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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 1,729 records · Page 96
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Laser gain media fabricated via direct ink writing (DIW) and ceramic processing

A transparent ceramic optic includes: a lasing region comprising at least one lasing species dopant; and a transparent region transparent to light generated by the lasing species. At least the transparent region is doped with at least one other dopant species such that the lasing region and the transparent region are characterized by a difference in refractive index between the two regions in an amount of about 1.0×10−4 or less. Inventive formulations of inks suitable for fabricating transparent ceramic optics having desirable compositional characteristics such as concentration gradients in desired spatial arrangements, e.g. using additive manufacturing techniques such as direct ink writing and/or extrusion freeform fabrication are also disclosed, along with suitable techniques for forming the transparent ceramic optics from such inks.

Payne, Stephen A.↗
DOE OSTI2021

Experimental Fabrication of Porous Additive Manufactured Material

Nuclear industries can benefit from materials that can perform well mechanically and thermally in high temperature and corrosion environments. Functionally graded materials (FGM) are materials manufactured with complex spatial, structural, and chemical compositions, creating components predesigned with tailored microstructural and mechanical properties. Porosity-graded FGMs are designed to introduce pores into a component’s structure as a mechanism to increase bulk or surface material performance, such as stress accommodation and negative thermal conductivity. Additive manufacturing (AM) techniques such as laser energy net shape (LENS) and wire arc additive manufacturing (WAAM), excel in high energy density, point-to-point metal deposition, and present in combination with other combinatorial approaches, exciting methods to manufacture porous FGM components. This project is also examining plasma jet printing as another means for method evaluations for smaller scale graded components. This study explores AM FGM process parameters and combinatorial fabrication methodologies for stainless steel components functionally graded in porosity levels. Preliminary characterization results are provided to attest the feasibility of the combinational fabrication techniques.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Nanowire and micro wire fabrication technique and product

A continuous or semi-continuous process for fabricating nanowires or microwires makes use of the substantially planar template that may be moved through electrochemical solution to grow nanowires or microwires on exposed conductive edges on the surface of that template. The planar template allows fabrication of the template using standard equipment and techniques. Adhesive transfer may be used to remove the wires from the template and in one embodiment to draw a continuous wire from the template to be wound around the drum.

Sumant, Anirudha V.↗
DOE OSTI2021

Alkali semi-metal films and method and apparatus for fabricating them

Methods and systems for fabricating a film, such as, for example, a photocathode, having a tailored band structure and thin-film components that can be tailored for specific applications, such as, for example photocathode having a high quantum efficiency, and simple components fabricated by those methods.

Bhandari, Harish B.↗
DOE OSTI2021

Process for fabrication of enhanced β″-alumina solid electrolytes for energy storage devices and energy applications

A dense β″-alumina/zirconia composite solid electrolyte and process for fabrication are disclosed. The process allows fabrication at temperatures at or below 1600° C. The solid electrolytes include a dense composite matrix of β″-alumina and zirconia, and one or more transition metal oxides that aid the conversion and densification of precursor salts during sintering. The composite solid electrolytes find application in sodium energy storage devices and power-grid systems and devices for energy applications.

Lu, Xiaochuan↗
DOE OSTI2022

Optimizing the Fabrication of Electrospun Nanofibrous Membrane Using Fractional Factorial Design

Electrospinning, a simple and easily tunable technique that utilizes the force balance between the electrostatic force and the solution surface tension to fabricate membranes out of 1D nanostructured fibers, has garnered much interest especially from the nanotechnology community. Depending on the morphology of the fibers, electrospun membrane has found its way in a wide range of applications, such as oil-water separation, desalination, tissue engineering, and batteries. During an electrospinning process, many factors can affect the morphology of the products, such as viscosity of the solution, voltage supply, discharge distance, feed rate of the solution, and electrospinning time. In this work, we investigated the impacts of the most important parameters on the morphology of electrospun fibrous membrane based on the fractional factorial design. We evaluated the electrospun fibrous membrane morphology using scanning electron microscopy (SEM) and capillary flow porometry. Poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was chosen for the current study due to its interesting and versatile functionalities including superior hydrophobicity, high free volume, and piezoelectricity. This work provides valuable insight for the fabrication of electrospun membranes, especially for tailoring membrane properties in accordance with any targeted applications.

Zhao, Yajing↗
DOE OSTI2022

Fabrication experience of the pre-production PIP-II SSR2 cavities at Fermilab

The Proton Improvement Plan-II (PIP-II, [1]) linac will include 35 Single Spoke Resonators type 2 (SSR2). A total of eight pre-production SSR2 jacketed cavities will be procured and five installed in the first pre-production cryomodule. The mechanical design of the jacketed cavity has been finalized and it will be presented in this paper along with fabrication and processing experience. The importance of interfaces, quality controls and procurement aspects in the design phase will be remarked as well as lessons learned during the fabrication process. Furthermore, development studies will be presented together with other design validation tests.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Method for fabricating embedded nanostructures with arbitrary shape

A layered heterostructure, comprising alternating layers of different semiconductors, wherein one of the atom species of one of the semiconductors has a faster diffusion rate along an oxidizing interface than an atom species of the other semiconductor at an oxidizing temperature, can be used to fabricate embedded nanostructures with arbitrary shape. The result of the oxidation will be an embedded nanostructure comprising the semiconductor having slower diffusing atom species surrounded by the semiconductor having the higher diffusing atom species. The method enables the fabrication of low- and multi-dimensional quantum-scale embedded nanostructures, such as quantum dots (QDs), toroids, and ellipsoids.

Wang, George T.↗
DOE OSTI2022

Optical systems fabricated by printing-based assembly

Provided are optical devices and systems fabricated, at least in part, via printing-based assembly and integration of device components. In specific embodiments the present invention provides light emitting systems, light collecting systems, light sensing systems and photovoltaic systems comprising printable semiconductor elements, including large area, high performance macroelectronic devices. Optical systems of the present invention comprise semiconductor elements assembled, organized and/or integrated with other device components via printing techniques that exhibit performance characteristics and functionality comparable to single crystalline semiconductor based devices fabricated using conventional high temperature processing methods. Optical systems of the present invention have device geometries and configurations, such as form factors, component densities, and component positions, accessed by printing that provide a range of useful device functionalities. Optical systems of the present invention include devices and device arrays exhibiting a range of useful physical and mechanical properties including flexibility, shapeability, conformability and stretchablity.

Rogers, John↗
DOE OSTI2023

Challenges and Lessons Learned from fabrication, testing and analysis of eight MQXFA Low Beta Quadrupole magnets for HL-LHC

By the end of October 2022, the US HL-LHC Accelerator Upgrade Project (AUP) had completed fabrication of ten MQXFA magnets and tested eight of them. The MQXFA magnets are the low beta quadrupole magnets to be used in the Q1 and Q3 Inner Triplet elements of the High Luminosity LHC. This AUP effort is shared by BNL, Fermilab, and LBNL, with strand verification tests at NHMFL. An important step of the AUP QA plan is the testing of MQXFA magnets in a vertical cryostat at BNL. The acceptance criteria that could be tested at BNL were all met by the first four production magnets (MQXFA03-MQXFA06). Subsequently, two magnets (MQXFA07 and MQXFA08) did not meet some criteria and were disassembled. Lessons learned during the disassembly of MQXFA07 caused a revision to the assembly specifications that were used for MQXFA10 and subsequent magnets. In this paper, we present a summary of: 1) the fabrication and test data of all the MQXFA magnets; 2) the analysis of MQXFA07/A08 test results with characterization of the limiting mechanism; 3) the outcome of the investigation, including the lessons learned during MQXFA07 disassembly; and 4) the finite element analysis correlating observations with test performance.

43 PARTICLE ACCELERATORS↗
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 OSTI2023

Design and fabrication of the waveguide Iris couplers for the Spallation Neutron Source drift tube linac

The Spallation Neutron Source (SNS) employs six cavities in the Drift Tube Linac (DTL) section to accelerate the H- ion beam to 87MeV. Each cavity is energized by a 2.5MW peak power klystron at 402.5MHz using rapid tapered waveguide iris couplers. All six original iris couplers have been in operation without replacement for over two decades. The increased RF power demands of the Proton Power Upgrade (PPU) project and operational problems, including arcing, temperature excursions, and vacuum bursts, have prompted the development of new iris coupler spares. The original iris couplers were made of GlidCop material, which is known to be mechanically strong and thermally stable, but is porous, expensive, and difficult to use in fabrication. To overcome these problems, the new spare couplers use Oxygen-Free Copper (OFC) and stainless steel (SS). This paper will discuss the mechanical, thermal and RF design, as well as challenges in the final coupler fabrication.

Lee, Sung-Woo↗
DOE OSTI2022

Ultra-high temperature carbide foams and methods of fabricating the same

Ultra-high temperature carbide (UHTC) foams and methods of fabricating and using the same are provided. The UHTC foams are produced in a three-step process, including UHTC slurry preparation, freeze-drying, and spark plasma sintering (SPS). The fabrication methods allow for the production of any kind of single- or multi-component UHTC foam, while also providing flexibility in the shape and size of the UHTC foams to produce near-net-shape components.

Agarwal, Arvind↗
DOE OSTI2023

Method for fabricating a hybrid carbon nanofiber product

Hybrid carbon nanofiber (Cnf) products (e.g., mats, yarns, webs, etc.) and methods of fabricating the same are provided. The hybrid Cnf products are flexible and lightweight and have high thermal conductivity. An electrospinning process can be used to fabricate the hybrid Cnf products and can include preparation of an electrospinning solution, electrospinning, and carbonization (e.g., under a vacuum condition).

Agarwal, Arvind↗
DOE OSTI2013

Parameter survey on heating conditions for glass-bonded sodalite ceramic waste fabrication from type-A zeolite containing simulating FPs

In the pyrometallurgical reprocessing for metal fuel cycle, fission products (FPs) in the spent salt is converted into a glass-bonded sodalite by means of Pressure-less Consolidation (PC). Although a standard condition of the PC method was reported, the reason for choosing this condition is not clear particularly for the temperature condition. In the present study, a parameter survey on the heating condition was performed by fabricating the glass-bonded sodalite containing simulating FPs under various conditions. The maximum temperature, the heating duration, the glass ratio in the initial material, and the weight load for pressing the material were chosen as the variable parameters. The mass balance of each element and the quality of the product were evaluated. It was exhibited that both the volatilized content and the free salt in the product were reduced by lowering the maximum temperature. The apparent density of the product was enhanced by both increasing the heating duration and increasing the weight load. Accordingly, lowering the maximum temperature while increasing the weight load was chosen to modify the fabricating condition. As a result of the modified condition, both the volatilized and the free salt ratios were reduced without significant change in the apparent density of the product. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2023

Small gap device system and method of fabrication

A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Schwede, Jared William↗
DOE OSTI2023

Ultra-high temperature carbide foams and methods of fabricating the same

Ultra-high temperature carbide (UHTC) foams and methods of fabricating and using the same are provided. The UHTC foams are produced in a three-step process, including UHTC slurry preparation, freeze-drying, and spark plasma sintering (SPS). The fabrication methods allow for the production of any kind of single- or multi-component UHTC foam, while also providing flexibility in the shape and size of the UHTC foams to produce near-net-shape components.

Agarwal, Arvind↗