Brower, Jeffrey Owen, Glazoff, Michael Vasily, Eiden, Thomas John, and Rezvoi, Aleksey Victor. Evaluation of Corrosion of the Dummy “EE” Plate 19 in YA Type ATR Fuel Element During Reactor PALM Cycles. United States: N. p., 2016.
Web. doi:10.2172/1364230.
Brower, Jeffrey Owen, Glazoff, Michael Vasily, Eiden, Thomas John, & Rezvoi, Aleksey Victor. Evaluation of Corrosion of the Dummy “EE” Plate 19 in YA Type ATR Fuel Element During Reactor PALM Cycles. United States. doi:10.2172/1364230.
Brower, Jeffrey Owen, Glazoff, Michael Vasily, Eiden, Thomas John, and Rezvoi, Aleksey Victor. Mon .
"Evaluation of Corrosion of the Dummy “EE” Plate 19 in YA Type ATR Fuel Element During Reactor PALM Cycles". United States.
doi:10.2172/1364230. https://www.osti.gov/servlets/purl/1364230.
@article{osti_1364230,
title = {Evaluation of Corrosion of the Dummy “EE” Plate 19 in YA Type ATR Fuel Element During Reactor PALM Cycles},
author = {Brower, Jeffrey Owen and Glazoff, Michael Vasily and Eiden, Thomas John and Rezvoi, Aleksey Victor},
abstractNote = {Advanced Test Reactor (ATR) Cycle 153B-1 was a 14-day, high-power, powered axial locator mechanism (PALM) operating cycle that completed on April 12, 2013. Cycle 153B-1 was a typical operating cycle for the ATR and did not result in any unusual plant transients. ATR was started up and shut down as scheduled. The PALM drive physically moves the selected experiments into and out of the core to simulate reactor startup and heat up, and shutdown and cooldown transients, while the reactor remains in steady state conditions. However, after the cycle was over, several thousand of the flow-assisted corrosion pits and “horseshoeing” defects were readily observable on the surface of the several YA-type fuel elements (these are “dummy” plates that contain no fuel). In order understand these corrosion phenomena a thermal-hydraulic model of coolant channel 20 on a YA-M fuel element was generated. The boundaries of the model were the aluminum EE plate of a YA-M fuel element and a beryllium reflector block with 13 horizontal saw cuts which represented regions of zero flow. The heat generated in fuel plates 1 through 18 was modeled to be passing through the aluminum EE plate. The coolant channel 20 width was set at 0.058 in. (58 mils). It was established that the horizontal saw cuts had a significant effect on the temperature of the coolant. The flow, which was expected to vary linearly with gradual heating of the coolant as it passed through the channel, was extremely turbulent. The temperature rise, which was expected to be a smooth “S” curve, was represented by a series temperature rise “humps,” which occurred at each horizontal saw cut in the beryllium reflector block. Each of the 13 saw cuts had a chamfered edge which resulted in the coolant flow being re-directed as a jet across the coolant channel into the surface of the EE plate, which explained the temperature rise and the observed sscalloping and possibly pitting degradation on the YA-M fuel elements. In the case of scalloping (horseshoeing) a surprising similarity of that defect to those appearing on aluminum plate rolled in over-lubrication conditions, were established. In turn, this made us think that the principal feature responsible for the appearance of these defects, was horizontal cuts in the Be neutron reflector created to arrest the propagation of large vertical crack(s) in Be in PALM cycles with higher overall fluence. This assumption was confirmed by the results of thermo-hydraulic simulations. The neutronics data for these modeling experiments were provided using rradiation simulations (MCNP, HELIOS). In the case of FAC and pitting corrosion the following corrective measures were proposed based upon the results of JMatPro modeling (TTT- and CCT-diagrams): change the practice of thermo-mechanical treatment of dummy plates in the future by adding blister anneal before program anneal, immediately after cold rolling of AA6061 ingot. This step will allow achieving complete recrystallization, eliminating of strengthening due to metastable precipitates, and reduce the possibility of forming sharp microstructural features upon the surface. Additionally it may prevent the formation of Fe-Al galvanic couples localized around such sharp particles. These recommendations were discussed with BWXT representatives and agreed upon by all parties. The new batch of plate manufactured using thus modified thermo-mechanical treatment is expected to be loaded into the ATR soon.},
doi = {10.2172/1364230},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Aug 01 00:00:00 EDT 2016},
month = {Mon Aug 01 00:00:00 EDT 2016}
}
