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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

Friction Pull Plug Welding in Aluminum Alloys

NASA fs Marshall Space Flight Center (MSFC) has recently invested much time and effort into the process development of Friction Pull Plug Welding (FPPW). FPPW, is a welding process similar to Friction Push Plug Welding in that, there is a small rotating part (plug) being spun and simultaneously pulled (forged) into a larger part. These two processes differ, in that push plug welding requires an internal reaction support, while pull plug welding reacts to the load externally. FPPW was originally conceived as a post proof repair technique for External Tank. FPPW was easily selected as the primary process used to close out the termination hole on the Constellation Program fs ARES I Upper Stage circumferential Self ] Reacting Friction Stir Welds (SR ]FSW). The versatility of FPPW allows it to also be used as a repair technique for both SR ]FSW and Conventional Friction Stir Welds. To date, all MSFC led development has been concentrated on aluminum alloys (2195, 2219, and 2014). Much work has been done to fully understand and characterize the process fs limitations. A heavy emphasis has been spent on plug design, to match the various weldland thicknesses and alloy combinations. This presentation will summarize these development efforts including weld parameter development, process control, parameter sensitivity studies, plug repair techniques, material properties including tensile, fracture and failure analysis.

Brooke, Shane A.↗
DOE OSTI2020

Measurement and Simulation of Vacancy Formation in 2-MeV Self-irradiated Pure Fe

Positron annihilation spectroscopy is a powerful tool to quantify the amount of vacancies and vacancy clusters in materials. The technique has been utilized to study the induced defects in materials after ion beam and neutron irradiations. Here we make the case for how the technique can and should be utilized to quantify the defects created by irradiation in situ during irradiation to foster a more thorough understanding of the surviving defects after initial collision cascades. This paper outlines a future experimental approach and its meaning for the nuclear materials community, being able to benchmark commonly used rate theory models of damage evolution.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Reaction heterogeneity in practical high-energy lithium–sulfur pouch cells

The lithium–sulfur (Li–S) battery is a promising next-generation energy storage technology because of its high theoretical energy and low cost. Extensive research efforts have been made on new materials and advanced characterization techniques for mechanistic studies. However, it is uncertain how discoveries made on the material level apply to realistic batteries due to limited analysis and characterization of real high-energy cells, such as pouch cells. Evaluation of pouch cells (>1 A h) (instead of coin cells) that are scalable to practical cells provides a critical understanding of current limitations which enables the proposal of strategies and solutions for further performance improvement. Herein, we design and fabricate pouch cells over 300 W h kg -1 , compare the cell parameters required for high-energy pouch cells, and investigate the reaction processes and their correlation to cell cycling behavior and failure mechanisms. Spatially resolved characterization techniques and fluid-flow simulation reveal the impacts of the liquid electrolyte diffusion within the pouch cells. We found that catastrophic failure of high-energy Li–S pouch cells results from uneven sulfur/polysulfide reactions and electrolyte depletion for the first tens of cycles, rather than sulfur dissolution as commonly reported in the literature. The uneven reaction stems from limited electrolyte diffusion through the porous channels into the central part of thick cathodes during cycling, which is amplified both across the sulfur electrodes and within the same electrode plane. A combination of strategies is suggested to increase sulfur utilization, improve nanoarchitectures for electrolyte diffusion and reduce consumption of the electrolytes and additives.

25 ENERGY STORAGE↗
DOE OSTI2025

Emergent properties of magnons coupled to microwave photons (Final Technical Report)

Studying the emergent properties of hybrid quantum material platforms holds great promise for advancing quantum technologies and transforming our ability to control quantum mechanical interactions. A key development in recent years is the recognition that magnons – the elementary quanta of spin waves – can serve as fundamental building blocks in quantum systems. Understanding the mechanisms behind the generation and control of hybrid quasiparticles based on magnons could pave the way for engineering new materials for quantum coherent processing and quantum computing. This research project focused on the precise control of light-matter interactions in magnetic hybrid systems and nanostructures, where light is carried by microwave photons and matter by magnons in engineered magnetic metamaterials. Furthermore, we investigated hybridized magnon interactions in magnetic nanostructures and devices. To this end, the project has developed new measurement techniques and systematically studied novel material systems for efficient magnon-photon coupling. A key focus was uncovering the fundamental mechanisms governing magnon-photon and magnon-phonon interactions – critical for utilizing magnons as coherent information transducers between carriers. Specifically, this research addressed: 1. Investigate the dispersion and collective properties of magnon hybrid systems in new material systems. 2. Develop magnonic hybrids with non-zero wavevectors and achieve effective control of magnon-polariton properties through engineered magnonic behaviors. 3. Determine how spin-orbit torques interact with electromagnetic fields in the strong coupling regime. This work generated new insights into the physics of magnonic hybrid systems and their emergent properties by broadening the range of material platforms and measurement techniques used to study magnon-photon and magnon-magnon coupling. The findings deepen our understanding of magnon-polaritons and lay the groundwork for novel spintronic devices with potential applications in quantum information science.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
NASA NTRS1993

Simulated space environmental effects on a polyetherimide and its carbon fiber-reinforced composites

The selection of materials for spacecraft construction requires identification of candidate materials which can perform reliably in the space environment. Understanding the effects of the space environment on the materials is an important step in the selection of candidate materials. This work examines the effects of energetic electrons, thermal cycling, electron radiation in conjunction with thermal cycling, and atomic oxygen on a thermoplastic polyetherimide and its carbon-fiber-reinforced composites. Composite materials made with non-sized fibers as well as materials made with fibers sized with an epoxy were evaluated. The mechanical and thermomechanical properties of the materials were studied and spectroscopic techniques were used to investigate the mechanisms for the observed effects. Considerations for future material development are suggested.

Kern, Kristen T.↗
NASA NTRS1972

An ESCA study of lunar and terrestrial materials.

The technique of electron spectroscopy for chemical analysis (ESCA) is used to obtain rapid, nondestructive elemental analyses of selected lunar samples, and the chemical shift of the Fe(2p) line in lunar materials is found characteristic of iron in the Fe(2+) state. A difference in binding energy of approximately 0.5 eV is observed between the 0(1s) levels of the terrestrial minerals fayalite and quartz, and effects due to surface oxidation and absorption are also observed in terrestrial materials. The new ESCA technique is based on energy analysis at high resolution of electrons emitted from the surface of a sample on irradiation with X rays and is valuable for the study of the electronic structure of atoms and molecules.

Huntress, W. T., Jr.↗
DOE OSTI2024

Computational Exploration of High Entropy Alloys as Promising Materials for Future Beam Windows

With the ever-increasing demand for high beam power, the currently used beam-intercepting devices (BIDs) such as targets, and beam windows may not be able to handle the high power required for future accelerator complexes or the lifetime may be reduced drastically. As beam power increases, the damage incurred by BIDs, including thermal shock, fatigue, and irradiation damage, also rises. Therefore, it is imperative to design materials that can withstand high beam power for longer lifetimes. High entropy alloys (HEAs) have emerged as potential alternative materials for designing next-generation BIDs. In this study, we primarily focus on materials for developing beam windows for next-generation accelerator complexes. We propose an integrated approach that combines various computational techniques to study and design new materials. Specifically, we use CALPHAD, density functional theory (DFT), and molecular dynamics (MD) to comprehensively investigate the defect properties of suitable HEAs, offering potential alternatives for future beam windows. We begin by scanning the extensive phase space provided by Cr-Mn-V-Ti-Al-Co HEAs, selecting 8 compositions after evaluating approximately 120,000 unique compositions using CALPHAD. We, then employ DFT-informed machine learning techniques to develop force-field parameters. Finally, MD simulations using these developed force-field parameters will be used to study the effects of radiation damage on the defect and mechanical properties of the selected alloys. This research explains the use of the CALPHAD approach and shows how critical modeling (DFT and MD) is in developing novel material such as HEAs. It also highlights the promising role of machine learning in this field. The results from this study will greatly improve the novel materials development to be used in next-generation accelerator components, leading to higher beam power and longer operational times of BIDs.

43 PARTICLE ACCELERATORS↗
NASA NTRS2002

Presolar/Interstellar Materials

This talk will review much of our current understanding of the origins, nature, and evolution of materials in circumstellar and interstellar space. I will begin by familiarizing the audience with some of the nomenclature associated the field, reviewing the lifecycle of dust in space, and pointing out where the speakers that follow will address portions of the lifecycle in greater detail. I will then address the different techniques used to study interstellar materials, paying particular attention to (i) telescopic remote sensing of the dust currently in interstellar space, (ii) laboratory studies of individual interstellar grains found in meteorites and other extraterrestrial materials, and (iii) laboratory simulation experiments. To complete the talk, I will focus on the nature of interstellar organic compounds as a particular example of how these disparate techniques can be used to improve our understanding of interstellar matter. While interstellar organics will be addressed in general, particular attention will be made to that portion of the organic inventory that may play a role in the origin and evolution of life on planetary surfaces.

Sandford, Scott A.↗
NASA NTRS1981

Application of remote sensing to monitoring and studying dispersion in ocean dumping

Remotely sensed wide area synoptic data provides information on ocean dumping that is not readily available by other means. A qualitative approach has been used to map features, such as river plumes. Results of quantitative analyses have been used to develop maps showing quantitative distributions of one or more water quality parameters, such as suspended solids or chlorophyll a. Joint NASA/NOAA experiments have been conducted at designated dump areas in the U.S. coastal zones to determine the applicability of aircraft remote sensing systems to map plumes resulting from ocean dumping of sewage sludge and industrial wastes. A second objective is related to the evaluation of previously developed quantitative analysis techniques for studying dispersion of materials in these plumes. It was found that plumes resulting from dumping of four waste materials have distinctive spectral characteristics. The development of a technology for use in a routine monitoring system, based on remote sensing techniques, is discussed.

Johnson, R. W.↗
DOE OSTI2020

Crystallography of low Z material at ultrahigh pressure: Case study on solid hydrogen

Diamond anvil cell techniques have been improved to allow access to the multimegabar ultrahigh-pressure region for exploring novel phenomena in condensed matter. However, the only way to determine crystal structures of materials above 100 GPa, namely, X-ray diffraction (XRD), especially for low Z materials, remains nontrivial in the ultrahigh-pressure region, even with the availability of brilliant synchrotron X-ray sources. In this work,we perform a systematic study, choosing hydrogen (the lowest X-ray scatterer) as the subject, to understand how to better perform XRD measurements of low Z materials at multimegabar pressures. The techniques that we have developed have been proved to be effective in measuring the crystal structure of solid hydrogen up to 254 GPa at room temperature [C. Ji et al.,Nature 573, 558–562 (2019)]. We present our discoveries and experiences with regard to several aspects of this work, namely, diamond anvil selection, sample configuration for ultrahigh-pressure XRD studies,XRD diagnostics for low Z materials, and related issues in data interpretation and pressure calibration.We believe that these methods can be readily extended to other low Z materials and can pave the way for studying the crystal structure of hydrogen at higher pressures, eventually testing structural models of metallic hydrogen.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Chapter 10.02 - Neutron Scattering Studies of Materials for Hydrogen Storage

Hydrogen storage presents a significant barrier to the widespread adaptation of hydrogen as an energy source in mobile and stationary applications. The development of new candidate hydrogen storage materials is therefore an outstanding goal in the field of inorganic chemistry. Neutron scattering techniques - including diffraction, inelastic, and quasielastic scattering - are integral in investigating these materials. Here, we review some of the key studies of candidate hydrogen storage materials which have employed neutron scattering techniques. We begin with a brief discussion of hydrogen's current position in the global energy landscape. Next, we provide a brief description of the theory and practical aspects of the neutron scattering techniques germane to the study of hydrogen storage. Then we enumerate the neutron scattering studies of candidate hydrogen storage materials, including metal hydrides, chemical hydrides, and porous compounds. We focus on the studies which helped develop our understanding of hydrogen storage by revealing the underlying fundamental physics and chemistry of hydrogen sorption in these systems. Finally, we provide an outlook to the future of hydrogen storage research.

chemical hydrides↗
DOE OSTI2021

Ab initio molecular dynamics on quantum computers

Ab initio molecular dynamics (AIMD) is a valuable technique for studying molecules and materials at finite temperatures where the nuclei evolve on potential energy surfaces obtained from accurate electronic structure calculations. In this work, we present an approach to running AIMD simulations on noisy intermediate-scale quantum (NISQ)-era quantum computers. The electronic energies are calculated on a quantum computer using the variational quantum eigensolver (VQE) method. Algorithms for computation of analytical gradients entirely on a quantum computer require quantum fault-tolerant hardware, which is beyond NISQ-era. Therefore, we compute the energy gradients numerically using finite differences, the Hellmann-Feynman theorem, and a correlated sampling technique. This method only requires additional classical calculations of electron integrals for each degree of freedom without any additional computations on a quantum computer beyond the initial VQE run. As a proof of concept, AIMD simulations are demonstrated for the H-2 molecule on IBM quantum devices. In addition, we demonstrate the validity of the method for larger molecules using full configuration interaction wave functions. As quantum hardware and noise mitigation techniques continue to improve, the method can be utilized for studying larger molecular systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1994

Heating And Positioning In A Microwave Cavity

Two reports describe theoretical and experimental studies of microwave dielectrophoretic positioning of spherical sample of lossy dielectric material in microwave resonant cavity and heating of positioned sphere by electro-magnetic field. Studies part of continuing effort to develop techniques for containerless processing of materials in microgravity. Previous studies in this series described in "Microwave Dielectrophoretic Levitation in Microgravity" (NPO-18824).

Jackson, Henry W.↗
NASA NTRS1989

A study of the stress wave factor technique for evaluation of composite materials

The acousto-ultrasonic approach for nondestructive evaluation provides a measurement procedure for quantifying the integrated effect of globally distributed damage characteristic of fiber reinforced composite materials. The evaluation procedure provides a stress wave factor that correlates closely with several material performance parameters. The procedure was investigated for a variety of materials including advanced composites, hybrid structure bonds, adhesive bonds, wood products, and wire rope. The research program focused primarily on development of fundamental understanding and applications advancements of acousto-ultrasonics for materials characterization. This involves characterization of materials for which detection, location, and identification of imperfections cannot at present be analyzed satisfactorily with mechanical performance prediction models. In addition to presenting definitive studies on application potentials, the understanding of the acousto-ultrasonic method as applied to advanced composites is reviewed.

Duke, J. C., Jr.↗
DOE OSTI2025

CASM Monte Carlo: Calculations of the thermodynamic and kinetic properties of complex multicomponent crystals

Monte Carlo techniques play a central role in statistical mechanics approaches that connect macroscopic thermodynamic and kinetic properties to the electronic structure of a material. This paper describes the implementation of Monte Carlo techniques for the study of multicomponent crystalline materials within the Clusters Approach to Statistical Mechanics (CASM) software suite, and demonstrates their use in model systems to calculate free energies and kinetic coefficients, study phase transitions, and construct phase diagrams from first principles. Many crystal structures are complex, with multiple sublattices occupied by differing sets of chemical species, along with the presence of vacancies or interstitial species. This imposes constraints on concentration variables, the form of thermodynamic potentials, and the values of kinetic transport coefficients. The framework used by CASM to formulate thermodynamic potentials and kinetic transport coefficients accounting for arbitrarily complex crystal structures is presented and demonstrated with examples of increasing complexity. Additionally, an overview of the capabilities of the CASM software specific to Monte Carlo methods is given, and a new CASM software package is introduced, casm-flow, which helps automate the setup, submission, management, and analysis of Monte Carlo simulations.

Cluster expansion↗
NASA NTRS1961

Electron and Light Microscopy Techniques Suitable for Studying Fatigue Damage in a Crystallized Glass Ceramic

The crystals of Pyroceram are randomly oriented and highly reflective so that standard microscopy techniques are not satisfactory for studying this material. Standard replicating procedures proved difficult to use. New microscopy techniques and procedures have therefore been developed. A method for locating, orienting, and identifying specific areas to be viewed with an electron microscope is described. This method not require any special equipment. Plastic replicas were found to be unsatisfactory because of their tendency to adhere to Pryoceram. This caused them to tear when released or resulted in artifacts. Preshadowed silicon monoxide replicas were satisfactory but required a releasing agent. A method of depositing the releasing agent is described. To polish specimens without evidence of fire-polishing, it was found necessary to use a vibratory polishing technique. Chrome oxide was used as the abrasive and either water or kerosene as the lubricant. Vibratory polishing is extremely slow, but surfaces so polished show no evidence of fire polishing, even when examined by electron microscopy. The most satisfactory etching process used for Pyroceram 9608 consisted of a primary etch of 5 milliliters of hydrochloric acid (concentrated), 5 milliliters of hydrogen fluoride (45 percent), and 45 milliliters of water, and a secondary etch with methyl alcohol replacing the water. Best results were obtained with total etching times from 25 to 30 seconds. Staining of the Pyroceram surface with a Sanford's marker was found to be an expedient way to reduce the glare of reflected light.

Harrell, Shelley↗