IP Library Granted Patent US 12,437,891
Granted Patent B2
US 12,437,891 · App. 18/386,031 · Granted Oct 7, 2025

Using additive manufacturing in creating a nuclear fuel structure with a shape corresponding to a mathematically-based periodic solid having a triply periodic minimal surface

Inventors: Benjamin D. Fisher (Lynchburg, VA); John R. Salasin (Lynchburg, VA); Craig D. Gramlich (Forest, VA); Jonathan K. Witter (Forest, VA)
Assignee: BWXT Advanced Technologies LLC
G21C21/02G21C3/044
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,437,891
App. No.
18/386,031
Granted
Oct 7, 2025
Kind
B2
Abstract

A method of manufacturing a nuclear fuel segment includes varying a parameter of a lattice structure of a first mathematically-based periodic solid to form a second mathematically-based periodic solid. The second mathematically-based periodic solid comprises a triply periodic minimal surface (TPMS). The varying includes varying periodicity, thickness, or bias of the first mathematically-based periodic solid. The second mathematically-based periodic solid is embodied in a gridded mesh. The gridded mesh is sectioned into a plurality of layers. An additive manufacturing process is used to deposit a fissionable fuel composition in creating a body having a structure with a shape corresponding to the second mathematically-based periodic solid. The plurality of layers are used in controlling the additive manufacturing process.

Claims (53)

1. A method of manufacturing a nuclear fuel segment, the method comprising:

varying a parameter of a lattice structure of a first mathematically-based periodic solid to form a second mathematically-based periodic solid, wherein the second mathematically-based periodic solid comprises a triply periodic minimal surface (TPMS) and wherein varying the parameter includes:

varying a periodicity of the first mathematically-based periodic solid,

varying a thickness of the first mathematically-based periodic solid, or

varying a bias of the first mathematically-based periodic solid,

where the bias relates to converging and diverging regions

within the second mathematically-based periodic solid;

embodying the second mathematically-based periodic solid in a gridded mesh;

sectioning the gridded mesh into a plurality of layers; and

using the plurality of layers to control an additive manufacturing process to deposit a fissionable fuel composition to manufacture a body having a structure with a shape corresponding to the second mathematically-based periodic solid.

2. The method of claim 1 , wherein the body having the structure with the shape corresponding to the second mathematically-based periodic solid includes a network of interconnected channels, and

wherein varying the parameter changes a flow rate of a medium flowing through the network of interconnected channels.

3. The method of claim 2 , wherein at least a portion of the interconnected channels of the network of interconnected channels extend from a first outer surface of the body to a second outer surface of the body,

wherein the structure has a volumetric density of 35% to 85%, and

wherein a composition of the structure includes a nuclear fissionable fuel having an enrichment of up to 20%.

4. The method according to claim 3 , wherein a specific enrichment of the structure (% enrichment per unit volume) is constant ±2%.

5. The method according to claim 2 , further comprising depositing a cladding layer on surfaces of the network of interconnected channels.

6. The method according to claim 5 , wherein depositing the cladding layer includes a vapor deposition technique, a chemical vapor deposition technique, electroplating or electroless plating.

7. The method according to claim 5 , wherein the cladding has a composition including molybdenum, tungsten, rhenium, tantalum, hafnium and alloys thereof, including carbides.

8. The method according to claim 5 , wherein the cladding layer has a composition including a steel alloy, a zirconium alloy, a molybdenum-containing metal alloy, a molybdenum-tungsten alloy, Zircaloy-4 or Hastelloy X.

9. The method of claim 1 , wherein varying the parameter changes a neutronic characteristic of a nuclear reactor incorporating a fuel element containing the nuclear fuel segment.

10. The method according to claim 9 , wherein the body having the structure with the shape corresponding to the second mathematically-based periodic solid includes a network of interconnected channels, and

wherein the method further comprises depositing a cladding layer on surfaces of the network of interconnected channels.

11. The method according to claim 10 , wherein depositing the cladding layer includes a vapor deposition technique, a chemical vapor deposition technique, electroplating or electroless plating.

12. The method according to claim 10 , wherein the cladding has a composition including molybdenum, tungsten, rhenium, tantalum, hafnium and alloys thereof, including carbides.

13. The method according to claim 10 , wherein the cladding layer has a composition including a steel alloy, a zirconium alloy, a molybdenum-containing metal alloy, a molybdenum-tungsten alloy, Zircaloy-4 or Hastelloy X.

14. The method of claim 1 , wherein varying the parameter changes a thermal hydraulics characteristic or a stress mechanics characteristic of a nuclear reactor incorporating a fuel element containing the nuclear fuel segment.

15. The method according to claim 14 , wherein the body having the structure with the shape corresponding to the second mathematically-based periodic solid includes a network of interconnected channels, and

wherein the method further comprises depositing a cladding layer on surfaces of the network of interconnected channels.

16. The method according to claim 15 , wherein depositing the cladding layer includes a vapor deposition technique, a chemical vapor deposition technique, electroplating or electroless plating.

17. The method according to claim 15 , wherein the cladding has a composition including molybdenum, tungsten, rhenium, tantalum, hafnium and alloys thereof, including carbides.

18. The method according to claim 15 , wherein the cladding layer has a composition including a steel alloy, a zirconium alloy, a molybdenum-containing metal alloy, a molybdenum-tungsten alloy, Zircaloy-4 or Hastelloy X.

19. The method according to claim 1 , wherein at least a portion of the interconnected channels of the network of interconnected channels extend from a first outer surface of the body to a second outer surface of the body,

wherein the structure has a volumetric density of 35% to 85%, and

wherein a composition of the structure includes a nuclear fissionable fuel having an enrichment of up to 20%.

20. The method according to claim 19 , wherein a specific enrichment of the structure (% enrichment per unit volume) is constant ±2%.

21. The method according to claim 19 , further comprising depositing a cladding layer on surfaces of the network of interconnected channels,

wherein depositing the cladding layer includes a vapor deposition technique, a chemical vapor deposition technique, electroplating or electroless plating.

22. The method according to claim 21 , wherein the cladding has a composition including molybdenum, tungsten, rhenium, tantalum, hafnium and alloys thereof, including carbides.

23. The method according to claim 21 , wherein the cladding layer has a composition including a steel alloy, a zirconium alloy, a molybdenum-containing metal alloy, a molybdenum-tungsten alloy, Zircaloy-4 or Hastelloy X.

24. The method according to claim 1 , wherein the additive manufacturing process includes photopolymerization.

25. The method according to claim 1 , wherein the body is disc-shaped and occupies a volume that includes a radial side surface corresponding to a thickness of the body between a first outer surface and a second outer surface, and wherein the method further comprises placing a side wall radially outward of the radial side surface of the body,

wherein the side wall has a composition including a neutron thermalizing material, and

wherein the neutron thermalizing material has a composition including a zirconium (Zr) alloy, a beryllium (Be) alloy, or graphite.

26. A method of manufacturing a nuclear fuel segment, the method comprising:

varying a parameter of a lattice structure of a first mathematically-based periodic solid to form a second mathematically-based periodic solid, wherein the second mathematically-based periodic solid comprises a triply periodic minimal surface (TPMS) and wherein the varying includes varying:

a periodicity of the first mathematically-based periodic solid,

a thickness of the first mathematically-based periodic solid, and

a bias of the first mathematically-based periodic solid, where the bias relates to converging and diverging regions;

embodying the second mathematically-based periodic solid in a gridded mesh;

sectioning the gridded mesh into a plurality of layers; and

depositing a fissionable fuel composition, via an additive manufacturing process, to manufacture a body having a structure with a shape corresponding to the second mathematically-based periodic solid,

wherein the plurality of layers are used to control the additive manufacturing process.

Assignments (1)
SECURITY INTEREST Recorded Nov 10, 2025
From: BWXT ADVANCED TECHNOLOGIES LLC; BWXT ISOTOPE TECHNOLOGY GROUP, INC.; BWXT NUCLEAR ENERGY, INC.
To: WELLS FARGO BANK, NATIONAL ASSOCIATION, AS ADMINISTRATIVE AGENT
Reel/Frame 073531/0358 →
Continuity (4)
Continuation 17852434 · Jun 29, 2022
Division 16835388 · Mar 31, 2020
Provisional Application 62827706 · Apr 1, 2019
Related Publication 20240266077A1 · Aug 8, 2024
References Cited (35)
US 3145150A · Gylfe · 1964 [cited by applicant]
US 3287225A · Ackroyd et al. · 1966 [cited by applicant]
US 4146430A · Berringer · 1979 [cited by applicant]
US 4983351A · Tower et al. · 1991 [cited by applicant]
US 5349618A · Greenspan · 1994 [cited by applicant]
US 5991354A · Van Swam · 1999 [cited by applicant]
US 8526566B1 · Youchison et al. · 2013 [cited by applicant]
US 8920871B1 · Youchison et al. · 2014 [cited by applicant]
US 9793010B2 · van Staden · 2017 [cited by applicant]
US 10664560B2 · Pal · 2020 [cited by examiner]
US 20120140868A1 · Kauchi et al. · 2012 [cited by applicant]
US 20140334595A1 · Bashkirtsev et al. · 2014 [cited by applicant]
US 20170263345A1 · Venneri et al. · 2017 [cited by applicant]
US 20200027578A1 · O'Brien · 2020 [cited by applicant]
US 20200353681A1 · Fisher et al. · 2020 [cited by applicant]
US 20200373024A1 · Gramlich · 2020 [cited by applicant]
JP 2004301831A · 2004 [cited by applicant]
JP 2016517964A · 2016 [cited by applicant]
WO 2015200257A1 · 2015 [cited by applicant]
WO 2017192508A1 · 2017 [cited by applicant]
Haertling et al., “Literature review of thermal and radiation performance parameters for high-temperature, uranium dioxide fueled cermet materials”, J. of Nuc. Mat., 366 (2007) 317-335; https://doi.org/10.1016/j.jnucmat… [cited by applicant]
Hickman et al., “Fabrication and Testing of CERMET Fuel Materials for Nuclear Thermal Propulsion”, 48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit (Jul. 30-Aug. 1, 2012), 5 pages; https://doi.org/10.2514/6… [cited by applicant]
Hodkin et al., “Surface and Interfacial Properties of Non-Stoichiometric Uranium Dioxide”, J. of Nuc. Mat., 67 (1977) 171-180. [cited by applicant]
Kumar, “Development, Fabrication, and Characterization of Fuels for the Indian Fast Reactor Programme”, Fast Reactors and Related Fuel Cycles International Conferences, pp. 17-31 (2013). [cited by applicant]
Wongsawaeng et al., “Liquid-Metal Bond for LWR Fuel Rods”, Nuclear Technology, (2007) 159:3, 279-291; doi:10.13182/NT07-A3876. [cited by applicant]
Eustathopoulos, “Wetting by Liquid Metals—Application in Materials Processing: The Contribution of the Grenoble Group”, Metals 2015, 5, 350-370 .; doi:10.3390/met5010350. [cited by applicant]
Next generation design & engineering software, 15 pages; retrieved from the internet: <URL: https://www.ntopology.com/>. [cited by applicant]
Brakke, Triply Periodic Minimal Surfaces; retrieved from the internet: <URL: http://facstaff.susqu.edu/brakke/evolver/examples/periodic/periodic.html>. [cited by applicant]
Lattice Topologies, Autodesk Knowledge Network (Mar 21, 2017) 8 pages, retrieved from the internet: <URL: http://help.autodesk.com/view/NETF/2017/ENU/?guid=GUID-A738117A-64B1-4613-A904-FDB6130E2EDD>. [cited by applicant]
Olander et al., “Hybride fuel behavior in LWRs”, J. of Nuc. Mat., 346 (2005) 98-108. [cited by applicant]
International Search Report and Written Opinion issued on Jan. 5, 2021 in PCT/US20/25948. [cited by applicant]
Szuta, “Modelling of Helium release from the highly burned fuel during annealing and impact on its migration in the Uranium Dioxide fuel during neutron irradiation”, International conference on WWER fuel performance, mo… [cited by applicant]
Extended European Search Report issued on Feb. 16, 2023 in European Application No. 20834323.6. [cited by applicant]
Office Action dated Feb. 20, 2024, issued in corresponding Japanese Patent Application No. 2021-560451. [cited by applicant]
Office Action dated Mar. 5, 2025, issued in corresponding Japanese Patent Application No. 2024-094414. [cited by applicant]