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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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
Germany’s Unterweser completes removal of steam generators
All four steam generators at Germany’s Unterweser nuclear power plant have been removed from the reactor building, plant owner PreussenElektra has announced. The single-unit pressurized water reactor was shut down in 2011 as part of Germany’s decision to phase out nuclear energy. Decommissioning and dismantlement of the reactor began soon after PreussenElektra was granted a permit for the work in February 2018.
J. T. A. Roberts, E. Smith, N. Fuhrman, D. Cubicciotti
Nuclear Technology | Volume 35 | Number 1 | August 1977 | Pages 131-144
Technical Paper | Fuel | doi.org/10.13182/NT77-A31856
Articles are hosted by Taylor and Francis Online.
Results of three related projects undertaken to elucidate the mechanism of Zircaloy cladding fracture caused by pellet-cladding interaction (PCI) in water reactor fuel rods are described. A detailed microscopic examination of incipient i.d. cladding defects in some Maine Yankee Core I fuel rods determined that these defects and clad penetrations in related rods were caused by a PCI mechanism that was promoted by chemical species, i.e., stress corrosion cracking (SCC). A consideration of the internal fuel rod chemistry and fission product distribution indicates that one potential agent for SCC of Zircaloy cladding is iodine released from Csl deposited on the i.d. surface and another is cadmium metal. A simple analytical model of crack propagation in Zircaloy cladding based on linear elastic fracture mechanics indicates two possible rate-controlling events, depending on the value of the stress intensification KISCC. If KISCC for irradiated Zircaloy is very low, i.e., on the order of 2.2 to 3.3 MN/m3/2 (2 to 3 ksi ), crack growth is relatively easy, and hence the rate-limiting step must be the nucleation of sharp cracks in the cladding i.d. surface. However, if KISCC for irradiated Zircaloy is relatively large, i.e., ≥11 MN/m3/2 (10 ksi ), a high interfacial friction coefficient, for example, caused by fuel-clad bonding, would be required to propagate the i.d. defect.
