Preparation device and method of metal-based hydride shielding material

Abstract

The invention discloses a preparation device of a metal-based hydride shielding material, the device comprises an alloy smelting chamber, a hydrogenation chamber and a high-pressure chamber, an induction smelting furnace and a tungsten crucible are arranged in the alloy smelting chamber, a hydrogenation experiment table and a heating device are arranged in the hydrogenation chamber, and a hydrogen inlet and a hydrogen outlet are further formed in the hydrogenation chamber; an upper pressure head and a lower pressure head are arranged in the high-pressure chamber, the invention further discloses a preparation method of the metal-based hydride shielding material, and the preparation method comprises the following steps: 1, smelting; 2, hydrogenation crushing; 3, cold press molding; and 4, performing multi-stage pressure-controlled hydrogenation sintering to obtain the metal-based hydride shielding material. According to the invention, the key procedures of alloy smelting, hydrogenation crushing, cold press molding, hydrogenation sintering and the like are integrated in an integrated and multi-chamber device, so that the high hydrogen content and the component uniformity of the metal-based hydride shielding material are ensured, the problem of cracking in the traditional block hydrogenation process is effectively solved, and the method is suitable for preparing the metal-based shielding material.

Description

Technical Field

[0001] This invention belongs to the field of shielding material processing technology, specifically relating to a device and method for preparing a metal-based hydride shielding material. Background Technology

[0002] With the development of new nuclear reactors, micro and mobile reactors, and other technologies, extremely stringent requirements have been placed on neutron shielding materials, including lightweighting, high temperature resistance, and long-term stability of structure and shielding performance. Traditional polymer and cement shielding materials are difficult to operate stably under high temperature / high radiation conditions, and cannot balance quality and shielding efficiency. To simultaneously meet the requirements of efficient moderation, strong absorption, and high temperature resistance, metal-based hydride composite materials have become the development direction of the next generation of shielding materials. By synergistically combining lightweight, high-hydrogen-content metals (such as Zr, Y, Ti, Hf) with high-neutron-absorbing elements (Gd, Sm, Dy, etc.), excellent neutron moderation and absorption capabilities are introduced, and the overall hydrogen content of the material is increased through a hydrogenation process, thereby achieving the goal of low density and high shielding efficiency.

[0003] In materials preparation, the hydrogenation process of metallic materials is usually accompanied by significant volume expansion. Direct hydrogenation of bulk metals easily generates enormous internal stresses within the material, leading to problems such as cracking, pulverization, and even structural disintegration, making it difficult to prepare shielding components with stable performance and complex dimensions or shapes. How to effectively control the volume expansion effect and internal stress during hydrogenation to achieve the preparation of high-quality bulk materials is a key technical challenge restricting the application of such materials. Furthermore, the preparation process involves multiple steps in high-temperature, vacuum, or hydrogen environments. Traditional discrete equipment operation is not only cumbersome, but materials are also susceptible to air oxidation contamination during transfer between different devices, affecting the quality of the final product. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a preparation apparatus for metal-based hydride shielding materials, addressing the shortcomings of the prior art. This apparatus integrates key processes such as alloy melting, hydrogenation crushing, cold pressing, and hydrogenation sintering into a single, multi-chamber device. The entire preparation process can be carried out continuously without disrupting the vacuum or protective atmosphere, avoiding oxidation and contamination caused by intermediate products contacting air, and ensuring the high purity and high performance of the final material.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a preparation device for metal-based hydride shielding materials, characterized in that the device includes a sealed alloy melting chamber, a hydrogenation chamber and a high-pressure chamber that are connected in sequence. The alloy melting chamber is equipped with an induction melting furnace and a tungsten crucible. The hydrogenation chamber is equipped with a hydrogenation experimental platform, and a heating component is provided on the hydrogenation experimental platform. The hydrogenation chamber is also equipped with a hydrogen inlet and a hydrogen outlet. The high-pressure chamber is equipped with an upper pressure head and a lower pressure head that cooperate with each other.

[0006] The above-mentioned apparatus for preparing a metal-based hydride shielding material is characterized in that the alloy melting chamber, the hydrogenation chamber, and the high-pressure chamber are all connected to a vacuum assembly and an inert atmosphere protection assembly.

[0007] The above-mentioned apparatus for preparing a metal-based hydride shielding material is characterized in that the apparatus further comprises at least one robotic arm.

[0008] The apparatus for preparing a metal-based hydride shielding material, as described above, is characterized in that the tungsten crucible and the upper pressure head are of corresponding dimensions.

[0009] The above-mentioned apparatus for preparing a metal-based hydride shielding material is characterized in that the alloy melting chamber and the hydrogenation chamber, and the hydrogenation chamber and the high-pressure chamber are all connected by a connecting channel, and a gate valve is provided on each connecting channel.

[0010] In addition, the present invention also provides a method for preparing a metal-based hydride shielding material, characterized in that the method includes the following steps: Step 1: Place the base metal and neutron-absorbing element into the alloy melting chamber for melting, then cool to obtain an alloy block; Step 2: Place the alloy block obtained in Step 1 into a hydrogenation chamber for hydrogenation and crushing to obtain alloy hydride powder with high hydrogen content; Step 3: Place the alloy hydride powder obtained in Step 2 into a high-pressure chamber for cold pressing to obtain a bulk blank; Step 4: Place the bulk blank obtained in Step 3 into a hydrogenation chamber for multi-stage controlled-pressure hydrogenation sintering to obtain a metal-based hydride shielding material.

[0011] This invention achieves uniform mixing of the base metal and neutron-absorbing elements at the atomic scale through smelting, forming a homogeneous solid solution. This ensures the uniformity of the final material composition from the source. Hydrogenation crushing causes the alloy block to undergo a phase transformation and significant volume expansion during hydrogen absorption, leading to embrittlement and powdering. This yields high-hydrogen-content alloy hydride powder. It utilizes hydrogen-induced cracking, an effect generally considered harmful, transforming it into a highly efficient and energy-saving powder preparation method. Cold pressing forms a bulk blank with a certain porosity. These pores are crucial for the subsequent sintering process, serving two purposes: firstly, they can... The pores form a network of channels for hydrogen diffusion, promoting the uniform distribution of hydrogen within the billet. On the other hand, these pores also provide a buffer space for the volume expansion that may occur during subsequent heat treatment or hydrogenation sintering, effectively alleviating the resulting internal stress. Through multi-stage pressure-controlled hydrogenation sintering, and by controlling the gradient decrease in hydrogenation sintering temperature, hydrogen pressure, and time, excessive loss of hydrogen content is avoided, ensuring the homogenization of the high hydrogen concentration field and promoting the interaction between the metal matrix and the hydride phase. This results in a bulk material with uniform composition, dense structure, no cracks, and good shielding performance, effectively avoiding the cracking problems that are prone to occur in traditional bulk hydrogenation.

[0012] The above method is characterized in that, in step one, the base metal is selected from any one of Zr, Y, Ti, and Hf, and the neutron-absorbing element is selected from at least one of Gd, Sm, Dy, Er, Eu, Cd, and B; the total mass percentage of the neutron-absorbing element is 1% to 15%, with the balance being the base metal and unavoidable impurities; and the smelting is carried out under vacuum or inert atmosphere protection. This invention, by controlling the composition of the metal-based hydride shielding material, synergistically utilizes the excellent neutron moderation capability of the base metal hydride and the ultra-high absorption cross-section absorption characteristics of heavy rare earth and other neutron-absorbing metals, ensuring the material's excellent shielding performance.

[0013] The above method is characterized in that the hydrogenation crushing temperature in step two is 400℃~1000℃, the time is 2h~24h, and the hydrogen pressure is 0.1MPa~1MPa. This invention, by controlling the parameters of hydrogenation crushing, enables the alloy block to fully absorb hydrogen atoms and crush into alloy hydride powder with high hydrogen content.

[0014] The method described above is characterized in that the pressure for cold pressing in step three is 100 MPa to 300 MPa. By controlling the pressure during cold pressing, this invention can both cold press alloy hydride powder into shape, facilitating subsequent sintering and densification, and also allow for the creation of pores in the bulk blank, mitigating volume expansion during the subsequent multi-stage controlled-pressure hydrogenation sintering process and preventing crack formation.

[0015] The above method is characterized in that, in step four, the temperature of the first stage of the multi-stage pressure-controlled hydrogenation sintering is 1000℃~1400℃, the hydrogen pressure is 0.4MPa~0.6MPa, and the time is 3h~8h; the temperature of the second stage is 800℃~1100℃, the hydrogen pressure is 0.2MPa~0.4MPa, and the time is 2h~6h; and the temperature of the third stage is 700℃~900℃, the hydrogen pressure is 0.01MPa~0.2MPa, and the time is 1h~4h. This invention, through multi-stage pressure-controlled hydrogenation sintering and controlling the gradient decrease in hydrogenation sintering temperature, hydrogen pressure, and time, avoids excessive loss of hydrogen content, ensures the homogenization of the high hydrogen concentration field, and promotes the interaction between the metal matrix and the hydride phase, forming a bulk material with uniform composition, dense structure, no cracks, and good shielding performance. This effectively avoids the cracking problems that are easily generated in traditional bulk hydrogenation.

[0016] Compared with the prior art, the present invention has the following advantages: 1. This invention integrates multiple process steps into a metal-based hydride shielding material preparation device consisting of an alloy melting chamber, a hydrogenation chamber, and a high-pressure chamber that are sequentially interconnected. This achieves one-stop preparation from raw materials to the final product, simplifies the operation process, shortens the production cycle, and avoids the risk of contamination during material transfer, thus realizing integrated and efficient preparation.

[0017] 2. This invention uses alloy melting as the first step, which ensures the uniform distribution of the base metal and neutron-absorbing elements at the microscale, avoids the component segregation problem that may be caused by traditional powder mixing, and achieves high component uniformity, laying a solid foundation for the uniformity and reliability of material properties.

[0018] 3. This invention overturns the traditional approach of preparing bulk materials by first forming and then hydrogenating. It adopts a technical route of first melting → hydrogenating and crushing into powder → powder metallurgy forming. By utilizing the inherent porosity characteristics of powder metallurgy, it cleverly constructs hydrogen diffusion channels and volume expansion buffer space, avoiding hydrogen-induced cracking. This fundamentally solves the problem of cracking of large-sized bulk materials due to huge internal stress during hydrogenation.

[0019] 4. The powder obtained by hydrogenation crushing in this invention has high activity and high hydrogen content, which reduces the temperature and time of subsequent sintering. Through multi-stage pressure controlled hydrogenation sintering process, the densification and final hydrogenation process can be precisely controlled, realizing the homogenization of the hydrogen concentration field and microstructure of the material, ensuring the comprehensive performance and high yield of the material. The process has strong controllability and high yield.

[0020] 5. The material prepared by this invention integrates the excellent neutron moderation capability of the metal hydride matrix and the high-efficiency absorption characteristics of the neutron-absorbing element, achieving a perfect combination of neutron moderation and absorption. It is especially suitable for advanced nuclear energy systems with strict weight requirements, achieving synergistic performance.

[0021] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the apparatus for preparing the metal-based hydride shielding material of the present invention.

[0023] Figure 2 This is a physical image of the yttrium-based hydride shielding material prepared in Example 2 of the present invention.

[0024] Figure 3 The image shows the X-ray diffraction pattern of the yttrium-based hydride shielding material prepared in Example 2 of this invention.

[0025] Figure 4 The diagram shows the high-temperature hydrogen loss performance of the yttrium-based hydride shielding material prepared in Example 2 of this invention.

[0026] Figure 5 This is a physical image of the zirconium-based hydride shielding material prepared in Example 3 of the present invention.

[0027] Figure 6 The image shows the X-ray diffraction pattern of the zirconium-based hydride shielding material prepared in Example 3 of this invention.

[0028] Figure 7 The high-temperature hydrogen loss performance diagram is shown for the zirconium-based hydride shielding material prepared in Example 3 of this invention.

[0029] Explanation of reference numerals in the attached figures: Detailed Implementation

[0030] The apparatus for preparing a metal-based hydride shielding material according to the present invention is described in detail in Example 1.

[0031] Example 1 like Figure 1 As shown, the apparatus for preparing the metal-based hydride shielding material in this embodiment includes a sealed alloy melting chamber 1, a hydrogenation chamber 2, and a high-pressure chamber 3 that are connected in sequence. The alloy melting chamber 1 is equipped with an induction melting furnace 5 and a tungsten crucible 6. The hydrogenation chamber 2 is equipped with a hydrogenation experimental platform 11, on which a heating component is provided. The hydrogenation chamber 2 is also equipped with a hydrogen inlet 9 and a hydrogen outlet 10. The high-pressure chamber 3 is equipped with an upper pressure head 12 and a lower pressure head 13 that cooperate with each other.

[0032] It should be noted that the alloy melting chamber 1 is used to melt the raw materials. Specifically, an induction melting furnace 5 is used to melt the raw materials into alloy blocks. A tungsten crucible 6 is used to hold the base metal, neutron-absorbing elements, and the melt obtained after melting. It also serves as a mold for cold pressing to hold the alloy hydride powder. The hydrogenation chamber 2 is used to realize hydrogenation crushing and multi-stage controlled pressure hydrogenation sintering. Specifically, a hydrogenation experimental platform 11 is used to place the tungsten crucible 6. The tungsten crucible 6 is heated by a heating component to realize hydrogenation crushing and multi-stage controlled pressure hydrogenation sintering. The hydrogen atmosphere in the hydrogenation chamber 2 is maintained through the hydrogen inlet 9 and the hydrogen outlet 10, thus providing a hydrogen environment for hydrogenation crushing and multi-stage controlled pressure hydrogenation sintering. The high-pressure chamber 3 is used to realize cold pressing. Specifically, a lower pressure head 13 is used to place the tungsten crucible 6. The tungsten crucible 6 serves as a mold for cold pressing to hold the alloy hydride powder. It works in conjunction with the upper pressure head 12 and the lower pressure head 13 to realize cold pressing.

[0033] It should be noted that the induction melting furnace 5 uses an alumina crucible and is equipped with an electric tilting device to automatically pour the melt obtained by the induction melting furnace 5 into the tungsten crucible 6.

[0034] It should be noted that the hydrogenation chamber 2 is equipped with a digital pressure gauge for observing the pressure inside the hydrogenation chamber 2, the hydrogen inlet 9 is connected to a hydrogen source, and the heating component is a resistance heating component.

[0035] It should be noted that both the upper pressure head 12 and the lower pressure head 13 are made of stainless steel. The lower pressure head 13 is connected to a pressurizing component, which is a hydraulic press, to raise the lower pressure head 13 and cooperate with the upper pressure head 12 to achieve pressing.

[0036] In this embodiment, the alloy melting chamber 1, hydrogenation chamber 2, and high-pressure chamber 3 are all connected to the vacuum assembly and the inert atmosphere protection assembly. By setting up the vacuum assembly and the inert atmosphere protection assembly, a vacuum or inert atmosphere protection environment is provided for the device to achieve full-process environmental control.

[0037] It should be noted that both the vacuum assembly and the inert atmosphere protection assembly are connected to the hydrogenation chamber 2, which facilitates the control of the vacuum or inert atmosphere in the alloy melting chamber 1, the hydrogenation chamber 2, and the high-pressure chamber 3.

[0038] like Figure 1 As shown, in this embodiment, the device is also equipped with at least one robotic arm 4. By setting at least one robotic arm 4, the tungsten crucible 6 containing materials is accurately transferred between the alloy melting chamber 1, the hydrogenation chamber 2, and the high-pressure chamber 3; the robotic arm 4 can move up, down, forward, and backward, and is made of stainless steel.

[0039] It should be noted that a robotic arm 4 is installed in both the alloy melting chamber 1 and the high-pressure chamber 3. The robotic arm 4 in the alloy melting chamber 1 is used to transfer the tungsten crucible 6 from the alloy melting chamber 1 to the hydrogenation chamber 2, and the robotic arm 4 in the high-pressure chamber 3 is used to transfer the tungsten crucible 6 between the hydrogenation chamber 2 and the high-pressure chamber 3.

[0040] It should be noted that the tungsten crucible 6 is provided with a groove for the robotic arm 4 to insert into, which facilitates the robotic arm 4 to hold the tungsten crucible 6 and thus facilitates the transfer of the tungsten crucible 6.

[0041] In this embodiment, the tungsten crucible 6 and the upper pressure head 12 are of corresponding dimensions. By making the dimensions of the tungsten crucible 6 and the upper pressure head 12 correspond, even if the upper pressure head 12 is inserted into the tungsten crucible 6 to achieve cold pressing, there is no need to change the mold or break the vacuum for operation, which improves efficiency and reduces costs. Moreover, the dimensions of the tungsten crucible 6 and the upper pressure head 12 can be changed according to the product size requirements to achieve the preparation of products of different sizes.

[0042] like Figure 1 As shown, in this embodiment, the alloy melting chamber 1 and the hydrogenation chamber 2, as well as the hydrogenation chamber 2 and the high-pressure chamber 3, are all connected by a connecting channel 7, and each connecting channel 7 is equipped with a gate valve 8. The connecting channel 7 facilitates the transfer of the tungsten crucible 6 containing materials. The gate valves 8 are used to isolate or connect the alloy melting chamber 1, the hydrogenation chamber 2, and the high-pressure chamber 3, ensuring that each process can be carried out in an independent environment. Especially during hydrogenation crushing and multi-stage controlled-pressure hydrogenation sintering in the hydrogenation chamber 2, closing the two gate valves 8 creates an independent environment for the hydrogenation chamber 2, reducing hydrogen consumption and heat loss, thus lowering costs.

[0043] In this embodiment, the method of using the apparatus for preparing the metal-based hydride shielding material is as follows: Step 1: Place the base metal and neutron absorbing material as raw materials into the induction melting furnace 5 of the alloy melting chamber 1, open the gate valve 8 on the two connecting channels 7, turn on the vacuum assembly, remove the residual air in the alloy melting chamber 1, hydrogenation chamber 2 and high pressure chamber 3, maintain the vacuum state or fill with inert gas, then turn on the induction melting furnace 5 to melt the raw materials to obtain the alloy melt, and pour it into the tungsten crucible 6. After cooling, the tungsten crucible 6 containing the alloy block is obtained. Step 2: Transfer the tungsten crucible 6 containing the alloy block to the hydrogenation experimental platform 11 in the hydrogenation chamber 2 using the robotic arm 4, close the two gate valves 8 to keep the hydrogenation chamber 2 isolated from other chambers, introduce hydrogen gas into the hydrogenation chamber 2 to the predetermined pressure, turn on the heating device, and carry out hydrogenation crushing to obtain the tungsten crucible 6 containing hydride powder. Step 3: After hydrogenation and crushing are completed, the vacuum assembly is turned on to evacuate the hydrogenation chamber 2. Then, the gate valve 8 between the hydrogenation chamber 2 and the high-pressure chamber 3 is opened. The tungsten crucible 6 containing alloy hydride powder is transferred to the upper pressure head 12 and lower pressure head 13 of the high-pressure chamber 3 by the robotic arm 4. The pressurization assembly is turned on to cold press the alloy hydride powder to obtain the tungsten crucible 6 containing the block blank. Step 4: Using robotic arm 4, the tungsten crucible 6 containing the bulk blank is transferred back to the hydrogenation experimental platform 11 of the hydrogenation chamber 2. The gate valve 8 between the hydrogenation chamber 2 and the high-pressure chamber 3 is closed. Hydrogen gas is introduced into the hydrogenation chamber 2 and the heating device is turned on to carry out multi-stage controlled pressure hydrogenation sintering. After sintering, the furnace is cooled to room temperature to obtain a metal-based hydride shielding material in the tungsten crucible 6.

[0044] The preparation method of a metal-based hydride shielding material of the present invention is described in detail through Examples 2 to 6.

[0045] Example 2 This embodiment includes the following steps: Step 1: Place the base metal Y and neutron-absorbing elements Dy, Sm and B into the alloy melting chamber and melt them under vacuum, then cool to obtain an alloy block; Step 2: Place the alloy block obtained in Step 1 into a hydrogenation chamber for hydrogenation crushing. The hydrogenation crushing temperature is 600℃, the time is 10h, and the hydrogen pressure is 0.8MPa to obtain alloy hydride powder with high hydrogen content. Step 3: Place the alloy hydride powder obtained in Step 2 into a high-pressure chamber for cold pressing. The cold pressing pressure is 200 MPa to obtain a block blank. Step 4: Place the bulk blank obtained in Step 3 into a hydrogenation chamber for multi-stage controlled-pressure hydrogenation sintering. In the multi-stage controlled-pressure hydrogenation sintering, the temperature of the first stage is 1300℃, the hydrogen pressure is 0.5MPa, and the time is 5h; the temperature of the second stage is 1000℃, the hydrogen pressure is 0.3MPa, and the time is 3h; and the temperature of the third stage is 800℃, the hydrogen pressure is 0.1MPa, and the time is 2h, to obtain the yttrium-based hydride shielding material.

[0046] Testing revealed that the yttrium-based hydride shielding material prepared in this embodiment contained 3% Dy, 4% Sm, and 2% B by mass, with the remainder being Y and unavoidable impurities. Furthermore, the yttrium-based hydride shielding material exhibited uniform composition, dense structure, and no cracks.

[0047] Figure 2 Here is a physical image of the yttrium-based hydride shielding material prepared in this embodiment. Figure 2 As can be seen from the image, the yttrium-based hydride shielding material prepared in this embodiment has a smooth surface without cracks.

[0048] Figure 3 This is the X-ray diffraction pattern of the yttrium-based hydride shielding material prepared in this embodiment. Figure 3 The yttrium alloy hydride in the text refers to the yttrium-based hydride shielding material obtained in step four, and the yttrium alloy refers to the alloy bulk material obtained in step one. Figure 3 As can be seen, the main phase of the alloy block obtained in step one is α-Y, and the phase of the yttrium-based hydride shielding material obtained in step four is δ-YH2. This embodiment successfully prepared a yttrium-based hydride shielding material with high hydrogen content.

[0049] Figure 4 This is a high-temperature hydrogen loss performance diagram of the yttrium-based hydride shielding material prepared in this embodiment. Figure 4 As can be seen from the data, the yttrium-based hydride shielding material prepared in this embodiment only exhibits significant hydrogen loss after 700°C, indicating that yttrium-based hydrides have excellent high-temperature resistance.

[0050] Example 3 This embodiment includes the following steps: Step 1: Place the base metal Zr and neutron-absorbing elements Gd and Sm into the alloy melting chamber and melt them under the protection of an inert gas. Then cool the mixture to obtain an alloy block. Step 2: Place the alloy block obtained in Step 1 into a hydrogenation chamber for hydrogenation crushing. The hydrogenation crushing temperature is 1000℃, the time is 2h, and the hydrogen pressure is 0.1MPa to obtain alloy hydride powder with high hydrogen content. Step 3: Place the alloy hydride powder obtained in Step 2 into a high-pressure chamber for cold pressing. The cold pressing pressure is 100 MPa to obtain a block blank. Step 4: Place the bulk blank obtained in Step 3 into a hydrogenation chamber for multi-stage controlled-pressure hydrogenation sintering. In the multi-stage controlled-pressure hydrogenation sintering, the temperature of the first stage is 1000℃, the hydrogen pressure is 0.6MPa, and the time is 8h; the temperature of the second stage is 800℃, the hydrogen pressure is 0.4MPa, and the time is 6h; and the temperature of the third stage is 700℃, the hydrogen pressure is 0.2MPa, and the time is 4h, to obtain the zirconium-based hydride shielding material.

[0051] Testing revealed that the zirconium-based hydride shielding material prepared in this embodiment contained 5% Gd by mass and 10% Zr by mass, with the remainder being Zr and unavoidable impurities. Furthermore, the zirconium-based hydride shielding material exhibited uniform composition, dense structure, and no cracks.

[0052] Figure 5 Here is a physical image of the zirconium-based hydride shielding material prepared in this embodiment. Figure 5 As can be seen from the example, this embodiment produces a zirconium-based hydride shielding material with a smooth surface and no crack defects.

[0053] Figure 6 This is the X-ray diffraction pattern of the zirconium-based hydride shielding material prepared in this embodiment. Figure 6 The zirconium alloy hydride in this context refers to the zirconium-based hydride shielding material obtained in step four, and the zirconium alloy is the alloy bulk material obtained in step one. Figure 6 As can be seen from the figure, the main phase of the alloy block obtained in step one is α-Zr, and the phase of the zirconium-based hydride shielding material obtained in step four is ε-ZH2. This embodiment successfully prepared a zirconium-based hydride shielding material with high hydrogen content.

[0054] Figure 7 This is a high-temperature hydrogen loss performance diagram of the zirconium-based hydride shielding material prepared in this embodiment. Figure 7 As can be seen from the data, the zirconium-based hydride shielding material prepared in this embodiment begins to exhibit dehydrogenation after 400°C.

[0055] Example 4 This embodiment includes the following steps: Step 1: Place the base metal Ti and neutron-absorbing elements Eu and Er into an alloy melting chamber and melt them under vacuum, then cool to obtain an alloy block. Step 2: Place the alloy block obtained in Step 1 into a hydrogenation chamber for hydrogenation crushing. The hydrogenation crushing temperature is 400℃, the time is 24h, and the hydrogen pressure is 1MPa to obtain alloy hydride powder with high hydrogen content. Step 3: Place the alloy hydride powder obtained in Step 2 into a high-pressure chamber for cold pressing. The cold pressing pressure is 300 MPa to obtain a block blank. Step 4: Place the bulk blank obtained in Step 3 into a hydrogenation chamber for multi-stage controlled-pressure hydrogenation sintering. The temperature of the first stage of the multi-stage controlled-pressure hydrogenation sintering is 1100℃, the hydrogen pressure is 0.55MPa, and the time is 6h. The temperature of the second stage is 900℃, the hydrogen pressure is 0.35MPa, and the time is 4h. The temperature of the third stage is 750℃, the hydrogen pressure is 0.15MPa, and the time is 3h, to obtain the titanium-based hydride shielding material.

[0056] Testing revealed that the titanium-based hydride shielding material prepared in this embodiment contained 0.5% Eu and 0.5% Er by mass, with the remainder being Ti and unavoidable impurities. Furthermore, the titanium-based hydride shielding material exhibited uniform composition, dense structure, and no cracks.

[0057] Example 5 This embodiment includes the following steps: Step 1: Place the base metal Hf and neutron-absorbing elements Er and Dy into an alloy melting chamber and melt them under inert gas protection. Then cool the mixture to obtain an alloy block. Step 2: Place the alloy block obtained in Step 1 into a hydrogenation chamber for hydrogenation crushing. The hydrogenation crushing temperature is 800℃, the time is 6h, and the hydrogen pressure is 0.6MPa to obtain alloy hydride powder with high hydrogen content. Step 3: Place the alloy hydride powder obtained in Step 2 into a high-pressure chamber for cold pressing. The cold pressing pressure is 150 MPa to obtain a block blank. Step 4: Place the bulk billet obtained in Step 3 into a hydrogenation chamber for multi-stage controlled-pressure hydrogenation sintering. In the multi-stage controlled-pressure hydrogenation sintering, the temperature of the first stage is 1400℃, the hydrogen pressure is 0.4MPa, and the time is 3h; the temperature of the second stage is 1100℃, the hydrogen pressure is 0.2MPa, and the time is 2h; and the temperature of the third stage is 800℃, the hydrogen pressure is 0.01MPa, and the time is 1h, to obtain hafnium-based hydride shielding material.

[0058] Testing revealed that the hafnium-based hydride shielding material prepared in this embodiment contained 6% Dy by mass, 4% Er by mass, with the remainder being Hf and unavoidable impurities. Furthermore, the hafnium-based hydride shielding material exhibited uniform composition, dense structure, and no cracks.

[0059] Example 6 This embodiment includes the following steps: Step 1: Place the base metal Y and neutron-absorbing elements Eu and B into the alloy melting chamber and melt them under vacuum, then cool to obtain an alloy block; Step 2: Place the alloy block obtained in Step 1 into a hydrogenation chamber for hydrogenation crushing. The hydrogenation crushing temperature is 700℃, the time is 12h, and the hydrogen pressure is 0.8MPa to obtain alloy hydride powder with high hydrogen content. Step 3: Place the alloy hydride powder obtained in Step 2 into a high-pressure chamber for cold pressing. The cold pressing pressure is 250 MPa to obtain a block blank. Step 4: Place the bulk blank obtained in Step 3 into a hydrogenation chamber for multi-stage controlled-pressure hydrogenation sintering. In the multi-stage controlled-pressure hydrogenation sintering, the temperature of the first stage is 1250℃, the hydrogen pressure is 0.45MPa, and the time is 5h; the temperature of the second stage is 1000℃, the hydrogen pressure is 0.2MPa, and the time is 3h; and the temperature of the third stage is 850℃, the hydrogen pressure is 0.1MPa, and the time is 1h, to obtain yttrium-based hydride shielding material.

[0060] Testing revealed that the yttrium-based hydride shielding material prepared in this embodiment contained 3% Eu by mass, 1% B by mass, and the remainder was Y and unavoidable impurities. Furthermore, the yttrium-based hydride shielding material exhibited uniform composition, dense structure, and no cracks.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. An apparatus for preparing a metal-based hydride shielding material, characterized in that, The device includes a sealed alloy melting chamber (1), a hydrogenation chamber (2) and a high-pressure chamber (3) that are connected in sequence. The alloy melting chamber (1) is equipped with an induction melting furnace (5) and a tungsten crucible (6). The hydrogenation chamber (2) is equipped with a hydrogenation test bench (11) and a heating component. The hydrogenation chamber (2) is also equipped with a hydrogen inlet (9) and a hydrogen outlet (10). The high-pressure chamber (3) is equipped with an upper pressure head (12) and a lower pressure head (13) that cooperate with each other.

2. The apparatus for preparing a metal-based hydride shielding material according to claim 1, characterized in that, The alloy melting chamber (1), hydrogenation chamber (2) and high-pressure chamber (3) are all connected to the vacuum assembly and the inert atmosphere protection assembly.

3. The apparatus for preparing a metal-based hydride shielding material according to claim 1, characterized in that, The device also includes at least one robotic arm (4).

4. The apparatus for preparing a metal-based hydride shielding material according to claim 1, characterized in that, The tungsten crucible (6) and the upper pressure head (12) are of corresponding dimensions.

5. The apparatus for preparing a metal-based hydride shielding material according to claim 1, characterized in that, The alloy melting chamber (1) and the hydrogenation chamber (2), and the high-pressure chamber (3) are all connected by a connecting channel (7), and a gate valve (8) is provided on the connecting channel (7).

6. A method for preparing a metal-based hydride shielding material using the apparatus according to any one of claims 1 to 5, characterized in that, The method includes the following steps: Step 1: Place the base metal and neutron-absorbing element into the alloy melting chamber (1) for melting, and then cool to obtain an alloy block; Step 2: Place the alloy block obtained in Step 1 into the hydrogenation chamber (2) for hydrogenation and crushing to obtain alloy hydride powder with high hydrogen content; Step 3: Place the alloy hydride powder obtained in step 2 into a high-pressure chamber (3) for cold pressing to obtain a block blank; Step 4: Place the bulk blank obtained in Step 3 into the hydrogenation chamber (2) for multi-stage controlled pressure hydrogenation sintering to obtain a metal-based hydride shielding material.

7. The method according to claim 6, characterized in that, The base metal in step one is selected from any one of Zr, Y, Ti and Hf, and the neutron absorbing element is selected from at least one of Gd, Sm, Dy, Er, Eu, Cd and B; the total mass percentage of the neutron absorbing element is 1% to 15%, with the balance being the base metal and unavoidable impurities; the smelting is carried out under vacuum or inert atmosphere protection.

8. The method according to claim 6, characterized in that, The hydrogenation crushing temperature in step two is 400℃~1000℃, the time is 2h~24h, and the hydrogen pressure is 0.1MPa~1MPa.

9. The method according to claim 6, characterized in that, The pressure for cold pressing in step three is 100MPa~300MPa.

10. The method according to claim 6, characterized in that, In step four, the temperature of the first stage of the multi-stage pressure controlled hydrogenation sintering is 1000℃~1400℃, the hydrogen pressure is 0.4MPa~0.6MPa, and the time is 3h~8h; the temperature of the second stage is 800℃~1100℃, the hydrogen pressure is 0.2MPa~0.4MPa, and the time is 2h~6h; and the temperature of the third stage is 700℃~900℃, the hydrogen pressure is 0.01MPa~0.2MPa, and the time is 1h~4h.

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