CN116237521B - Preparation method of nuclear fuel element - Google Patents

Preparation method of nuclear fuel element Download PDF

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Publication number
CN116237521B
CN116237521B CN202211582284.0A CN202211582284A CN116237521B CN 116237521 B CN116237521 B CN 116237521B CN 202211582284 A CN202211582284 A CN 202211582284A CN 116237521 B CN116237521 B CN 116237521B
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tungsten
fuel
template
particles
printing
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CN116237521A (en
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仲亚娟
林俊
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Shanghai Institute of Applied Physics of CAS
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Shanghai Institute of Applied Physics of CAS
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/06—Metallic powder characterised by the shape of the particles
    • B22F1/065—Spherical particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/17—Metallic particles coated with metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/18—Non-metallic particles coated with metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/10—Formation of a green body
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/10—Formation of a green body
    • B22F10/12—Formation of a green body by photopolymerisation, e.g. stereolithography [SLA] or digital light processing [DLP]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/20—Direct sintering or melting
    • B22F10/28—Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/60—Treatment of workpieces or articles after build-up
    • B22F10/64—Treatment of workpieces or articles after build-up by thermal means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00—Processes of additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y40/00—Auxiliary operations or equipment, e.g. for material handling
    • B33Y40/20—Post-treatment, e.g. curing, coating or polishing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y70/00—Materials specially adapted for additive manufacturing
    • B33Y70/10—Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y80/00—Products made by additive manufacturing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

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  • Composite Materials (AREA)
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  • Nanotechnology (AREA)
  • Ceramic Engineering (AREA)
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  • Powder Metallurgy (AREA)

Abstract

The invention relates to a preparation method of a nuclear fuel element, which comprises the steps of printing a fuel-free shell through tungsten powder by adopting 3D printing equipment; printing a first tungsten template through tungsten powder, loading tungsten coated fuel particles on a fuel site groove, and filling gaps by using the tungsten powder; printing a second tungsten template through tungsten powder, mounting tungsten coated fuel particles on the second tungsten template, and filling gaps by using the tungsten powder; the corresponding operation of printing the second tungsten template is repeated until the design layer number requirement is reached; printing a third tungsten template serving as a sealing part through tungsten powder to obtain a preformed blank; and performing heat treatment on the preformed blank body to obtain the nuclear fuel element. According to the preparation method of the nuclear fuel element, the three-dimensional fuel-free shell and the prefabricated template with the point position grooves are manufactured through layer-by-layer stacking and forming of materials, and the reduction of the service life of the nuclear fuel element due to the fact that fuel particles are densely stacked to form local hot spots is avoided.

Description

Preparation method of nuclear fuel element
Technical Field
The present invention relates to nuclear reactors, and more particularly to a method of manufacturing a nuclear fuel element.
Background
The nuclear heat propulsion system provides power for the spacecraft outside the earth atmosphere, is a key technology for future space science research, and receives high attention from aerospace countries such as Meihrussia. Nuclear heat propulsion uses the heat of a reactor to heat a propellant such as liquid hydrogen, helium, etc. to an extremely high temperature, so that the propellant is converted into gas, and the gas is ejected through a nozzle, thereby generating power. The thrust generated by the system is 1 ten thousand times of that of an electric propeller, and the specific impulse is 2-5 times of that of a chemical rocket.
The nuclear fuel element is the core component of the reactor design. The design and fabrication of nuclear fuel elements determines the advancement and economics of the reactor. The design and preparation of the metal-based dispersion type fuel element based on the coated fuel particles are expected to meet the requirements of advanced nuclear heat propulsion on fuel.
The traditional fuel element preparation process has the problems of longer production period, higher cost, low raw material utilization rate and the like.
Disclosure of Invention
In order to solve the problems of long preparation period, high cost and the like of the nuclear fuel element in the prior art, the invention provides a preparation method of the nuclear fuel element.
The method for preparing the nuclear fuel element comprises the following steps: s1, printing a fuel-free shell through tungsten powder by adopting 3D printing equipment; s2, printing a first tungsten template with a fuel site groove on the top surface through tungsten powder, placing the first tungsten template in a fuel-free shell, loading tungsten coated fuel particles on the fuel site groove, and filling gaps by using the tungsten powder; s3, printing a second tungsten template with fuel site grooves on the bottom surface and the top surface through tungsten powder, placing the second tungsten template in a fuel-free shell, enabling the tops of tungsten coated fuel particles below to be contained in the fuel site grooves on the bottom surface of the second tungsten template, placing the tungsten coated fuel particles on the fuel site grooves on the top surface of the second tungsten template, and filling gaps by using tungsten powder; s4, repeating the step S3 for a plurality of times; s5, printing a third tungsten template with a fuel site groove on the bottom surface through tungsten powder as a sealing part, placing the third tungsten template in a fuel-free shell, and enabling the tops of tungsten coated fuel particles below to be contained in the fuel site groove on the bottom surface of the third tungsten template, so as to obtain a preformed blank; and S6, performing heat treatment on the preformed blank body to obtain the nuclear fuel element.
Preferably, the fuel-free housing is spherical, cylindrical, hexagonal prismatic, square or rectangular.
Preferably, the tungsten coated fuel particles are a fuel core and a tungsten layer in that order from the inside to the outside.
Preferably, the second tungsten template is buckled on the first tungsten template, and the third tungsten template is buckled on the second tungsten template.
Preferably, the first, second and third tungsten templates have a thickness of between 0.2 and 1.5 mm.
Preferably, the tungsten coated fuel particles are spherical and the fuel site slots are hemispherical slots, the diameter of the tungsten coated fuel particles being less than the diameter of the hemispherical slots. Preferably, the diameter of the tungsten coated fuel particles is 0.03-0.13mm smaller than the diameter of the hemispherical grooves. In a preferred embodiment, the diameter of the tungsten coated fuel particles is 0.08mm less than the diameter of the hemispherical grooves.
Preferably, the tungsten coated fuel particles have a diameter of between 0.5 and 1.02mm and the hemispherical grooves have a diameter of between 0.6 and 1.1 mm. In a preferred embodiment, the tungsten coated fuel particles have a diameter of 0.92mm and the hemispherical grooves have a diameter of 1mm.
Preferably, the spacing between adjacent tungsten coated fuel particles is between 0.1 and 0.3 mm. In a preferred embodiment, the spacing between adjacent tungsten coated fuel particles is 0.2mm.
Preferably, the tungsten coated fuel particles comprise between 11% and 60% of the total volume fraction of the nuclear fuel element. Preferably, the tungsten coated fuel particles comprise between 15% and 45% of the total volume fraction of the nuclear fuel element. In a preferred embodiment, the tungsten coated fuel particles comprise 24.8% by volume of the total nuclear fuel element.
Preferably, the heat treatment includes a sintering treatment and a densification treatment.
According to the preparation method of the nuclear fuel element, the nuclear fuel element is prepared by a 3D printing forming technology, and the three-dimensional fuel-free shell and the prefabricated template with the point position grooves are manufactured by layer-by-layer stacking forming of materials, so that uniform distribution of fuel particles is facilitated, and the reduction of the service life of the nuclear fuel element due to the fact that the fuel particles are stacked densely to form local hot spots is avoided. Different from the traditional material reduction manufacturing technology such as machining, the material reduction manufacturing technology is an additive manufacturing technology, and has the advantages of simple process, high forming speed, high raw material utilization rate and great reduction in the preparation cost of the nuclear fuel element. Thus, the nuclear fuel element is prepared by the additive manufacturing technology, and the specific fuel-free area and the specific fuel area can be realized as required, so that the ordered or random distribution of fuel particles is realized, the forming speed is improved, the cost is reduced, the material utilization rate is improved, and the thermodynamic performance of the nuclear fuel element is enhanced. Meanwhile, the structural design and the manufacturing integrated forming of the workpiece can be realized, and the repeated digital die repairing and the verification of the printed workpiece can be realized, so that the development period is shortened, the development cost is saved, and the method is an effective technical scheme for the low-cost rapid forming and manufacturing of the nuclear fuel element. In a word, according to the preparation method of the nuclear fuel element, the tungsten-based fuel element suitable for nuclear heat propulsion is prepared by a 3D printing forming technology, so that the design is flexible, the process is simple, the forming speed is high, the utilization rate of raw materials is improved, and the preparation cost of the nuclear fuel element is greatly reduced.
Drawings
Fig. 1 is a schematic view of a method of manufacturing a nuclear fuel element according to a preferred embodiment of the present invention.
Fig. 2 shows fuel particles placed on a first tungsten template.
Fig. 3 shows breakage of the nuclear fuel element prepared in comparative example 1.
Detailed Description
Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Considering the advantages of tungsten with high melting point and suitability for nuclear heat propulsion high-temperature environment, the nuclear fuel element provided by the invention adopts tungsten (such as metal tungsten powder) as a 3D printing raw material to prepare a tungsten fuel-free shell, and tungsten coated uranium oxide particles are used as fuel, so that an ideal fuel form of nuclear heat propulsion metal ceramic fuel is provided.
The traditional coated particles are of a four-layer structure, and are sequentially provided with a fuel core, loose pyrolytic carbon, compact pyrolytic carbon, silicon carbide and compact pyrolytic carbon layers from inside to outside. In contrast, the coating particles of the invention are spherical tungsten coated fuel particles, and the fuel core and the tungsten layer are sequentially arranged from inside to outside. Practice shows that tungsten cladding fuel particles are beneficial to realizing dispersion (uniform distribution) of particles in tungsten as a matrix material in the subsequent element preparation and service processes, agglomeration is avoided, and the fuel particles are difficult to generate a phenomenon of fission product diffusion under the restriction of a compact tungsten cladding layer, and meanwhile, the corrosion of working medium hydrogen to the fuel particles can be prevented.
As shown in fig. 1, a nuclear fuel element according to a preferred embodiment of the present invention includes a fuelling shell 1, a fuelling template zone 2, fuel particles 3 and a matrix material 4.
The fuel-free enclosure 1 is a tungsten enclosure formed by tungsten powder 3D printing. The fuel-free housing 1 here has a spherical, cylindrical, hexagonal, square, rectangular or other profiled configuration.
The fuel-free template area 2 is a tungsten template formed by 3D printing of tungsten powder, and comprises a first tungsten template 21, a second tungsten template 22 and a third tungsten template 23, wherein the first tungsten template 21 is positioned at the bottom layer, the second tungsten template 22 is buckled on the first tungsten template 21, the other second tungsten template 22 is buckled on the second tungsten template 22 below, and the third tungsten template 23 is buckled on the second tungsten template 22 below. The top surface of the first tungsten mold plate 21 has a plurality of fuel site grooves, the top and bottom surfaces of the second tungsten mold plate 22 have a plurality of fuel site grooves, respectively, and the bottom surface of the third tungsten mold plate 23 has a plurality of fuel site grooves. It should be understood that the second tungsten template 22 is shown here as two layers by way of example only and not limitation. It should be appreciated that the thickness of the tungsten template may be adjusted according to the mechanical properties and the like, for example, a wafer thickness of 0.2-1.5mm is feasible. It will be appreciated that the fuel site slots are hemispherical slots, and that since one fuel particle 3 is placed at each site, the diameter of the hemispherical slots may be adjusted according to the diameter of the fuel particle 3, for example, hemispherical slots having diameters between 0.6 and 1.1mm are possible.
The fuel particles 3 are tungsten-coated fuel particles which are respectively accommodated in fuel site grooves opposed to the first tungsten template 21 and the second tungsten template 22, in fuel site grooves opposed to the two second tungsten templates 22, and in fuel site grooves opposed to the second tungsten template 22 and the third tungsten template 23. It will be appreciated that the diameter of the fuel particles 3 may be adjusted as desired, for example diameters between 0.5 and 1.02mm are possible. Typically, the diameter of the fuel particles 3 is slightly smaller than the diameter of the hemispherical grooves of the fuel site grooves.
The matrix material 4 is tungsten powder, which fills in the gaps between adjacent fuel particles 3. It will be appreciated that the spacing between adjacent fuel particles 3 may vary depending on the size of the matrix material 4, for example a spacing between 0.1 and 0.3mm is possible.
The preparation method of the nuclear fuel element of the invention firstly comprises the step of printing the fuel-free shell 1 by tungsten powder by adopting 3D printing equipment. The 3D printing apparatus herein is a printing apparatus using at least one of the following technologies: photo-curing molding technique, three-dimensional printing molding technique, inkjet printing molding technique, laser selective sintering molding technique, laser selective melting molding technique, direct metal laser sintering molding technique, and electron beam fuse deposition molding technique.
The method of manufacturing a nuclear fuel element of the present invention next includes printing a first tungsten stencil 21 (see fig. 2) with tungsten powder. It should be appreciated that the size of the fuel site slots on the top surface of the first tungsten template 21 is dependent on the size of the fuel particles 3, and the distribution of the fuel site slots on the first tungsten template 21 may be randomly or orderly distributed according to the design of the fuel particles 3.
The method of manufacturing a nuclear fuel element according to the invention next comprises placing a first tungsten template 21 in the fuel-free enclosure 1, then mounting the fuel particles 3 on the fuel site slots, and then filling the voids with matrix material 4.
The method of manufacturing a nuclear fuel element of the present invention next includes printing a second tungsten template 22 by tungsten powder, then placing the second tungsten template 22 in the fuel-free enclosure 1 such that the tops of the fuel particles 3 are received in the fuel site grooves on the bottom surface of the second tungsten template 22, then mounting the fuel particles 3 on the fuel site grooves on the top surface of the second tungsten template 22, and then filling the gaps with the base material 4.
The method of manufacturing a nuclear fuel element according to the present invention next comprises printing the second tungsten pattern plate 22 by repeating the operation, then placing the second tungsten pattern plate 22 in the fuel-free case 1 such that the top of the fuel particles 3 are accommodated in the fuel site groove on the bottom surface of the second tungsten pattern plate 22, then mounting the fuel particles 3 on the fuel site groove on the top surface of the second tungsten pattern plate 22, and then filling the gap with the base material 4 until the design layer number requirement is reached.
The method of manufacturing a nuclear fuel element according to the present invention next comprises printing a third tungsten template 23 as a sealing portion by tungsten powder, then placing the third tungsten template 23 in the fuel-free case 1 such that the tops of the fuel particles 3 are accommodated in a fuel site groove on the bottom surface of the third tungsten template 23, and sealing to obtain a preform body.
The preparation method of the nuclear fuel element finally comprises the step of carrying out heat treatment on the preformed blank body to obtain the nuclear fuel element. It should be understood that the heat treatment herein includes a sintering treatment and a densification treatment. Preferably, the temperature of the sintering process is set in accordance with the material properties. Preferably, the densification treatment may be achieved by an in situ reaction. That is, the heat treatment may be one step (e.g., densification during sintering of the material), or may be two steps (e.g., densification during heat treatment may be achieved by in situ reaction of the material with the addition of an additive) to ultimately provide the thermodynamic properties of the nuclear fuel element. It will be appreciated that the fraction of the total volume of the fuel particles 3 (the fill factor, loading) of the nuclear fuel element may be adjusted between 11% and 60%. Preferably, the fill factor is between 15% -45%. The nuclear fuel element of the present invention is advantageous over a 10% fill factor of a conventional nuclear fuel element for a gas cooled reactor. Practice shows that the filling factor is lower than 11%, the loading capacity of the fuel particles 3 is too low, more nuclear fuel elements are needed to be put into the reactor to realize the critical of the reactor, the filling factor is higher than 60%, the loading capacity is too high, the elements are easy to crack, and the forming is difficult.
Example 1
The three-dimensional model without the fuel shell and with the dot site template is designed by using computer aided software (such as Pro/Engineering, unigraphics, CATIA, solidworks, etc.), and then sliced (using Magics, mimics, etc.) to import the contour into the 3D printing device.
The cylindrical barrel-shaped fuel-free shell 1 is formed by printing by adopting EOS tungsten printing equipment, the outer diameter of the shell is 12.7mm, the wall thickness is 1.5mm, and the bottom thickness is 2mm.
The tungsten wafer (the diameter of the wafer is slightly smaller than the inner diameter of the cylindrical barrel) with the inner diameter of the cylindrical barrel is printed as a first tungsten template 21, the thickness is 1.5mm, hemispherical groove sites with the diameter of 1mm and the interval of 0.2mm are printed, and the coated fuel particles are conveniently placed in the next step, and the particle diameter is 0.92mm.
The printed tungsten wafer is placed in the cylinder cavity and the fuel particles 3 are placed at each site. A layer of tungsten powder 4 is spread to be loosely filled among the fuel particles 3, so that the subsequent densification and sintering are facilitated.
A second layer of tungsten wafer is printed as a second tungsten template 22, and hemispherical site grooves are printed on the upper surface and the lower surface of the second layer of tungsten wafer, so that the second layer of tungsten wafer is conveniently buckled with the first layer of particles and the first tungsten template 21.
A printed second layer of tungsten wafer was placed in the cylinder cavity and fuel particles 3 were placed at each site. And a layer of tungsten powder 4 is paved, so that the subsequent densification sintering is facilitated.
And (3) repeating the above operation in sequence, placing the mixture on thirteen layers of fuel particles 3, and beginning to print a third tungsten template 23 as an upper cover seal, wherein groove sites corresponding to the fuel particles 3 are printed on the bottom of the seal layer, so as to obtain a preformed blank body.
The preform body was heat treated to obtain the final nuclear fuel element having a particle packing factor of 24.8vol%.
Comparative example 1
And preparing the fuel element with the coated particles dispersed in the zirconium carbide matrix by adopting a hot pressing method.
And weighing zirconium carbide powder and yttrium oxide powder with certain mass, and uniformly mixing to obtain matrix powder.
And weighing coated particles (zirconium oxide microspheres are used for avoiding radioactivity in experiments to replace uranium oxide microspheres) with a certain mass, uniformly mixing the coated particles with the matrix powder to obtain a mixture of fuel particles and the matrix powder, filling the mixture into a mold, and stirring the mixture to prevent the particles from settling.
And preparing the fuel element with the coated particles dispersed in the zirconium carbide matrix by adopting a plasma discharge sintering process. The pressure was 0.3t and the sintering temperature was 1800 ℃.
As shown in fig. 3, the prepared sample had a certain degree of cracking phenomenon, and the internal fuel particles were partially broken.
Comparative example 2
And preparing the fuel element with tungsten coated particles dispersed in a tungsten matrix by adopting a plasma discharge sintering process.
Preparation process as in comparative example 1, a fuel element in which tungsten-coated particles are dispersed in a tungsten matrix was prepared using a plasma discharge sintering process. The pressure was 0.3t and the sintering temperature was 1800 ℃.
The results show that the fuel element can be shaped, but the tungsten coated particles within the tungsten matrix are deformed by compression, in the shape of an ellipse.
The hot pressing method is not suitable for preparing the fuel element with tungsten coated particles dispersed in a tungsten matrix, and has the problem of tungsten fuel particle deformation.
Comparative example 3
Tungsten is used as a matrix UO 2 and is used as fuel particles, a shell is designed to be tungsten, a spherical fuel element with UO 2 particles densely packed is arranged in the shell, and a numerical simulation method is adopted to analyze the heat transfer of the fuel element. The heat transfer performance of tungsten-based fuel spheres was analyzed from the melting point and thermal conductivity of the materials, and the results showed that: the heat transfer performance of the tungsten-based fuel sphere is inferior to that of the tungsten-based fuel sphere which is dispersed and distributed by the template method in the invention due to the low melting point and low heat conductivity of the UO 2. Finite element calculations indicate that there are more severe localized hot spots inside tungsten-based fuel spheres.
Both comparative examples 1 and 2 illustrate that in the conventional hot pressing method for preparing ceramic-based and tungsten-metal-based fuel elements, there are phenomena of difficulty in molding and easy deformation and breakage of fuel particles, and high loading and uniform distribution of the fuel particles cannot be achieved. Comparative example 3 illustrates that although close packing of fuel particles achieves high loading of fuel particles, it is difficult to achieve uniform distribution of fuel particles, localized hot spots are easily formed, and thus safe and stable release of nuclear heat during the life of fuel particles cannot be achieved.
The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and various modifications can be made to the above-described embodiment of the present invention. All simple, equivalent changes and modifications made in accordance with the claims and the specification of this application fall within the scope of the patent claims. The present invention is not described in detail in the conventional art.

Claims (10)

1. A method of manufacturing a nuclear fuel element, the method comprising the steps of:
s1, printing a fuel-free shell through tungsten powder by adopting 3D printing equipment;
S2, printing a first tungsten template with a fuel site groove on the top surface through tungsten powder, placing the first tungsten template in a fuel-free shell, loading tungsten coated fuel particles on the fuel site groove, and filling gaps by using the tungsten powder;
S3, printing a second tungsten template with fuel site grooves on the bottom surface and the top surface through tungsten powder, placing the second tungsten template in a fuel-free shell, enabling the tops of tungsten coated fuel particles below to be contained in the fuel site grooves on the bottom surface of the second tungsten template, placing the tungsten coated fuel particles on the fuel site grooves on the top surface of the second tungsten template, and filling gaps by using tungsten powder;
S4, repeating the step S3 for a plurality of times;
s5, printing a third tungsten template with a fuel site groove on the bottom surface through tungsten powder as a sealing part, placing the third tungsten template in a fuel-free shell, and enabling the tops of tungsten coated fuel particles below to be contained in the fuel site groove on the bottom surface of the third tungsten template, so as to obtain a preformed blank;
and S6, performing heat treatment on the preformed blank body to obtain the nuclear fuel element.
2. The method of claim 1, wherein the fuel-free housing is spherical, cylindrical, hexagonal, square or rectangular.
3. The method of claim 1, wherein the tungsten coated fuel particles are a fuel core and a tungsten layer in that order from the inside to the outside.
4. The method of claim 1, wherein the second tungsten template is snapped onto the first tungsten template and the third tungsten template is snapped onto the second tungsten template.
5. The method of claim 1, wherein the first, second, and third tungsten templates have a thickness of between 0.2 mm and 1.5mm.
6. The method of claim 1, wherein the tungsten coated fuel particles are spherical and the fuel site slots are hemispherical slots, and wherein the diameter of the tungsten coated fuel particles is less than the diameter of the hemispherical slots.
7. The method of claim 6, wherein the tungsten coated fuel particles have a diameter of between 0.5 mm and 1.02mm and the hemispherical grooves have a diameter of between 0.6 mm and 1.1 mm.
8. The method of claim 1, wherein the spacing between adjacent tungsten coated fuel particles is between 0.1 and 0.3 mm.
9. The method of claim 1, wherein the tungsten coated fuel particles comprise between 11% and 60% of the total volume fraction of the nuclear fuel element.
10. The production method according to claim 1, wherein the heat treatment includes a sintering treatment and a densification treatment.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106631112A (en) * 2016-12-29 2017-05-10 中国科学院上海应用物理研究所 Preparation method of hollow ceramic microsphere
CN112091217A (en) * 2020-11-12 2020-12-18 陕西斯瑞新材料股份有限公司 Method for manufacturing copper-tungsten material by adopting spherical tungsten powder laser 3D printing

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2773197A1 (en) * 2012-03-27 2013-09-27 Yundong Li Electroplated super abrasive tools with the abrasive particles chemically bonded and deliberately placed, and methods for making the same
JP2016011432A (en) * 2014-06-27 2016-01-21 セイコーエプソン株式会社 Production method of sintered part, sintered part and fuel cell
JP2020140778A (en) * 2019-02-26 2020-09-03 住友金属鉱山株式会社 Method for manufacturing positive electrode active material for lithium ion secondary battery, positive electrode active material for lithium ion secondary battery, and lithium ion secondary battery
CN112846228B (en) * 2020-12-31 2023-05-30 中核建中核燃料元件有限公司 Selective laser melting forming method for supporting-free local lower tube seat of nuclear fuel assembly
CN114951691B (en) * 2022-03-28 2023-07-18 上海大学 Laser additive manufacturing method of ZrC particle reinforced FeCrAl metal matrix composite for nuclear fuel cladding

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106631112A (en) * 2016-12-29 2017-05-10 中国科学院上海应用物理研究所 Preparation method of hollow ceramic microsphere
CN112091217A (en) * 2020-11-12 2020-12-18 陕西斯瑞新材料股份有限公司 Method for manufacturing copper-tungsten material by adopting spherical tungsten powder laser 3D printing

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