Download or read book Vapor deposited Chromium Coatings on Silicon Carbide Fuel Cladding written by Kyle Quillin and published by . This book was released on 2024 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chromium coatings are under investigation to mitigate the hydrothermal corrosion of silicon carbide fiber-reinforced silicon carbide matrix composite (SiC-SiCf) fuel cladding in light water reactors. A variety of direct current magnetron sputtering (DCMS) and high-power impulse magnetron sputtering (HiPIMS) processes were used to deposit Cr coatings 5-10 [mu]m thick on SiC substrates. This research employs multi-scale materials characterization and testing approaches in harsh conditions to understand the scientific phenomena that govern the relationships between the deposition process and coating structure and properties with respect to the important performance considerations necessary for the Cr coatings. Transmission electron microscopy (TEM) revealed that energetic ions produced during HiPIMS deposition improved the coating density compared to DCMS and induced a nanoscale layer of atomic mixing between the Cr coating and SiC substrate. Analysis of the interfacial mixing layer was supported with high resolution chemical analysis and a dynamic Monte Carlo simulation of interfacial compositional evolution during the initial stages of deposition. The effect of thermal exposure on the residual stress state of the Cr coatings was investigated using in situ high temperature X-ray diffraction. It was found that at 300 °C, a coating deposited with bipolar HiPIMS (B-HiPIMS) is under a compressive residual stress, which likely increases the durability of the coating during reactor operation. Through nanoindentation and post-test characterization of indentation pile-up, it was observed that the B-HiPIMS coating deformed in a ductile manner on account of its coarse columnar grain structure and high density, allowing it to accommodate dimensional changes of the cladding without fracture. In hydrothermal corrosion testing, it was found that addition of hydrogen to the coolant reduced the rate of corrosion reactions are produced a corrosion product richer in Cr-oxide rather than Cr-hydroxide. All adherent Cr coatings successfully prevented corrosion of the underlying SiC. A 20 nm-thick, Cr-rich amorphous layer formed at the interface after irradiation with 80 MeV Xe26+ ions. Through a combination of modeling approaches, it was shown that the synergistic effects of intrinsic radiation damage in Cr and ballistic mixing of Si and C across the interface eventually lead to the destabilization of the crystalline Cr-Si-C mixture.

Download or read book In Pile Testing of CrN TiAlN and AlCrN Coatings on Zircaloy Cladding in the Halden Reactor written by Rudi Van Nieuwenhove and published by . This book was released on 2018 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is growing interest among nuclear power utilities to increase power output and to maximize electricity production. In order to deal with these more challenging conditions, new alloys have been developed. Another approach is to apply protective coatings on existing cladding zirconium alloys. Although the coatings described herein were developed in order to improve the corrosion behavior under normal conditions, it is clear that these coatings can also be applied to other materials (iron-chromium-aluminum, molybdenum, silicon carbide) presently being studied for accident-tolerant fuel. In 2011, several commercially available coatings applied by physical vapor deposition were proposed to improve the performance of existing cladding materials. Since then, these coatings have been investigated in out-pile and in-pile experiments at the Halden Reactor Project from 2011 to 2014. Boiling and pressurized water reactor (PWR) in-pile experiments were performed on small cylindrical Inconel 600 and Zircaloy-4 samples with CrN, TiAlN, and ZrO2 coatings. In all cases examined, the CrN coating came out as superior and remained completely intact after the irradiation, as evidenced by SEM analysis. Based on these promising results, an in-pile experiment with coated Zircaloy claddings (containing fuel) was performed in the Halden reactor in PWR conditions in 2014. The experimental rig contained four Zircaloy-4-clad fuel rods--three coated (CrN, TiAlN, and AlCrN) and one uncoated. Due to a mechanical deformation of tubes for cooling water within the rig, the fuel rods were insufficiently cooled, resulting in a higher-than-normal cladding temperature. Nevertheless, an SEM examination showed that the CrN coating largely remained intact apart from several local spots where the coating had cracked or disappeared. Underneath the cracked coating, oxide formation was observed in the Zircaloy-4 cladding. The TiAlN and AlCrN coatings both disappeared after the irradiation.

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 1146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Accident Tolerant Materials for Light Water Reactor Fuels written by Raul B. Rebak and published by Elsevier. This book was released on 2020-01-10 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accident Tolerant Materials for Light Water Reactor Fuels provides a description of what an accident tolerant fuel is and the benefits and detriments of each concept. The book begins with an introduction to nuclear power as a renewable energy source and the current materials being utilized in light water reactors. It then moves on to discuss the recent advancements being made in accident tolerant fuels, reviewing the specific materials, their fabrication and implementation, environmental resistance, irradiation behavior, and licensing requirements. The book concludes with a look to the future of new power generation technologies. It is written for scientists and engineers working in the nuclear power industry and is the first comprehensive work on this topic. - Introduces the fundamental description of accident tolerant fuel, including fabrication and implementation - Describes both the benefits and detriments of the various Accident Tolerant Fuel concepts - Includes information on the process of materials selection with a discussion of how and why specific materials were chosen, as well as why others failed

Download or read book CERAMIC COATINGS FOR NUCLEAR FUEL CLADDING TO ENHANCE ACCIDENT TOLERANCE written by Ece Alat and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This research is focused on developing nuclear fuel claddings with ceramic coatings that can perform well during normal operation and can withstand transient conditions such as loss of coolant accident for longer durations than current cladding material and then provide longer coping times. This was done by creating TiAlN coatings using physical vapor deposition and optimizing the deposition parameters and multilayer architecture to achieve the best performance.Zirconium-based alloys are currently widely used as cladding materials due to their low neutron absorption cross-section, good mechanical properties and high melting point. However, waterside corrosion of these alloys cause zirconium oxide formation and hydrogen generation which leads to hydrogen pick up and hydride embrittlement. Moreover, hydrogen generation in case of accelerated corrosion at higher temperatures due to loss of active cooling can lead to hydrogen explosions such as observed in the Fukushima-Daiichi accident when hydrogen explosions in the reactor building worsened the accident conditions. This accident motivated research into Accident Tolerant Fuels (ATF), which are fuels that are more forgiving in case of a loss-of-coolant-accident (LOCA). This research is an innovative approach since it considers application of TiN and TiAlN ceramic coatings on ZIRLO substrate by cathodic arc physical vapor deposition (CA-PVD), which improve corrosion resistance without a major change in core design and contribute to the design safety.Cathodic arc physical vapor deposition was used since it provides flexibility in coating properties by adjustment of deposition parameters. A systematic study was performed to identify the optimum deposition parameters to achieve enhanced adhesion of nitride-based coatings on ZIRLO substrates and best corrosion performance. The developed coatings are subjected to scratch tests and long-term corrosion tests. First, the single-layer TiAlN and single-layer TiN coating deposition on ZIRLO sheets were characterized in detail with regards to their as-deposited coating properties (topography, uniformity, crystal structure, residual stresses), failure modes during scratch testing and oxide formation after corrosion testing. Second, a multilayer coating design architecture is investigated to achieve enhanced corrosion resistance. Then the 8-layer TiN/TiAlN coatings deposited on ZIRLO tubes were exposed to long-term corrosion testing. Throughout the study, the following parameters were optimized to provide best corrosion resistance: (i) substrate surface roughness, (ii) substrate surface preparation method, (iii) titanium bond coating layer thickness, (iv) total coating thickness, (v) cathode composition, (vi) substrate bias, (vii) nitrogen partial pressure and (viii) multilayer design architecture.Mechanical performance evaluation involved scratch testing and post-scratched sample failure mode characterization. The corrosion tests were performed at Westinghouse in autoclave in static pure water at 360C and 18.7 MPa up to 128 days in order to evaluate the normal operating condition performance of the coatings. Furthermore, supercritical water testing was performed in University of Michigan autoclave at in deaerated water at 542C and 24.5 MPa for 48 hours. Additionally, differential scanning calorimetry and thermogravimetric analysis were performed to test oxidation onset point in air atmosphere. Furthermore, high temperature air oxidation testing was performed in furnace in air atmosphere up to 800C. Weight gain analysis and characterizations (optical microscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy, Raman spectroscopy) were performed to examine as-deposited coating properties and to evaluate coating performance after corrosion and mechanical testing.The results determined that 8-layer TiN/TiAlN coatings deposited with optimized parameters achieved good adhesion and substantially enhanced corrosion performance, which makes this approach promising for development of accident tolerant nuclear fuel cladding.

Download or read book Coatings for High Temperature Environments written by Amirhossein Pakseresht and published by Springer Nature. This book was released on 2023-12-05 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the recent trends in high-temperature coatings that are used to provide oxidation and wear resistance to metallic/ceramic components in extreme environments. Ceramics, intermetallics, organosilicon polymers, cermets, and other materials with great thermal stability have long been recognized for these applications. This book introduces the state of the art in coating materials and processes for high-temperature environments and identifies areas for improvement in materials selection, performance upgrades, design considerations, and manufacturing methods. The book covers a variety of high-temperature coatings prepared through various synthesis processes such as thermal spraying, physical vapor deposition, electrodeposition, and sol–gel methods. It covers corrosion/oxidation, phase stability, and thermal and mechanical behavior of high-temperature coating materials having greater thermal stability. With contributions from international researchers active in the field, this edited book features the most recent and up-to-date literature references for a broad readership consisting of academic and industrial professionals. It is suitable for graduate students as well as scientists and engineers working in the area of anti-corrosion and anti-wear resistant high-temperature coatings for industrial applications.

Download or read book Chemical Vapor Deposition of Silicon Carbide from Methylsilane and Coating of Nuclear Waste Ceramics written by and published by . This book was released on 1987 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reactor Fuels Materials and Systems under Extreme Environments written by Wenzhong Zhou and published by Frontiers Media SA. This book was released on 2022-03-25 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Vapor Deposition of Ta2O5 Corrosion Resistant Coatings written by and published by . This book was released on 1992 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon carbide and silicon nitride heat engine components are susceptible to hot corrosion by molten Na2SO4 which forms from impurities present in fuel and the environment. Chemically vapor deposited Ta2O5 coatings are being developed as a means to protect components from reaction with these salts and preserve their structural properties. Investigations to optimize the structure of the coating have revealed that the deposition conditions dramatically affect the coating morphology. Coatings deposited at high temperatures are typically columnar in structure; high concentrations of the reactant gases produce oxide powders on the substrate surface. Ta2O5 deposited at low temperatures consists of grains that are finer and have significantly less porosity than that formed at high temperatures. Samples of coatings which have been produced by CVD have successfully completed preliminary testing for resistance to corrosion by Na2SO4.

Download or read book Deposition and Study of Silicon Carbide Coatings on Silica Substrates Using Laser induced Chemical Vapor Deposition written by Christopher J. Jensen and published by . This book was released on 2005 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Silicon Carbide Coatings by Plasma enhanced Chemical Vapor Deposition on Silicon and Polyimide Substrates written by Pramod Chakravarthy and published by . This book was released on 1995 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1986 with total page 1162 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reactor Core Materials written by and published by . This book was released on 1964 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reactor Materials written by and published by . This book was released on 1966 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Magnetron Sputtering and Corrosion of Ti Al C and Cr Al C Coatings for Zr alloy Nuclear Fuel Cladding written by Devin Alan Roberts and published by . This book was released on 2016 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: The disaster at the Fukushima Daiichi Nuclear Power Plant in March 2011 bought renewed focus to the issue of corrosion in nuclear fuel cladding applications. This thesis reports on the background behind these issues, the investigation strategy, and the analysis of experiments focused on mitigating oxidation of Zr-alloy fuel cladding. This thesis seeks to develop magnetron sputtered Ti-Al-C and Cr-Al-C coatings for Zr-alloy substrates and characterize the as-deposited and corroded samples. Ti-Al-C and Cr-Al-C coatings were deposited onto ZIRLO, Si, and Al2O3 [Aluminum Oxide] substrates under various sputtering conditions. A combinatorial sputtering method was employed to refine the sputtering parameters. Following each deposition, the coatings were characterized using grazing incidence x-ray diffraction. The crystal structures of the as deposited Ti-Al-C coatings are consistent with TiC [Titanium Carbide] with aluminum substituting onto carbon sites and TiAl3 [Titanium Aluminide]. The as deposited Cr-Al-C coatings were determined to be Cr2AlC [Chromium Aluminum Carbide] MAX phase. After characterization of the as-deposited coatings, corrosion tests in water were performed on ZIRLO coupons, in a 360 degrees Celsius autoclave. In this thesis, each of the coatings exhibited significant weight gain compared to conventional Zr-alloy claddings. Following corrosion, the samples were analyzed using grazing incidence x-ray diffraction. Results of corrosion testing show the Ti-Al-C coatings of this study are not fit for the application coatings for nuclear cladding, as multiple oxide and hydroxide phases were produced. Much of the Cr-Al-C the coating spalled off the substrate during corrosion testing. Cr-Al-C coatings that survived the corrosion testing produced phases consistent with Cr2AlC MAX phase, Al2O3, and Cr2O3 [Chromium Oxide]. In addition to the corrosion study, an in-situ high temperature grazing incidence x-ray diffraction study was performed on the Cr-Al-C on Al2O3 sample. Analysis of the high temperature data suggest the Cr2AlC MAX undergoes a disordered to ordered transformation of the phases Cr and Al sites at increasing temperatures.

Download or read book Quantification of Crack Morphology in Chemically Vapor Deposited Silicon Carbide Coatings on Carbon carbon Substrates written by Brian E. Mast and published by . This book was released on 1993 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book INIS Atomindex written by and published by . This book was released on 1988 with total page 902 pages. Available in PDF, EPUB and Kindle. Book excerpt: