Materials in Nuclear Energy Systems (MiNES) 2021: Integrated Phenomena- Session II
Program Organizers: Todd Allen, University of Michigan; Clarissa Yablinsky, Los Alamos National Laboratory; Anne Campbell, Oak Ridge National Laboratory
Wednesday 10:30 AM
November 10, 2021
Room: Allegheny
Location: Omni William Penn Hotel
Session Chair: Gabriel Meric, Kairos Power LLC
10:30 AM Invited
Kinetics of SiC Reaction with Water and Oxygen Under Light Water Reaction Conditions: Peter Doyle1; Steven Zinkle2; Stephen Raiman3; 1Oak Ridge National Laboratory; 2University of Tennessee, Knoxville; 3Texas A&M University
SiCf/SiC composites have been identified as a potential accident tolerant fuel cladding. Among the R&D topics requiring investigation, aqueous corrosion behavior under normal operating conditions requires improved understanding. In the present work, SiC was exposed to high purity pressurized water in a constantly recirculating autoclave environment. Exposures ranged between 288°C and 350°C for times up to 2000 h, with either 1-4ppm O2 or 0.15-3ppm H2 dissolved in the water. Oxygen reacted with SiC with a reaction order of 1 and was initially linear with time until grain fallout became prevalent. No localized attack was observed in the absence of oxygen and uniform dissolution is predicted to be below 4μm/5 years, an acceptable rate. A predictive equation is given and compared to other published data. Recommendations are made for future testing parameters, include sample preparation. Funding was provided by the U.S. Department of Energy Office of Nuclear Energy, Advanced Fuel Campaign.
11:10 AM
Structural Materials Testing for the Westinghouse Lead Fast Reactor: Mike Ickes1; Paolo Ferroni1; 1Westinghouse Electric Company
Westinghouse continues to develop the Lead Fast Reactor (LFR) as its Generation IV reactor concept, with the mission to provide safe, sustainable, and especially economical carbon-free electricity generation to global market. The Westinghouse LFR is a 950 MWt (~460 MWe) pool-type reactor with compact in-vessel heat exchangers and no intermediate heat transport system. The operation of an LFR at temperatures greater than approximately 500°C is challenged by liquid lead corrosion of structural materials. Recognizing that some key components such as the reactor vessel and the primary pumps will operate at cold leg temperature (~400°C), some others will operate at higher temperatures. Investigations into materials integrity under reactor operating conditions to allow operation at higher temperature are therefore an important aspect of LFR development to maximize the economic performance of the LFR. Some key aspects and select results from the R&D campaign supporting the Westinghouse LFR will be presented and discussed.
11:30 AM
3D Reconstruction and Quantification of Oxide Nano-porosity in Zirconium Alloys: Hongliang Zhang1; Adrien Couet1; Taeho Kim1; William Howland2; 1University of Wisconsin-Madison; 2Uw-Madison
In the corrosion of Zirconium alloy, the oxide grows at a decreasing rate until reaching critical thickness, followed by the sudden loss of the protective property in the oxide and growth of a new cycle of oxide. The oxidizing-induced pores are pathways to oxidizing species in the oxide. TEM is usually used to determine pore density and size. However, due to the size of the pores and the thickness of the TEM samples, some of the pores are invisible in TEM at only one angle. Manually counting pores will also bring some artifacts. We precisely quantify oxide porosity in corroded Zircaloy-4 as function of exposure time and temperatures using manual and machine-learning-based counting. The structure and distribution of pore in different depths are analyzed to study porosity interconnection using 3D pore reconstruction. Then discussed as function of substrate texture to study lattice mismatch vs stress-driven oxide growth.