Publications
Showing 172 results for Author: Nidia C. Gallego
Aug, 2026
Journal
Investigation of nonlinear mechanical behavior of two superfine-grained graphites with DIC assisted disc splitting test
Using standardized uniaxial tensile test specimens is not practical due to the limited volumes in irradiation capsules, molten salt degradation facilities, or oxidation apparatus. The ASTM International Standard Test Method for Tensile Strength Estimate by Disc Compression of Manufactured Graphite (ASTM D8289) was developed to provide a convenient way for estimating tensil…
Jun, 2026
Journal
Sliding friction and wear behavior of nuclear graphite in high temperature inert environment: Influence of contact load, speed and temperature
Repeated dynamic interactions of graphitic components in pebble-bed gas-cooled nuclear reactors can cause abrasive wear-induced pebble surface damage, generate hazardous fine graphite debris, and alter fuel circulation dynamics due to changes in friction behavior. Comprehensive tribological characterization of nuclear graphitic materials in conditions relevant to reactor o…
Jun, 2026
ORNL Report
Tribological behavior of nuclear graphite in high-temperature inert environment
May, 2026
ORNL Report
Status on Microstructural Studies of Nuclear Graphite
This report documents the completion of the Advanced Reactor Technologies (ART) Level 3 Milestone (M3AT-26OR0605054), “Provide status on microstructural studies of nuclear graphite,” due May 1, 2026. The contents of this report summarize recent progress in the development of the Nuclear Graphite Microstructure Library, including datasets that have been generated, curated,…
Mar, 2026
Conference Paper
Microstructural characterization of the oxidation of nuclear graphite under chronic and accident conditions via XCT and synchrotron XCT
Graphite is a candidate material to moderate fast neutrons and for structural components in the US next-generation graphite-moderated reactors. A graphite core is conceived as a large formation of interconnected bricks that primarily serves as the moderator of fast neutrons, holds instrumentation, fuel elements, control rods, and is a receptacle for molten salts for Molten…
Dec, 2025
Journal
Evolved Gas Analysis–Mass Spectrometry Exposes Polymer Network Structures
Polymer network structures in epoxy thermosets play an important role in the final thermoset material properties. However, analytical characterization of these network structures is difficult due to their amorphous nature. In this work, the application of evolved gas analysis–mass spectrometry (EGA-MS) to characterize the polymer network structures of bisphenol A (BPA)-bas…
Dec, 2025
Journal
Viewing is understanding: Graphite microstructure effects on infiltrated molten salt distribution revealed by 3D neutron tomography
Molten salt infiltration in the pore network of nuclear graphite may cause unwanted changes to graphite's local structure and mechanical and thermal properties. A detailed and comprehensive understanding of molten salt intrusion (distribution across sample cross section and penetration depth) is needed to assess its effects. In this work, we report on an improved methodolo…
Oct, 2025
Journal
Effects of chemical composition and physicochemical properties of poplar biomass on the performance of 3D printed poplar-reinforced PLA materials
Lignocellulosic biomass has been well-acknowledged as a filler for making 3D printed composites. The technical performances of composites were influenced by the characteristics of the components. The correlations between poplar biomass properties and the mechanical and thermal performances of the 3D printed poplar-plastic composites were investigated. The characteristics o…