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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Structural and Magnetic Properties of La-Substituted M-Type Hexagonal Sr–Ni Ferrites Synthesized by Ball-Milling-Assisted Ceramic Process

Sr{sub 0.5}Ni{sub 0.5}La{sub x}Fe{sub 12 − x}O{sub 19} (x = 0, 0.08, 0.16, and 0.24) hexaferrites have been synthesized by ball-milling-assisted ceramic process. The calcined samples are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and vibrating sample magnetometry (VSM). XRD reveals that all samples consist of the main M-type hexagonal Sr ferrite phase and a low amount of rhombohedral Fe{sub 2}O{sub 3} as secondary phase, and a continuous increase of the hexagonal lattice parameters with substitution content (x). Magnetic characterization indicates that all Sr{sub 0.5}Ni{sub 0.5}La{sub x}Fe{sub 12 − x}O{sub 19} samples have a hard magnetic property. Substitution of Fe{sup 3+} ions by La{sup 3+} ions can obviously improve the specific saturation magnetization, remanence, magnetic moment, and effective anisotropy constant. Specific saturation magnetization, remanence, and the magnetic moment reach a maximum at x= 0.24 and calcination temperature of 1050 {sup ∘}C.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Structural, Morphological, Raman, and Mössbauer Studies on (La{sub 0.8}Ca{sub 0.2}){sub 1−x}Bi{sub x}FeO{sub 3} (x = 0.0, 0.1, and 0.2) Compounds

(La{sub 0.8}Ca{sub 0.2}){sub 1−x}Bi{sub x}FeO{sub 3} (x = 0.0, 0.1, and 0.2) compounds were prepared by the sol-gel method, using the citric acid route. Structural and microstructural characteristics of the samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. Mössbauer spectroscopy was also used for magnetic characterization and structural confirmation of X-ray data. Refinement of XRD patterns indicated that the compounds crystallize in an orthorhombic structure, Pnma space group. The SEM measurements showed that the morphology of the samples is characterized by the existence of large agglomerates, while TEM confirmed the fine particle size. Raman spectra revealed that, when increasing temperature, the level of oxygen species adsorbed at the surface of the particles increases progressively. Room temperature Mössbauer spectroscopy data revealed the existence of two octahedral magnetic sites in the structure of the compounds, which is compatible with XRD data, and a small percentage of a paramagnetic phase in the samples, which increases with Bi-content.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Structural and optical properties of ZnO thin films grown by rapid atmospheric mist chemical vapor technique

In this work, the effect of deposition time on the structural and optical properties of ZnO films deposited by Ultrasonic Spray Mist-CVD was studied aiming the application in perovskite solar cells, as holes blocking layer. Crystallinity, surface morphology and optical properties of the ZnO films were investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), conventional and Photoluminescence (PL) spectroscopies, respectively. The XRD measurement proves the existence of the hexagonal wurtzite phase and a high degree of crystallinity with [001] preferential orientation. The SEM study shows that the films possess a compact structure. Smooth and homogenous surface was confirmed also by AFM. The obtained results indicate that ZnO films deposited by a simple, safe and cost-effective method present a great potential for application in perovskite solar cells.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2019

Composition dependence of structural and optical properties of Ge{sub x}Se{sub 100−x} semiconducting thin films

The studied thin films of Ge{sub x}Se{sub 100−x} compositions were synthesized with thermal evaporation technique at room temperature. The effect of composition on the structure of the prepared films was characterized by X-ray diffraction and scanning electron microscopy. The stoichiometry of the studied compositions was examined by energy dispersive X-ray spectroscopy. The film thickness and refractive index were calculated by Swanepoel’s method. The structural analysis showed that the as-prepared Ge{sub x}Se{sub 100−x} (x = 10, 15, 20 and 30 at.%) films exhibit the amorphous state while other films containing 25, 35 and 40 at.% of Ge are polycrystalline. On the other hand, the GeSe and Se crystalline phases are obtained for the annealed films. The analysis of the optical spectra showed that E{sub g} increases with increasing Ge content up to a x = 30 at.% and then decreases with further increase of the Ge concentration. Other many optical parameters such as optical conductivity, dispersion energy and dissipation factor were determined and strongly affected by the variation of the composition.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

To study the effect of doping concentration of silver on structural and optical properties of cadmium oxide (CdO) nanostructure

The present work deals with study of structural and optical properties of Silver (Ag) doped Cadmium oxide (CdO) nanostructured synthesized by Chemical Co-precipitation Techniques followed by calcinations at small temperature. The doping concentrations were changing from 0.1 to 10 at% respectively. Structural analysis study of these calcined materials is carried out by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The optical properties of calcined samples were investigating by Fourier transformation infrared (FTIR)spectroscopy, UV-Visible Spectroscopy (UV-Vis). The structural properties analysis results revels that crystallite size are in the range of nano region and TEM results are quite in accordance with XRD results.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2018

Preparation of Nanosized Tungsten and Tungsten Oxide Powders

Nanopowder tungsten oxide and metallic tungsten are obtained via pyrolysis of ammonium metatungstate. Two methods are used for the synthesis of tungsten oxide: the use of a fibrous matrix and pyrolysis of aerosol particles. Tungsten oxide particles are formed during the pyrolysis in air. Metallic tungsten nanoparticles are obtained via subsequent thermal reduction of tungsten oxide in hydrogen. The structure and morphology of the samples are studied with X-ray diffraction and scanning electron microscopy. Tungsten nanopowders with average sizes from 7 to 30 nm are obtained depending on synthesis temperature. The electrochemical characteristics of electrodes coated with tungsten nanoparticles are studied with cyclic voltammetry, impedance spectroscopy, and galvanostatic charge–discharge methods. An electrode with W nanoparticles exhibited a specific low-frequency capacitance of about 90 F/g due to thin tungsten oxide film on the surface of tungsten nanoparticles.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Synthesis of Bismuth Functionalized Grapheme Oxide for Radioactive Iodine Gas Removal - 16114

Released radioactive iodine from nuclear reactors and nuclear severe accidents, such as those experienced at Chernobyl and Fukushima, is one of the most hazardous materials and can affect human health. Uptake of radioactive iodine from gaseous and aqueous waste, consisting of mainly organic forms such as methyl iodide and elemental iodine after reacting with organic matter in scrubber process, is a recent concern during nuclear power plant operation. In general, Triethylenediamine (TEDA) or KI-impregnated activated carbons, silver-loaded silica aerogels, and silver-loaded zeolite are used to remove radioactive iodine compounds. However, previous research has shown TEDA and KI-impregnated activated carbons to have some limitations for use in responding to severe accidents or in pressurized-water reactors, because they are easily burned up and the iodine removal efficiency of silver-loaded sorbents is greatly decreased at high temperatures. To improve the capability of synthesized sorbent material used in iodine gas removal, highly efficient sorbents for methyl and elemental iodine removal were prepared through the functionalization of graphene oxide (GO) with bismuth. GO was synthesized from natural graphite powder (99.95%) by the modified Hummers method, and then mixed with Bi(NO{sub 3}){sub 3}.5H{sub 2}O. After developing a sorbent for the removal of iodine, the synthesized sorbent was characterized using x-ray diffraction, a scanning electron microscope/energy dispersive spectrometer, and thermogravimetric analysis/differential scanning calorimetry, and the surface area of sorbents was determined using the BET-N{sub 2} adsorption method. Methyl iodine batch experiments were conducted for 7 days and elemental iodine gas adsorption experiments were conducted at high temperature (190 deg. C) using a carrier gas (air). The final concentration of iodine in batch and off-gas scrubber solutions (0.1 M NaOH) was analyzed using inductively coupled plasma mass spectrometry. The breakthrough curve and decontamination factor values were also investigated using bismuth-functionalized GO and the results were compared with Ag-zeolite, Sn-apatite, and activated carbon. (authors)

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2018

Realization of strong violet and blue emissions from ZnO thin films by incorporation of Cu ions

Highlights: • A strong blue-violet co-emission occurs after Cu ions are doped into ZnO thin films.. • The violet emission centered at 430 nm is attributed to transitions of electrons from conduction band to Cu{sup +} acceptor levels. • The blue emission centered at 470 nm is attributed to transitions of electrons from Cu{sup 2+} donor levels to Cu{sup +} acceptor levels. • Both the violet and blue emissions decrease when Cu-doping concentration is higher than 2 at.%. - Abstract: In recent years, Cu-doped ZnO materials have attracted wide attention due to some unique properties, such as p-type conduction, room-temperature ferromagnetism and plentiful luminescence behavior. In this work, Cu-doped ZnO thin films with different doping levels were prepared by sol–gel method. The structural, morphological features and the composition of the samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX), respectively. The optical properties were analyzed by the UV–visible transmittance spectra and fluorescence spectra. The Cu-doping in a low concentration does not influence the crystal phase of wurtzite ZnO and has a very small impact on c-axis preferred orientation of ZnO thin films. With the increase of Cu-doping concentration, the Cu ions are gradually changed from dominant Cu{sup +} ions to dominant Cu{sup 2+} ions. Cu-doping in a low concentration caused strong blue-violet emissions in ZnO thin films. The violet emission is attributed to the transition of electrons from the conduction band to Cu{sup +} acceptor levels, and the blue emission is ascribed to the transition of electrons from Cu{sup 2+} donor levels to Cu{sup +} acceptor levels.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2017

Preparation and Characterization of Magnetite–Chitosan Nanoparticles and Evaluation of Their Cytotoxicity Effects on MCF7 and Fibroblast Cells

Nowadays, magnetic nanoparticles play a key role in drug treatment. However, if they are uncoated, they might aggregate and cause embolism in drug delivery. To avoid this, they are generally coated with polymers. In this investigation, magnetic nanoparticles (MNPs) were coated with chitosan through in situ co-precipitation process and their properties in addition to their cytotoxicity in MCF7 and fibroblast cells were analyzed. The results showed MNPs–chitosan nanoparticles would contain an average mean diameter of 32 nm and a saturation magnetization (M{sub S}) value of 38.87 emu/g. To characterize the synthesized nanoparticles in terms of structural, morphological and magnetic properties, Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA) and vibrating sample magnetometry (VSM) studies were used. Toxicity test was also done to investigate whether their presence would cause any toxicity in the body; in addition, antibacterial assay was done to analyze if nanoparticles could be used as an antimicrobial agent.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Preparation of RE(DBM){sub 3}·Phen (RE=Eu{sup 3+},Tb{sup 3+}) Plate-Loading Fe{sub 3}O{sub 4} Nanospheres and their Magnetic-Optic Bifunctional Property

A facile wet chemical method has been used to synthesize bifunctional core-shell nanoparticles of Fe{sub 3}O{sub 4}@RE(DBM){sub 3}·Phen (RE=Eu{sup 3+},Tb{sup 3+}) showing an interesting combination of magnetic and luminescent properties. This method is convenient, cheap, and efficient. The morphology, structure, luminescent, and magnetic properties of the nanoparticles were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis absorption, fluorescence emission, and superconducting quantum interference device magnetometer (SQUID-VSM). The maximum emission peaks of novel Eu{sup 3+} and Tb{sup 3+} nanocomposites are at 618 nm and at 514 nm, respectively. And their corresponding special saturation magnetization Ms. are 25.853 emu/g and 24.015 emu/g, respectively. For the nanoparticles, it is shown that there have better magnetic behavior and they may act as red- and green-emitting material with potential application for fluorescent magnetic particle testing. Moreover, this chemical route could be used to obtain the development of several bifunctional systems of other rare earth ions for practical application.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2019

Silicon Production via Reaction of Silicon Tetrachloride and Aluminum Subchloride

Silicon tetrachloride reduction by aluminum subchloride was studied experimentally. Aluminum subchloride was synthesized in a reaction of metallic aluminum and AlCl{sub 3}; a burner-like construction of the reactor was used to avoid the direct reaction of aluminum and SiCl{sub 4}. The reduction was conducted at a pressure of 0.1 MPa and two temperature regimes: 1273 K and 1373 K (1000 °C and 1100 °C). As a result, two types of products were obtained: crystals and fine particles. The crystals formation occurred in the high-temperature zone, whereas the particles were dispersed by argon flow and concentrated mainly in aluminum chloride by-product in the cold part of the reactor. It was shown that silicon yield increased with increasing AlCl concentration. The temperature of the reduction process did not have a significant effect on the ultimate silicon yield. However, the silicon etching reaction rate and fine particles yield increased as temperature increased. X-ray diffraction and scanning electron microscopy analysis showed that the impurities content in silicon crystals was below the detection limit. In contrast, the aluminum content in the powder product was 2 to 3 wt pct. Another type of product, yellow blanket-like silicon fibers, was obtained with a high yield at 1373 K (1100 °C) and low [AlCl]:[SiCl{sub 4}] ratio.

36 MATERIALS SCIENCE↗
DOE OSTI2018

The Mechanical and Microstructural Changes of Sn-Ag-Bi Solders with Cooling Rate and Bi Content Variations

The purpose of this study is to investigate the influence of cooling rate and Bi addition on the microstructure evolution and mechanical properties of Sn-3.5Ag alloy. A series of Sn-3.5Ag-xBi solders has been fabricated with Bi content in the range of 0.5-3.5 wt.%. After solution heat treatment at 170 °C for 24 h and subsequent aging heat treatment at 100 °C for 2 h, samples were divided into two groups. One group was rapidly quenched into iced water (water quenching) for the fast cooling rate (20 °C/s), while the second group was slowly cooled (furnace cooling) in the furnace for the slow cooling rate (0.2 °C/s) after the furnace reflow. The microstructural evolutions of the present solders have been investigated using x-ray diffraction and scanning electron microscopy. The microhardness was measured to correlate the mechanical properties to alloy compositions and cooling rate. It was found that the microhardness of Sn-3.5Ag-xBi solders increased with increasing cooling rate. The indentation creep curves have been evaluated from the obtained microhardness values. Results revealed the steady-state creep rate decreased with increasing Bi content exhibiting an anomalous behavior at 2.5Bi. The reason for improved creep resistance of Sn-3.5Ag-xBi solders is the result of the combination of the solid solution strengthening and precipitation strengthening of Bi. The mean values of stress exponent indicated that the operative creep mechanism is dislocation climb.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Silanization of boron nitride nanosheets (BNNSs) through microfluidization and their use for producing thermally conductive and electrically insulating polymer nanocomposites

Chemical exfoliation of boron nitride nanosheets (BNNSs) from large flakes of specially synthesized micro-sized hexagonal boron nitride (h-BN) ceramics was carried out through microfluidization. The surface of BNNSs obtained was then functionalized with vinyl-trimethoxy silane (VTS) coupling agent through microfluidization once again in an effort to make them compatible with organic materials, especially those including polymers. The morphology of BNNSs with and without silane treatment was then systematically characterized by conducting various different analytical techniques, including Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Bright field Transmission Electron Microscopy (BF-TEM), Contact angle analyzer (CAA), Particle size analyzer (PSA) and Fourier Transmission Infrared (FTIR) spectroscopy attached with attenuated total reflectance (ATR) module. As a result, the silane treatment was determined to be properly and successfully carried out and to give rise to the irregularity of large flakes of the BNNSs by folding back their free edges upon themselves, which in turn assists in inducing further exfoliation of the few-layered nanosheets. To gain more insight into the effectiveness of the surface functionalization, thermal conductivity of polypropylene (PP) nanocomposites containing different amounts (1 wt% and 5 wt%) of BNNSs with and without silane treatment was experimentally investigated. Regardless of the weight content, PP nanocomposites containing silanized BNNSs were found to exhibit high thermal conductivity compared to PP nanocomposites containing BNNSs without silane treatment. It was concluded that microfluidization possesses the robustness to provide a reliable product quality, whether in small or large quantities, in a very time effective manner, when it comes to first exfoliating two-dimensional inorganic materials into few layered sheets, and functionalizing the surface of these sheets afterwards to make it possible to utilize them as promising filler constituent in manufacturing thermally conductive and electrically insulating polymer nanocomposites that could be considered as whole or a part of a heat-releasing device.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

A novel fabrication of Cu{sub 2}O@Cu{sub 7}S{sub 4} core-shell micro/nanocrystals from Cu{sub 2}O temples and enhanced photocatalytic activities

Highlights: • The Cu{sub 2}O@Cu{sub 7}S{sub 4} core-shell crystals maintained the same morphology with template. • The crystals exhibit enhanced photocatalytic activity than the pure Cu{sub 2}O crystals. • The photocatalytic activity of different R crystals is diverse from each other. • A possible formation mechanism has been proposed. - Abstract: Uniform and monodispersed Cu{sub 2}O@Cu{sub 7}S{sub 4} core-shell micro/nanocrystals have been synthesized successfully at room temperature via a simple chemical etching reaction, using Cu{sub 2}O as sacrificial template. The structure and properties of the crystals were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS). The photocatalytic activity of the Cu{sub 2}O@Cu{sub 7}S{sub 4} crystals was evaluated by photocatalytic decolorization of MeO (methyl orange) aqueous solution at ambient temperature under visible-light irradiation. The results show that the as-prepared Cu{sub 2}O@Cu{sub 7}S{sub 4} crystals revealed core-shell structure, which maintained the same morphology with corresponding template and were composed of cuboctahedron Cu{sub 7}S{sub 4} shell and active Cu{sub 2}O core. Due to the unique Cu{sub 2}O@Cu{sub 7}S{sub 4} core-shell structure, the crystals exhibit enhanced photocatalytic activity than that of the pure Cu{sub 2}O crystals, and the photocatalytic activity of different R crystals is diverse from each other. A possible formation mechanism has been proposed.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Plasmonic Ag/Ag2O nanoparticles anchored needle-like Bi2O3 as an efficient visible-light-driven nanocomposite photocatalyst

Highlights: • Deposition of plasmonic Ag/Ag{sub 2}O NPs on the surface of Bi{sub 2}O{sub 3}. • Synthesis of Ag/Ag{sub 2}O@Bi{sub 2}O{sub 3} by thermal-assisted precipitation. • SPR of Ag enhances use of solar energy and transfer of carriers. • Degradation of Reactive Black 5 by CCD model. - Abstract: In this study, a thermal-assisted precipitation method was applied for the uniform deposition of plasmonic Ag/Ag{sub 2}O nanoparticles on the surface of needle-like Bi{sub 2}O{sub 3} to synthesis Ag/Ag{sub 2}O@Bi{sub 2}O{sub 3} nanocomposite. The synthesized nanocomposite was characterized by different techniques including UV–vis spectrophotometry, X-ray diffraction (XRD), scanning electronic microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray mapping, and photoluminescence (PL). The visible-light-driven photocatalytic activities of Ag{sub 2}O@Bi{sub 2}O{sub 3} and Ag/Ag{sub 2}O@Bi{sub 2}O{sub 3} were evaluated on photo-degradation of Reactive Black 5 (RB 5) dye as model pollutant. The effect of process variables including the initial dye concentration, reaction time, and pH on the photo-degradation of RB 5 was studied by Central Composite Design (CCD) methodology. It was found that the photo-degradation rate of Ag/Ag{sub 2}O@Bi{sub 2}O{sub 3} was higher than that of the Ag{sub 2}O@Bi{sub 2}O{sub 3} and Bi{sub 2}O{sub 3}. The highly efficient photocatalytic activity of Ag/Ag{sub 2}O@Bi{sub 2}O{sub 3} nanocomposite is mainly ascribed to enhancing photogenerated electron-hole separation and the surface plasmon resonance (SPR) influence of silver-based nanoparticles.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Nanostructuring on zinc phthalocyanine thin films for single-junction organic solar cells

Vertically aligned and random oriented crystalline molecular nanorods of organic semiconducting Zinc Phthalocyanine (ZnPc) have been grown on ITO coated glass substrate using solvent volatilization method. Interesting changes in surface morphology were observed under different solvent treatment. Vertically aligned nanorods of ZnPc thin film were observed in the films treated with acetone, where as the random oriented nanorods were observed in the films treated with chloroform. The X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) have been used for characterization of nanostructures. The optical properties of the nanorods have been investigated by UV-Vis. absorption spectroscopy.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Study of magneto-optic effect on Mn{sub 1-x}Zn{sub x}Fe{sub 2}O{sub 4} nanoferrofluids

Mn{sub 1-x}Zn{sub x}Fe{sub 2}O{sub 4} nanoparticles (with x varying as 0.1, 0.3, 0.5, 0.7 and 0.9) have been synthesized by co- precipitation method using polyvinyl alcohol as surfactant. Structural analysis and surface morphology of the samples were analysed using X-ray diffraction and scanning electron microscope respectively. The Scherer approximation was used to obtain crystallite sizes and found to decrease from 8.9 nm to 4.3 nm with increase in zinc substitution. The chemical composition of samples obtained through EDAX was comparable with the initial substitutions. Saturation magnetization (M{sub s}), Remanence (M{sub r}) and Coercivity (H{sub c}) were measured using VSM at room temperature and found to decrease with increase in zinc substitution. Verdet constant of the samples are obtained from Faraday rotation for various magnetic fields and it varies from 18 × 10{sup −4} to 3 × 10{sup −4}deg/Gcm with zinc substitution.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Characterization of Simulated BWR and Steam Exposed FeCrAl Coated Zircaloy 2

To combat the rapid oxidation that occurs in nuclear reactors during transient scenarios, investigations into modifying or replacing the existing zirconium based cladding and structural material have become a focus. Aside from testing these alternatives in the transient scenarios, verification of performance under normal operation is necessary. This work will examine the effect of normal BWR water chemistry over two time periods on FeCrAl coated Zircaloy 2 (Zry2) and its response to high temperature steam. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray Spectroscopy (EDS), and Thermogravimetric (TG) analysis are utilized to analyze the chemical and physical changes caused by these exposures. These tests show that under short time periods, normal water chemistry BWR conditions do not adversely change the effectiveness of a FeCrAl coating. A spinel structure was formed using Ni from an external source, however it did not have a major impact on the coatings performance in high temperature steam. Additional autoclave exposures up to 40 hours are ongoing, including coatings which were proton irradiated up to 5 dpa. (authors)

36 MATERIALS SCIENCE↗