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Results for “condensed matter & materials physics”

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 937 records · Page 52
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Methods of forming structures and fissile fuel materials by additive manufacturing

A method of forming one or more structures by additive manufacturing comprises introducing a first layer of a powder mixture comprising graphite and a fuel on a surface of a substrate. The first layer is at least partially compacted and then exposed to laser radiation to form a first layer of material comprising the fuel dispersed within a graphite matrix material. At least a second layer of the powder mixture is provided over the first layer of material and exposed to laser radiation to form inter-granular bonds between the second layer and the first layer. Related structures and methods of forming one or more structures are also disclosed.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Method and device for using an organic underlayer to enable crystallization of disordered organic thin films

Measurements on organic single crystals reveal remarkable optical and electrical characteristics compared to disordered films but practical device applications require uniform, pinhole-free films. Disclosed herein is a process to reliably convert as-deposited amorphous thin films to ones that are highly crystalline, with grains on the order of hundreds of microns. The disclosed method results in films that are pinhole-free and that possess grains that individually are single crystal domains.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Method for forming perovskite layers using atmospheric pressure plasma

Improved deposition of optoelectronically active perovskite materials is provided with a two step process. In the first step, precursors are deposited on a substrate. In the second step, the deposited precursors are exposed to an atmospheric pressure plasma which efficiently cures the precursors to provide the desired perovskite thin film. The resulting films can have excellent optical properties combined with superior mechanical properties.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Barrier film, method of making the barrier film, and articles including the barrier film

A barrier film that includes a substrate, a first polymer layer on a major surface of the substrate, an oxide layer on the first polymer layer, and a second polymer layer on the oxide layer. At least one of the first or second polymer layers includes a siloxane reaction product of a secondary or tertiary amino-functional silane having at least two silane groups. A method of making the barrier film and articles and a barrier assembly including the barrier film are also disclosed.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Fabrication of films and coatings used to activate shear thickening, impact resistant electrolytes

A method of making a passively impact resistant composite electrolyte and separator layer includes providing a suspension composition including electrically non-conducting particles that enable shear thickening. The particles can have a polydispersity index of no greater than 0.1, an average particle size in a range of from 50 nm to 1 um, and an absolute zeta potential of greater than ±40 mV. A particle suspension solvent is provided for suspending the particles. The suspension composition is applied to a porous separator material. A portion of the particles and suspension solvent penetrate the pores and the remainder of the particles in the suspension composition are distributed across the surface of the separator material. The suspension solvent is evaporated from the separator material to provide a shear thickening particle loaded separator. A separator assembly and a passivated battery are also disclosed.

25 ENERGY STORAGE↗
DOE OSTI2020

Thin-film composite membrane and processes for the separation of alkenes from a gaseous feed mixture

This invention discloses an improved thin-film composite membrane and processes that use the membrane for the separation of gaseous mixtures that include an alkene. The membrane is particularly useful for separation of alkenes from alkanes or the separation of alkenes from other non-hydrocarbon gases. The membrane has a more mechanically durable and defect-free gas-separation layer that is fabricated from an ionomer solution that is substantially free of dissolved ionic species not associated with the ionomer and the mean helium permeability of the thin-film composite membrane is less than two times greater than the intrinsic helium permeability of the gas-separation layer.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Automatic tuning of dressed multicell cavities using pressurized balloons

A method and system for automatically tuning hollow structures, can include pressurized balloons located in one or more targeted cells of a hollow structure of a device having a hollow structures and respective cells. A pressurized balloon can be inserted into a targeted cell so as to localize plastic deformation to the targeted cell using prescribed values of global force and balloon pressure. A pair of inflate/deflate rods associated with an independent air supply for the pressurized balloon can inflate or deflate the pressurized balloon without affecting other pressurized balloons. The pair of inflate/deflate rods can be automatically insertable or removable from the hollow structure by controlled motorized motions.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Passivation and alloying element retention in gas atomized powders

A method for gas atomization of a titanium alloy, nickel alloy, or other alumina (Al2O3)-forming alloy wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a passivation reaction film on the atomized particles wherein the reaction film retains a precursor halogen alloying element that is subsequently introduced into a microstructure formed by subsequent thermally processing of the atomized particles to improve oxidation resistance.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Hybrid semiconductor-piezoacoustic radiofrequency device

An amplifying radiofrequency device includes a piezoelectric film and a semiconductor amplifier layer. The piezoelectric film is conformed as an acoustic waveguide. The piezoelectric film has a principal acoustic propagation direction parallel to the principal conduction direction of the amplifier layer. Interdigitated transducers are positioned on the piezoelectric film to respectively launch an acoustic wave in response to an input RF signal, and transduce the acoustic wave back to an output RF signal. There is a distance of less than the acoustic wavelength between the semiconductor amplifier layer and the piezoelectric film. The piezoelectric film has a thickness of less than the acoustic wavelength. According to a method for making such a device, a stack of III-V layers is epitaxially grown on a III-V substrate, wherein the stack comprises a first etch stop layer, a second etch stop layer, an amplifier layer, and a contact layer. The stack is bonded to a lithium niobate film. The III-V substrate is removed by etching down to the first etch stop layer. Deposition windows are opened by etching from the first etch stop layer down to the contact layer. Metal contact electrodes are deposited in the deposition windows.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Fabricating double-sided electrodynamic screen films

An electrode film is fabricated by using a flexographic printing system to print a first electrode pattern including a first set of parallel electrodes and a second electrode pattern including a second set of parallel electrodes onto a first surface of a transparent film using a catalytic ink, wherein elements of the first electrode pattern do not cross over elements of the second electrode pattern. The flexographic printing system prints a third electrode pattern including a third set of parallel electrodes onto a second surface of the transparent film using the catalytic ink, wherein the first, second and third sets of parallel electrodes are arranged in an interlaced pattern. A conductive metallic material is electrolessly plated onto the catalytic ink such that the elements of the first, second and third electrode patterns become conductive.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Methods and systems for fabricating high quality superconducting tapes

An MOCVD system fabricates high quality superconductor tapes with variable thicknesses. The MOCVD system can include a gas flow chamber between two parallel channels in a housing. A substrate tape is heated and then passed through the MOCVD housing such that the gas flow is perpendicular to the tape's surface. Precursors are injected into the gas flow for deposition on the substrate tape. In this way, superconductor tapes can be fabricated with variable thicknesses, uniform precursor deposition, and high critical current densities.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Methods and systems for fabricating high quality superconducting tapes

An MOCVD system fabricates high quality superconductor tapes with variable thicknesses. The MOCVD system can include a gas flow chamber between two parallel channels in a housing. A substrate tape is heated and then passed through the MOCVD housing such that the gas flow is perpendicular to the tape's surface. Precursors are injected into the gas flow for deposition on the substrate tape. In this way, superconductor tapes can be fabricated with variable thicknesses, uniform precursor deposition, and high critical current densities.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Impact of Irradiation-induced Lattice Defects and Dopants on Thermal Transport in Oxide Nuclear Fuels

Advanced nuclear reactor concepts aim to use fuels that must withstand unprecedented temperature and radiation extremes. In these fuels, thermal energy transport under irradiation is directly related to fuel longevity, reactor safety, and is arguably one of the most important performance metrics. Here we provide a comprehensive, first-principles-informed treatment of phonon mediated thermal transport in a defect-bearing actinide oxide with direct comparison to experimental measurements. Pristine and proton irradiated thorium dioxide was chosen as a model system to treat the complexity of thermal transport in the presence of lattice defects. A thermal transport model is implemented using the linearized Boltzmann transport equation (LBTE) with input from first principles calculations and defect evolution models. The output of the LBTE is compared directly to mesoscopic measurements of thermal conductivity on length scales commensurate with defect accumulation. Parametric measurements of conductivity with irradiation dose and temperature reveal a monotonic decrease in conductivity with irradiation dose, in the range of 0.001 dpa to 0.1 dpa. Besides radiation-induced defects, doping the thorium dioxide crystal with small quantities of uranium atoms also results in a drastic reduction in thermal conductivity. Temperature-dependent measurements of thermal conductivity in uranium-doped thorium dioxide single crystals suggests a resonant scattering mechanism is responsible for the observed reduction. This comprehensive, atomistic- to meso-scale treatment provides the necessary basis to investigate thermal transport under irradiation in more complex systems that exhibit strong electron correlation. This is a poster presentation.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗