High-temperature-resistant praseodymium-silicon alloy for nuclear shielding, nuclear shielding material, and method for manufacturing same

Abstract

The application discloses a high-temperature-resistant praseodymium-silicon alloy for nuclear shielding, a nuclear shielding material and a manufacturing method thereof, and belongs to the field of nuclear engineering materials.The high-temperature-resistant praseodymium-silicon alloy for nuclear shielding comprises 0.5%-5% of Si according to weight ratio, and the balance is Pr and inevitable impurities.The alloy matrix structure is Pr, the grain size is 10-40 mu m, and Si2Pr particles are distributed in the matrix structure.By adding Si in the praseodymium-based alloy, the grain refinement is realized by using the high-melting-point compound Si2Pr formed by Si and Pr, the internal stress is dispersed and the alloy does not crack in the high-temperature hydrogenation process, and the cracking risk of the praseodymium-based alloy in the hydrogenation process is reduced.The alloy is suitable for manufacturing high-temperature-resistant nuclear shielding materials.

Description

Technical Field

[0001] This invention belongs to the field of nuclear engineering materials, specifically relating to a high-temperature praseodymium-silicon alloy for nuclear shielding, nuclear shielding materials, and their manufacturing methods. Background Technology

[0002] Praseodymium (Pr) is a low-activation material, exhibiting low induced radioactivity and low activity after neutron irradiation. PrH2 possesses excellent neutron shielding performance and a high decomposition temperature, allowing it to operate for extended periods in environments ranging from 600℃ to 1000℃, demonstrating better thermal stability compared to conventional shielding materials such as LiH, ZrH2, and TiH2. Furthermore, PrH2 has a BCC structure, offering better processing performance compared to materials with HCP structures. However, praseodymium is prone to high-temperature oxidation in high-temperature and aqueous environments, leading to significant corrosion problems. Additionally, PrH2 only shields fast neutrons, exhibiting weak shielding capabilities against thermal neutrons. While adding boron (B) can refine the grain size and improve thermal neutron absorption, the release of helium after neutron absorption introduces new irradiation swelling issues. Moreover, PrH2 has coarse grains and significant anisotropy, leading to stress concentration during hydrogen absorption due to differences in hydrogen absorption quantity and rate, resulting in hydrogen absorption cracking. Therefore, current conventional processes struggle to manufacture bulk PrH2 materials with engineering application value. Summary of the Invention

[0003] The purpose of this invention is to provide a high-temperature praseodymium-silicon alloy for nuclear shielding, which can be used to manufacture large-volume praseodymium-containing nuclear shielding materials. This invention also provides a method for manufacturing the high-temperature praseodymium-silicon alloy, a nuclear shielding material, and the method for manufacturing the same.

[0004] According to one aspect of the present invention, a high-temperature praseodymium-silicon alloy for nuclear shielding is provided, the alloy containing 0.5%-5% Si by weight, with the balance being Pr and unavoidable impurities, the matrix structure of the high-temperature praseodymium-silicon alloy for nuclear shielding being Pr with a grain size of 10μm-40μm, and Si2Pr particles distributed in the matrix structure.

[0005] By adding Si to praseodymium-based alloys, the high-melting-point compound Si2Pr formed by Si and Pr is used to refine the grains to 10~40μm, which disperses the internal stress and prevents cracking during high-temperature hydrogenation, thus solving the engineering bottleneck of hydrogen absorption cracking in coarse-grained praseodymium-based alloys. Si has the characteristics of low neutron activity, no radiation swelling, and no reaction with hydrogen, avoiding the radiation swelling problem caused by adding B.

[0006] Furthermore, in some embodiments, the high-temperature praseodymium-silicon alloy for nuclear shielding is composed of 0.5%-5% Si, no more than 15% Dy and / or no more than 15% Gd by weight, with the balance being Pr and unavoidable impurities. The addition of Dy and Gd can further improve the absorption performance for thermal neutrons and gamma rays.

[0007] Furthermore, in some embodiments, the high-temperature praseodymium-silicon alloy for nuclear shielding has a Si content of 0.5%-2.5%, a Dy content of no more than 10%, and a Gd content of no more than 10%. Controlling the Dy and Gd contents can improve the material's processing performance while maintaining good nuclear shielding performance.

[0008] According to another aspect of the present invention, a method for manufacturing a high-temperature praseodymium-silicon alloy for nuclear shielding is provided, for manufacturing the high-temperature praseodymium-silicon alloy for nuclear shielding provided in any of the foregoing embodiments. The method includes the following steps: Step a): Provide raw materials according to the composition of the high-temperature praseodymium-silicon alloy for nuclear shielding, melt them under inert gas protection, and cast them to obtain alloy ingots; Step b): The alloy ingot is hot-pressed or hot-forged at a temperature not lower than 800°C, and then hot-rolled at a temperature not lower than 850°C to obtain hot-rolled sheet. Step c): The hot-rolled sheet is subjected to cold rolling and annealing to obtain a high-temperature praseodymium-silicon alloy for nuclear shielding.

[0009] Furthermore, in some embodiments, in step a), a vacuum is first drawn until the pressure does not exceed 3 × 10⁻⁶. - 3 Pa, then an inert gas is introduced as a protective atmosphere, and the temperature is raised to not less than 1700°C at a heating rate of not less than 10°C / min, and held at that temperature for at least 10 minutes to obtain an alloy melt, which is then cast into an alloy ingot.

[0010] Furthermore, in some embodiments, step b) involves at least three hot rolling processes.

[0011] Furthermore, in some embodiments, in step c), at least three cold rolling processes are performed, and the annealing is carried out under vacuum or inert atmosphere protection.

[0012] According to another embodiment of the present invention, a method for manufacturing a nuclear shielding material is provided, the method using the high-temperature resistant praseodymium-silicon alloy for nuclear shielding provided in any of the foregoing embodiments as raw material, and comprising the following steps: The high-temperature praseodymium-silicon alloy for nuclear shielding is heated to 600℃-700℃ in a vacuum reaction vessel, and hydrogen gas of 0.25kPa-1.5kPa is introduced into the reaction vessel to fully hydrogenate the high-temperature praseodymium-silicon alloy for nuclear shielding; after vacuuming again and cooling, the finished nuclear shielding material is obtained.

[0013] Furthermore, in some embodiments, the high-temperature praseodymium-silicon alloy for nuclear shielding is manufactured using the manufacturing method of the high-temperature praseodymium-silicon alloy for nuclear shielding provided in any of the foregoing embodiments. Specifically, in step c), annealing is performed in a vacuum furnace, and after annealing, hydrogenation treatment is carried out in the same vacuum furnace.

[0014] According to another aspect of the present invention, a nuclear shielding material is provided, which is manufactured using the manufacturing method of the nuclear shielding material provided in the foregoing embodiments.

[0015] Furthermore, in some embodiments, the H:Pr value in the nuclear shielding material is 1.5-1.8. Attached Figure Description

[0016] Figure 1 A metallographic photograph of a praseodymium-silicon alloy in one embodiment; Figure 2 This is a micrograph of the nuclear shielding material in one embodiment.

[0017] The purpose of the above figures is to provide a detailed description of the invention so that those skilled in the art can understand the technical concept of the invention, and not to limit the invention. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0019] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment herein. The phrase appearing in various places in the specification does not necessarily refer to the same embodiment, nor is it limited to mutually exclusive, independent, or alternative embodiments. Those skilled in the art will understand that the embodiments herein can be combined with other embodiments without causing structural conflicts.

[0020] Nuclear shielding materials are used to shield neutron radiation generated in reactor cores and are crucial for the safety of nuclear facilities. Currently, commonly used nuclear shielding materials are mainly various metal hydrides, such as LiH, ZrH2, TiH2, and YH2. Among them, LiH, ZrH2, and TiH2 have decomposition temperatures below 800℃, making them suitable for conventional pressurized water reactors, but their high-temperature stability is insufficient for long-term service in newer reactors with higher operating temperatures, such as heat pipe microreactors. YH2 has better high-temperature stability, with a decomposition temperature exceeding 1200℃; however, YH2 exhibits an HCP structure at high temperatures, making it difficult to process. These factors collectively restrict the development of nuclear shielding materials.

[0021] Praseodymium (Pr) belongs to Group IIIB elements, just like yttrium. PrH2 also possesses good neutron shielding capabilities and exhibits low activation, resulting in low induced radioactivity after neutron irradiation. Furthermore, PrH2 has a BCC structure, offering better machinability. However, PrH2 can only shield fast neutrons, with weak shielding capabilities against thermal neutrons. While adding boron (B) can refine the grains and improve thermal neutron absorption, the release of helium after neutron absorption introduces new irradiation swelling problems. Moreover, PrH2 has coarse grains and significant anisotropy, leading to stress concentration during hydrogen absorption due to differences in hydrogen absorption quantity and rate, resulting in hydrogen absorption cracking. Therefore, a feasible process for manufacturing large-volume PrH2 is currently lacking.

[0022] To address the aforementioned problems in the prior art, one embodiment of the present invention provides a high-temperature praseodymium-silicon alloy for nuclear shielding. This alloy has a good, uniform, and fine microstructure, maintains structural integrity during hydrogenation, and exhibits low induced radioactivity and good neutron absorption capability.

[0023] Specifically, the praseodymium-silicon alloy comprises 0.5%-5% Si by weight, with the balance being Pr and unavoidable impurities. Its matrix is ​​Pr with a grain size of 10μm-40μm, and Si₂Pr particles are dispersed throughout the matrix. During the solidification process of the praseodymium-based alloy, Si₂Pr refines the grain size, ensuring that the fine and uniform grains prevent cracking during subsequent hot working and high-temperature hydrogenation, maintaining high strength and toughness. The grain-refined praseodymium-based alloy exhibits excellent hot workability and high-temperature resistance. Furthermore, the addition of silicon improves the corrosion resistance of the praseodymium-based alloy.

[0024] In a preferred embodiment, adding an appropriate proportion (not exceeding 15%) of Dy and / or Gd to the praseodymium-silicon alloy can further improve its shielding ability against thermal neutrons and gamma rays, thereby enhancing the performance of the hydrogenated nuclear shielding material. In a further preferred embodiment, the Si content in the praseodymium-silicon alloy is 0.5%-2.5%, the Dy content is not exceeding 10%, and the Gd content is not exceeding 10%, to ensure the alloy's machinability.

[0025] This praseodymium-silicon alloy can be manufactured using the method for manufacturing a high-temperature praseodymium-silicon alloy for nuclear shielding provided in another aspect of the present invention, the specific steps of which are as follows: Step a): Provide raw materials according to the composition ratio of praseodymium-silicon alloy, load the raw materials into a vacuum furnace, and first evacuate the furnace to a pressure not exceeding 3 × 10⁻⁶. -3 Pa is then introduced, followed by the introduction of an inert gas as a protective atmosphere, such as argon. Subsequently, the mixture is heated to above 1700°C at a heating rate of not less than 10°C / min and held at that temperature for at least 10 minutes to obtain an alloy melt, which is then cast into an alloy ingot.

[0026] Step b): The alloy ingot is hot-pressed or hot-forged at a temperature not lower than 800°C; then hot-rolled at a temperature not lower than 850°C to obtain hot-rolled sheet. In a preferred embodiment, the hot rolling process is repeated at least three times to fully improve the uniformity of the alloy structure and eliminate non-uniform solidification structure and macrosegregation.

[0027] Step c): The hot-rolled sheet is cold-rolled and annealed to obtain the praseodymium-silicon alloy product. In a preferred embodiment, the cold rolling process is repeated at least three times to ensure that the dimensions of the finished alloy are close to the design dimensions of the nuclear shielding material. Annealing is carried out under vacuum or inert gas protection, for example, pure argon can be used as the protective atmosphere.

[0028] Nuclear shielding material is prepared by hydrogenating praseodymium-silicon alloy: The high-temperature resistant praseodymium-silicon alloy for nuclear shielding is heated to 600℃-700℃ in a vacuum reaction vessel, and hydrogen gas at 0.25kPa-1.5kPa is introduced into the reaction vessel to fully hydrogenate the praseodymium-silicon alloy; after re-vacuuming and cooling, the finished nuclear shielding material is obtained. In specific embodiments, the hydrogenation time varies depending on the volume change of the praseodymium-silicon alloy, generally lasting several hours, for example, 5-10 hours, and usually not exceeding 24 hours. The specific time can be determined experimentally or calculated using simulation software. In a preferred embodiment, after cold rolling of the hot-rolled sheet, annealing is performed in a vacuum furnace. After annealing, the hydrogenation process is directly continued in the same vacuum furnace to prevent oxidation of the praseodymium-silicon alloy surface.

[0029] In a preferred embodiment, the H:Pr value of the nuclear shielding material manufactured by the above method is 1.5-1.8. This nuclear shielding material can operate stably for a long time in an environment of 600℃-1000℃ and is suitable for advanced reactor types such as space reactors, mobile reactors, or fusion reactors.

[0030] In the first embodiment, the manufacturing process of the nuclear shielding material is as follows: First, provide raw materials at a ratio of 0.5% Si and the balance Pr; load the raw materials into a vacuum furnace and evacuate to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, and held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot.

[0031] Next, the alloy ingot is hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet. The hot-rolled sheet is then subjected to three cold-rolling processes, followed by annealing with pure argon as the protective atmosphere to obtain the praseodymium-silicon alloy product. The alloy microstructure is as follows: Figure 1 As shown, the grain size is in the range of 10μm-40μm, and the grains are uniform and fine. Fine precipitates 1, which are composed of Si2Pr, are dispersed in the grains.

[0032] The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and its microstructure is as follows. Figure 2 As shown, the H:Pr ratio was measured to be approximately 1.5-1.8.

[0033] In the second embodiment, raw materials are first provided in a ratio of 1.0% Si and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon gas protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. The praseodymium-silicon alloy product was then hydrogenated at a hydrogen pressure of 2mmHg-10mmHg (0.267kPa-1.33kPa) to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0034] In the third embodiment, raw materials are first provided at a ratio of 2.0% Si and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0035] In the fourth embodiment, raw materials are first provided in a ratio of 3.0% Si and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0036] In the fifth embodiment, raw materials are first provided in a ratio of 4.0% Si and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0037] In the sixth embodiment, raw materials are first provided in a ratio of 5.0% Si and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0038] In the seventh embodiment, raw materials are first provided in a ratio of 1.0% Si, 10.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. The addition of Dy element improved the alloy's thermal neutron and gamma-ray shielding capabilities. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0039] In the eighth embodiment, raw materials are first provided in a ratio of 1.0% Si, 8.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared to the seventh embodiment, the amount of Dy element was reduced, but the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0040] In the ninth embodiment, raw materials are first provided in a ratio of 1.0% Si, 6.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared to the eighth embodiment, the amount of Dy element was further reduced, but the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0041] In the tenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 5.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon gas protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared to the ninth embodiment, the amount of Dy element was reduced, but the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0042] In the eleventh embodiment, raw materials are first provided in a ratio of 1.0% Si, 4.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. Despite a reduction in Dy element content, the alloy's thermal neutron and gamma-ray shielding capabilities remained significant. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0043] In the twelfth embodiment, raw materials are first provided in a ratio of 1.0% Si, 3.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. Despite a reduction in Dy element content, the alloy's thermal neutron and gamma-ray shielding capabilities remained significant. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0044] In the thirteenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 1.0% Dy, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Although the Dy element content was low, the alloy's thermal neutron and gamma-ray shielding capabilities were still significantly improved. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0045] In the fourteenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 10.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. The addition of Gd element improved the alloy's thermal neutron and gamma-ray shielding capabilities. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0046] In the fifteenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 8.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon gas protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared to the fourteenth embodiment, the amount of Gd element was reduced, but the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0047] In the sixteenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 6.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared to the fifteenth embodiment, the amount of Gd element was reduced, but the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0048] In the seventeenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 5.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared to the sixteenth embodiment, the amount of Gd element was reduced, but the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0049] In the eighteenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 4.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Despite a reduction in Gd content, the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0050] In the nineteenth embodiment, raw materials are first provided in a ratio of 1.0% Si, 3.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Despite a reduction in Gd content, the alloy's thermal neutron and gamma-ray shielding capabilities remained outstanding. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0051] In the twentieth embodiment, raw materials are first provided in a ratio of 1.0% Si, 1.0% Gd, and the balance Pr; the raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Although the Gd content was low, the alloy's thermal neutron and gamma-ray shielding capabilities were still significantly improved. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0052] In the twenty-first embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 10.0%, Gd 10.0%, and Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. The combined addition of Dy and Gd elements further improved the alloy's thermal neutron and gamma-ray shielding capabilities. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0053] In the twenty-second embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 8.0%, Gd 8.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. Compared to the twenty-first embodiment, the amounts of Dy and Gd were reduced, but the combined addition still significantly improved the shielding ability against thermal neutrons and gamma rays. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0054] In the twenty-third embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 6.0%, Gd 6.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. Compared to the twenty-second embodiment, the amounts of Dy and Gd were reduced, but the combined addition still significantly improved the shielding ability against thermal neutrons and gamma rays. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0055] In the twenty-fourth embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 5.0%, Gd 5.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Compared with the twenty-third embodiment, the amounts of Dy and Gd were reduced, but the combined addition still significantly improved the shielding ability against thermal neutrons and gamma rays. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0056] In the twenty-fifth embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 5.0%, Gd 5.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon gas was introduced as a protective atmosphere, and the mixture was heated to 1700°C at a rate of 10°C / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800°C, followed by three hot-rolling processes at a hot rolling temperature of 850°C to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed with pure argon gas as a protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. With the same composition as in Example 24, the combined addition of Dy and Gd significantly improved the shielding ability against thermal neutrons and gamma rays. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0057] In the twenty-sixth embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 4.0%, Gd 4.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. Although the amounts of Dy and Gd were reduced, their combined addition still significantly improved the shielding ability against thermal neutrons and gamma rays. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0058] In the twenty-seventh embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 3.0%, Gd 3.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at a hot rolling temperature of 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within it. Although the amounts of Dy and Gd were reduced, their combined addition still significantly improved the shielding ability against thermal neutrons and gamma rays. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0059] In the twenty-eighth embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 2.0%, Gd 2.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3 Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Although the addition of Dy and Gd was relatively low, it still had a good effect on improving the alloy's thermal neutron and gamma-ray shielding capabilities. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0060] In the twenty-ninth embodiment, raw materials are first provided in the following proportions: Si 1.0%, Dy 1.0%, Gd 1.0%, with Pr as the balance. The raw materials are then loaded into a vacuum furnace and evacuated to a pressure not exceeding 3 × 10⁻⁶. -3Pa; then, high-purity argon was introduced as a protective atmosphere, and the mixture was heated to 1700℃ at a rate of 10℃ / min, held at that temperature for 10 min to obtain an alloy melt; the alloy melt was then cast into an alloy ingot. Next, the alloy ingot was hot-pressed at 800℃, followed by three hot-rolling processes at 850℃ to obtain a hot-rolled sheet; the hot-rolled sheet was then cold-rolled three times, and annealed under a pure argon protective atmosphere to obtain the praseodymium-silicon alloy product. Testing showed that the alloy grain size was in the range of 10μm-40μm, with uniform and fine grains, and fine Si2Pr precipitates dispersed within. Although the addition of Dy and Gd was relatively low, it still had a good effect on improving the alloy's thermal neutron and gamma-ray shielding capabilities. The praseodymium-silicon alloy product was hydrogenated to obtain a nuclear shielding material with PrH2 as the main component, and the H:Pr ratio was measured to be approximately 1.5-1.8.

[0061] In the thirtieth embodiment, for embodiments seven to twenty-nine, the silicon content in the raw material preparation stage can be 0.5%, 1.5%, 2.0%, 3.0%, 4.0%, or 5.0%. By controlling the Si content within the range of 0.5-5.0%, the praseodymium, silicon, Dy, and Gd elements are rationally regulated. Si and Pr form a high-melting-point compound Si2Pr, and Dy and Gd are distributed at the grain boundaries. The resulting alloy grain size is in the range of 10μm-40μm, achieving grain refinement. The H:Pr ratio of the hydrogenated product is approximately 1.5-1.8. By adding alloying elements to the praseodymium matrix, the oxidation resistance of the praseodymium alloy is significantly improved, and the cracking problem caused by oxidation during the praseodymium hydrogenation process is mitigated. This process refines the grains, improves physical and mechanical properties, and fixes hydrogen.

[0062] In the thirty-first embodiment, for embodiments seven to twenty-nine, during the raw material preparation stage, the content of Dy can be 11.0%, 12.0%, 13.0%, 14.0%, or 15.0%, and the content of Gd can be 11.0%, 12.0%, 13.0%, 14.0%, or 15.0%. The higher amounts of Dy and Gd elements significantly improve the thermal neutron and gamma-ray shielding ability of the praseodymium-based alloy. The resulting alloy has a grain size in the range of 10μm-40μm, with uniform and fine grains. Praseodymium and silicon form a high-melting-point compound Si2Pr, and the H:Pr ratio of the hydrogenated product is approximately 1.5-1.8.

[0063] The praseodymium-silicon alloys provided in the above embodiments have uniform and fine grains, which can prevent stress concentration, maintain structural integrity, and avoid cracking during deformation processing and subsequent hydrogenation processing. The addition of Si can also improve the corrosion resistance of the material to a certain extent and inhibit the oxidation tendency of Pr in high-temperature and water environments. The nuclear shielding material obtained after hydrogenation processing has a uniform distribution of hydrogen elements without obvious compositional gradient, and the material as a whole has high strength and toughness. Among them, Examples 8 and 15 have better mechanical properties. The praseodymium-silicon alloy obtained in Example 8 has a hardness of 80.7 HV, and the praseodymium-silicon alloy obtained in Example 15 has a hardness of 68.1 HV, exhibiting good strength. After hydrogenation treatment, the structure remains intact, and no cracks appear.

[0064] The nuclear shielding material provided in the above embodiments can operate stably for a long time in an environment of 600℃-1000℃, and is suitable for advanced reactors such as space reactors, mobile reactors and fusion reactors.

[0065] The purpose of the above embodiments is to provide a further detailed description of the present invention in conjunction with the accompanying drawings, so that those skilled in the art can understand the technical concept of the present invention. Within the scope of the present invention, optimization and equivalent substitution of the technical features involved, as well as combination of implementation methods in different embodiments without conflict, all fall within the protection scope of the present invention.

Claims

1. A high-temperature praseodymium-silicon alloy for nuclear shielding, characterized in that, The nuclear shielding high-temperature praseodymium-silicon alloy matrix comprises 0.5%-5% Si by weight, with the balance being Pr and unavoidable impurities. The matrix has a Pr grain size of 10μm-40μm and contains Si2Pr particles.

2. The high-temperature praseodymium-silicon alloy for nuclear shielding according to claim 1, characterized in that, The high-temperature praseodymium-silicon alloy used for nuclear shielding is composed of 0.5%-5% Si, no more than 15% Dy and / or no more than 15% Gd by weight, with the balance being Pr and unavoidable impurities.

3. The high-temperature praseodymium-silicon alloy for nuclear shielding according to claim 2, characterized in that, The high-temperature praseodymium-silicon alloy used for nuclear shielding has a Si content of 0.5%-2.5%, a Dy content of no more than 10%, and a Gd content of no more than 10%.

4. A method for manufacturing a high-temperature praseodymium-silicon alloy for nuclear shielding, characterized in that, The method for manufacturing a high-temperature praseodymium-silicon alloy for nuclear shielding as described in any one of claims 1 to 3 includes the following steps: Step a): Provide raw materials according to the composition of the high-temperature praseodymium-silicon alloy for nuclear shielding, melt them under inert gas protection, and cast them to obtain alloy ingots; Step b): The alloy ingot is hot-pressed or hot-forged at a temperature not lower than 800°C, and then hot-rolled at a temperature not lower than 850°C to obtain hot-rolled sheet. Step c): The hot-rolled sheet is subjected to cold rolling and annealing to obtain a high-temperature praseodymium-silicon alloy for nuclear shielding.

5. The method for manufacturing high-temperature praseodymium-silicon alloy for nuclear shielding according to claim 4, characterized in that, In step a), a vacuum is first drawn until the pressure does not exceed 3 × 10⁻⁶. -3 Pa, then an inert gas is introduced as a protective atmosphere, and the temperature is raised to not less than 1700°C at a heating rate of not less than 10°C / min, and held at that temperature for at least 10 minutes to obtain an alloy melt, which is then cast into an alloy ingot.

6. The method for manufacturing the high-temperature praseodymium-silicon alloy for nuclear shielding according to claim 4, characterized in that, In step b), at least three hot rolling processes are performed.

7. The method for manufacturing high-temperature praseodymium-silicon alloy for nuclear shielding according to claim 4, characterized in that, In step c), at least three cold rolling processes are performed, and the annealing is carried out under vacuum or inert atmosphere protection.

8. A method for manufacturing a nuclear shielding material, characterized in that, Using the high-temperature resistant praseodymium-silicon alloy for nuclear shielding as described in any one of claims 1 to 3 as the raw material, and comprising the following steps: The high-temperature praseodymium-silicon alloy for nuclear shielding is heated to 600℃-700℃ in a vacuum reaction vessel, and hydrogen gas of 0.25kPa-1.5kPa is introduced into the reaction vessel to fully hydrogenate the high-temperature praseodymium-silicon alloy for nuclear shielding; after vacuuming again and cooling, the finished nuclear shielding material is obtained.

9. The method for manufacturing nuclear shielding material according to claim 8, characterized in that, The high-temperature praseodymium-silicon alloy for nuclear shielding is manufactured using the manufacturing method for high-temperature praseodymium-silicon alloy for nuclear shielding as described in any one of claims 4 to 7; in step c), annealing is performed in a vacuum furnace, and after annealing, hydrogenation treatment is performed in the same vacuum furnace.

10. A nuclear shielding material, characterized in that, It is manufactured using the manufacturing method of the nuclear shielding material as described in claim 8.

11. The nuclear shielding material according to claim 10, characterized in that, The H:Pr value in the nuclear shielding material is 1.5-1.8.

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