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Maricela Lizcano

Publications and source records attributed to Maricela Lizcano.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2024

High Yield Exfoliation of a Sub-Micron Hexagonal Boron Nitride Using a Solvent Free Method

Sodium fluoride (NaF) has been found to be an activation agent in exfoliating a hexagonal boron nitride (hBN) platelet, using solvent free method. The procedure was carried out by enhancing the intercalation of ferric chloride (FeCl3) in an intermediate step, up to 330 °C, followed by removal of the by-product at room temperature. In this research, five additional common salts including lithium fluoride, potassium fluoride, lithium chloride, sodium chloride, and potassium chloride, were examined and compared to NaF for their effectiveness in producing the most exfoliation of a commercially available sub-micron-size hBN. It was found that, all fluoride and chloride salts significantly activated the intercalation of FeCl3 into this hBN. Analyses and characterization from X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscoy revealed NaCl to be one of most effective agents without further heat treatment and the least expensive salt in the intercalating reaction and exfoliation process. The synthetic route of this solvent free method is straightforward with 89% yield and above which can be produced on a large scale.

boron nitride↗
NASA NTRS2022

Novel Processing, Testing and Characterization of Copper/Carbon Nanotube (Cu/CNT) Yarn Composite Conductor

Sustainable electrified aircraft propulsion (EAP) is likely to lead to an increase in the electrical wiring contained within a single aircraft. Since the electrical resistance and mass of copper (Cu) conductors are associated with power losses, it is desirable to design high-conductivity lightweight conductor materials, thus reducing the mass of components like motor windings, low-voltage signal cables, and transmission cables for data and power to improve the overall energy efficiency. This paper describes a unique framework for manufacturing metalized carbon nanotube (CNT) composite conductors, measuring their electrical conductivity and strength, and modeling the overall conductivity and current sharing within such composites. Tensile testing was conducted on the processed composite conductor cables with the use of acoustic emission and electrical resistivity to determine stress-dependent-failure mechanisms while monitoring the electrical conductivity. The average of measured electrical conductivities of annealed Cu/CNT samples from batch 5 was greater than theoretical predictions by 9.8 percent and was also greater than the conductivity of pure annealed Cu by 4.8 percent and had comparable ultimate tensile strengths. Additionally, those Cu/CNT samples provide a 13.5% weight saving over current state of the art copper wires. Theories explaining improved intrinsic conductivity are discussed.

Metalized CNT↗
NASA NTRS2022

Modeling of Electro-Magneto-Thermo-Mechanical Interactions in High Voltage Materials and Structures for Electric Propulsion

The growing interest in developing high-voltage-, high-power-capable electrical components for electric aircraft propulsion requires a more in-depth understanding of their electrical characteristics, critical material responses, and their synergistic influence on the overall performance of the system. A model that can accurately replicate the electrical, magnetic, thermal, and mechanical operating stresses and successfully predict the performance of the components will help engineers optimize the system design for a given airframe and powertrain.

electric propulsion↗
NASA NTRS2021

Development and Characterization of Lightweight Durable Composite Conductor for Cables

Sustainable aviation in the form of electrified propulsion is likely to lead to an increase in the electrical assets contained within a single aircraft. As a result, it is desirable to design light weight conductor materials, thus reducing the payload of components like motor windings, low voltage signal cables, and transmission cables for data and power. One approach involves replacing pure Cu wiring with metalized CNT composites. This paper evaluates a framework for modeling overall conductivity and current sharing within such composites. Processing methods and parameters were refined. Select electroplated samples outperformed pure Cu in conductivity and had comparable ultimate tensile strengths. Tensile strengths are expected to improve with an additional densification step during processing. Acoustic emission data was used to predict the failure mechanism of the composite. Theories explaining improved intrinsic conductivity are discussed, with a focus on chemical and mechanical interactions at the Cu-CNT interface. These include Cu infiltration of CNT crevices, CNT oxidation, activity at defects in CNT walls, and the release of carbide-forming metals from CNT walls. Validating any or all these theories will require further work replicating data, collecting electron micrographs and conducting chemical analyses.

Metalized CNT↗
NASA NTRSDate not supplied

NASA-GRC Research Activities in High Voltage (HV) Electrical Insulation

This presentation gives an overview of recent research activities at NASA Glenn Research Center (GRC). The presentation covers research associated with materials for high voltage aerospace electrical insulation applications.

Aerospace Materials Aerospace electrical insulatio↗
NASA NTRSDate not supplied

NASA-GRC High Voltage Materials Development and Test Capabilities Portfolio

This presentation provides the background information on NASA-GRC high voltage (HV) materials team research efforts towards electrified propulsion systems since 2016 . Additionally, it covers polymer and ceramic filler materials development for HV electrical insulation composites, copper/ carbon nanotube hybrid conductors, modeling efforts, HV test capabilities, and future material processing capabilities.

Boron Nitride↗
NASA NTRSDate not supplied

Forcespun Polymers as Precursors to Boron Nitride Fibers

The need for multifunctional materials in aerospace technologies is currently driving the development of new novel composite materials. Specifically, insulation materials with high thermal conductivity, high electrical resistivity, and are chemically inert are needed for high voltage power applications. Boron nitride (BN) nanomaterials fit these criteria and can be incorporated into composites for further material design. The synthesis of boron nitride through a polymer derived ceramic route allows for the morphology of the resulting BN to be tailored. This is especially beneficial since the polymers can be shaped or spun into fibers prior to the ceramic conversion. This project utilizes the Forcespinning technique to produce boron-containing polymer fibers that are converted to boron nitride through a heat treatment. The chemical compositions and fiber morphologies were studied and reported here.

Boron nitride, Fibers, Forcespinning↗
NASA NTRSDate not supplied

Modification of Hexagonal Boron Nitride with Metal Oxides

The development of multifunctional hexagonal boron nitride (hBN) materials aims to capitalize on the intrinsic properties of hBN which include being electrically insulating, thermally conductive, and chemically and thermally stable at high temperatures. The creation of novel composite materials that include these properties is required to address our current aerospace and space engineering challenges. Researchers at NASA Glenn have done significant prior work which has produced processes to intercalate, exfoliate, coat, and functionalize various hBN materials. This presentation covers our recent progress towards the integration of titanium oxides into hBN utilizing our previous methods along with optimizing and producing new methods to create novel functional hBN nanomaterials.

boron nitride↗
NASA NTRSDate not supplied

Engineered Hexagonal Boron Nitride:Titanium Dioxide Composites for High Voltage Insulation

Hexagonal boron nitride (hBN) and Titanium dioxide are both ceramic materials with widespread use in commercial and consumer applications in everything from cosmetics and paint to deep space satellite components. As a dielectric material, hBN is electrically insulating, thermally conductive, and stable to most temperatures and environments. Titanium dioxide is also a good electrical insulator with a wide bandgap and large dielectric constant, as well as high temperature tolerance and chemical stability. This presentation covers our recent efforts to combine the best properties of hBN and titanium dioxide to produce an intercalated hBN:titanium dioxide composite which was then further processed and incorporated into polymer composites, as well as a standalone ceramic material for testing as a novel insulation material.

boron nitride↗
NASA NTRSDate not supplied

Research Activities in High Voltage (HV) Materials for Aerospace Systems

This presentation gives an overview of recent materials research activities carried out at NASA Glenn Research Center. The background and motivation for the development of thermally conductive electrical insulation for a high voltage (HV) turboelectric aircraft concept is briefly discussed. A summary of the challenges and technology gap associated with HV aerospace electrical systems is also covered as well as the development of electrical insulation and engineered ceramic fillers and HV test capabilities. The research has expanded to include the development of a lightweight copper/ carbon nanotube composite conductor. Applications for these materials include hybrid electric aircraft, all electric aircraft, spacecraft, electric propulsion systems, and future power transmission systems for Lunar and Martian destinations.

Composite conductors↗