Reflection type polycrystalline dynamic X-ray diffraction device based on laser device

Abstract

The invention relates to the technical field of X-ray diffraction diagnosis, and provides a reflective polycrystalline dynamic X-ray diffraction device based on a laser device, comprising: a rear substrate; the front shielding plate is fixedly mounted at the top of the rear base body, and a through collimation hole is formed in the front shielding plate; the two side shielding plates are fixedly mounted on the two sides of the rear base body respectively; the backlight target is fixedly mounted at the top of the front shielding plate; the two imaging assemblies correspond to the two side shielding plates in a one-to-one mode, each imaging assembly comprises an IP plate and a filter disc, the IP plates and the filter discs are connected with the rear base body in a clamped mode, and the filter discs are located on the inner sides of the IP plates; and the sample table is fixedly installed on the inner wall of the rear base body, the sample table is used for placing a sample, the sample table is aligned with the collimation hole, and the sample table, the backlight target and the IP plate are located on the same focusing circle.

Description

Technical Field

[0001] This invention relates to the field of X-ray diffraction diagnostic technology, and specifically to a reflective polycrystalline dynamic X-ray diffraction device based on a laser device. Background Technology

[0002] Under extreme loads such as high-speed impact and detonation, crystalline materials are prone to atomic structure rearrangement (i.e., "structural phase transition"). This phase transition leads to significant abrupt changes in multiple aspects of the material's mechanical properties (such as strength), optical properties (such as transparency), and electrical properties (such as conductivity), thereby affecting the propagation law of impact / detonation waves. Therefore, accurately capturing the critical time point of phase transition and characterizing the microstructure before and after the phase transition is of crucial significance for fundamental research in explosion mechanics and engineering applications (such as armor material design).

[0003] While transmission-based in-situ dynamic X-ray diffraction (DXRD) has made some progress, it suffers from two major bottlenecks due to its "X-rays penetrating the sample" technical principle: firstly, it cannot effectively measure high atomic number (high Z) materials (such as heavy elements like tantalum and lead); secondly, it is only suitable for thin samples with a thickness of a few micrometers (thick samples cause severe X-ray attenuation and signal distortion). Furthermore, the transmission configuration is susceptible to interference from stray X-rays and high-energy electrons generated by laser plasma, resulting in a low signal-to-noise ratio in the diffraction signal, making it difficult to meet the precise diagnostic requirements under ultra-high pressure conditions.

[0004] To overcome the above limitations, a new dynamic X-ray diffraction technique is urgently needed to achieve efficient characterization of thick samples and heavy element samples, and to improve the clarity and reliability of diffraction signals. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a laser-based reflective polycrystalline dynamic X-ray diffraction device that can efficiently characterize thick samples and heavy element samples, and improve the clarity and reliability of diffraction signals.

[0006] To achieve the above objectives, the present invention provides a reflective polycrystalline dynamic X-ray diffraction device based on a laser device, comprising:

[0007] Post-matrix;

[0008] A front shielding plate is fixedly installed on the top of the rear base, and a through-hole collimation hole is opened on the front shielding plate;

[0009] Two side shielding plates are fixedly installed on both sides of the rear base, respectively;

[0010] A backlight target, which is fixedly mounted on the top of the front shielding plate;

[0011] Two imaging components are provided, each corresponding to one of the two side shielding plates. Each imaging component includes an IP plate and a filter. Both the IP plate and the filter are snapped into the rear substrate, and the filter is located inside the IP plate.

[0012] A sample stage is fixedly installed on the inner wall of the rear substrate. The sample stage is used to place the sample, and the sample, the backlight target, and the IP plate are located on the same focusing circle.

[0013] Furthermore, the backlight target and the front shielding plate are fixedly connected by a target frame and a fixture.

[0014] Furthermore, the backlight target is made of zirconium, copper, iron or titanium, the backlight target has a hollow hole, the target frame is made of PMMA, and the fixture is made of aluminum.

[0015] Furthermore, the sample stage is made of tantalum, tungsten, or lead.

[0016] Furthermore, the front shielding plate is made of tantalum-tungsten alloy, and the filter is made of hydrocarbon material or light metal.

[0017] Furthermore, the side shielding plate is made of tantalum-tungsten alloy.

[0018] Furthermore, it also includes a focusing and aiming assembly, which is fixedly connected to the rear substrate via an optical fiber fixing stage. The focusing and aiming assembly is externally connected to an optical fiber for measuring the wave profile velocity of the sample and calculating the pressure state of the sample.

[0019] Furthermore, the rear substrate, the front shielding plate, the side shielding plate, the IP plate, and the filter are in close contact.

[0020] The beneficial effects of this invention are:

[0021] 1. The present invention provides a laser-based reflective polycrystalline dynamic X-ray diffraction device that can be used with thick samples exceeding several micrometers in thickness, eliminating the need to prepare ultrathin samples and reducing the difficulty of sample acquisition; at the same time, it is compatible with high atomic number (high Z) material samples, breaking through the application limitations of transmission technology and achieving efficient characterization of thick samples and heavy element samples.

[0022] 2. The present invention provides a reflective polycrystalline dynamic X-ray diffraction device based on a laser device. The thick sample itself can attenuate some stray signals. With the multiple anti-interference design of the front shielding plate, side shielding plate and filter, the signal-to-noise ratio of the diffraction signal remains at a high level even under ultra-high pressure conditions, thereby improving the clarity and reliability of the diffraction signal. Attached Figure Description

[0023] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0024] Figure 2 for Figure 1 A front view structural diagram;

[0025] Figure 3 This is a schematic diagram of the three-dimensional structure of the front shielding plate;

[0026] Figure 4 This is a schematic diagram of the backlight target.

[0027] Reference numerals: 10-rear substrate, 20-front shielding plate, 21-collimation hole, 22-target holder, 23-fixer, 30-backlight target, 31-perforated hole, 41-IP plate, 50-sample stage, 51-sample, 60-focusing aiming assembly. Detailed Implementation

[0028] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0029] In this application, unless otherwise expressly specified and limited, the terms "connection" and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] In the description of this application, it should be understood that the terms "longitudinal", "horizontal", "level", "top", "bottom", "upper", "lower", "inner" and "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0031] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0032] like Figures 1-4As shown, the present invention provides a reflective polycrystalline dynamic X-ray diffraction device based on a laser device, including a rear substrate 10, a front shielding plate 20, a side shielding plate (not shown in the figure), a backlight target 30, an imaging component, and a sample stage 50.

[0033] The front shielding plate 20 is fixedly installed on the top of the rear base 10, and the front shielding plate 20 has a longitudinally penetrating collimation hole 21.

[0034] There are two side shielding plates, which are fixedly installed on both sides of the rear base 10.

[0035] The backlight target 30 is fixedly installed on the top of the front shielding plate 20.

[0036] There are four imaging components, each corresponding to one of the two side shielding plates, the rear substrate, and the front shielding plate. Each imaging component includes an IP plate 41 and a filter. Both the IP plate 41 and the filter are snapped into their corresponding shielding plates or rear substrates. The IP plate 41 receives X-rays and captures the diffraction pattern corresponding to the microstructure of the sample 51. The filter is located inside the IP plate 41 to reduce the influence of high-energy electrons, ensuring clearer imaging on the IP plate 41.

[0037] The sample stage 50 is fixedly mounted on the inner wall of the rear substrate 10, and is used to place the sample 51. The sample stage 50 is aligned with the collimation hole 21, and the sample stage 50, the backlight target 30, and the IP plate 41 are located on the same focusing circle. It is worth noting that the focusing circle is not a physical circle, but a theoretical circle; that is, the actual installation position of the IP plate 41 corresponding to the rear substrate is precisely aligned with the X-ray focusing area on this theoretical circle.

[0038] The specific operating steps for this device are as follows:

[0039] First, fix the backlight target 30, front shielding plate 20, and side shielding plate onto the rear substrate 10, and simultaneously snap the IP plate 41 and filter into place. Then, fix the device onto the laser equipment in the laser target chamber.

[0040] The second step is to evacuate the laser target chamber to a vacuum level better than 1×10⁻⁶. -2 Pa.

[0041] The third step involves moving the backlight target 30 to the center of the laser target chamber using a telephoto microscope, aligning the backlight target 30 with the laser focal point of the laser device, and then using a pre-pulse laser to guide the laser to the center of the backlight target 30.

[0042] Step 4: Adjust the laser parameters: focus less than 200μm, pulse width 1ns, energy greater than 3000J; adjust the loading laser parameters: use beam smoothing technology, distribute energy in a region with a diameter of 1.5mm, pulse width adjustable from 3-10ns, energy adjustable from 100-3000J.

[0043] Fifth step, start the laser equipment, the backlight laser bombards the backlight target 30 to generate X-rays, the X-rays act on the sample 51 through the collimation hole 21, and the diffracted X-rays reflected by the sample 51 are recorded by the IP plate 41.

[0044] The sixth step is to read the diffraction image on IP plate 41 and analyze the microstructure of sample 51 in combination with VISAR data.

[0045] In one embodiment, the backlight target 30 and the front shielding plate 20 are fixedly connected by a target frame 22 and a fixture 23, which respectively serve to support and fix the target.

[0046] In one embodiment, the backlight target 30 is made of metals such as zirconium, copper, iron, or titanium, which can stably emit X-rays. The backlight target 30 has perforated holes 31 for easy laser alignment. The target holder 22 is a rectangular column made of materials such as PMMA, whose main components are hydrocarbons, to prevent the laser from interacting with it and generating a large amount of stray X-rays and high-energy electrons. The fixture 23 is made of aluminum.

[0047] In one embodiment, the sample stage 50 is made of tantalum or lead. These heavy metal materials can block interference signals generated by the laser and reduce the influence of stray X-rays generated by the laser plasma on the diffraction signal.

[0048] In one embodiment, the front shield 20 is made of tantalum-tungsten alloy and is used to block stray X-rays and high-energy electrons. The filter is made of hydrocarbon materials or light metals.

[0049] In one embodiment, the side shield is made of tantalum-tungsten alloy and is used to block stray X-rays and high-energy electrons.

[0050] In one embodiment, a focusing and aiming assembly 60 is also included. The focusing and aiming assembly 60 is fixedly connected to the rear substrate 10 via an optical fiber fixing stage. The focusing and aiming assembly 60 is externally connected to an optical fiber for measuring the wave profile velocity of the sample 51 and calculating the pressure state of the sample 51.

[0051] In one embodiment, the rear substrate 10, the front shielding plate 20, the side shielding plate, the IP plate 41, and the filter are in close contact.

[0052] Specifically, the front shielding plate 20 is designed with a stepped shape to form an interlocking structure with the rear substrate 10 and the side shielding plates, further preventing stray X-rays from contaminating the X-ray diffraction image caused by the filtering.

[0053] Specifically, the side shielding plate is fixed to the rear base 10 through four screw holes with a diameter of 3.2 mm. The middle part is a groove with a thickness of 0.3 mm, which is used to position the IP plate 41 and the filter.

[0054] This device has the following technical advantages:

[0055] 1. Improved compatibility of sample 51: Thick samples 51 with a thickness of more than a few micrometers can be used, eliminating the need to prepare ultra-thin samples 51 and reducing the difficulty of obtaining samples 51; at the same time, it is compatible with high atomic number (high Z) material samples 51, breaking through the application limitations of transmission technology.

[0056] 2. Significantly optimized signal-to-noise ratio: The thick sample 51 itself can attenuate some stray signals. Combined with the anti-interference design of the front shielding plate 20 and the side shielding plate and filter made of tantalum-tungsten alloy material, the signal-to-noise ratio of the diffraction signal remains at a high level even under ultra-high pressure conditions.

[0057] 3. Additional interference suppression: The reflective geometry allows for the insertion of high-Z shielding materials into the main target, further eliminating plasma coronal noise and theoretically increasing the signal-to-noise ratio indefinitely.

[0058] 4. Comprehensive detector protection: Zero-order incident X-ray beams will exit the device directly along the reflection direction and will not irradiate IP plate 41, thus avoiding detector saturation failure.

[0059] 5. Thermodynamic state is easy to determine: The X-ray detection depth is only a few micrometers on the back surface of sample 51. The thermodynamic state (temperature, pressure) of sample 51 in this area is simple, which is convenient for accurate characterization and avoids the defect of complex overall state of sample 51 in transmission technology.

[0060] 6. Diverse research scenarios: The penetration depth can be changed by adjusting the X-ray energy, supporting the study of phase diagrams and phase transition dynamics under different compression dynamics such as single impact, multiple impact, and ramp compression.

[0061] 7. Specific depth research capability: By selecting backlight targets 30 with different materials / structures, the phase structure transformation at specific depths (such as micro-cracks) on the back surface of sample 51 can be studied in a targeted manner.

[0062] 8. Strong equipment compatibility: No large-scale laser equipment is required. Dynamic diffraction measurement of thick samples of heavy elements can be achieved on small-scale laser equipment, reducing experimental costs and equipment barriers.

[0063] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0064] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A reflection-type polychromatic dynamic X-ray diffraction apparatus based on a laser device, characterized by: It includes: a rear base; a front shielding plate fixedly installed on the top of the rear base, the front shielding plate having a collimating hole penetrating therethrough; two side shielding plates, each of which is fixedly installed on a side of the rear base; a backlit target fixedly installed on the top of the front shielding plate; two imaging assemblies, each of which corresponds to a side shielding plate, the imaging assembly including an IP plate and a filter, the IP plate and the filter being clamped with the rear base, the filter being located on the inner side of the IP plate; a sample stage fixedly installed on the inner wall of the rear base, the sample stage being used for placing a sample, the sample, the backlit target and the IP plate being located on the same focusing circle.

2. A reflection-type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 1, characterized in that: The backlit target and the front shielding plate are fixedly connected through a target holder and a fixer.

3. A reflection-type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 2, characterized in that: The material of the backlit target is zirconium, copper, iron or titanium, the backlit target having a hollow hole, the material of the target holder is PMMA, and the material of the fixer is aluminum.

4. A reflection-type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 3, characterized in that: The material of the sample stage is tantalum, tungsten or lead.

5. A reflection type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 1, characterized in that: The material of the front shielding plate is tantalum-tungsten alloy, and the material of the filter is carbon-hydrogen material or light metal.

6. A reflection type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 1, characterized in that: The material of the side shielding plate is tantalum-tungsten alloy.

7. A reflection type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 1, characterized in that: It also includes a focusing aiming assembly fixedly connected with the rear base through an optical fiber fixing table, the focusing aiming assembly circumscribing an optical fiber, being used for measuring the wave profile velocity of the sample and calculating the pressure state of the sample.

8. A reflection type polychromatic dynamic X-ray diffraction apparatus based on a laser device according to claim 1, characterized in that: The rear base, the front shielding plate, the side shielding plates, the IP plate and the filter are in close contact.

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