Porous metal foil heating body for neutron scattering experiment

Abstract

The utility model relates to the field of neutron scattering, in particular to a porous metal foil heating body for a neutron scattering experiment. The porous metal foil heating body comprises a first electrode plate, a second electrode plate, a niobium tube cover, a ceramic tube sleeve, a porous niobium foil, a niobium ring and a ceramic cover; the first electrode plate is welded at the top of the niobium tube cover; the second electrode plate is arranged below the first electrode plate, sleeves the niobium tube cover and is connected with the first electrode plate through a bolt; a ceramic tube sleeve is arranged between the first electrode plate and the second electrode plate; two layers of porous niobium foils are welded on the inner surface of the niobium tube cover, and niobium rings are welded at the bottoms of the porous niobium foils; a ceramic cover is arranged at the bottom of the niobium ring; by optimizing the structural design, the experimental background is reduced, the heating efficiency and the uniformity of the sample temperature are improved, the service life is remarkably prolonged, the experimental flexibility is enhanced, and due to the advantages, the device has wide application prospects and important practical value in the field of neutron scattering.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of neutron scattering, in particular to a porous metal foil heating body for neutron scattering experiments. BACKGROUND

[0002] Neutrons, due to their unique properties such as being uncharged, strong penetration, and having a magnetic moment, have become an ideal tool for exploring the microscopic structure and dynamics of matter. Neutron scattering experiments, as a method of using the characteristics of neutron interactions with matter to study the microscopic structure and dynamics of matter, are based on the nuclear force interaction of neutrons with atomic nuclei and the interaction of neutron magnetic moments with the magnetic properties of matter. When neutrons penetrate matter, they scatter, revealing the internal structure and dynamic characteristics of matter.

[0003] In neutron scattering experiments, in order to enhance the practical significance of the experiment, it is often necessary to provide an ultra-high temperature environment for the sample. Metal foil heating bodies, as key heat sources for ultra-high temperature sample environments in neutron scattering experiments, can typically provide a high temperature range of 1200℃-1600℃ and are widely used in scattering experiments at various types of spallation neutron sources. During the experiment, the porous niobium foil heating body generates heat through high current, and the sample is suspended in the center of the heating body. The neutron beam penetrates the heating body and hits the sample, interacting with the atomic nuclei in the sample and causing neutron scattering. Subsequently, the wave vector and energy of the scattered neutrons are measured using a detector, and the collected data is processed and analyzed through correction, normalization, fitting, etc., thereby revealing the microscopic structure and dynamic characteristics of the sample.

[0004] However, traditional metal foil heating bodies have many shortcomings during the experiment. First, the high experimental background affects the accuracy of the experimental data. Second, these heating bodies are prone to damage in high-temperature environments, especially in operating environments above 1400℃, and may be damaged after about 20 cycles. Therefore, it is necessary to optimize the structure of the metal foil heating body to reduce the experimental background, improve the heating efficiency, and prolong the service life. SUMMARY

[0005] To solve the above problems, the present application aims to provide a porous metal foil heating body for neutron scattering experiments to reduce the experimental background, improve the heating efficiency, and prolong the service life.

[0006] The technical scheme adopted by the present application is: a porous metal foil heating body for neutron scattering experiment, comprising a first electrode sheet, a second electrode sheet, a niobium tube cover, a ceramic tube sleeve, a porous niobium foil, a niobium ring and a ceramic cover; the first electrode sheet is welded on the top of the niobium tube cover; the second electrode sheet is arranged below the first electrode sheet and is sleeved on the niobium tube cover and connected with the first electrode sheet through bolts; the ceramic tube sleeve is arranged between the first electrode sheet and the second electrode sheet; two layers of porous niobium foils are welded on the inner surface of the niobium tube cover, and the niobium ring is welded on the bottom of the porous niobium foil; the bottom of the niobium ring is provided with the ceramic cover.

[0007] The material of the first electrode sheet and the second electrode sheet is copper.

[0008] The first electrode sheet is welded on the top of the niobium tube cover, and the second electrode sheet is connected with the first electrode sheet through bolts and nuts.

[0009] The material of the niobium tube cover is niobium, which has two layers of inner and outer layers, and the thickness is 0.8-2mm, the inner diameter of the inner layer is 40-60mm, and the inner diameter of the outer layer is 50-70mm.

[0010] The material of the porous niobium foil is niobium, which has two layers of inner and outer layers, the inner diameter of the inner layer is 40-60mm, the inner diameter of the outer layer is 50-70mm, and the thickness is less than 0.1mm.

[0011] Two key-shaped holes are formed in the middle of the porous niobium foil, the length is 50-60mm, and the width is 15-20mm; there are 7 rows and 10 columns of small holes arranged in the circumferential direction above and below the hole, the diameter of the small hole is less than 10mm, and the distance between the closest small hole in the middle and the hole is 30-40mm.

[0012] The material of the niobium ring is niobium, the thickness is 5-10mm, the inner diameter is 40-60mm, and the outer diameter is 50-60mm.

[0013] The porous niobium foil is welded on the side surface of the niobium ring, and a threaded through hole is formed in the bottom of the niobium ring for connecting the ceramic cover at the bottom.

[0014] The material of the ceramic cover is silicon carbide, and a threaded through hole is formed in the bottom for connecting the niobium ring above.

[0015] The heating body generates heat through the current heat effect, the current enters from the second electrode sheet, flows through the outer layer of the niobium tube cover, the outer layer of the porous niobium foil, the niobium ring, the inner layer of the porous niobium foil, the inner layer of the niobium tube cover, and finally flows out from the first electrode sheet.

[0016] The beneficial effects of the present application are: the porous metal foil heating body for neutron scattering experiment of the present application, by optimizing the structure design, not only reduces the experimental background, improves the heating efficiency and the uniformity of sample temperature, but also significantly prolongs the service life, and enhances the flexibility of the experiment, these advantages make the present application have wide application prospect and important practical value in the field of neutron scattering.

[0017] Mainly embodied in the following aspects:

[0018] (I) Reduce the experimental background: by designing a special opening structure on the neutron beam channel, the porous metal foil heating body of the present application can significantly reduce the scattering and absorption of neutron beam when passing through the heating body, thereby effectively reducing the experimental background. This not only improves the precision and reliability of neutron scattering experiment, but also makes the experimental data more accurate and easy to analyze.

[0019] (II) Improve the heating efficiency: the present application adopts double-layer porous niobium foil design, which increases the resistance and current density when the current passes through, thereby improving the heating efficiency of the heating body. At the same time, the use of ceramic cover reduces the heat leakage between the heating body and the sample, further improving the efficiency of radiant heating. This design enables the sample to reach the required high temperature faster and more uniformly, thereby improving the efficiency of the experiment.

[0020] (III) Prolong the service life: the heating body structure of the present application is more solid and durable, especially in high temperature environment. The use of niobium tube cover and niobium ring, as well as the heat insulation protection of ceramic tube sleeve and ceramic cover, enhances the anti-oxidation and breaking ability of the heating body in high temperature environment. This enables the heating body to work more times at a high temperature of 1400℃ or above without damage, thereby significantly prolonging the service life.

[0021] (Four) Enhance the flexibility of the experiment: the porous metal foil heating body of the present application is designed flexibly, easy to install and disassemble. At the same time, by adjusting the current size, the temperature of the sample can be accurately controlled to meet the needs of different types of neutron scattering experiments. This flexibility enables the present application to be widely used in various neutron scattering experiment occasions, improving the adaptability and practicality of the experiment. BRIEF DESCRIPTION OF DRAWINGS

[0022] Fig. 1 is a schematic diagram of the overall structure of the present application;

[0023] Fig. 2 is a schematic diagram of the overall structure of the present application;

[0024] Fig. 3 is a schematic diagram of the overall structure of the present application and a schematic diagram of the current movement direction.

[0025] Brief Description of Drawings: Wherein: 1-First electrode sheet, 2-Second electrode sheet, 3-Niobium tube cover, 4-Ceramic tube cover, 5-Porous niobium foil, 6-Niobium ring, 7-Ceramic cover. DETAILED DESCRIPTION

[0026] The specific embodiments of the porous metal foil heating body for neutron scattering experiments of the present application will be described in detail below with reference to the accompanying drawings, to further illustrate the principles and advantages of the present application. It should be noted that the following examples are only preferred embodiments of the present application, and are not limiting to the present application, and those skilled in the art can make other adjustments or improvements according to the teaching of the present application, which still belong to the protection scope of the present application.

[0027] As shown in Figs. 1 to 3 The porous metal foil heating body for neutron scattering experiments of the present application mainly consists of a first electrode sheet 1, a second electrode sheet 2, a niobium tube cover 3, a ceramic tube cover 4, a porous niobium foil 5, a niobium ring 6, a ceramic cover 7 and a plurality of M6, M3 screws and nuts.

[0028] Specifically, the first electrode sheet 1 and the second electrode sheet 2 are made of copper, which has good electrical conductivity. The first electrode sheet 1 is welded on the top of the niobium tube cover 3, while the second electrode sheet 2 is sleeved on the niobium tube cover 3 and connected with the first electrode sheet 1 through the bolt and nut of M6, to ensure the close contact and good electrical conductivity between the two. Between the first electrode sheet 1 and the second electrode sheet 2, the ceramic tube cover 4 is placed to play the role of insulation and heat insulation.

[0029] The niobium tube cover 3 is made of niobium, and the total height of the niobium foil is 200-250mm, which has an inner and outer layer structure with a thickness of 1mm, an inner diameter of the inner layer of 50mm and an outer diameter of the outer layer of 60mm. The niobium tube cover 3 not only serves as a support structure of the heating body, but also as a part of the current passage.

[0030] The porous niobium foil 5 is the core part of the heating body, which is also made of niobium, and the total height of the porous niobium foil 5 is 200-250mm. The porous niobium foil 5 has an inner and outer layer, with an inner diameter of the inner layer of 50mm, an outer diameter of the outer layer of 60mm and a thickness of 0.05mm. Two key-shaped holes are opened in the middle of the porous niobium foil 5, with a length of 58mm and a width of 18mm. These openings are used to accommodate the neutron beam to reduce the influence of the heating body on the neutron beam, thereby reducing the experimental background. In addition, there are 7 rows and 10 columns of small holes with a diameter of 5mm arranged circumferentially above and below the openings of the porous niobium foil 5. The increase of these small holes further improves the heating efficiency and uniformity of the heating body.

[0031] The material of the niobium ring 6 is also niobium, with a thickness of 5 mm, an inner diameter of 50 mm, and an outer diameter of 60 mm. The porous niobium foil 5 is welded on the side of the niobium ring 6 to form a stable connection. Four M3 threaded holes are opened at the bottom of the niobium ring 6 for connecting the bottom ceramic cover 7.

[0032] The material of the ceramic cover 7 is silicon carbide SiC, which has good high-temperature resistance and heat insulation capacity. Four M3 threaded holes are also opened at the bottom of the ceramic cover 7 for connecting with the niobium ring 6 through bolts. The addition of the ceramic cover 7 not only reduces the heat leakage between the heating body and the sample, improves the efficiency of radiant heating, but also further improves the uniformity of the sample temperature and effectively prolongs the service life of the heating body.

[0033] In actual use, the heating body of the present application will be loaded into a neutron scattering high-temperature furnace and hoisted onto a neutron scattering spectrometer for work. The sample is suspended on the central axis of the heating body through the sample rod, and the sample height is aligned with the opening height of the porous niobium foil 5, so that the neutron beam can accurately incident on the sample.

[0034] Before work, the high-temperature furnace needs to be sealed and vacuumed to below 10^-9 Kpa or an inert gas atmosphere is added to prevent the heating body from being oxidized and damaged at high temperature. Then, the cables are connected on the first electrode sheet 1 and the second electrode sheet 2 to provide high current. The current enters from the second electrode sheet 2, flows through the outer layer of the niobium tube cover 3, the outer layer of the porous niobium foil 5, the niobium ring 6, the inner layer of the porous niobium foil 5, the inner layer of the niobium tube cover 3, and finally flows out from the first electrode sheet 1. Because the resistance of the porous niobium foil 5 is large, the current density is also large, so a large amount of heat will be generated in this part. These heat is transmitted to the sample by heat radiation to achieve the purpose of heating the sample.

[0035] The neutron beam will pass through the neutron beam window of the high-temperature furnace and the opening of the porous niobium foil 5, and hit the sample to occur neutron scattering. The scattered neutrons will directly pass through the heating body and the high-temperature furnace and be collected by the outside detector. Through processing and analysis of the detected energy and wave vector, such as correction, normalization and fitting, the microstructure and dynamic characteristics of the sample can be explained.

[0036] In summary, the porous metal foil heating body for neutron scattering experiments has the advantages of high heating efficiency, long service life, low experimental background, etc., which can meet the needs of neutron scattering experiments for ultra-high temperature sample environment equipment, and improve the practical significance and accuracy of the experiment.

Claims

1. A multi-aperture metal foil heat emitter for neutron scattering experiments, characterized in that: The porous metal foil heating body comprises a first electrode sheet, a second electrode sheet, a niobium tube cover, a ceramic tube cover, a porous niobium foil, a niobium ring and a ceramic cover; the first electrode sheet is welded on the top of the niobium tube cover; the second electrode sheet is arranged below the first electrode sheet and is sleeved on the niobium tube cover and connected with the first electrode sheet through bolts; the ceramic tube cover is arranged between the first electrode sheet and the second electrode sheet; two layers of the porous niobium foil are welded on the inner surface of the niobium tube cover, and the niobium ring is welded on the bottom of the porous niobium foil; the bottom of the niobium ring is provided with the ceramic cover.

2. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The material of the first electrode sheet and the second electrode sheet is copper.

3. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The first electrode sheet is welded on the top of the niobium tube cover, and the second electrode sheet is connected with the first electrode sheet through bolts and nuts.

4. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The material of the niobium tube cover is niobium, which has two layers of inner and outer layers, and the thickness is 0.8-2mm, the inner diameter of the inner layer is 40-60mm, and the inner diameter of the outer layer is 50-70mm.

5. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The material of the porous niobium foil is niobium, which has two layers of inner and outer layers, the inner diameter of the inner layer is 40-60mm, the inner diameter of the outer layer is 50-70mm, and the thickness is less than 0.1mm.

6. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: Two key-shaped holes are arranged in the middle of the porous niobium foil, the length is 50-60mm, and the width is 15-20mm; 7 rows and 10 columns of small holes are arranged in the circumferential direction above and below the holes, the diameter of the small holes is less than 10mm, and the distance between the middle row of small holes and the middle of the hole is 30-40mm.

7. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The material of the niobium ring is niobium, the thickness is 5-10mm, the inner diameter is 40-60mm, and the outer diameter is 50-60mm.

8. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The porous niobium foil is welded on the side of the niobium ring, and a threaded through hole is arranged in the bottom of the niobium ring for connecting the ceramic cover on the bottom.

9. The porous metal foil heat generator for a neutron scattering experiment according to claim 1, characterized by: The material of the ceramic cover is silicon carbide, and a threaded through hole is arranged in the bottom for connecting the niobium ring above.

10. The multi-aperture metal foil heat generator for neutron scattering experiments according to any one of claims 1-9, characterized in that: The heating body generates heat through the current heat effect, the current enters from the second electrode sheet, flows through the outer layer of the niobium tube cover, the outer layer of the porous niobium foil, the niobium ring, the inner layer of the porous niobium foil, the inner layer of the niobium tube cover, and finally flows out from the first electrode sheet.

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