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Leckie, Rafael M.

Publications and source records attributed to Leckie, Rafael M..

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Evaluation of LANL Capabilities for Fabrication of TREAT Conversion Fuel

This report estimates costs and schedule associated with scale up and fabrication of a low-enriched uranium (LEU) core for the Transient Reactor Test Facility (TREAT) reactor. This study considers facilities available at Los Alamos National Laboratory, facility upgrades, equipment, installation and staffing costs. Not included are costs associated with raw materials and off-site shipping. These estimates are considered a rough of magnitude. At this time, no specifications for the LEU core have been made and the final schedule needed by the national program. The estimate range (+/-100%) reflects this large uncertainty and is subject to change as the project scope becomes more defined.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2014

Update on Fabrication of Extrusions for TREAT Trade Study

This supplemental report describes fuel fabrication efforts conducted for the Idaho National Laboratory Trade Study for the TREAT Conversion project that is exploring the replacement of the HEU (Highly Enriched Uranium) fuel core of the TREAT reactor with LEU (Low Enriched Uranium) fuel. Previous reports have documented fabrication of fuel by the “upgrade” process developed at Los Alamos National Laboratory. These experiments supplement an earlier report that describes efforts to increase the graphite content of extruded fuel and minimize cracking.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2014

Fabrication of TREAT Fuel with Increased Graphite Loading

As part of the feasibility study exploring the replacement of the HEU fuel core of the TREAT reactor at Idaho National Laboratory with LEU fuel, this study demonstrates that it is possible to increase the graphite content of extruded fuel by reformulation. The extrusion process was use to fabricate the “upgrade” core1 for the TREAT reactor. The graphite content achieved is determined by calculation and has not been measured by any analytical method. In conjunction, a technique, Raman Spectroscopy, has been investigated for measuring the graphite content. This method shows some promise in differentiating between carbon and graphite; however, standards that would allow the technique to be calibrated to quantify the graphite concentration have yet to be fabricated. Continued research into Raman Spectroscopy is on going. As part of this study, cracking of graphite extrusions due to volatile evolution during heat treatment has been largely eliminated. Continued research to optimize this extrusion method is required.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2013

Report on Evolutionary Enhancements to UO 2 Pellets

Sintered uranium oxide fuel pellets are the primary fuel used in civilian nuclear reactors. Due to extensive experience and established infrastructure, these ceramic fuels are likely to remain important for nuclear energy well into the future. Fuel pellets are produced mainly through cold-pressing ceramic powder and high temperature sintering. The processing technique presented here is designed to fit into the current fuel pellet production infrastructure with minimal changes to fuel manufacturers and reactor operators. This study makes changes in the UO 2 powder before the pellets are pressed, possibly requiring only minor changes in the manufacturing process.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2012

Report on Controlling the Microstructure of UO 2 Pellets

Most civilian reactors in use today use sintered uranium oxide pellets for fuel. This is an established technology with decades of experience and a large infrastructure behind it. As such, these ceramic fuels are expected to remain an important part of nuclear energy production for the foreseeable future.

Energy Sciences↗