement system of the present embodiment has high speed accuracy, high dynamic range, and high experimental efficiency, and therefore has strong versatility.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A method for measuring parameters of transparent materials, characterized in that: The following steps are involved: Step 1, prepare a sample to be tested; the sample to be tested is made of transparent material and is cylindrical, and the two bottom surfaces of the sample to be tested are defined as a projectile-facing surface and a non-projectile-facing surface; Step 2, dividing the coating area on the bullet-facing surface and the non-bullet-facing surface of the sample to be tested respectively, the coating areas on the two sides are staggered, and a transparent area that runs through the axial direction of the sample to be tested is left between the two, and then a layer of metal reflective film is coated in each coating area; Step 3, at least one PDV probe is arranged in the coating area of ​​the non-ballistic surface not affected by the side rarefaction wave, in the non-coating area of ​​the non-ballistic surface not affected by the side rarefaction wave, and at one end of the non-ballistic surface of the transparent area; the non-coating area refers to a part of the non-ballistic surface that avoids the transparent area and the coating area and corresponds to the coating area of ​​the ballistic surface; Step 4: Use the light gas gun flat plate impact test device to impact the sample to be tested axially from the projectile surface, and use each PDV probe to obtain the particle velocity signal at the corresponding position and the velocity signal of the flying piece, and then calculate the flatness and wave velocity of the sample to be tested.

2. The method for measuring parameters of transparent materials according to claim 1, characterized in that: Step 2 is as follows: 2.

1. The coating areas are divided on the bullet-facing surface and the non-bullet-facing surface of the sample to be tested, respectively. The coating areas on the bullet-facing surface and the non-bullet-facing surface are respectively fan-shaped areas with an angle of 180°. The arc edges of the two fan-shaped areas are arranged symmetrically along the radial direction and coincide with the circular edges of the surfaces on which they are located, so that the coating areas on the two surfaces are arranged in a staggered manner; the straight edges of the two fan-shaped areas are arranged in parallel, and a distance is left between the two radial directions, so that a transparent area that runs through the axial direction of the sample to be tested is left between the coating areas on the two surfaces; 2.

2. A layer of metal reflective film is coated on the fan-shaped area on the bullet-facing surface and the non-bullet-facing surface respectively.

3. The method for measuring parameters of transparent materials according to claim 2, characterized in that: In step 2.1, the radial distance between the straight sides of the two sector-shaped areas is greater than or equal to the radial maximum dimension of the PDV probe.

4. The method for measuring parameters of a transparent material according to any one of claims 1 to 3, characterized in that: Step 4 is as follows: 4.

1. Use a light gas gun flat plate impact test device to impact the sample from the projectile surface along the axial direction, and use the PDV probes arranged in the coated area and non-coated area of ​​the non-projectile surface to obtain the particle velocity signals at the corresponding positions respectively, and use the PDV probes arranged in the transparent area to obtain the velocity signals of the flying pieces of the light gas gun flat plate impact test device; 4.

2. The flatness of the sample to be tested is calculated by the waveform starting time point in the particle velocity signal at the corresponding positions of the coating area and the non-coating area; 4.

3. The wave velocity of the sample to be tested is calculated by using the time difference between the starting points of the waveform in the particle velocity signal at the corresponding positions of the coated area and the non-coated area.

5. The method for measuring parameters of transparent materials according to claim 4, characterized in that: In step 4.2, the calculation method of the flatness tanθ of the sample to be tested is: Among them, t1 is the waveform jump time point in the particle velocity signal of the non-coated area of ​​the non-projectile surface, t2 is the waveform jump time point in the particle velocity signal of the coated area of ​​the non-projectile surface, v is the impact velocity of the flying piece of the light gas gun flat plate impact test device, d is the distance between the PDV probe arranged in the coated area of ​​the non-projectile surface and the PDV probe arranged in the non-coated area of ​​the non-projectile surface, and θ is the angle between the axial direction of the sample to be tested and the flight direction of the flying piece.

6. The method for measuring parameters of transparent materials according to claim 5, characterized in that: In step 4.3, the calculation method of the wave velocity D of the sample to be tested is: Where h is the axial length of the sample to be tested.

7. A transparent material parameter measurement system, used to implement the transparent material parameter measurement method according to any one of claims 1 to 6, characterized in that: The device comprises a light gas gun flat plate impact test device, at least three PDV probes (1), and a data acquisition device (2); The light gas gun flat plate impact test device comprises a high-pressure gas chamber (3), a gun barrel (4) installed at the outlet end of the high-pressure gas chamber (3), and a bullet (5) and a flying piece (6) installed in the gun barrel (4) in sequence; the bullet (5) is installed near the outlet end of the high-pressure gas chamber (3); the end of the gun barrel (4) away from the high-pressure gas chamber is used to install a sample to be tested (7); The PDV probes (1) are respectively installed at a location in the coating area of ​​the non-bullet-facing surface of the sample (7) to be tested that is not affected by the side rarefaction wave, a location in the non-coating area of ​​the non-bullet-facing surface that is not affected by the side rarefaction wave, and an end of the non-bullet-facing surface of the transparent area that passes through the axial direction of the sample to be tested; The data acquisition device (2) is respectively connected to each PDV probe (1) and is used to collect parameter information acquired by the PDV probe (1).

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