Emergent Materials under Extremes and Decisive In Situ Characterizations: Decisive In-situ Characterizations
Sponsored by: ACerS Basic Science Division
Program Organizers: Xiaofeng Guo, Washington State University; Xujie Lu, Center for High Pressure Science & Technology Advanced Research; Hua Zhou, Argonne National Laboratory; Judith Driscoll, University of Cambridge; Hongwu Xu, Los Alamos National Laboratory
Wednesday 2:00 PM
November 4, 2020
Room: Virtual Meeting Room 36
Location: MS&T Virtual
Session Chair: Hongwu Xu, Los Alamos National Laboratory; Xiaofeng Guo, Washington State University
2:00 PM Invited
Technology Development of In-situ Corrosion Kinetics and Salt Property Measurements: Li Liu1; Jinghua Feng1; Kemal Ramic1; 1Rensselaer Poletechnic Institute
In Concentrating Solar Power, we are developing neutron measurements for in-situ interface corrosion kinetics and molten salt properties. This research will provide fundamental data for material selection including the molten salt systems for both nuclear and solar applications. The presentation will focus on the development of in-situ neutron techniques for fundamental understanding of the mechanisms of molten salt corrosion, and the micro-structural response of containment alloys thereto, to measure the surface corrosion kinetics. We are working on realization and initial application of in-situ techniques for measuring molten salt fundamental properties including molten salt structure, dynamics, and salt density, etc. and the micro-structural and -chemical response of containment alloys to corrosive molten salt environments. While we are designing and manufacturing sample environments for harsh environments (high temperature and corrosive), they will provide great first-of-the-kind experimental data for molten salt systems.
2:30 PM Invited
Characterizing Disordered Crystalline Materials with Pauling’s Rules: Eric O'Quinn1; Kurt Sickafus1; Rodney Ewing2; Gianguido Baldinozzi3; Joerg Neuefeind4; Matthew Tucker4; Antonio Fuentes5; Devon Drey1; Maik Lang1; 1University of Tennessee; 2Stanford University; 3Université Paris-Saclay; 4Oak Ridge National Laboratory; 5Cinvestav Unidad Saltillo
Recently, there has been an increased focus on understanding the structural details of disordered materials which are found across all energy technologies [Shamblin et al., Nat. Mater. 2016]. Despite the importance of these materials, there is still little knowledge about the atomic-scale rules governing disordering processes. Here, we present results from neutron total scattering experiments from spinel (AB2O4) and pyrochlore (A2B2O7) model systems which reveal that short-range ordering and associated structural relaxations in disordered materials can be understood as an extension of Pauling’s rules [Pauling, J. Am. Chem. Soc. 1929]. These rules apply whether disorder is induced intrinsically (e.g., chemical substitution), extrinsically (high temperature), or even by highly non-equilibrium conditions (high-energy ion irradiation and mechanical milling). These results provide a framework that can be utilized to predict the atomic configuration in disordered materials, including those that result from exposure to extreme conditions [O’Quinn et al., In review, Nat. Commun. 2020].
3:00 PM Invited
Investigations of Materials under Extreme Hydrothermal Conditions Using Synchrotron and Complementary Techniques: Robert Mayanovic1; Diwash Dhakal1; Nadib Akram1; Jason Baker2; Xiaofeng Guo3; Hakim Boukhalfa2; Artas Migdissov2; Cheng-Jun Sun4; Hongwu Xu2; 1Missouri State University; 2Los Alamos National Laboratory; 3Washington State University; 4Argonne National Laboratory
Recent advances in synchrotron techniques have given rise to unprecedented growth in studies of materials under extreme conditions. The in-situ measurements afforded by these techniques have increased our fundamental understanding of how extremes in pressure (P) and/or temperature (T) affect phase transformations, the nature of the chemical bond, non-equilibrium phase behavior and other properties of materials. The diamond anvil cell has proven to be an indispensable tool for in-situ studies of materials at extreme PT conditions. Several applications of in-situ synchrotron techniques to the study of materials in extreme environments will be discussed. Examples of studies featured include in-situ SAXS and WAXS measurements made on mesoporous metal oxides and in-situ XAS and high-energy x-ray scattering PDF analysis of aluminosilicate melts under extreme hydrothermal conditions. Complementary in-situ XAS and Raman studies of aqueous uranyl-chloride complex formation and speciation, for a range of Cl– concentrations, at high PT conditions are also described.
3:30 PM
High-speed X-ray Phase Contrast Imaging Analysis of Microscale Shock Response of a Mock Additively Manufactured Energetic Material: Karla Wagner1; Amirreza Keyhani1; Andrew Boddorff1; Gregory Kennedy1; Didier Montaigne2; Matthew Beason3; Brian Jensen3; Min Zhou1; Naresh Thadhani1; 1Georgia Institute of Technology; 2Eglin Air Force Research Lab; 3Los Alamos National Lab
X-ray phase contrast imaging (X-PCI) is used to probe the interior and determine the equation of state of a mock additively manufactured energetic material (AMEM) under dynamic loading. AMEMs have structural characteristics and process-inherent heterogeneities at multiple length scales. Many of these features are difficult to control or avoid, so it is important to understand how they affect AMEMs’ dynamic response. To this effect, X-PCI is a technique that grants insight into micro- and meso- scale processes during a shock event. We use X-PCI results to analyze the shock response of a mock AMEM loaded at several impact conditions. By tracking displacement of the shock front and features behind it, we can determine shock and particle velocities. PDV was also used to measure particle velocities, which correlate well with those obtained from X-PCI. The experiments presented were performed at the Dynamic Compression Sector, in collaboration with Los Alamos National Lab.