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The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Vincent Bouineau, Gilles Bénier, Dominique Pêcheur, Joël Thomazet, Antoine Ambard, Martine Blat
Nuclear Technology | Volume 170 | Number 3 | June 2010 | Pages 444-459
Technical Paper | Materials for Nuclear Systems | doi.org/10.13182/NT10-A10330
Articles are hosted by Taylor and Francis Online.
The waterside corrosion kinetics of Zircaloy-4 are accelerated in pressurized water reactors (PWRs) in comparison with autoclaves. Beyond this comparison, an enhancement of oxidation rate - called phase III - can be observed from the third reactor cycle. This results in significant oxide thicknesses at high burnups. Several hypotheses have been devised to explain this phase III of Zircaloy-4 in PWRs, but none have been fully validated. In an attempt to better understand the oxidation acceleration phenomenon affecting Zircaloy-4 in PWRs, we decided to analyze the in-reactor corrosion of Zircaloy-4 by quantifying the acceleration factor KPWR. This was defined as the multiplication factor to be applied to the oxidation rate in an autoclave to obtain the kinetics in a PWR (with an equivalent metal-oxide interfacial temperature and taking into account both the power and thermal-hydraulic histories). This analysis was based on oxide thicknesses formed on Zircaloy-4 cladding containing UO2 or mixed-oxide fuel and having been irradiated for one to six cycles in French PWRs. This analysis enabled us to demonstrate the following:1. KPWR is always >1, which clearly shows an acceleration in the Zircaloy-4 oxidation kinetics in a reactor.2. KPWR is equivalent to [approximately]2 for rods having been subjected to one or two cycles.3. Above two reactor cycles, KPWR increases with the level of irradiation and ends up reaching values close to 6. This KPWR increase is representative of phase III.4. KPWR and its variations are not directly related to the increase in the fluence. Phase III is not associated with a burnup threshold.5. Phase III seems to be related to a threshold that is a function of the oxide layer thickness.6. The precipitation of hydrides could be used to define a threshold that is a function of the oxide layer thickness above which phase III occurs. This hypothesis is consistent with the thickness at which KPWR increases. Furthermore, phase III observed is consistent with the known increase in the oxidation kinetics of samples with hydride rims in an autoclave.Therefore, acceleration of the oxidation kinetics in a reactor (compared with an autoclave) is not constant but does seem to be a complex function of different variables such as time, temperature, and both the thermal and neutron fluxes. Furthermore, the precipitation of hydrides seems to be a first-order factor triggering phase III of Zircaloy-4 in a reactor.