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Experts talk on developing the isotope supply chain
The American Nuclear Society recently hosted a webinar, “Securing the Isotope Supply Chain: A Growing Global Challenge,” featuring experts from a variety of private and public institutions who discussed the current state of the isotope supply chain, the necessity for strengthening that chain, and the tools available to develop a more robust system.
To watch the full webinar, click here.
Takanori Kameyama, Tetsuo Matsumura, Motoyasu Kinoshita
Nuclear Technology | Volume 106 | Number 3 | June 1994 | Pages 334-341
Technical Paper | Nuclear Fuel Cycle | doi.org/10.13182/NT94-A34963
Articles are hosted by Taylor and Francis Online.
The peripheral region of a high burnup light water reactor (LWR) fuel pellet shows a microstructure that is different from the as-fabricated microstructure. The region where the microstructure change occurs (the rim region) is highly porous, and the original grains in the rim region are divided into much smaller subgrains. The electron probe microanalysis data of high burnup fuels indicate fission gas depletion in the rim region as well as in the central region. The burnup in the rim region is enhanced by built-up plutonium derived from a 238U self-shielding effect, which is called a rim effect. The rim effect accelerates microstructure change in the peripheral region. We developed a detailed burnup analysis code ANRB computing the rim effect in LWR fuels. We have verified the ANRB code performance with the data of the High Burnup Effects Program. The analysis shows that the microstructure change occurs where local burnup gets to the threshold burnup of 70 to 80 MWd/kg U in both pressurized water reactor and boiling water reactor types of fuels. The threshold burnup never changes with the plutonium/uranium burnup ratio or fission rate during the irradiation. The storage of radiation damage is expected to cause the microstructure change.
