Component for rocket engine, component for artificial celestial body, and component for survey vehicle

Abstract

The present invention addresses the problem of providing a component for a rocket engine that achieves both light weight and high durability, and ensures complete combustion of structural materials of a spacecraft during atmospheric reentry, thereby preventing unburned residues from a spacecraft, which has reached the end of the operational life, from falling onto the earth. The component is also capable of realizing cost reduction and high precision even in large-scale designs.　A component for a rocket engine according to the present invention is formed by additive manufacturing using a metal 3D printer, and includes beryllium and / or a beryllium alloy, a high-entropy alloy having three or more types of elements, and one or more selected from a composite material including a ceramic and aluminum. In the high-entropy alloy, the atomic ratio of each of the three or more types of elements is 50% or less.

Description

Rocket engine parts, artificial celestial body parts and exploration vehicle parts

[0001] The present invention relates to rocket engine parts, artificial celestial body parts, and exploration vehicle parts.

[0002] Equipment used in space, such as artificial satellites, is carried from the ground to space on a rocket, so there is a demand for lightweight, high-performance equipment to be transported by rocket.

[0003] Therefore, the applicant has proposed a fuel cell that can be used in outer space, as described in Patent Document 1. This fuel cell is lightweight and has excellent durability, as the separator and / or housing are configured to contain beryllium and / or a beryllium alloy.

[0004] Patent No. 7126728

[0005] In addition to the performance required of fuel cells, components for artificial satellites and rockets are also required to enable the rocket to burn up or break into small pieces when it enters the atmosphere.

[0006] Artificial satellites that have reached the end of their design life and ceased to function or become uncontrollable due to an accident, or spacecraft that do not need to be recovered, such as the upper stages of rockets launched into space, will eventually enter the atmosphere and burn up due to the heat of friction with the air during the re-entry process.

[0007] However, although rare, there are cases where a spacecraft does not burn up completely upon re-entry into the atmosphere, and parts of the craft fall to Earth, and there have actually been confirmed cases where components of large spacecraft have fallen to Earth.

[0008] In addition, rocket structures and parts must be low-cost, and rocket engines in particular are the main components of rockets and must be large and precise.

[0009] The present invention has been made in light of the above circumstances, and its purpose is to provide rocket engine parts, artificial celestial body parts, and exploration vehicle parts that are both lightweight and highly durable, and that prevent the remains of a spacecraft that has completed its lifespan from falling to Earth by ensuring that the materials that make up the spacecraft are burned up when the spacecraft re-enters the atmosphere, and that are low-cost and can be made precise even when large.

[0010] As a result of extensive research into solving the above problems, the inventors discovered that the above object can be achieved by configuring at least a portion of rocket engine components to contain beryllium and / or a beryllium alloy, and thus completed the present invention. Specifically, the present invention provides the following.

[0011] A first aspect of the invention provides a rocket engine component additively manufactured using a metal 3D printer, the rocket engine component including beryllium and / or a beryllium alloy, and further including one or more of: a high-entropy alloy having three or more elements; and a composite material having ceramic and aluminum, wherein the high-entropy alloy is an alloy in which the atomic ratio of each of the three or more elements is 50% or less.

[0012] According to the first aspect of the invention, it is possible to provide a rocket engine component that is lightweight, has excellent durability, is low-cost, and can be made precise even when large. Furthermore, by ensuring that the materials that make up the spacecraft burn out when it re-enters the atmosphere, it is possible to prevent the remains of the spacecraft that has completed its lifespan from falling to Earth, and it is also possible to provide a rocket engine component that is low-cost, and can be made precise even when large.

[0013] Rocket engine parts are required to be lightweight due to payload limitations on rockets that launch them from the ground. For this reason, rocket engine parts used in space must be highly durable. Moreover, rocket engine parts must be large yet precise.

[0014] Therefore, rocket engine parts must be both lightweight and durable, and also large in size yet precise.

[0015] Beryllium has a specific gravity of 1.85 g / cm at a temperature of 25°C and a pressure of 1013 hPa. ３ and copper (specific gravity under the same conditions: 8.96 g / cm ３ Beryllium is a very light element compared to other metals. That is, a housing and / or separator containing beryllium can be constructed to be lightweight. Similar properties can be expected for a housing and / or separator containing a beryllium alloy.

[0016] Beryllium has a Young's modulus of 287 GPa, which is higher than that of copper (Young's modulus: 100 to 128 GPa). Therefore, beryllium has high bending strength. In other words, a housing and / or separator containing beryllium has excellent durability that can prevent breakage due to bending. Similar properties can be expected for a housing and / or separator containing a beryllium alloy.

[0017] Beryllium has a modulus of rigidity of 132 GPa, which is higher than that of copper (modulus of rigidity 48 GPa). Therefore, beryllium is less likely to deform due to external forces, etc. In other words, a housing and / or separator containing beryllium has excellent durability that can prevent loss of function due to deformation due to external forces, etc. Similar properties can be expected from a housing and / or separator containing a beryllium alloy.

[0018] The Vickers hardness of beryllium is 1670 MPa, which is higher than the Vickers hardness of copper (369 MPa). Therefore, beryllium is harder than copper. Furthermore, a housing and / or separator containing beryllium is less susceptible to scratches than a copper housing and / or separator and has excellent durability. Similar properties can be expected for a housing and / or separator containing a beryllium alloy.

[0019] The melting point of beryllium is 1560 K, which is higher than the melting point of copper (1357.77 K). Therefore, a housing and / or separator containing beryllium has better durability and higher temperature resistance than a housing and / or separator made of copper. Similar properties can be expected for a housing and / or separator containing a beryllium alloy.

[0020] The thermal expansion coefficient of beryllium is 11.3 x 10 at 25°C. －６ [1 / K], and copper (16.5 × 10 －６ The thermal expansion coefficient of beryllium is lower than that of copper (1 / K). Therefore, a housing and / or separator containing beryllium is less susceptible to deformation due to temperature changes than a copper housing and / or separator, and has excellent durability. Similar properties can be expected from beryllium alloys.

[0021] According to the first aspect of the invention, it is possible to construct rocket engine components that are lightweight and have excellent durability.

[0022] Therefore, according to the first aspect of the invention, it is possible to provide a rocket engine component that is both lightweight and highly durable.

[0023] Furthermore, by using a metal 3D printer, it is possible to form an additively molded object without welding, thereby avoiding the problem of welded parts having lower strength than other parts. Therefore, additively molded objects formed by a metal 3D printer can be larger yet more precise, and can also achieve superior durability compared to molded objects formed by welding.

[0024] A second aspect of the invention is the first aspect of the invention, wherein the high-entropy alloy is a high-entropy alloy containing five or more elements.

[0025] According to a second aspect of the present invention, a high-entropy alloy is known, which is an alloy containing five or more elements, each of which has an atomic ratio of 50% or less. High-entropy alloys are known to have excellent heat resistance, high-temperature strength, corrosion resistance, and the like. In other words, high-entropy alloys are alloys with excellent durability. Therefore, it is possible to provide rocket engine components that are both lightweight and durable.

[0026] A third aspect of the invention provides a rocket engine component according to the first or second aspect of the invention, wherein the beryllium alloy contains 90% or more beryllium in atomic ratio.

[0027] According to the third aspect of the present invention, since the beryllium alloy contains 90% or more beryllium by atomic ratio, the beryllium alloy can be made lighter than beryllium, and therefore the housing and / or separator containing the beryllium alloy can be made even lighter.

[0028] Furthermore, according to the third feature of the present invention, the beryllium alloy contains 90% or more beryllium in atomic ratio, so that the beryllium alloy can be an alloy with superior durability similar to that of beryllium.

[0029] Therefore, according to the third aspect of the invention, it is possible to provide a rocket engine component that is both lightweight and highly durable.

[0030] A fourth aspect of the invention is the first or second aspect of the invention, wherein the beryllium alloy contains an element whose specific gravity as a simple substance at a temperature of 25°C and a pressure of 1013 hPa is approximately the same as or less than that of titanium.

[0031] According to the fourth aspect of the invention, the beryllium alloy contains an element whose specific gravity as a single element at a temperature of 25°C and a pressure of 1013 hPa is approximately the same as or less than that of titanium, making it possible to make the beryllium alloy an even lighter alloy.

[0032] Therefore, according to the fourth aspect of the invention, it is possible to provide a rocket engine component that is both lightweight and highly durable.

[0033] The invention according to a fifth feature provides a rocket engine component according to any one of the first to fourth features, wherein the separator and / or the housing is an additively manufactured body produced by a metal 3D printer.

[0034] When forming large components, a technique for forming a complex-shaped object by welding multiple components having relatively simple shapes is known. The welding-and-forming technique can form complex-shaped objects, such as those with protrusions, internal recesses and / or holes, etc. However, the welding-and-forming technique can result in weaker welded areas than other areas. Therefore, the welding-and-forming technique leaves room for further improvement in durability.

[0035] Metal 3D printers are known that form metal additively molded objects using techniques such as sintering and laminating metal powder with a laser and / or electron beam, cutting and laminating sheet metal, and sintering and laminating metal wire with a laser and / or electron beam. Using a metal 3D printer allows for the formation of metal additively molded objects without welding, thereby preventing the strength of welded areas from being lower than that of other areas. Therefore, metal additively molded objects formed by a metal 3D printer can achieve superior durability compared to objects formed by welding.

[0036] Therefore, according to the fifth aspect of the invention, it is possible to provide a rocket engine component that is both lightweight and highly durable.

[0037] The invention according to a sixth feature is an invention according to any one of the first to fifth features, wherein the rocket engine part includes a tank for storing liquid hydrogen therein, the tank having a cylindrical cylinder portion and dome portions that close both ends of the cylinder portion, and the rocket engine part is provided in which the cylinder portion and the dome portion are integrally additively manufactured using a metal 3D printer.

[0038] According to the sixth aspect of the present invention, the cylinder and dome sections are integrally additively manufactured using a metal 3D printer, so there is no seam between them. Therefore, a liquid hydrogen tank manufactured using a metal 3D printer can achieve greater durability than a tank manufactured by welding.

[0039] The invention according to a seventh aspect provides an artificial celestial body part that is additively manufactured using a metal 3D printer and that constitutes at least a part of the artificial celestial body to be loaded onto a rocket and placed in outer space, the artificial celestial body part comprising: beryllium and / or a beryllium alloy; and one or more selected from a high-entropy alloy having three or more elements, and a composite material having ceramic and aluminum, wherein the high-entropy alloy is an alloy in which the atomic ratio of each of the three or more elements is 50% or less.

[0040] According to the seventh aspect of the invention, similar to the first aspect of the invention, it is possible to provide an artificial celestial body component that is both lightweight and highly durable, thereby enabling the weight of the rocket carrying the artificial celestial body to be reduced.

[0041] The eighth aspect of the invention is the seventh aspect of the invention, wherein the high-entropy alloy is a high-entropy alloy containing five or more elements.

[0042] According to the eighth aspect of the invention, a high-entropy alloy similar to that used in the second aspect of the invention is used, making it possible to provide artificial celestial body components that are both lightweight and highly durable.

[0043] A ninth aspect of the invention provides a component for an artificial celestial body according to the seventh or eighth aspect of the invention, wherein the beryllium alloy contains 90% or more beryllium in atomic ratio.

[0044] According to the ninth aspect of the invention, the same beryllium alloy as that of the third aspect is used, thereby providing an artificial celestial body component that is both lightweight and highly durable.

[0045] The invention according to a tenth feature is an invention according to any one of the seventh to ninth features, wherein the beryllium alloy provides a component for an artificial celestial body containing an element whose specific gravity as a simple substance at a temperature of 25°C and a pressure of 1013 hPa is approximately the same as or less than that of titanium.

[0046] According to the tenth feature of the invention, the same beryllium alloy as in the fourth feature of the invention is used, thereby providing an artificial celestial body component that is both lightweight and highly durable.

[0047] The invention according to the eleventh feature is an invention according to any one of the seventh to tenth features, and provides a component for an artificial celestial body that constitutes an engine that generates thrust for controlling the orbit and attitude of the artificial celestial body.

[0048] According to the eleventh aspect of the present invention, it is possible to provide an engine for an artificial celestial body that is both lightweight and highly durable, thereby enabling the weight of the rocket carrying the artificial celestial body to be reduced.

[0049] The invention according to a twelfth feature is the invention according to any one of the seventh to eleventh features, wherein the artificial celestial body is an artificial satellite orbiting the Earth.

[0050] According to the twelfth aspect of the present invention, it is possible to provide an artificial satellite that is both lightweight and highly durable, thereby enabling the weight of the rocket carrying the artificial satellite to be reduced.

[0051] The invention according to a thirteenth feature is the invention according to any one of the seventh to eleventh features, wherein the artificial celestial body is a probe moving toward a predetermined celestial body other than the Earth.

[0052] According to the thirteenth feature of the present invention, it is possible to provide a probe that is both lightweight and highly durable, thereby enabling the weight of the rocket carrying the probe to be reduced.

[0053] The invention according to a fourteenth feature provides a probe vehicle part that is additively manufactured using a metal 3D printer and is mounted on a probe traveling through space toward a specified celestial body other than the Earth, and that constitutes at least a part of the probe vehicle that travels on the ground of the specified celestial body, the probe vehicle part comprising beryllium and / or a beryllium alloy, and one or more selected from a high-entropy alloy having three or more elements, and a composite material having ceramic and aluminum, wherein the high-entropy alloy is an alloy in which the atomic ratio of each of the three or more elements is 50% or less.

[0054] According to the fourteenth feature of the invention, similar to the first feature of the invention, it is possible to provide a light-weight and durable exploration vehicle component, thereby reducing the weight of the rocket carrying the exploration vehicle.

[0055] According to the present invention, it is possible to provide rocket engine parts, artificial celestial body parts, and exploration vehicle parts that are both lightweight and highly durable.

[0056] FIG. 1 is a side view showing the general structure of a rocket 100 equipped with rocket engine components according to this embodiment. FIG. 2 is a schematic diagram showing a fuel cell 1 according to this embodiment as viewed from the front. FIG. 3 is an enlarged schematic diagram showing the periphery of a cell 4 of the fuel cell 1 shown in FIG. 2. FIG. 4 is an enlarged schematic diagram showing the periphery of a cell 4 of a flat-plate solid oxide fuel cell. FIG. 5 is an enlarged schematic diagram showing the periphery of a cell 4 of a cylindrical solid oxide fuel cell. FIG. 6 is an enlarged schematic diagram showing the periphery of a cell 4 of an alkaline electrolyte fuel cell. FIG. 7 is an enlarged schematic diagram showing the periphery of a cell 4 of a molten carbonate fuel cell. FIG. 8 is an enlarged schematic diagram showing the periphery of a cell 4 of a phosphoric acid fuel cell. FIG. 9 is a schematic diagram showing the fuel cell 1 according to this embodiment as viewed obliquely from above. FIG. 10 is a schematic piping diagram of a first rocket engine 111. FIG. 11 is a diagram showing some components constituting the first rocket engine 111. FIG. 12 is a diagram showing some components that make up the first rocket engine 111. FIG. 13 is a diagram showing some components that make up the first rocket engine 111. FIG. 14 is a diagram showing some components that make up the first rocket engine 111. FIG. 15 is a diagram showing some components that make up the first rocket engine 111. FIG. 16 is a diagram showing some components that make up the first rocket engine 111. FIG. 17 is a diagram showing some components that make up the first rocket engine 111. FIG. 18 is a diagram showing some components that make up the first rocket engine 111. FIG. 19 is a diagram showing some components that make up the first rocket engine 111. FIG. 20 is a diagram showing some components that make up the first rocket engine 111. FIG. 21 is a diagram showing some components that make up the first rocket engine 111. FIG. 22 is a diagram showing some components that make up the first rocket engine 111. FIG. 23 is a perspective view that schematically shows the general configuration of the first liquid hydrogen tank 112. FIG. 24A is a diagram showing a supply vehicle that stores supplies to be supplied to the space station. FIG. 24B is a diagram showing the arrangement of attitude control thrusters in a capsule that is mounted on the supply vehicle shown in FIG. 24A and stores supplies from the space station.FIG. 25 is a schematic diagram showing the configuration of the second-stage liquid-fuel rocket 120. FIG. 26 is a diagram showing experimental results of the density and tensile strength of the material system of Example 1 and the comparative material. FIG. 27 is a diagram showing experimental results of the density and tensile strength of the material system of Example 1 and the comparative material. FIG. 28 is a diagram showing experimental results of the density and tensile strength of the material system of Example 1 and the comparative material. FIG. 29 is a diagram showing experimental results of the density and tensile strength of the material system of Example 2 and the comparative material. FIG. 30 is a diagram showing experimental results of the density and tensile strength of the material system of Example 3 and the comparative material. FIG. 31 is a diagram showing experimental results of the density and tensile strength of the material system of Example 4 and the comparative material. FIG. 32 is a diagram showing experimental results of the density and tensile strength of the material system of Example 4 and the comparative material. FIG. 33 is a diagram showing experimental results of the density and tensile strength of the material system of Example 4 and the comparative material. FIG. 34 is a diagram showing experimental results of the density and tensile strength of the material system of Example 4 and the comparative material. Fig. 35 is a diagram showing the experimental results of the density and tensile strength of the material system of Example 5 and the comparative material. Fig. 36 is a conceptual diagram showing an example of a manufacturing process for a rocket part made of an alloy structure.

[0057] An example of a preferred embodiment of the present invention will be described below with reference to the drawings. Note that this is merely an example, and the technical scope of the present invention is not limited to this example.

[0058] <Rocket 100> FIG. 1 is a side view showing the schematic structure of a rocket 100 equipped with rocket engine components according to this embodiment.

[0059] The rocket 100 is composed of four main parts: a first stage liquid fuel rocket 110 , a second stage liquid fuel rocket 120 , a satellite fairing 130 , and a solid fuel rocket 140 .

[0060] First-stage liquid-fuel rocket 110 has first rocket engine 111, first liquid hydrogen tank 112 for storing liquid hydrogen, and first liquid oxygen tank 113 for storing liquid oxygen. First-stage liquid-fuel rocket 110 is the largest part of rocket 100, and is responsible for the ascent and acceleration of the entire rocket 100 from the initial stage of launch.

[0061] The second-stage liquid fuel rocket 120 has a second rocket engine 121, a second liquid oxygen tank 122 for storing liquid oxygen, and a second liquid hydrogen tank 123 for storing liquid hydrogen. The second-stage liquid fuel rocket 120 is configured to perform final combustion of the satellite or the like after the first stage combustion by the first rocket engine 111 is completed, by separating the first rocket engine 111, the first liquid hydrogen tank 112, and the first liquid oxygen tank 113, and then performing combustion to achieve final acceleration and place the satellite or the like into a precise orbit.

[0062] The satellite fairing 130 is a cover that protects the satellite from air resistance, aerodynamic heating, external acoustics, etc. during launch.

[0063] The first liquid hydrogen tank 112, the first liquid oxygen tank 113, the second liquid oxygen tank 122, and the second liquid hydrogen tank 123 have their inner surfaces machined into a lattice pattern (isogrid structure) in order to minimize their mass while maintaining their strength.

[0064] The first stage liquid fuel rocket 110 is equipped with an engine, a tank, various on-board electronic devices, a helium pressurized tank, and the like.

[0065] The second stage liquid fuel rocket 120 includes an engine, a tank, an inertial guidance system, electronic equipment, and the like.

[0066] The rocket 100 also carries multiple fuel cells 1 that serve as power sources for various electronic devices mounted on the rocket 100 and various devices housed within the satellite fairing 130.

[0067] 2 is a schematic diagram showing the overall front view of the fuel cell 1 of this embodiment. The fuel cell 1 includes at least a housing 2, one or more separators 3 (e.g., the first separator 3a to the seventh separator 3g in FIG. 2), and two or more cells 4 (e.g., the first cell 4a to the sixth cell 4f in FIG. 2).

[0068] [Housing 2] The housing 2 houses the separators 3 and the cells 4 in a predetermined positional relationship. There are no particular limitations on the housing 2, and it may be a housing for a conventional fuel cell. By providing the housing 2, the separators 3 and the cells 4 can be housed in a predetermined positional relationship that allows the fuel cell to operate optimally.

[0069] The housing 2 preferably contains beryllium and / or a beryllium alloy. Fuel cells used in outer space are required to be lightweight due to payload limitations imposed by rockets and other vehicles that launch fuel cells from Earth. Space can be subject to extreme temperature conditions, both high and low. Furthermore, repairs and other procedures are more difficult for fuel cells used in space than for devices used on Earth. For these reasons, fuel cells used in space are required to have excellent durability.

[0070] Beryllium has a specific gravity of 1.85 g / cm at a temperature of 25°C and a pressure of 1013 hPa. ３ and copper (specific gravity under the same conditions: 8.96 g / cm ３ Beryllium is an extremely light element compared to other elements. That is, the housing 2 containing beryllium can be constructed to be lightweight. Similar characteristics can be expected for the housing 2 containing a beryllium alloy.

[0071] Beryllium has a Young's modulus of 287 GPa, which is higher than that of copper (100 to 128 GPa). Therefore, beryllium has high bending strength. In other words, a housing 2 containing beryllium has excellent durability that can prevent breakage due to bending. Similar characteristics can be expected for a housing 2 containing a beryllium alloy.

[0072] The modulus of rigidity of beryllium is 132 GPa, which is higher than that of copper (48 GPa). Therefore, beryllium is less likely to deform due to external forces, etc. In other words, a housing 2 containing beryllium has excellent durability that can prevent loss of functionality due to deformation due to external forces, etc. Similar characteristics can be expected for a housing 2 containing a beryllium alloy.

[0073] Fuel cells used in outer space may be subjected to large accelerations, such as 4 G in the vertical direction and 2 G in the horizontal direction, when launched by a rocket or the like. The accelerations during launch can cause the housing to deform and impair its functionality. The housing 2 containing beryllium and / or a beryllium alloy has a high modulus of rigidity, and thus can prevent deformation and impairment of functionality due to the acceleration. Therefore, by including beryllium and / or a beryllium alloy in the housing 2, a fuel cell 1 that can be used in outer space can be provided.

[0074] Since outer space is essentially a vacuum, a fuel cell used in outer space may be subjected to a force caused by a pressure difference between the gas containing fuel and / or oxygen inside the housing and the vacuum outside the housing. The housing 2 containing beryllium and / or a beryllium alloy has a high rigidity, and therefore can prevent deformation due to this pressure difference, which would impair its function. Therefore, by including beryllium and / or a beryllium alloy in the housing 2, a fuel cell 1 that can be used in outer space can be provided.

[0075] The Vickers hardness of beryllium is 1670 MPa, which is higher than the Vickers hardness of copper (369 MPa). Therefore, beryllium is harder than copper. Furthermore, a housing 2 containing beryllium is more resistant to scratches than a copper housing and has excellent durability. Similar properties can be expected from a housing 2 containing a beryllium alloy.

[0076] Fuel cells used in outer space may be at risk of collision with debris approaching at high speed. The housing 2 containing beryllium and / or a beryllium alloy has high Vickers hardness, and therefore can prevent damage caused by debris and loss of functionality. Therefore, by including beryllium and / or a beryllium alloy in the housing 2, it is possible to provide a fuel cell 1 that can be used in outer space.

[0077] Beryllium has a melting point of 1560 K, which is higher than the melting point of copper (1357.77 K). This prevents the casing 2 from melting even when the electrochemical reaction in the fuel cell 1 is carried out at a high temperature. Therefore, a casing 2 containing beryllium has better durability and is more resistant to high temperatures than a copper casing. Similar properties can be expected from a casing 2 containing a beryllium alloy.

[0078] The thermal expansion coefficient of beryllium is 11.3 x 10 at 25°C. －６ [1 / K], and the thermal expansion coefficient of copper (16.5 × 10 －６ [1 / K]. Therefore, the housing 2 containing beryllium is less susceptible to deformation due to temperature changes than a copper housing, and has excellent durability. Similar characteristics can be expected for beryllium alloys.

[0079] Fuel cells used in space can reach temperatures as high as 120°C when exposed to sunlight. Fuel cells used in space can also reach temperatures as low as -170°C when not exposed to sunlight. Therefore, fuel cells used in space can be used over a wide temperature range, including both low and high temperatures. Fuel cells used over a wide temperature range can be at risk of being deformed and losing their functionality due to temperature changes.

[0080] The housing 2 containing beryllium and / or a beryllium alloy has a low thermal expansion coefficient, and therefore can prevent deformation due to temperature changes, which would impair its functionality. Therefore, by including beryllium and / or a beryllium alloy in the housing 2, it is possible to provide a fuel cell 1 that can be used in outer space.

[0081] Iron, nickel, chromium, copper, and the like are excellent in Young's modulus and modulus of rigidity, but have a large specific gravity at a temperature of 25°C and a pressure of 1013 hPa (iron: 7.87 g / cm ３ , nickel 8.90 g / cm ３ , chromium 7.20 g / cm ３ , copper 8.96g / cm ３ ), beryllium (specific gravity 1.85 g / cm ３ ) is not lightweight compared to the

[0082] Alkali metals such as lithium and sodium and alkaline earth metals such as magnesium and calcium are highly reactive to oxygen and / or water, and there is a risk of them reacting with the oxygen-containing gas used in the fuel cell and / or water, which is a product of the electrochemical reaction in the fuel cell. In addition, alkali metals and alkaline earth metals have lower Young's modulus, modulus of rigidity, etc. than beryllium, and also have lower toughness.

[0083] Beryllium has a low specific gravity and is lightweight. The surface of beryllium is passivated in an oxygen atmosphere, which reduces the risk of reacting with oxygen. When beryllium comes into contact with water, the surface is covered with beryllium hydroxide. Beryllium hydroxide has low solubility in water, which reduces the risk of reacting with water. Furthermore, as mentioned above, beryllium has excellent durability indicators.

[0084] Therefore, since the housing 2 contains beryllium and / or a beryllium alloy, it is possible to construct a fuel cell 1 that is lighter and more durable than a fuel cell whose housing is made of copper.

[0085] Although not a required aspect, the beryllium alloy contained in the housing 2 preferably contains 90% or more beryllium in atomic ratio. Since the beryllium alloy contained in the housing 2 contains 90% or more beryllium in atomic ratio, the beryllium alloy can be made an even lighter alloy similar to beryllium. Therefore, the housing 2 containing the beryllium alloy can be made even lighter.

[0086] Furthermore, since the beryllium alloy contained in the housing 2 contains 90% or more beryllium in atomic ratio, the beryllium alloy can be made into an alloy with even greater durability, similar to beryllium, and therefore the durability of the housing 2 containing the beryllium alloy can be further improved.

[0087] Although not an essential aspect, the beryllium alloy contained in the housing 2 preferably contains an element whose specific gravity as a simple substance at a temperature of 25° C. and a pressure of 1013 hPa is approximately the same as or less than that of titanium.

[0088] The beryllium alloy contained in the housing 2 contains an element whose specific gravity as a simple substance at a temperature of 25°C and a pressure of 1013 hPa is approximately the same as or less than that of titanium, making it possible to make the beryllium alloy an even lighter alloy.As a result, the housing 2 containing the beryllium alloy can be made even lighter.

[0089] Although not an essential aspect, it is preferable that the housing 2 contains a high-entropy alloy having five or more elements, each of which has an atomic ratio of 50% or less.

[0090] High-entropy alloys are known to have excellent heat resistance, high-temperature strength, corrosion resistance, etc. In other words, high-entropy alloys are alloys with excellent durability. Therefore, by including a high-entropy alloy in the housing 2, the durability of the housing 2 can be further improved.

[0091] Regarding the alloy contained in the housing 2, for example, an Mg-based alloy is a practical lightweight alloy. However, Mg-based alloys usually have room for further improvement in terms of strength.

[0092] Regarding the enhancement of strength in Mg-based alloys, Yoshito Kawamura has disclosed a relatively high-strength Mg alloy having a crystal structure named LPSO structure (Long Period Stacking Ordered Structure) in "Characteristics and Future Prospects of LPSO-type Magnesium Alloys" (Materia, Vol. 54, No. 2 (2015) pp. 44-49.). The above-mentioned document describes a Mg alloy obtained by extruding and solidifying rapidly solidified powder produced by high-pressure gas atomization. ９７ Zn １ Y ２ (at %) alloy exhibits a yield strength of 610 MPa.

[0093] The above-mentioned literature discloses Mg-M-RE alloys, which exhibit similar high strength properties as similar LPSO-type Mg alloys, where M represents a metal element (Co, Nl, Cu, Zn) and RE represents a rare earth element (Y, Gd, Tb, Dy, Ho, Er, Tm).

[0094] In addition, there have been attempts to realize Mg alloys that combine high flame retardancy, high strength, and high ductility by reducing the amounts of Al and Ca added to Mg-Al-Ca alloys, which are primarily standardized as die-casting materials. However, the development of technology to scale up these alloys for social implementation is still underway, and there is room for further improvement in terms of practical application.

[0095] Michael C. Cao, Jian Wei Yeh, Peler K. Liaw, and Yong Zhangi disclose metallic materials such as high-entropy alloys (High-Entropy Alloys) composed of five or more main elements in "High-Entropy Alloys: Fundamentals and Applications" (ISBN 978-3-319-27011-1, DOI 10.1007 / 978-3-319-27013-5, Springer International Publishing, Switzerland, (2016)).

[0096] It is known that the strength of Inconel 718 alloy, an example of a practical heat-resistant alloy (Ni-based superalloy), decreases at high temperatures of 600°C or higher, and the yield strength falls below 200 MPa at temperatures exceeding 1000°C. ２０ Nb ２０ Mo ２０ Ta ２０ W ２０ It states that the strength loss at high temperatures is slight, and that the yield strength is about 1.5 times that of Inconel 718 alloy at 800°C and about 5.5 times that of Inconel 718 alloy at 1000°C. Therefore, by using a high-entropy alloy composed of five or more main elements, even higher strength can be achieved.

[0097] However, high-entropy alloy V ２０ Nb ２０ Mo ２０ Ta ２０ W ２０ has a density of 10 g / cm3 at room temperature ３ It is a relatively heavy alloy containing multiple of the above elements, and there is room for further improvement in terms of reducing density.

[0098] Although not an essential aspect, the housing 2 contains five or more elements selected from the group consisting of Li, Be, B, Na, Mg, Al, Si, P, S, K, Ca, Sc, Ti, Rb, Sr, Y, Ba, Zn, Sn, Ce, Nd, Sm, and Gd, and the atomic ratio of each of the five or more elements is approximately the same, or the atomic ratio of any one or more of the five or more elements is in the range of 5 to 35%, and the density is 2.5 g / cm ３ Preferably, the alloy comprises a high entropy alloy that is:

[0099] Li, Be, B, Na, Mg, Al, Si, P, S, K, Ca, Sc, Ti, Rb, Sr, Y, Ba, Zn, Sn, Ce, Nd, Sm, and Gd are relatively light elements. When the high-entropy alloy contains five or more of the above-mentioned light elements, it can achieve a density of 2.5 g / cm. ３ Densities as low as

[0100] A high-entropy alloy contains five or more elements, and the atomic ratios of each of the five or more elements are approximately the same, or the atomic ratio of at least one of the five or more elements is in the range of 5 to 35%, thereby stabilizing the mixed state of atoms in the alloy and achieving high lattice strain due to the mutual influence of different atoms. Furthermore, the high lattice strain reduces the thermal diffusivity (temperature diffusion coefficient) up to high temperatures. Furthermore, the high lattice strain retards atomic diffusion, increasing hardness (strength) and reducing its temperature dependence. Therefore, by including the above-mentioned high-entropy alloy in the housing 2, the durability and / or light weight of the housing 2 can be further improved.

[0101] Although not an essential aspect, the housing 2 contains three or more elements of Al, Ca, Zn, and Sn, and has a density of 2.5 g / cm ３ The alloy preferably includes the following Mg-Li alloys, which contain 8 to 11% by mass of Li relative to Mg, and have a mixed structure of a structure having a close-packed hexagonal lattice crystal structure and a structure including a body-centered cubic lattice crystal structure, or a structure consisting of a body-centered cubic lattice crystal structure.

[0102] Because the Mg-Li alloy has the above-mentioned characteristics, it is possible to reduce the amount of rare Li used while achieving a concentration of 2.5 g / cm ３The following low density can be achieved. Durability can also be improved. Therefore, by including the Mg—Li alloy in the housing 2, the durability and / or lightness of the housing 2 can be further improved.

[0103] The high-entropy alloy and / or Mg—Li alloy described above is a cast material, a forged material, a rolled material, a thermomechanically treated material, or a powder material, and has a density of 2.5 g / cm ３ It is preferable that:

[0104] The high-entropy alloy and / or Mg—Li alloy are lightweight and have the various forms described above, so that the housing 2 can be easily constructed.

[0105] Although not essential, the housing 2 preferably comprises a composite material having ceramic and aluminum.

[0106] It is known that a composite material containing ceramic and aluminum can simultaneously achieve light weight, a high Young's modulus, a low coefficient of thermal expansion, high thermal conductivity, and high fracture toughness. In other words, a composite material containing ceramic and aluminum is a composite material that is both lightweight and highly durable. By including a composite material containing ceramic and aluminum in the housing 2, the housing 2 can be made even lighter and its durability can be further increased.

[0107] In a fuel cell having multiple cells separated by separators inside a housing, the housing, separators, and / or cells may have complex shapes. To form a complex-shaped body, a technique for forming a body by welding multiple parts having relatively simple shapes is used. The technique for forming a body by welding can form a complex-shaped body, such as a shape with protrusions, or a shape with internal recesses and / or holes. However, in the technique for forming a body by welding, the strength of the welded portion may be lower than that of other portions. Therefore, the technique for forming a body by welding leaves room for further improvement in durability.

[0108] Metal 3D printers are known that form metal additively molded objects using techniques such as sintering and laminating metal powder with a laser and / or electron beam, cutting and laminating sheet metal, and sintering and laminating metal wire with a laser and / or electron beam. Using a metal 3D printer allows for the formation of metal additively molded objects without welding, thereby preventing the strength of welded areas from being lower than that of other areas. Therefore, metal additively molded objects formed by a metal 3D printer can achieve superior durability compared to objects formed by welding.

[0109] Although not a required aspect, it is preferable that the housing 2 is an additively manufactured body using a metal 3D printer. This allows the housing 2 to achieve greater durability than a housing formed by welding. The metal 3D printer is not particularly limited, and may be, for example, one or more of a 3D additive manufacturing method using spherical powder or rod-shaped wire, a powder sintering method, a powder melting method, a powder bonding method, a sheet lamination method, a DMD (Directed Metal Deposition) method, a DED (Directed Energy Deposition) method, and a wire payout method.

[0110] The method for producing the spherical powder is not particularly limited, and may be, for example, a method using one or more of a gas and water atomizer for producing powder for 3D additive manufacturing, a plasma rotating electrode powder producing machine, a rotating disk atomizer, and other powder producing machines for producing spherical powder.

[0111] [Separator 3] The separator 3 is housed in the housing 2 and separates two or more cells 4. There are no particular limitations on the separator 3, and it may be a separator used in conventional fuel cells. By providing the separator 3, it is possible to separate two or more cells 4. This allows the two or more cells 4 to generate electricity using fuel without interfering with each other's operation.

[0112] The separator 3 may be a separator that separates two or more cells 4 with one separator, or a separator that separates two or more cells 4 with multiple separators. When the separator 3 is a separator that separates two or more cells 4 with one separator, the structure of the separator 3 can be simplified. When the separator 3 is a separator that separates two or more cells 4 with multiple separators, it can be made easier to replace part of the separator, etc.

[0113] Although not an essential aspect, the separator 3 may be a separator that separates one or more cells 4 from one or more components of the fuel cell 1, such as the housing 2 (for example, the first separator 3a in FIG. 2 ). This separates the components of the fuel cell 1 from the cells 4, allowing them to generate electricity using fuel without interfering with each other's operations.

[0114] The separator 3 preferably contains beryllium and / or a beryllium alloy. Fuel cells used in space are required to be lightweight due to payload limitations imposed by rockets and other vehicles that launch fuel cells from Earth. Space can be subject to extreme temperature conditions, both high and low. Furthermore, repairs and other procedures are more difficult for fuel cells used in space than for devices used on Earth. For these reasons, fuel cells used in space are required to have excellent durability.

[0115] Similar to the beryllium-containing housing 2, the beryllium-containing separator 3 can be constructed to be lightweight. Similar properties can be expected from the beryllium alloy-containing separator 3.

[0116] Similar to the beryllium-containing housing 2, the beryllium-containing separator 3 has excellent durability that can prevent breakage due to bending. Similar properties can be expected for the beryllium alloy-containing separator 3.

[0117] Similar to the beryllium-containing casing 2, the beryllium-containing separator 3 has excellent durability that can prevent loss of function due to deformation caused by external forces, etc. Similar characteristics can be expected from the beryllium alloy-containing separator 3.

[0118] Similar to the beryllium-containing housing 2, the beryllium-containing separator 3 is more scratch-resistant and durable than a copper separator. Similar properties can be expected from a beryllium alloy-containing separator 3.

[0119] Similar to the beryllium-containing casing 2, the beryllium-containing separator 3 is more resistant to high temperatures and has superior durability than a copper separator. Similar properties can be expected from a beryllium alloy-containing separator 3.

[0120] Similar to the beryllium-containing casing 2, the beryllium-containing separator 3 is less susceptible to deformation due to temperature changes than a copper separator and has excellent durability. Similar properties can be expected from beryllium alloys.

[0121] Therefore, since the separator 3 contains beryllium and / or a beryllium alloy, it is possible to construct a fuel cell 1 that is lighter and more durable than a fuel cell in which the separator is made of copper.

[0122] Although not essential, the beryllium alloy contained in the separator 3 preferably contains 90% or more beryllium by atomic ratio. Because the beryllium alloy contained in the separator 3 contains 90% or more beryllium by atomic ratio, the beryllium alloy can be made an even lighter alloy similar to beryllium. Therefore, the separator 3 containing the beryllium alloy can be made even lighter.

[0123] Furthermore, because the beryllium alloy contained in the separator 3 contains 90% or more beryllium by atomic ratio, the beryllium alloy can be made into an alloy with even greater durability, similar to beryllium, and therefore the durability of the separator 3 containing the beryllium alloy can be further improved.

[0124] Although not essential, the beryllium alloy contained in the separator 3 preferably contains an element whose specific gravity as a simple substance at a temperature of 25° C. and a pressure of 1013 hPa is approximately the same as or less than that of titanium.

[0125] The beryllium alloy contained in separator 3 contains an element whose specific gravity as a simple substance at a temperature of 25°C and a pressure of 1013 hPa is approximately the same as or less than that of titanium, making it possible to make the beryllium alloy an even lighter alloy.As a result, separator 3 containing the beryllium alloy can be made even lighter.

[0126] Although not an essential aspect, it is preferable that the separator 3 contains a high-entropy alloy. By including a high-entropy alloy in the separator 3, the durability of the separator 3 can be further improved. The high-entropy alloy is not particularly limited, and may be the same as that of the housing 2.

[0127] Although not an essential aspect, the separator 3 contains three or more elements of Al, Ca, Zn, and Sn, and has a density of 2.5 g / cm ３ The separator 3 preferably contains the following Mg—Li alloy, which has a ratio of Li to Mg of 8 to 11% by mass and has a mixed structure of a structure including a close-packed hexagonal lattice crystal structure and a body-centered cubic lattice crystal structure, or a structure consisting of a body-centered cubic lattice crystal structure. By containing such an Mg—Li alloy in the separator 3, the durability of the separator 3 can be further improved.

[0128] Although not an essential aspect, it is preferable that the separator 3 includes a composite material having ceramic and aluminum. By including a composite material having ceramic and aluminum in the separator 3, the separator 3 can be made even lighter and its durability can be further improved.

[0129] Although not a required aspect, the separator 3 is preferably an additively manufactured body produced by a metal 3D printer. This allows the separator 3 to achieve greater durability than a separator formed by welding. The metal 3D printer is not particularly limited, and may be, for example, one or more of a 3D additive manufacturing method using spherical powder or rod-shaped wire, a powder sintering method, a powder melting method, a powder bonding method, a sheet lamination method, a DMD (Directed Metal Deposition) method, a DED (Directed Energy Deposition) method, and a wire payout method.

[0130] The method for producing the spherical powder is not particularly limited, and may be, for example, a method using one or more of a gas and water atomizer for producing powder for 3D additive manufacturing, a plasma rotating electrode powder producing machine, a rotating disk atomizer, and other powder producing machines for producing spherical powder.

[0131] [Cell 4] Cell 4 is a cell capable of generating electricity using fuel. There are no particular limitations on the cell 4, and it may be a cell of a fuel cell in the prior art. The number of cells 4 is not particularly limited as long as it is two or more. By including two or more cells 4, electricity can be generated with a larger potential difference than when power is generated using one cell 4.

[0132] The cell 4 may be, for example, a solid oxide fuel cell (SOFC) cell, an alkaline fuel cell (AFC) cell, a molten carbonate fuel cell (MCFC) cell, a phosphoric acid fuel cell (PAFC) cell, a proton-exchange membrane fuel cell (PEMFC, polymer electrolyte membrane, PEM) cell, or a cell including one or more of these cells.

[0133] FIG. 3 is an enlarged schematic view showing the periphery of cell 4 of the fuel cell 1 shown in FIG. 2. FIG. 4 is an enlarged schematic view showing the periphery of cell 4 of a flat-plate solid oxide fuel cell. FIG. 5 is an enlarged schematic view showing the periphery of cell 4 of a cylindrical solid oxide fuel cell. FIG. 6 is an enlarged schematic view showing the periphery of cell 4 of an alkaline electrolyte fuel cell. FIG. 7 is an enlarged schematic view showing the periphery of cell 4 of a molten carbonate fuel cell. FIG. 8 is an enlarged schematic view showing the periphery of cell 4 of a phosphoric acid fuel cell. The configuration of cell 4 will be described below with reference to FIGS. 3-7 as necessary.

[0134] The cell 4 has a fuel flow channel 41 , a fuel electrode 42 , an electrolyte 43 , an oxygen electrode 44 , and an oxygen flow channel 45 .

[0135] The shape of the cells 4 is not particularly limited, and may be flat (FIGS. 3, 4, 7, and 8) or cylindrical (FIGS. 5 and 6).

[0136] When the cells 4 are solid oxide fuel cells, the cells 4 preferably include flat-type cells 4 ( FIG. 4 ) and / or cylindrical-type cells 4 ( FIG. 5 ). When the cells 4 include the flat-type cells 4 shown in FIG. 4 , the fuel cell 1 can be constructed by stacking flat-type cells 4. This makes it easier to manufacture the fuel cell 1. When the cells 4 include the cylindrical cells 4 shown in FIG. 5 , the fuel electrode 42, electrolyte 43, oxygen electrode 44, and oxygen flow channel 45 can have a cylindrical shape that is highly pressure-resistant. This improves durability when the fuel and / or oxygen pressure is high.

[0137] When the cell 4 is an alkaline electrolyte fuel cell, the cell 4 preferably includes a cylindrical cell 4 (FIG. 6). By including the cylindrical cell 4 shown in FIG. 6, the cell 4 can be constructed by filling a space defined by two or more separators 3 and the like with an alkaline electrolyte to form an electrolyte 43', and then arranging a cylindrical fuel electrode 42 and an oxygen electrode 44 in the space. This makes it possible to manufacture the fuel cell 1 even more easily, even if the electrolyte 43' is a liquid alkaline electrolyte.

[0138] When the cell 4 is a molten carbonate fuel cell cell, the cell 4 preferably comprises a flat plate-type cell 4 (FIG. 7) having a fuel electrode 42′ including a porous body, an electrolyte 43″ including a porous body, and an oxygen electrode 44′ including a porous body. When each member constituting the cell 4 includes a porous body, the electrolyte 43″ can be more reliably held, even if the electrolyte 43″ is a liquid molten carbonate. This can improve the performance of the fuel cell 1.

[0139] When the cell 4 is a phosphoric acid fuel cell, the cell 4 preferably includes a flat-plate cell 4 (FIG. 8) having a ribbed anode 42 and a ribbed cathode 44. The ribbed anode 42 and cathode 44 can increase the contact area between the electrolyte 43', which is a liquid phosphoric acid solution, and the fuel and / or oxygen, thereby improving the performance of the fuel cell 1.

[0140] When the cells 4 are polymer electrolyte fuel cells, the cells 4 preferably include flat-plate type cells 4 (FIG. 3). By including the flat-plate type cells 4 shown in FIG. 3, the fuel cell 1 can be constructed by stacking the flat-plate type cells 4. This makes it possible to manufacture the fuel cell 1 even more easily.

[0141] [Fuel Flow Channel 41] The fuel flow channel 41 is a flow channel for fuel that functions as a reducing agent in power generation using an electrochemical reaction in the cell 4. The fuel flow channel 41 is defined by the fuel electrode 42 and one or more of the components of the fuel cell 1, exemplified by the casing 2, the separator 3, and the electrolyte 43. The cell 4 has the fuel flow channel 41, which allows fuel to be supplied to the fuel electrode 42.

[0142] The fuel flow path 41 is configured to be able to supply fuel supplied from an external source to the fuel electrode 42. This allows the cell 4 to continuously generate power using fuel supplied from an external source. Therefore, it is possible to provide a fuel cell 1 that can continuously extract a larger amount of power than a primary battery and / or a secondary battery.

[0143] The fuel flow path 41 is preferably configured so that the fuel after power generation can be discharged to the outside of the fuel flow path 41. This can prevent the fuel after power generation from remaining in the fuel flow path 41, which would otherwise reduce the power generation efficiency of the cell 4.

[0144] When the cell 4 is a solid oxide fuel cell, an alkaline electrolyte fuel cell, and / or a molten carbonate fuel cell, the fuel flow path 41 is preferably a flow path that can discharge water generated at the anode 42. This can prevent a decrease in power generation efficiency due to water generated at the anode 42 in the cell 4 of a solid oxide fuel cell, an alkaline electrolyte fuel cell, and / or a molten carbonate fuel cell.

[0145] When the cell 4 is a solid oxide fuel cell cell, the fuel flow path 41 is preferably a flow path that can supply carbon monoxide to the fuel electrode 42. This allows the carbon monoxide to react with oxygen ions at the fuel electrode 42 of the solid oxide fuel cell.

[0146] When the cell 4 is a molten carbonate fuel cell cell, the fuel flow path 41 is preferably a flow path that can discharge carbon dioxide generated at the fuel electrode 42. This can prevent a decrease in power generation efficiency due to carbon dioxide generated at the fuel electrode 42 in the cell 4 of the molten carbonate fuel cell.

[0147] When the cell 4 is a polymer electrolyte fuel cell cell, the fuel flow path 41 is preferably a flow path that can supply water to the fuel electrode 42. This can prevent the fuel electrode 42 in the polymer electrolyte fuel cell cell 4 from drying out and reducing the power generation efficiency.

[0148] [Anode 42] The anode 42 is an anode that can realize a reaction that supplies electrons to the outside by cooperating with the electrolyte 43 and the oxygen electrode 44 using the fuel supplied from the fuel flow channel 41. The anode 42 is not particularly limited and may be an anode of a conventional fuel cell. By having the anode 42 in the cell 4, electrons can be supplied to the outside using the fuel supplied from the fuel flow channel 41. This allows the cell 4 to generate power using the fuel.

[0149] The anode 42 preferably contains a catalyst that promotes a reaction that uses fuel to supply electrons to the outside, thereby further increasing the power generation efficiency of the cell 4. There are no particular limitations on the catalyst, and it may be any catalyst used in anodes of fuel cells of the prior art.

[0150] The anode 42 preferably includes a diffusion structure that allows the fuel to diffuse. This allows the fuel to diffuse and the reaction that uses the fuel to supply electrons to the outside to occur more efficiently. This further increases the power generation efficiency of the cell 4.

[0151] When the cell 4 is a solid oxide fuel cell cell, the fuel electrode 42 is preferably capable of receiving oxygen ions from the oxygen electrode 44 via the electrolyte 43. This allows the fuel electrode 42 to receive negatively charged oxygen ions from the oxygen electrode 44 and supply electrons to the outside by reducing the oxygen ions with fuel. When the cell 4 is a solid oxide fuel cell cell and the fuel flow path 41 is a flow path that can supply carbon monoxide to the fuel electrode 42, the fuel electrode 42 is preferably capable of reacting carbon monoxide with oxygen ions. This allows the fuel electrode 42 to supply electrons to the outside by reacting carbon monoxide with oxygen ions.

[0152] When the cell 4 is an alkaline electrolyte fuel cell cell, the fuel electrode 42 is preferably capable of receiving hydroxide ions from the oxygen electrode 44 via the electrolyte 43. This allows the fuel electrode 42 to receive negatively charged hydroxide ions from the oxygen electrode 44 and supply electrons to the outside by reducing the hydroxide ions with fuel.

[0153] When the cell 4 is an alkaline electrolyte fuel cell cell, the anode 42 may contain beryllium and / or a beryllium alloy. This can reduce the weight of the anode 42 and increase its durability. The electrical resistivity of beryllium is 55.3 nΩ·m at 100°C, which is lower than the electrical resistivity of iron (147 nΩ·m). Therefore, by including beryllium in the anode 42, the electrical resistance of the anode 42 can be made lower than that of an iron anode, thereby improving power generation efficiency. A similar effect can be expected with a beryllium alloy.

[0154] When the cell 4 is a cell of a molten carbonate fuel cell, the fuel electrode 42 is preferably capable of receiving carbonate ions from the oxygen electrode 44 via the electrolyte 43. This allows the fuel electrode 42 to receive negatively charged carbonate ions from the oxygen electrode 44 and supply electrons to the outside by reducing the carbonate ions with the fuel.

[0155] When the cell 4 is a phosphoric acid fuel cell and / or a polymer electrolyte fuel cell, the fuel electrode 42 is preferably capable of supplying hydrogen ions generated by reducing the fuel to the oxygen electrode 44 via the electrolyte 43. This allows positively charged hydrogen ions to be supplied to the oxygen electrode 44, and electrons to be supplied to the outside.

[0156] [Electrolyte 43] The electrolyte 43 is an electrolyte capable of mediating the movement of ions between the fuel electrode 42 and the oxygen electrode 44. There are no particular limitations on the electrolyte 43, and it may be an electrolyte used in conventional fuel cells. By including the electrolyte 43 in the cell 4, the electrolyte 43 can mediate the movement of ions between the fuel electrode 42 and the oxygen electrode 44, allowing the fuel electrode 42 to supply electrons to the outside.

[0157] When the cell 4 is a solid oxide fuel cell cell, the electrolyte 43 preferably contains a solid oxide capable of mediating the movement of oxygen ions, such as yttria-stabilized zirconia, scandia-stabilized zirconia, gadolinium-doped ceria, etc. This allows the solid oxide to mediate the movement of oxygen ions, allowing the anode 42 to supply electrons to the outside.

[0158] When the cell 4 is an alkaline electrolyte fuel cell cell, the electrolyte 43 preferably contains an alkaline aqueous solution, such as a potassium hydroxide aqueous solution, so that the alkaline aqueous solution mediates the movement of hydroxide ions, allowing the anode 42 to supply electrons to the outside.

[0159] When the cell 4 is a molten carbonate fuel cell cell, the electrolyte 43 preferably contains one or more molten carbonates, such as lithium carbonate and sodium carbonate, etc. This allows the molten carbonate to mediate the movement of carbonate ions, allowing the anode 42 to supply electrons to the outside.

[0160] When the cell 4 is a phosphoric acid fuel cell cell, the electrolyte 43 preferably contains an aqueous phosphoric acid solution, which mediates the movement of hydrogen ions, allowing the anode 42 to supply electrons to the outside.

[0161] When the cell 4 is a polymer electrolyte fuel cell, the electrolyte 43 preferably contains an ion-conductive polymer (ion exchange resin). This allows the ion exchange resin to mediate the movement of hydrogen ions, allowing the anode 42 to supply electrons to the outside. The ion exchange resin is preferably an ion exchange membrane made of ion exchange resin in a membrane form. This shortens the migration distance of the hydrogen ions, allowing them to migrate more easily. This can therefore improve the power generation efficiency of the cell 4.

[0162] [Oxygen electrode 44] The oxygen electrode 44 is a cathode that can generate current by an electrochemical reaction using oxygen supplied from the oxygen flow path 45 in cooperation with the fuel electrode 42 and the electrolyte 43. There are no particular limitations on the oxygen electrode 44, and it may be an oxygen electrode of a conventional fuel cell. By having the oxygen electrode 44 in the cell 4, current can be generated by an electrochemical reaction using oxygen supplied from the oxygen flow path 45. This allows the cell 4 to generate power using fuel.

[0163] The oxygen electrode 44 preferably contains a catalyst that promotes an electrochemical reaction using oxygen, thereby further increasing the power generation efficiency in the cell 4. There are no particular limitations on the catalyst, and it may be any catalyst used in oxygen electrodes of conventional fuel cells.

[0164] The oxygen electrode 44 preferably includes a diffusion structure that allows oxygen to diffuse. This allows oxygen to be diffused and electrochemical reactions using oxygen to occur more efficiently, thereby further increasing the power generation efficiency of the cell 4.

[0165] When the cell 4 is a solid oxide fuel cell cell, the oxygen electrode 44 is preferably capable of supplying oxygen ions to the fuel electrode 42 via the electrolyte 43. This allows the supply of negatively charged oxygen ions to the fuel electrode 42, thereby generating a current.

[0166] When the cell 4 is an alkaline electrolyte fuel cell cell, the oxygen electrode 44 is preferably capable of supplying hydroxide ions to the fuel electrode 42 via the electrolyte 43. This allows negatively charged hydroxide ions to be supplied to the fuel electrode 42, thereby generating a current.

[0167] When the cell 4 is an alkaline electrolyte fuel cell cell, the oxygen electrode 44 may contain beryllium and / or a beryllium alloy. This can reduce the weight of the oxygen electrode 44 and increase its durability. The electrical resistivity of beryllium is 55.3 nΩ·m at 100°C, which is lower than the electrical resistivity of iron (147 nΩ·m). Therefore, by including beryllium in the oxygen electrode 44, the electrical resistance of the oxygen electrode 44 can be made lower than that of an iron oxygen electrode, thereby improving power generation efficiency. A similar effect can be expected with a beryllium alloy.

[0168] When the cell 4 is a molten carbonate fuel cell cell, the oxygen electrode 44 is preferably capable of supplying carbonate ions to the fuel electrode 42 via the electrolyte 43. This allows negatively charged carbonate ions to be supplied to the fuel electrode 42, thereby generating a current.

[0169] When the cell 4 is a phosphoric acid fuel cell and / or a polymer electrolyte fuel cell, the oxygen electrode 44 is preferably capable of receiving hydrogen ions from the fuel electrode 42 via the electrolyte 43. This allows the oxygen electrode 44 to receive positively charged hydrogen ions from the fuel electrode 42 and generate an electric current.

[0170] [Oxygen flow path 45] The oxygen flow path 45 is a flow path for a gas containing oxygen that functions as an oxidant in power generation using an electrochemical reaction in the cell 4. The oxygen flow path 45 is defined by the oxygen electrode 44 and one or more of the components of the fuel cell 1, exemplified by the casing 2, the separator 3, and the electrolyte 43. By having the oxygen flow path 45 in the cell 4, oxygen can be supplied to the oxygen electrode 44.

[0171] The oxygen flow path 45 is configured to be able to supply oxygen contained in gas supplied from the outside to the oxygen electrode 44. This allows the cell 4 to continuously generate power using the oxygen contained in the gas supplied from the outside. Therefore, it is possible to provide a fuel cell 1 that can continuously extract a larger amount of power than a primary battery and / or a secondary battery.

[0172] The oxygen flow path 45 is preferably configured so that the gas after power generation can be discharged to the outside of the oxygen flow path 45. This can prevent the gas after power generation from remaining in the oxygen flow path 45 and reducing the power generation efficiency of the cell 4.

[0173] When the cell 4 is an alkaline electrolyte fuel cell cell, the oxygen flow path 45 is preferably a flow path that can supply a gas that does not contain carbon dioxide to the oxygen electrode 44. This can prevent the alkaline aqueous solution contained in the electrolyte 43 from reacting with carbon dioxide, which would otherwise reduce the power generation efficiency of the cell 4.

[0174] When the cell 4 is a molten carbonate fuel cell cell, the oxygen flow path 45 is preferably a flow path that can supply carbon dioxide to the oxygen electrode 44. This makes it possible to supply carbonate ions to the electrolyte 43 of the molten carbonate fuel cell.

[0175] When the cell 4 is a phosphoric acid fuel cell and / or a polymer electrolyte fuel cell, the oxygen flow path 45 is preferably a flow path that can discharge water generated at the oxygen electrode 44. This can prevent a decrease in power generation efficiency due to water generated at the oxygen electrode 44 in the cell 4 of a phosphoric acid fuel cell and / or a polymer electrolyte fuel cell.

[0176] [Fuel] The fuel is not particularly limited and may be any fuel used in conventional fuel cells. The fuel preferably contains hydrogen-containing compounds and / or elemental hydrogen, such as methane and methanol. This allows hydrogen and / or hydrogen-containing compounds to be reduced at the anode 42, thereby supplying hydrogen ions to the electrolyte 43.

[0177] [Power Output Terminal] The fuel cell 1 preferably includes a power output terminal (not shown) that can output the power generated in the cells 4. This allows the power generated in the cells 4 to be output and used in various devices.

[0178] Although not essential, the power terminal preferably contains beryllium and / or a beryllium alloy. This can reduce the weight of the power terminal and increase its durability. Furthermore, by including beryllium in the power terminal, the electrical resistance of the power terminal can be made lower than that of an iron power terminal, thereby improving power generation efficiency. Similar effects can be expected for beryllium alloys.

[0179] [Other Components] Figure 9 is a schematic diagram showing the fuel cell 1 of this embodiment as viewed obliquely from above. Although not an essential feature, the fuel cell 1 preferably includes a fuel supply unit (e.g., symbol F in Figure 9) capable of supplying fuel to the fuel flow path 41. This allows fuel to be supplied to the fuel flow path 41 and continuous power generation can be achieved. The fuel supply unit is not particularly limited and may be, for example, a fuel supply unit including a conventional fuel container. Although not an essential feature, the fuel supply unit preferably includes beryllium and / or a beryllium alloy. This can reduce the weight of the fuel supply unit and increase its durability.

[0180] Although not an essential aspect, the fuel cell 1 preferably includes an oxygen supply unit (e.g., symbol A in FIG. 9 ) capable of supplying oxygen-containing gas to the oxygen flow path 45. Space is essentially a vacuum, making it difficult to obtain oxygen-containing gas. By including an oxygen supply unit in the fuel cell 1, oxygen-containing gas can be supplied to the oxygen flow path 45 even in space. The oxygen supply unit is not particularly limited, and may be, for example, a conventional oxygen supply unit including an oxygen container.

[0181] Although not an essential feature, the fuel cell 1 preferably includes a fuel reformer (not shown) that reforms the fuel supplied to the fuel flow path 41 into a form suitable for power generation in the cells 4. This can increase the power generation efficiency in the cells 4 by using the reformed fuel.

[0182] Although not an essential feature, the fuel cell 1 preferably includes an oxygen reformer (not shown) that reforms the oxygen-containing gas supplied to the oxygen flow path 45 into a form suitable for power generation in the cell 4. This can increase the power generation efficiency in the cell 4 by using the reformed gas.

[0183] Fuel cells used in space can reach high temperatures when exposed to sunlight, and can reach low temperatures when not exposed to sunlight. Thus, fuel cells used in space can be used over a wide temperature range, including both low and high temperatures.

[0184] It is known that the power generation efficiency of a fuel cell varies depending on the cell temperature. If a fuel cell is to be used over a wide temperature range, the power generation efficiency may vary and decrease depending on the cell temperature.

[0185] Although not a required feature, the fuel cell 1 preferably includes a temperature control unit (e.g., symbol C in FIG. 9 ) that controls the temperature of the components of the fuel cell 1, such as the cells 4. This allows the temperatures of the components of the fuel cell 1 to be controlled within a predetermined range that provides high power generation efficiency, even when the fuel cell 1 is used in outer space. This therefore increases the power generation efficiency of the fuel cell 1.

[0186] Although not an essential feature, the fuel cell 1 preferably includes an exhaust unit (e.g., symbol E in FIG. 9 ) capable of exhausting fuel after power generation. This allows the fuel after power generation to be exhausted and new fuel to be supplied to the cells 4.

[0187] <Example of Use> An example of use of the fuel cell 1 according to this embodiment will be described.

[0188] [Transportation into outer space] A user of the fuel cell 1 uses a rocket or the like to launch the fuel cell 1 and a device or the like that uses the power generated by the fuel cell 1 (for example, a rover capable of exploring planets and / or satellites, a probe capable of exploring planets, satellites and / or small celestial bodies, and an artificial satellite) into outer space. Because the casing 2 and / or the separator 3 contain beryllium and / or a beryllium alloy, the fuel cell 1 and the device or the like can be transported into outer space even if there is a limit to the weight that can be launched by the rocket.

[0189] [Temperature Control] The fuel cell 1 uses a temperature control unit to control the temperature of the cells 4 within a predetermined range that provides high power generation efficiency. This allows the temperature of the cells 4 to be controlled within a predetermined range that provides high power generation efficiency even when the temperature of the fuel cell 1 in space is low and / or high.

[0190] [Supply of fuel and oxygen] The fuel cell 1 supplies fuel to the fuel flow path 41. The fuel cell 1 supplies gas containing oxygen to the oxygen flow path 45. This causes an electrochemical reaction using the fuel and oxygen at the fuel electrode 42, electrolyte 43, and oxygen electrode 44, generating electricity.

[0191] [Utilization of Electric Power] Devices and the like that utilize the electric power generated by the fuel cell 1 extract and utilize the generated electric power from the power output terminal. By including beryllium and / or a beryllium alloy in the housing 2 and / or the separator 3, deformation due to temperature changes and damage due to debris can be prevented, and electric power can be supplied to the device for a long period of time.

[0192] <First Rocket Engine 111> FIG. 10 is a schematic piping diagram of the first rocket engine 111.

[0193] The first rocket engine 111 is an engine 100 that generates thrust by mixing and burning an oxidizer and a fuel. This first rocket engine 111 is a rocket engine of a so-called expander bleed cycle type, in which part of the fuel is used as a coolant for the combustor 1 and also as a driving medium for each turbopump that pressurizes and pumps the oxidizer and the fuel.

[0194] The first rocket engine 111 has an injector 1002 capable of injecting oxidizer and fuel, and is equipped with a combustor 1001 capable of combusting the oxidizer and fuel. Furthermore, the engine 100 is equipped with a piping system that supplies the oxidizer and fuel to the combustor 1001 and circulates them to each part of the first rocket engine 111, including a fuel supply line 1090 that supplies fuel to the combustor 1001, an oxidizer supply line 1091 that supplies the oxidizer to the combustor 1, and a cooling medium / turbo pump driving medium supply line 1092 that circulates the fuel to each part of the first rocket engine 111 as a cooling medium for cooling the combustor 1001.

[0195] The fuel supply line 1090 is composed of multiple pipes and connects a fuel tank (not shown) that stores liquid hydrogen (hereinafter referred to as "LH") as fuel to the injection unit 1031 of the combustor 1001, thereby constituting a fuel supply system. Similarly, the oxidizer supply line 1091 is composed of multiple pipes and connects an oxidizer tank (not shown) that stores liquid oxygen (hereinafter referred to as "LOx") as an oxidizer to the injection unit 1031 of the combustor 1001, thereby constituting an oxidizer supply system. The coolant / turbo pump driving medium supply line 1092 is composed of multiple pipes and branches off from the fuel supply line 1090 at one end, passes through a cooling passage 1033 in the wall of the combustion chamber 1003 of the combustor 1001, and is connected to the inside of the nozzle 1004 of the combustor 1001 at the other end, thereby constituting a coolant / driving medium supply system.

[0196] Furthermore, the first rocket engine 111 includes a fuel turbopump 1050 capable of pumping fuel to the combustor 1001 via a fuel supply line 1090, an oxidizer turbopump 1060 capable of pumping oxidizer to the combustor 1001 via an oxidizer supply line 1091, a mixer 1070 that cools the combustor 1001 and mixes vaporized fuel with liquid fuel, and an igniter 1080 that ignites the mixture of oxidizer and fuel.

[0197] The fuel turbo pump 1050 includes a compressor 1051 and a turbine 1052. The turbine 1052 is rotationally driven by hydrogen gas (hereinafter referred to as "GH") as fuel that has passed through the cooling passage 1033 and vaporized, thereby driving the compressor 1051, and the compressor 1051 pressurizes LH in the fuel supply line 1090 and sends it under pressure to the injector 1002. The oxidizer turbo pump 1060 includes a compressor 1061 and a turbine 1062. The turbine 1062 is rotationally driven by GH as fuel that has passed through the cooling passage 1033 and vaporized, thereby driving the compressor 1061, and the compressor 1061 pressurizes LOx in the oxidizer supply line 1091 and sends it under pressure to the injector 1002.

[0198] More specifically, the fuel supply line 1090 includes, in order from the upstream side with respect to the flow direction of LH, a compressor 1051 of a fuel turbo pump 1050, a main fuel valve 1093, and a mixer 1070. The oxidizer supply line 1091 includes, in order from the upstream side with respect to the flow direction of LOx, a compressor 1061 of an oxidizer turbo pump 1060, and a main oxidizer valve 1094.

[0199] The coolant / turbopump driving medium supply line 1092 branches off from the fuel supply line 1090 downstream of the compressor 1051 and upstream of the main fuel valve 1093 with respect to the flow direction of LH in the fuel supply line 1090. The coolant / turbopump driving medium supply line 1092 includes, in this order from upstream with respect to the flow direction of LH in the fuel supply line 1090, a combustion chamber cooling valve 1092c, a cooling passage 1033, a thrust control valve 1095, a turbine 1052 of the fuel turbopump 1050, and a turbine 1062 of the oxidizer turbopump 1060. That is, the turbine 1052 of the fuel turbopump 1050 and the turbine 1062 of the oxidizer turbopump 1060 are arranged in series on the coolant / turbopump driving medium supply line 1092. The cooling medium / turbo pump driving medium supply line 1092 also has a cooling passage for cooling the nozzle 4 upstream of the portion connected to the inside of the nozzle 4 at the other end.

[0200] Furthermore, the coolant / turbo pump driving medium supply line 1092 includes a junction pipe 1096, a mixture ratio control pipe 1097, and a bypass pipe 1098. The junction pipe 1096 branches off from the main pipe of the coolant / turbo pump driving medium supply line 1092 downstream of the cooling passage 1033 and upstream of the thrust control valve 1095, and connects to the mixer 1070. The mixture ratio control pipe 1097 branches off from the main pipe of the coolant / turbo pump driving medium supply line 1092 upstream of the turbine 1062 of the oxidizer turbopump 1060 and downstream of the turbine 1052 of the fuel turbopump 1050, and connects to the downstream side of the turbine 1062, thereby bypassing the turbine 1062. The mixture ratio control pipe 1097 includes a mixture ratio control valve 1099. A bypass pipe 1098 branches off from the main pipe of the coolant / turbo pump driving medium supply line 1092 downstream of the branching point of the junction pipe 1096 and upstream of the thrust control valve 1095, and is connected to the downstream side of the turbine 1062 of the oxidizer turbo pump 1060, thereby bypassing the turbines 1052 and 1062. This bypass pipe 1098 is equipped with a waste valve 1098a.

[0201] The main fuel valve 1093 adjusts the supply of LH to the injector 1002 by opening and closing the fuel supply line 1090. The main oxidizer valve 1094 adjusts the supply of LOx to the injector 1002 by opening and closing the oxidizer supply line 1091. The combustion chamber cooling valve 1092c adjusts the circulation of LH and GH in the coolant / turbo pump driving medium supply line 1092 by opening and closing the coolant / turbo pump driving medium supply line 1092. The thrust control valve 1095 opens and closes the coolant / turbo pump driving medium supply line 1092 to control the amount of GH introduced as a driving medium into the turbine 1052, thereby controlling the rotation speed of the turbine 1052, and thereby controlling the pressurization of LH by the compressor 1051, thereby controlling the thrust of the entire first rocket engine 111. The mixture ratio control valve 1099 controls the amount of GH introduced as a driving medium into the turbine 1062 by opening and closing the mixture ratio control pipe 1097, thereby controlling the rotation speed of the turbine 1062, and thereby controlling the pressurization of LOx by the compressor 1061, thereby controlling the mixture ratio (LOx / GH) throughout the combustor 1001, i.e., the ratio of LOx to GH injected from the injector 1002. The waste valve 1098a is opened and closed in accordance with the bypass amount when GH vaporized by passing through the cooling passage 1033 bypasses the turbines 1052 and 1062.

[0202] The mixer 1070 mixes the cryogenic LH that has passed through the main fuel valve 1093 with the high-temperature GH that has vaporized after passing through the cooling passage 1033, and supplies the mixed gas as GH to the combustor 1001. Note that the hydrogen used as fuel may exist in a gas-liquid two-phase state of GH and LH downstream of the cooling passage 1033 in the cooling medium / turbo pump driving medium supply line 1092.

[0203] In the first rocket engine 111 configured as described above, LH supplied via a fuel supply line 1090 is pumped to the combustor 1001 by the fuel turbopump 1050, and LOx supplied via an oxidizer supply line 1091 is pumped to the combustor 1001 by the oxidizer turbopump 1060, and the LOx and GH are mixed in the combustion chamber 1003 of the combustor 1001 and ignited by the igniter 1080 to burn the mixture, thereby generating thrust. Meanwhile, the coolant / turbopump driving medium supply line 1092 introduces a portion of the LH pumped by the fuel turbopump 1050 into a cooling passage 1033 provided in the wall of the combustion chamber 1003 of the combustor 1001, and the low-temperature LH cools the combustion chamber 1003. At this time, the LH2 that has gained energy by cooling the combustion chamber 1003 rises in temperature and is gasified to become GH2, a portion of which is introduced into the mixer 1070 via the junction pipe 1096 and mixed with the LH2 in this mixer 1070. The remaining GH2 is then introduced into the turbine 1052 of the fuel turbopump 1050 and the turbine 1062 of the oxidizer turbopump 1060 in that order, and acts as a driving medium for the turbines 1052 and 1062, and its expansion energy drives the turbines 1052 and 1062 to pressurize and deliver LH2 and LOx by the fuel turbopump 1050 and the oxidizer turbopump 1060, as described above. The GH2 that has driven the turbines 1052 and 1062 to rotation is then discharged into the nozzle 1004 from the other end of the coolant / turbopump driving medium supply line 92.

[0204] In this first rocket engine 111, the fuel turbopump 1050, which has a high density and therefore requires high output, is driven first by GH, followed by the oxidizer turbopump 1060. Furthermore, the pressure of GH after driving the fuel turbopump 1050 and the oxidizer turbopump 1060 is significantly lower than the initial pressure before the inlet of the turbine 1052, and therefore GH cannot be supplied into the combustion chamber 3, which has a pressure substantially equal to the pressure before the inlet of the turbine 1052, and is therefore discharged into the nozzle 1004, which is a low-pressure portion of the combustor 1001.

[0205] 11 to 22 are diagrams showing some of the components that make up the first rocket engine 111. FIG. 11 is an exploded perspective view of the injector (injector 1002). FIG. 12 is a perspective view showing the appearance of the MFV upstream pipe. FIG. 13 is a perspective view showing the CCV inlet pipe. FIG. 14 is a perspective view showing the appearance of the MFV case. FIG. 15 is a perspective view showing the appearance of the CCV case. FIG. 16 is a perspective view showing the appearance of the TVC case. FIG. 17 is a perspective view showing the TCV inlet pipe. FIG. 18 is a perspective view showing the UMCC outlet pipe. FIG. 19 is a perspective view showing the mixer piping. FIG. 20 is a perspective view showing the appearance of the MOV case. FIG. 21 is a perspective view showing the appearance of the MOV upstream pipe. FIG. 22 is a perspective view showing the appearance of the FTP turbine inlet pipe.

[0206] The injector shown in FIG. 11 corresponds to the injector 1002 in FIG. 10. The MFV upstream pipe shown in FIG. 12 corresponds to the piping indicated by arrow A in FIG. 10. The CCV inlet pipe shown in FIG. 13 corresponds to the piping indicated by arrow B in FIG. 10. The MFV case shown in FIG. 14 corresponds to the main fuel valve 1093 in FIG. 10. The CCV case shown in FIG. 15 corresponds to the combustion chamber cooling valve 1092c in FIG. 10. The TVC case shown in FIG. 16 corresponds to the thrust control valve 1095 in FIG. 10. The TCV inlet pipe shown in FIG. 17 corresponds to the piping indicated by arrow C in FIG. 10. The UMCC outlet pipe shown in FIG. 18 corresponds to the piping indicated by arrow D in FIG. 10. The mixer pipe shown in FIG. 19 corresponds to the piping indicated by arrow E in FIG. 10. The MOV case shown in FIG. 20 corresponds to the main oxidizer valve 1094 in FIG. 10. The MOV upstream pipe shown in FIG. 21 corresponds to the piping indicated by arrow F in FIG. 10.

[0207] 11 to 22, the portions indicated by the arrows in the figures are parts additively manufactured using a metal 3D printer. The metal 3D printer can be the same as that used to create the housing 2 of the fuel cell 1 described above. Each of the parts shown in FIGS. 11 to 22 is made of the same material as the housing 2 of the fuel cell 1 described above, and includes beryllium and / or a beryllium alloy, and further includes one or more of a high-entropy alloy having three or more elements, and a composite material having ceramic and aluminum, where the high-entropy alloy is made of an alloy in which the atomic ratio of each of the three or more elements is 50% or less.

[0208] As described above, because a portion of the first rocket engine 111 contains beryllium and / or a beryllium alloy, it is possible to achieve the same effects as the fuel cell 1 described above, and a lightweight, durable first rocket engine 111 can be constructed. The lightweight, durable first rocket engine 111 can be used in outer space. In particular, the component indicated by the arrow in the injector shown in FIG. 11 includes a disk member having multiple through-holes and multiple cylindrical bodies erected on the disk member and communicating with the multiple through-holes. Thus, the injector is composed of multiple parts. Therefore, by applying 3D printing technology to the manufacture of this component, the disk member and the multiple cylindrical bodies can be integrated into a single part through additive manufacturing. This reduces the manufacturing cost and time of the injector, improves part precision, and reduces its weight.

[0209] 23 is a perspective view showing a schematic configuration of the first liquid hydrogen tank 112. The first liquid hydrogen tank 112 is configured to include a cylindrical cylinder portion 2001 and dome portions 2002 and 2003.

[0210] The cylinder section 2001 is formed into a cylindrical shape by welding curved rib-integrated panels called isogrids in the axial direction. The dome sections 2002 and 2003 are formed in a dome shape. The dome sections 2002 and 2003 are welded to both ends of the cylinder section 2001. As a result, both ends of the cylinder section 2001 are closed by the dome sections 2002 and 2003.

[0211] The cylinder portion 2001 and / or the dome portions 2002, 2003 are parts that are additively manufactured using a metal 3D printer. The metal 3D printer may be the same as that used to create the housing 2 of the fuel cell 1 described above. The cylinder portion 2001 and / or the dome portions 2002, 2003 are made of the same material as the housing 2 of the fuel cell 1 described above, and include beryllium and / or a beryllium alloy, and further include one or more of a high-entropy alloy having three or more elements and a composite material having ceramic and aluminum, where the high-entropy alloy is made of an alloy in which the atomic ratio of each of the three or more elements is 50% or less.

[0212] As described above, the components constituting the first liquid hydrogen tank 112 contain beryllium and / or a beryllium alloy, which enables the same effects as those of the fuel cell 1 described above to be achieved, thereby enabling the construction of a lightweight, highly durable first liquid hydrogen tank 112. A lightweight, highly durable first liquid hydrogen tank 112 can be used in outer space. While the first liquid hydrogen tank 112 shown in FIG. 23 has the dome sections 2002 and 2003 welded to both ends of the cylinder section 2001, the cylinder section 2001 and the dome sections 2002 and 2003 may be integrally additively manufactured using a metal 3D printer. Specifically, the first liquid hydrogen tank 112 is manufactured by forming the dome section 2002 using a metal 3D printer, followed by the cylinder section 2001, and then the dome section 2003. This eliminates any seams between the cylinder section 2001 and the dome sections 2002 and 2003, thereby improving the strength of the first liquid hydrogen tank 112.

[0213] <Second-stage liquid-fuel rocket 120> Figure 25 is a diagram showing a schematic configuration of the second-stage liquid-fuel rocket 120. In addition to a second rocket engine 121, a second liquid oxygen tank 122, and a second liquid hydrogen tank 123, the second-stage liquid-fuel rocket 120 has a support section 124 that supports the second liquid oxygen tank 122 and the second liquid hydrogen tank 123 in a vertically aligned arrangement.

[0214] The support part 124 is configured in a cylindrical shape by assembling multiple frameworks into a truss structure. The second liquid oxygen tank 122 is fixed to one opening of the support part 124, and the second liquid oxygen tank 123 is fixed to the other opening. In this way,

[0215] The second liquid oxygen tank 122 and the second liquid hydrogen tank 123 are each composed of a cylinder portion and a dome portion, similar to the first liquid hydrogen tank 112. The second liquid oxygen tank 122 and the second liquid hydrogen tank 123 may be constructed by welding together a cylinder portion and a dome portion that have been additively manufactured using a metal 3D printer, or the cylinder portion and the dome portion may be integrally constructed using a metal 3D printer.

[0216] The support section 124 is formed by additively manufacturing multiple frameworks using a metal 3D printer, so there are no joints between the frameworks of the truss structure, and the support section 124 has high strength.

[0217] [Other Application Examples] In the above-described embodiment, an example has been described in which the components of the first rocket engine 111 contain beryllium and / or beryllium alloy, but the components of the second rocket engine 121 may contain beryllium and / or beryllium alloy. Also, in the above-described embodiment, an example has been described in which the components of the first liquid hydrogen tank 112 contain beryllium and / or beryllium alloy, but the first liquid oxygen tank 113, the second liquid oxygen tank 122, and the second liquid hydrogen tank 123 may contain beryllium and / or beryllium alloy.

[0218] The rocket nozzle (nozzle 1004 in FIG. 10 ) of the first rocket engine 111 may be made of a material containing beryllium and / or a beryllium alloy and may be formed by a metal 3D printer. Also, the turbine blades of the turbines (turbines 1052, 1062 in FIG. 10 ) of the first rocket engine 111 may be made of a material containing beryllium and / or a beryllium alloy and may be formed by a metal 3D printer.

[0219] Furthermore, an attitude control thruster (see Figures 24A and 24B) that controls the attitude of a device placed in space may be made of a material containing beryllium and / or a beryllium alloy and formed by a metal 3D printer.

[0220] Fig. 24A is a diagram showing the arrangement of attitude control thrusters in a supply vehicle that stores supplies to be supplied to the space station. Fig. 24B is a diagram showing the arrangement of attitude control thrusters in a capsule that is installed in the supply vehicle shown in Fig. 24A and stores supplies from the space station. The supply vehicle and capsule shown in Fig. 24A and Fig. 24B are made of a material containing beryllium and / or a beryllium alloy and are equipped with attitude control thrusters that use parts additively manufactured by a metal 3D printer.

[0221] The supply vehicle shown in Figure 24A is mounted on a rocket such as that shown in Figure 1 and placed in space by the rocket's launch. Once in space, the supply vehicle approaches the space station and is moored there by driving and controlling its attitude control thrusters. Space station workers remove supplies from the supply vehicle moored to the space station and store the supplies in the capsule shown in Figure 24B. After the supplies are stored in the capsule, the supply vehicle departs from the space station and releases the capsule before re-entering the atmosphere. After releasing the capsule, the supply vehicle re-enters the atmosphere and burns up. After re-entering the atmosphere, the capsule is guided and controlled to fall near the recovery site.

[0222] 24A and 24B are equipped with attitude control thrusters made of materials containing beryllium and / or beryllium alloys, making it possible to reduce the weight of the supply vehicle carrying the capsule. Moreover, since the attitude control thrusters burn out when the capsule re-enters the atmosphere, the weight of the returning capsule can be reduced. The supply vehicle is an example of an artificial celestial body in the present invention.

[0223] Other examples of artificial celestial bodies in the present invention include artificial satellites that orbit the Earth and probes that travel through space toward celestial bodies other than the Earth, such as the Moon, Mars, and asteroids, and explore these celestial bodies. Some artificial satellites and probes are equipped with attitude control thrusters. The attitude control thrusters of the artificial satellites and probes may also be produced by additive manufacturing using a metal 3D printer using a material containing beryllium and / or a beryllium alloy. Furthermore, at least some of the components of the artificial satellites and probes other than the attitude control thrusters may also be produced by additive manufacturing using a metal 3D printer using a material containing beryllium and / or a beryllium alloy.

[0224] Specifically, in addition to thrusters, satellites and probes are equipped with components such as batteries, solar cell arrays, power supply controllers, Earth sensors, reaction wheels, GPS receivers, fuel tanks, communication devices, and computers, and these components may include parts made by additive manufacturing using a metal 3D printer with materials containing beryllium and / or beryllium alloys. This allows for the weight of rockets carrying satellites and probes to be reduced.

[0225] <Specific examples of artificial satellites> Specific examples of artificial satellites include the following six types: (1) Communications satellites Function: Relays communications between remote locations on Earth, supporting telephone, television broadcasting, internet communications, etc. (2) Meteorological satellites Function: Conducts meteorological observations of the Earth, monitoring cloud movements, typhoons, precipitation, temperature, etc. (3) Earth observation satellites Function: Observes the state of the Earth's surface, oceans, and atmosphere, and is used for environmental monitoring, disaster prevention, resource exploration, etc. (4) Military satellites (reconnaissance satellites) Function: Monitors the Earth and collects information for military purposes, and is used for reconnaissance, communications, missile warning, etc. (5) Scientific satellites (astronomy and space exploration satellites) Function: Conducts scientific observations in outer space, and explores planets and asteroids in the solar system. (6) Positioning satellites (GPS satellites) Function: Builds the Global Positioning System (GPS) and other positioning systems, and provides location information.

[0226] <Satellite components and materials used> There are six types of components for satellites. Since beryllium and / or beryllium alloys are commonly used as materials, materials other than beryllium and / or beryllium alloys are also listed below. (1) Structural system (frames and panels) Role: Ensures the strength of the entire satellite and is the framework on which the equipment is mounted. Materials used: Aluminum alloy (lightweight and high strength) Titanium alloy (excellent heat and corrosion resistance) CFRP (carbon fiber reinforced plastic: lightweight and highly rigid) (2) Power supply system (solar cells and batteries) Role: Supplies power to the satellite. Materials used: Solar cells: GaAs (gallium arsenide), Si (silicon) Batteries: Lithium-ion batteries (high energy density) (3) Communications system (antennas and transceivers) Role: Communicates with the ground. Materials used: Antennas: aluminum, CFRP Transceivers: GaAs semiconductors, silicon (4) Propulsion system (engines and thrusters) Role: Corrects orbit and controls attitude. Materials used: ・Propellant: hydrazine (liquid), xenon (electric propulsion) ・Thruster body: Ni (nickel), molybdenum, titanium (5) Thermal control system (radiator / insulation material) Role: Maintains the temperature of the satellite at an appropriate level. Materials used: ・Insulation material: multi-layer insulation (MLI), Kapton ・Heat sink: aluminum, SiC (silicon carbide) (6) Attitude control system (gyro / reaction wheel) Role: Controls the orientation of the satellite and stabilizes the observation equipment. Materials used: ・Gyro: silicon MEMS, aluminum ・Wheel: CFRP, titanium

[0227] <Specific examples of probes> Specific examples of probes include the following six types. (1) Flyby Probe Function: - Makes observations while passing near planets or asteroids. - Changes orbit by utilizing the gravity of the probe's target (swing-by). Representative examples: - Voyager 1 and 2 (NASA, launched in 1977) - New Horizons (NASA, launched in 2006) (2) Orbiter Function: - Makes long-term observations while orbiting a planet or moon. - Records detailed changes in the atmosphere and surface. Representative examples: ・Himawari (JAXA, Japan's geostationary meteorological satellite) ・Mars probe "Mars Reconnaissance Orbiter" (NASA, launched in 2005) ・Jupiter probe "Juno" (NASA, launched in 2011) (3) Lander Function: ・Lands on the surface of the exploration target to conduct geological surveys and environmental measurements. ・Conducts scientific observations using seismometers and thermometers. Representative examples: ・Mars probe "Insight" (NASA, landed in 2018) ・Minerva-II, the lander of the asteroid probe "Hayabusa2" (JAXA, landed on the asteroid Ryugu in 2018) (4) Rover Function: ・Conducts detailed exploration while moving over the surface of a planet or the moon. ・Collects and analyzes surface samples. Representative examples: ・Mars rover "Curiosity" (NASA, arrived on Mars in 2012) ・Mars rover "Perseverance" (NASA, arrived on Mars in 2021) (5) Sample Return Mission Function: ・Collect samples from the probe and bring them back to Earth. Representative examples: ・Asteroid probe "Hayabusa" (JAXA, returned to Earth in 2010) ・Asteroid probe "Hayabusa 2" (JAXA, successfully brought back samples in 2020) ・Martian moon probe "MMX" (JAXA, scheduled for 2024) (6) Manned Spacecraft Function: ・Astronauts board and carry out activities in space. Representative examples: ・International Space Station (ISS) ・Apollo program (NASA) ・Manned lunar exploration "Artemis program" (NASA)

[0228] <Probe components and materials used> The components of a space probe are classified into the following six systems. Note that beryllium and / or beryllium alloys are commonly used as materials, so we will list materials other than beryllium and / or beryllium alloys. (1) Structural system (frames and panels) Role: Ensures the strength of the entire probe and carries various equipment. Materials used: Aluminum alloy (lightweight and strong) Titanium alloy (excellent heat and corrosion resistance) CFRP (carbon fiber reinforced plastic, lightweight and rigid) (2) Power supply system (solar cells and batteries) Role: Supplies power to the space probe. Materials used: Solar cells: GaAs (gallium arsenide), Si (silicon) Batteries: Lithium-ion batteries (3) Communications system (antennas and transceivers) Role: Communicates with Earth. Materials used: Antennas: aluminum, CFRP Transceivers: GaAs semiconductors, silicon (4) Propulsion system (engines and thrusters) Role: Performs orbital correction and attitude control. Materials used: ・Propellant: hydrazine (liquid), xenon (electric propulsion) ・Thruster body: nickel, molybdenum, titanium (5) Thermal control system (radiator, heat insulator) Role: Maintains the temperature of the probe at an appropriate level. Materials used: ・Insulator: MLI (multi-layer insulation), Kapton ・Heat sink: aluminum, silicon carbide (SiC) (6) Scientific observation equipment (camera, spectrometer, sample collection device) Role: Carries out observations and sample collection. Materials used: ・Camera: silicon CMOS sensor, quartz lens ・Spectrometer: optical glass, aluminum mirror ・Sample collection device: titanium, carbon fiber

[0229] In addition, the probe may be equipped with a landing mechanism, which is the probe's legs, and this landing mechanism may include parts made by additive manufacturing using a metal 3D printer with a material containing beryllium and / or a beryllium alloy.

[0230] Furthermore, according to the specific example described above, a rover is included as an example of a probe. The rover is stored in the probe and moves from the landed probe to the ground of another celestial body. The rover has functions such as taking photographs while traveling on the ground of the celestial body, transmitting the photographic data, and retrieving samples from the ground and returning to the probe. Parts that perform such functions on the rover may also include parts made by additive manufacturing using a metal 3D printer with a material containing beryllium and / or a beryllium alloy. This allows for the weight of the rocket carrying the probe in which the exploration vehicle is stored.

[0231] While supply vehicles, satellites, and probes have been cited as specific examples of artificial celestial bodies in this embodiment, space stations are also included. In essence, any artificial structure placed in outer space or on a celestial body other than Earth is included in the artificial celestial body of the present invention. For example, the present invention can be applied to building materials for structures other than probes, such as lunar bases, if there are plans to build such structures on celestial bodies other than Earth in the future. It can also be applied to components constituting solar-powered regenerative fuel cell systems that supply power to such structures, as well as components and parts of various devices and furnaces that generate and supply energy. At least some of these devices and parts may include parts made by additive manufacturing using a metal 3D printer with a material containing beryllium and / or a beryllium alloy.

[0232] <Other Application Examples> Although the present embodiment has been described above, the present embodiment is not limited to being applied to the above-mentioned devices and components. More specifically, the present embodiment can be applied to the following devices and components.・Parts that make up solid motors that provide thrust to rockets, for example, motor cases and insulation ・Large parts that make up the main body of a rocket, for example, frames and panels ・Components for satellites and probes, for example, solar cell paddles, star trackers, reaction wheels and high-performance actuators ・Parts that make up altimeter lidars that are mounted on satellites and that shine a laser at the Earth's surface and precisely measure the altitude of the Earth's surface or an object based on the time difference of the reflected light ・Parts that make up optical sensors that are mounted on satellites and used to collect 3D topographical information ・Parts that make up devices mounted on satellites that orbit the Moon, for example, devices that generate terahertz waves to estimate promising locations on the moon's surface where resources such as water are located, and devices that perform lunar positioning ・Parts that make up semi-permanent power sources that use americium and can be used for long periods of time, which are used for lunar surface development, Mars exploration, and exploration beyond the Martian sphere, etc. ・Parts that make up deployable aeroshells for landing on celestial bodies with an atmosphere, such as Mars - Modules that are attached to the space station and form spaces where astronauts can work without space suits (for example, the Japanese Experiment Module "Kibo"), and parts that make up the experimental equipment placed within the modules

[0233] Next, examples of beryllium and / or beryllium alloys that can be used in this embodiment will be described.

[0234] [Example 1] Figures 26 to 28 show experimental results of the density and tensile strength of the material system of Example 1 and the comparative material. The material system of Example 1 shows Be (beryllium) and elements alloyed with Be. Furthermore, all of Example 1 was additively manufactured using a metal 3D printer. As a result, the Be alloy contains not only Be but also compounds of Be and alloying elements. The results are shown in the material type column as the Be compounds contained in Be. The metal 3D printers used were the Directed Energy Deposition (DED) method and the Powder Fabrication method (electron beam). The DED method involved introducing various element powders into a laser probe and using a laser to laminate the alloy. The Powder Fabrication method also involved using a powder bed method to directly melt the alloy powder with an electron beam and laminate it into a specific shape. The metal structure of the formed molding material differs between the DED method and the powder shaping method. In addition to a metal crystalline structure, amorphous structures and metallic glass structures were also observed in the DED method. However, the material of Example 1 can be applied as a material of the present invention. In the powder shaping method, the metal structure is mainly composed of crystals, and the material of Example 1 can be applied as a material of the present invention. All of the materials of Example 1 were made of the specified Be alloy shown in the material system and material type columns, and by additive manufacturing using a metal 3D printer, they were lower in density and lighter in weight than the comparative materials Ti and 64Ti. Furthermore, the tensile strength was also higher than that of the comparative materials, and the material properties of the material of Example 1 surpassed those of the comparative materials.

[0235] Example 2 FIG. 29 is a diagram showing the experimental results of the density and tensile strength of the material system of Example 2 and the comparative material.

[0236] The material of Example 2 consisted of Be (beryllium) and elements alloyed with Be, with the molar ratio of elements other than Be being 50 at% (atomic percent) or less. All materials in Example 2 were additively manufactured using a metal 3D printer. Directed Energy Deposition (DED) and powder sintering (electron beam) were used as the metal 3D printers. The DED method involved introducing various element powders into a laser probe and using a laser to create an alloy layer. The powder sintering method involved directly melting the alloy powder with an electron beam using a powder bed method and layering it into a specific shape. The metal structure of the resulting sintered material differed between the DED and powder sintering methods. In the DED method, amorphous and metallic glass structures were observed in addition to a metallic crystalline structure, but this is still applicable to the material of the present invention. The powder sintering method primarily produced a metallic structure composed of crystals, making it applicable to the material of the present invention. Any of the materials of Example 2 was additively manufactured using a metal 3D printer, and the density was 1.846 g / cm of Be. ３ The alloy was lighter than the conventional alloy Nos. 1 to 12. Furthermore, the tensile strength exceeded the 980 MPa of the previously used 64Ti (Ti-6 wt% Al-4 wt% V), making it possible to invent an ultra-lightweight, high-strength alloy. These alloys are not limited to the alloys shown in Nos. 1 to 12. New alloys exhibiting similar excellent properties could be obtained by alloying Be with at least two elements selected from Li, Na, Mg, K, Ca, and Rb.

[0237] Example 3 FIG. 30 is a diagram showing the experimental results of the density and tensile strength of the material system of Example 3 and the comparative material.

[0238] In Figure 30, the material of Example 3 is shown in the column of material type, and the composition of the material of Example 3 is shown as the molar ratio of each element. All alloys were additively manufactured using a metal 3D printer. As a result, all of the Be alloys in the material of Example 3 had a density of 4.508 g / cm3, which is the same as that of Ti. ３While achieving the following lightness, the strength also exceeded the 980 MPa of Ti and 64Ti (Ti-6Al-4V (wt%)). The metal 3D printers used were the Directed Energy Deposition (DED) method and the powder shaping method (electron beam). In the DED method, various element powders were introduced into a laser probe and a laser was used to laminate the alloy. In the powder shaping method, the alloy powder was directly melted with an electron beam using a powder bed method and laminated into a specific shape. The metal structure of the formed shaping material differed between the DED method and the powder shaping method. In addition to a metal crystalline structure, amorphous and metallic glass structures were also observed in the DED method, but this is applicable to the material of the present invention. In the powder shaping method, the metal structure is mainly composed of crystals, making it applicable to the material of the present invention.

[0239] Furthermore, the composition of each alloy is not limited to the molar ratios of Nos. 1 to 27, and similar favorable low density and high tensile strength can be obtained even when the chemical composition of elements other than Be is 5 to 35 at% per element. Therefore, Be alloys having these chemical compositions are also materials of the present invention.

[0240] Example 4 FIGS. 31 to 34 are diagrams showing experimental results of the density and tensile strength of the material system of Example 4 and the comparative material.

[0241] In Figures 31 to 34, the materials of Example 4 are listed in the material type column. The composition of the materials in Example 4 is shown as the molar ratio of each element. All alloys were additively manufactured using a metal 3D printer. As a result, all Be alloys of the present invention achieved a light weight with a density of 8.933 g / cm3 or less, which is the same as Cu, while also exceeding the 980 MPa of Ti and 64Ti (Ti-6Al-4V (wt%)). Directed Energy Deposition (DED) and powder shaping (electron beam) methods were used as the metal 3D printers. In the DED method, various element powders were introduced into a laser probe, and a laser was used to stack the alloy. In addition, in the powder shaping method, a powder bed method was used, in which alloy powder was directly melted with an electron beam and stacked into a specific shape. The metal structure of the formed shaping material differs between the DED method and the powder shaping method, and in addition to the metal crystalline structure, amorphous structure and metallic glass structure were also observed in the DED method, but this can be applied to the material of the present invention. In the powder shaping method, the metal structure mainly consists of crystals, and this can be applied to the material of the present invention.

[0242] Furthermore, the composition of each alloy is not limited to the molar ratios of Nos. 1 to 124, and even if the chemical composition of elements other than Be is 5 to 35 at% per element, a density equal to or lower than that of Cu and high tensile strength can be obtained. Therefore, Be alloys having these chemical compositions can also be used as materials in the present invention.

[0243] [Example 5] Fig. 35 is a diagram showing the experimental results of the density and tensile strength of the material system of Example 5 and the comparative material.

[0244] In Figure 35, the materials of Example 5 are shown in the column for material type. The composition of the materials of Example 5 is shown as the molar ratio of each element. All alloys were additively manufactured using a metal 3D printer. As a result, all of the Be alloys of Example 5 had a density of 8.933 g / cm3, which is the same as that of Cu. ３While achieving the following lightness, the high-temperature strength at 850°C exceeded 290 MPa, which is comparable to that of Inconel 625 and Inconel 718. The metal 3D printers used were the Directed Energy Deposition (DED) method and the powder sintering method (electron beam). In the DED method, various element powders were introduced into a laser probe and a laser was used to laminate the alloy. In the powder sintering method, the alloy powder was directly melted with an electron beam using a powder bed method and laminated into a specific shape. The metal structure of the resulting sintering material differed between the DED method and the powder sintering method. In the DED method, in addition to a metal crystalline structure, amorphous and metallic glass structures were also observed, which can be applied to the material of the present invention. In the powder sintering method, the metal structure is primarily composed of crystals, making it applicable to the material of the present invention.

[0245] Furthermore, the composition of each alloy is not limited to the molar ratios of Nos. 1 to 12. Even if the chemical composition of elements other than Be is 1 to 35 at% per element, a density equal to or lower than that of Cu and high-temperature tensile strength can be obtained. Therefore, Be alloys having these chemical compositions can also be used as materials in the present invention.

[0246] [Example 6] Figure 36 is a conceptual diagram showing an example of a manufacturing process for a rocket part made of an alloy structure.

[0247] The alloy structure is obtained by repeatedly performing the additive manufacturing steps shown in Figure 36 (a) to (g) in order to three-dimensionally model the alloy structure. The additive manufacturing step can be performed using a conventional powder additive manufacturing device for metals, and the alloy powder prepared in the powder preparation step is used as the raw material powder for such an additive manufacturing step. The heating means provided in the additive manufacturing device may be one based on an appropriate heating principle, such as electron beam heating, laser heating, microwave heating, plasma heating, focused light heating, or high-frequency heating. Among these, additive manufacturing devices using electron beam heating or laser heating are particularly suitable. This is because electron beam heating or laser heating allows for relatively easy control of the heat source output, miniaturization of the heated area of ​​the alloy powder, and the modeling accuracy of the alloy structure.

[0248] The additive manufacturing process, in detail, includes a powder spreading process and a solidified layer manufacturing process. In the additive manufacturing process, a layered solidified structure (solidified layer) is formed through the steps shown in order from (a) to (g) in Figure 36, and by repeating the formation of the layered solidified structure (solidified layer), an alloy structure consisting of an assembly of solidified structures is manufactured.

[0249] 36(a), the additive manufacturing apparatus is provided with a piston that can be raised and lowered and has a substrate mounting table 3001 at its upper end. A processing table 3002 that is not linked to the piston is provided around the substrate mounting table 3001, and is also provided with a powder feeder (not shown) that supplies raw material powder 3010 onto the processing table 3002, a recoater 3003 that spreads the supplied raw material powder 3010, heating means 3004 that heats the raw material powder 3010, an air blast (not shown) that removes the raw material powder 3010 from the processing table 3002, a temperature controller (not shown), etc. The processing table 3002 and these devices are housed in a chamber, and the atmosphere inside the chamber is a vacuum atmosphere or an inert gas atmosphere such as argon gas depending on the type of heating means 3004, and the atmospheric pressure and temperature are controlled. When performing additive manufacturing, the substrate 3015 is placed on the substrate mounting table 3001 in advance, and the substrate 3015 is aligned so that the surface to be manufactured (top surface) and the top surface of the processing table 3002 are flush with each other.

[0250] Any suitable material can be used as the substrate 3015 as long as it has heat resistance to heating by the heating means 3004. In this method for manufacturing an alloy structure, additive manufacturing of the alloy structure is performed on the surface to be molded of the substrate 3015, thereby obtaining a molded object in which the substrate 3015 and the alloy structure are integrated. Therefore, the substrate 3015 can be a substrate 3015 of an appropriate shape, such as a flat plate, assuming that it will be separated from the alloy structure by cutting or the like. Alternatively, a structural member, mechanical member, or the like of any shape having a surface to be molded can be used as the substrate 3015, assuming that the substrate 3015 and the alloy structure will function in an integrated state.

[0251] In the powder spreading step, the prepared alloy powder 3010 is spread on the surface to be built. That is, in the first powder spreading step in additive manufacturing, the alloy powder 3010 is spread on a substrate 3015 placed on an additive manufacturing apparatus. As shown in FIG. 36( b), the alloy powder 3010 (see FIG. 36( a)) supplied onto a processing table 3002 by a powder feeder (not shown) is spread by sweeping a recoater 3003 over the surface to be built (substrate 3015) to spread the alloy powder 3010 in a thin layer. The thickness of the thin layer of alloy powder 3010 formed by spreading can be adjusted as appropriate depending on the output of the heating means for melting the alloy powder 3010, the average particle diameter of the alloy powder 3010, and the like, but is preferably in the range of approximately 10 μm to 1000 μm.

[0252] In the solidified layer fabrication process, the spread alloy powder 3010 is locally heated to melt it and then solidify it. The area heated by the local heating is scanned across the plane on which the alloy powder 3010 is spread, thereby forming a solidified layer 3040. The solidified layer 3040 (see FIG. 36( e) ), which will be described later, is formed by scanning the area heated by the heating means 3004 in accordance with two-dimensional shape information obtained from three-dimensional shape information (e.g., 3D-CAD data) representing the three-dimensional shape of the alloy structure to be manufactured. The two-dimensional shape information is information that specifies the shape of each thin layer when the three-dimensional shape of the alloy structure to be manufactured is virtually sliced ​​at predetermined thickness intervals and divided into a set of multiple thin layers. The solidified layer 3040 having a predetermined two-dimensional shape and thickness is formed in accordance with this two-dimensional shape information.

[0253] As shown in Figure 36(c), localized heating of the alloy powder 3010 is performed by using a heating means 3004 to limit the heated area on the spread alloy powder 3010, and selectively melting a portion of the spread alloy powder 3010 to form a tiny molten pool (molten zone 3005). The size of the molten zone 3005 formed by melting the alloy powder 3010 is preferably 1 mm or less in diameter. Limiting the molten zone 3005 to such a small size improves the molding accuracy of the alloy structure and the uniformity of the elemental composition in the solidified structure.

[0254] The heated region caused by localized heating of the alloy powder 3010 is scanned so as to move parallel to the surface to be built, as shown in FIG. 36(d). Scanning of the heated region can be performed by scanning the main body of the heating means 3004, or by scanning the irradiation spot of the heat source using a galvanometer mirror or the like, or by any other suitable method such as raster scanning. In this case, overlapping scanning using multiple radiation sources may be performed to flatten the irradiated energy density. Then, by scanning the heated region, new local heating is performed in the region where the alloy powder 3010 has not yet melted, and heating of the region where the alloy powder 3010 has already melted and formed the molten portion 3005 is stopped, and the molten portion 3005 is cooled and solidified at ambient temperature. The solidified portion 3020 formed by solidification of the molten portion 3005 forms a dense aggregate of solidified portions 3020 while integrating with the substrate and the previously formed solidified portions 3020.

[0255] The scanning speed, output, energy density, and scanning width of the heating means 3004 may be adjusted as appropriate based on the elemental composition and particle size distribution of the alloy powder 3010, the material of the substrate 3015, the positional relationship between the molten portion 3005 and the solidified portion 3020, the thermal conduction and thermal radiation estimated from the chamber temperature, etc. The cooling temperature for cooling the molten portion 3005 may be set taking into consideration dimensional changes, thermal distortion, etc., depending on the elemental composition of the alloy structure. By performing scanning while maintaining the size, melting speed, cooling speed, and time interval between melting and cooling of the molten portion 3005 within predetermined ranges, it is possible to homogenize the strength distribution of the resulting alloy structure and reduce residual stress and surface roughness.

[0256] 36( c) to 36(e), a solidified layer 3040 having a predetermined two-dimensional shape and thickness is formed on a substrate 3015 placed on a substrate mounting table 3001 by repeatedly melting and solidifying the alloy powder 3010 to form a collection of solidified portions 3020. After the unmelted alloy powder 3010 remaining around and on the upper surface of the formed solidified layer 3040 is removed by air blasting, as shown in FIG. 36(f), the substrate mounting table 3001 is lowered by a height corresponding to the thickness of the formed solidified layer 3040, and the new surface to be formed on the upper surface of the solidified layer 3040 is aligned so as to be flush with the upper surface of the processing table 3002.

[0257] After alignment, the powder spreading process is performed as shown in Figures 36(a) and 36(b), and the newly supplied alloy powder 3010 is spread on the upper surface of the already formed solidified layer 3040, as shown in Figure 36(g). Thereafter, the solidified layer shaping process is performed as shown in Figures 36(c) to 36(e), and the next solidified layer 3040 is stacked. The stacked solidified portion 3020 is integrated with a part of the underlying solidified layer 3040 and sintered densely. Thereafter, by repeating the powder spreading process and the solidified layer shaping process in the same manner, with the upper surface of the formed solidified layer 3040 as the target surface, an alloy structure of the desired shape and dimensions can be additively manufactured.

[0258] In the solidified layer shaping process, after the alloy powder 3010 melts, the solidified portion 3020 and the solidified layer 3040 can be subjected to shape forming and surface processing at a high temperature before the solidified portion 3020 is formed. Such processing can be performed using, for example, a metal or alloy tool, or an inorganic or inorganic composite tool such as a diamond powder, an intermetallic compound powder, or a compacted powder of tungsten carbide, when the surface temperature of the molten portion 30 and the solidified portion 40 is about 500°C or higher, preferably in a temperature range of 50% to 75% of the melting point (Tm) of the alloy. This processing allows difficult-to-machine alloy structures to be shaped to higher-precision shapes and dimensions, or to be decorated.

[0259] The alloy structure additively manufactured by repeating the powder spreading process and the solidified layer shaping process may be subjected to a separate hot isostatic pressing (HIP) process, because the hot isostatic pressing of the alloy structure may make the solidification structure of the alloy structure denser or remove defects in the solidification structure.

[0260] By repeating this additive manufacturing process to perform three-dimensional fabrication, an alloy structure with columnar crystals as the main crystal can be manufactured with the desired shape and dimensions by assembling a fine solidification structure. Furthermore, the elemental composition of each of the fine solidification structures (solidified portion 3020) closely reflects the elemental composition of the alloy powder used, allowing for the formation of a solid solution phase with a highly uniform elemental composition distribution and a highly uniform mechanical strength distribution. Furthermore, by forming a solidification structure (solidified portion 3020) by heating from one direction, it is possible to stack solidification structures (solidified layers 3040) whose crystal growth direction is oriented in approximately one direction, allowing for the formation of a highly anisotropic alloy structure.

[0261] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. Furthermore, the effects described in the above-described embodiments are merely a list of the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the above-described embodiments. Furthermore, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those having all of the configurations described.

[0262] REFERENCE SIGNS LIST 1 fuel cell 2 housing 3 separator 4 cell 41 fuel flow path 42 fuel electrode 43 electrolyte 44 oxygen electrode 45 oxygen flow path A air supply section E exhaust section F fuel supply section 111 first rocket engine 112 first liquid hydrogen tank

Claims

1. A rocket engine part manufactured using a metal 3D printer, A beryllium alloy structure having a columnar crystal as its main crystal, containing beryllium and alloying elements. The aforementioned alloy structure has a density less than 8.933 g / cm³ and a tensile strength of 980 MPa or more, and is a component for a rocket engine.

2. The rocket engine component according to Claim 1, wherein the alloying element comprises one or more elements selected from B, Mg, Al, Fe, Ni, P, S, Ca, Sc, Ti, V, Cr, Mn, Co, Cu, Se, Sr, Y, Zr, Nb, Mo, Ag, In, Sn, Sb, Ba, Hf, Ta, W, Re, La, Nd, Sm, Gd, Yb, Th, Zn, Ga, Ge, and Zr.

3. The alloying element includes an element whose specific gravity as a pure element at a temperature of 25°C and a pressure of 1013 hPa is approximately the same as or less than the specific gravity of titanium. The rocket engine component according to claim 1, wherein the density of the alloy structure is less than 4.43 g / cm³ and the tensile strength is 980 MPa or more.

4. The rocket engine component according to claim 3, wherein the alloying element comprises one or more elements selected from B, Mg, Al, Fe, Ni, P, S, Ca, Sc, Ti, V, Cr, Mn, Co, Cu, Se, Sr, Y, Zr, Nb, Mo, Sb, Ba, Hf, Ta, W, Re, La, Nd, Sm, Gd, Yb, and Th.

5. The beryllium alloy structure is a high-entropy alloy having three or more elements, wherein the beryllium contains two or more elements selected from Li, Na, Mg, K, Ca, and Rb as the alloying elements. The atomic ratio of elements other than beryllium is 50% or less. The rocket engine component according to claim 1, wherein the density of the alloy structure is less than 1.846 g / cm³ and the tensile strength is 980 MPa or more.

6. A rocket engine component according to claim 1, which is manufactured by additive manufacturing using a metal 3D printer and powder bed fusion.

7. The rocket engine component according to any one of claims 1 to 6, wherein the rocket engine component is a component comprising one or more members selected from an oxidizer tank for storing liquid oxygen, an oxidizer turbopump, and an oxidizer supply line.

8. The rocket engine component includes a tank that contains liquid hydrogen inside, The rocket engine component according to any one of claims 1 to 6, wherein the tank has a cylindrical section and dome sections that close both ends of the cylinder section, and the cylinder section and the dome section are integrally layer-formed using a metal 3D printer.

9. A component for an artificial celestial body, which is mounted on a rocket and placed in outer space, and is manufactured using a metal 3D printer, is a component for an artificial celestial body that is created by additive manufacturing. A beryllium alloy structure having a columnar crystal as its main crystal, containing beryllium and alloying elements. The aforementioned alloy structure has a density less than 8.933 g / cm³ and a tensile strength of 980 MPa or more, and is a component for artificial celestial bodies.

10. The component for an artificial celestial body according to claim 9, comprising an engine that generates thrust for controlling the orbit and attitude of the artificial celestial body.

11. The artificial celestial body is an artificial satellite orbiting the Earth, as per claim 9 or 10.

12. The artificial celestial body is a probe that moves toward a predetermined celestial body other than Earth, as per claim 9 or 10.

13. A component for a probe, manufactured using a metal 3D printer, which is mounted on a probe that travels through space toward a predetermined celestial body other than Earth, and which has the function of traveling on the ground of the predetermined celestial body, collecting samples, and returning to the probe, and which constitutes at least a part of the probe vehicle, A beryllium alloy structure having a columnar crystal as its main crystal, containing beryllium and alloying elements. The aforementioned alloy structure has a density less than 8.933 g / cm³ and a tensile strength of 980 MPa or more, and is a component for an exploration vehicle.