Ceramics for a New Generation of Nuclear Energy Systems and Applications: Ceramics for Nuclear Energy Application
Sponsored by: TMS Nuclear Materials Committee, ACerS Energy Materials and Systems (EMSD) Division
Program Organizers: Ming Tang, Clemson University; Enrique Martinez Saez, Clemson University; Yongfeng Zhang, University of Wisconsin; Krista Carlson, University of Nevada, Reno; Yutai Katoh, Oak Ridge National Laboratory; Jean Paul Crocombette, CEA Saclay; Erofili Kardoulaki, Los Alamos National Laboratory; Levi Gardner, Argonne National Laboratory; Jian Zhang, Xiamen University; Charmayne Lonergan, Missouri University of Science and Technology
Wednesday 8:00 AM
October 12, 2022
Room: 329
Location: David L. Lawrence Convention Center
Session Chair: Maik Lang, University of Tennessee; S. K. Sundaram, Alfred University
8:00 AM Invited
Additive Manufacturing of Ceramics for Nuclear Applications: S. K. Sundaram1; 1Alfred University
Additive manufacturing (AM) of ceramics can revolutionize rapid production of various materials for nuclear applications. Cerium oxide (ceria), fully stabilized 8 mol % yttria-stabilized zirconia (YSZ), and lithium silicate ceramics are studied using a Lithoz CeraFab 8500 lithography-based ceramic slurry 3D-printer to produce monolithic dense ceramic parts. Characteristics such as grain size, porosity, stoichiometry, and density were used to compare printed samples with traditionally processed and sintered counterparts. Main parameters varied are powder particle size, solid loading of the slurry, sintering temperature, and orientation of layers printed. Ceria powders with a particle size of 0.5 μm and slurry solid loading of 41.5 vol% produced high-density ceramics with complex structures and geometries with a maximum of 98% theoretical density. We achieved average theoretical density of 98 % for YSZ and 84 % for lithium silicate ceramics. The presentation will summarize our results, lessons learned, and potential for scale up.
8:30 AM Invited
Radiation Effects in Single-crystal High-entropy Oxides: Candice Kinsler-Fedon1; Lauren Nuckols1; Anamul Mir2; Christopher Nelson3; David Mandrus1; Yanwen Zhang3; Veerle Keppens1; William Weber1; 1University of Tennessee; 2University of Huddersfield; 3Oak Ridge National Laboratory
High-entropy pyrochlore oxides have recently gained recognition for their low thermal conductivity and tunable mechanical capabilities, but little is known about their irradiation behavior. In this work, the heavy-ion irradiation response of single-crystal, high-entropy oxides (HEO) with the pyrochlore structure have been investigated. The damage accumulation behavior at 300 K due to 4 MeV Au ion irradiation of a <100>-oriented HEO single crystal has been investigated by Rutherford backscattering spectrometry in channeling mode. Transmission electron microscopy with in situ irradiation using 600 keV Xe ions has been employed to determine the temperature dependence of amorphization in the same HEO composition. In another HEO single-crystal composition, the amorphization due to 23 MeV Ni ions has been characterized by Raman spectroscopy. The results obtained on these HEO pyrochlores are compared to those of single-component pyrochlores.
9:00 AM
Radiation Damage of Ion-irradiated High Entropy Ceramics: Kun Wang1; Yonggang Yan1; Di Chen1; 1Alfred University
Ultrahigh temperature ceramics, such as carbide and boride, exhibited exceptional high-temperature thermomechanical properties. Also, the emerging high entropy materials have indicated superior radiation tolerance. Therefore, high entropy ceramics (HECs) are supposed to be excellent candidate materials for advanced nuclear reactors. However, the radiation response of HECs is still not well investigated. Herein, we fabricate bulk HECs including carbide and boride by mechanical alloying and spark plasma sintering (SPS). The HECs are irradiated by heavy-ion or helium-ion under various irradiation conditions. The radiation hardening is investigated by nanoindentation. The microstructural evolution, including radiation-induced dislocation loops, cavities, segregation, phase stability etc., is interrogated using analytical scanning/transmission electron microscopy (S/TEM), and atom probe tomography (APT). The radiation response of HECs will be compared with the binary ceramics. The results of this work will provide insights into the radiation behavior of HECs under extreme irradiation environments.
9:20 AM
Phonon Broadening in High Entropy Ceramic Carbide: Linu Malakkal1; Kaustubh Bawane1; Cody Dennet2; Zilong Hua1; Lingfeng He1; Yongfeng Lu3; Bai Cui3; 1Idaho National Laboratory; 2Commonwealth Fusion Systems; 3University of Nebraska-Lincoln
In the quest for novel irradiation-resistant and high-temperature tolerant ceramic materials for nuclear applications, the high entropy ceramic carbide materials with outstanding properties are a promising material class. At high temperatures, material properties such as thermal stability, thermodynamic, elastic property, and thermal conductivity are critically influenced by atomic vibrations (phonons). In a crystalline ceramic, carbides with an extreme disorder of cations can induce significant phonon scattering and broadening, owing to the inherently present mass and force constant variances. Despite the importance, phonon scattering and broadening in high entropy ceramic carbide are still lacking. Hence, in this work, we use the abinitio calculations to systematically investigate the impact of the mass and force constant variance on the phonon spectral function of face-centered cubic HECC, from binaries up to 5-component high entropy alloys, addressing the key question of how chemical complexity impacts the phonons
9:40 AM Invited
A Physics-Based Cluster Dynamics Model of Radiation-Enhanced Growth of Oxides: Aaron Kohnert1; Edward Holby1; Amitava Banerjee2; Shivani Srivastava3; Mark Asta3; Blas Uberuaga1; 1Los Alamos National Laboratory; 2IIT Jodhpur; 3University of California, Berkeley
Materials intended for nuclear environments can experience a number of harsh conditions, including irradiation and corrosion. There is still relatively little known about how radiation-induced defects impact the corrosive growth of oxides. To remedy this gap, we have developed a cluster dynamics model that accounts for radiation-enhanced diffusion, the variability in charge states of defects as a function of the local electronic structure of the material, and the formation of space-charge regions that create electric fields and thus induce electromigration. Using this model, we demonstrate the impact of radiation damage on Fe2O3 hematite, where the defect thermokinetic parameters are determined using density functional theory and reproduce thermal oxide growth behavior. We find that irradiation has a large effect on oxide growth rates and that complex defect profiles evolve across the oxide. This work emphasizes the synergies between irradiation and corrosion.
10:10 AM Break
10:30 AM Invited
Characterization of Radiation Effects in Ceramics with Spallation Neutron Probes: Maik Lang1; 1University of Tennessee
The development of durable materials for radionuclide immobilization has been central to efforts to dispose of nuclear wastes. There still exist, however, large gaps in the understanding of waste form degradation under self-irradiation. Neutron total scattering measurements with pair distribution function analysis can be utilized to uniquely characterize radiation effects in a wide range of wasteform materials. This enables detailed analysis of both cation and anion defect behavior, and short-range order, which is important for the investigation of amorphous materials. Recent results for several oxides demonstrate that radiation effects are more complex than previously thought with distinct processes occurring over different length scales. For example, disordered pyrochlore and spinel are composed of local structural units that maintain atomic order and exist in configurations that are different than the expected average structure. Here we will highlight the importance of short- and medium-range analysis for a comprehensive description of radiation behavior.
11:00 AM
Comparison of ZrC-TZM Mechanical and Structural Properties Before and After Extended Carbon Exposure: Peyton McGuire1; Erofili Kardoulaki2; Ming Tang1; 1Clemson University; 2Los Alamos National Laboratory
Mo alloy TZM has demonstrated favorable mechanical properties for use in high-temperature environments. However, carbon exposure in-service can carburize TZM and alter its mechanical properties. Ceramic coatings for TZM are considered to help strengthen the overall system, with particular emphasis being placed upon zirconium carbide (ZrC) due to its high-temperature stability and favorable mechanical properties. In this work, ZrC was coated on a TZM substrate through chemical vapor deposition. The sample was exposed to graphite for 40 days at 1000°C to test the carburization resistance the coating can offer. Samples were analyzed using nanoindentation and TEM/STEM techniques. The hardness and elastic moduli of both exposed and non-exposed coatings/substrates were analyzed and compared against literature to see whether or not the exposure to carbon had significantly affected the structural and/or mechanical properties, and if such a difference would affect the use of ZrC as a protective coating of TZM claddings.
11:20 AM
Characterizing Effects of Aging Bismuth Laden Sorbents in NOx Atmosphere for Radioiodine Capture: Casey Elliott1; Karthikeyan Baskaran1; Muhammad Ali1; Dave Cohrs1; Brian Riley2; Krista Carlson1; 1University of Nevada Reno; 2PNNL
Off-gas streams in nuclear fuel reprocessing contain harmful radioiodine-129 (I129) carried by NO and NO2 (NOx). Novel sorbents loaded with bismuth via several methods were investigated for their capture capabilities of I129 before and after exposure to NOx. Sorbents included novel aerogels synthesized using tetraethoxysilane (TEOS) and soybean oil, quartz microfiber filters, and a novel carbon foam. Bismuth was loaded onto the substrates via hydrothermal or electroplating methods. The sorbents were exposed to NO and NO2 until fully saturated (aged). The physical and chemical properties of the sorbents were categorized after aging through a variety of advanced techniques. The overall iodine loading capacity of each sorbent was determined after NOX aging.
11:40 AM
Modeling Vibrational Modes in Raman Spectra of ThO2: Saqeeb Adnan1; Joshua Ferrigno1; Erika Nosal1; Chao Jiang2; Marat Khafizov1; 1The Ohio State University; 2Idaho National Laboratory
Vibrational properties are key to understanding thermal transport in thorium dioxide (ThO2). Raman spectroscopy provides a convenient approach to characterize selected vibrational modes in fluorite oxides. While analysis of Raman spectra of the irradiated fluorite oxides is becoming a common characterization tool, the origin of the irradiation-induced defect peaks remains controversial. We present a first-principles calculation based on defect symmetry to isolate the contribution of different defects to experimentally observed Raman peaks. The analysis focuses on isolating specific atomic bonds contributing to the emergence of the Raman peaks. In particular, the Longitudinal Optical (LO) peak, that has been commonly attributed to the presence of oxygen vacancy is assigned to a stretching motion of the O-O bond nearest to the vacancy site. This Raman peak analysis provides better insight into the origin of the different vibrational modes and opens up possibilities for the validation of microstructure evolution models in irradiated fluorites.