Refine your search:     
Report No.

Fundamental study on segregation behavior in U-Zr-Fe-O system during solidification process

Sudo, Ayako; Mizusako, Fumiki*; Hoshino, Kuniyoshi*; Sato, Takumi; Nagae, Yuji; Kurata, Masaki

Cooling rate of molten core materials during solidification significantly affects the segregation of major constituents of fuel debris. To understand general tendency of the segregation, liquefaction/solidification tests of simulated corium (UO$$_{2}$$, ZrO$$_{2}$$, FeO, B$$_{4}$$C and sim-FP oxides) were performed. Simulated corium was heated up to 2600$$^{circ}$$C under Ar atmosphere and then cooled down with two different cooling processes; furnace cooling (average cooling rate is approximately 744$$^{circ}$$C/min) and slow cooling (cooling rate in 2600$$^{circ}$$C$$sim$$2300$$^{circ}$$C is 5$$^{circ}$$C/min and in 2300$$^{circ}$$C$$sim$$1120$$^{circ}$$C is approximately 788$$^{circ}$$C/min). Element analysis detected three oxide phases with different composition and one metal phase in both solidified samples. Solubility of FeO in these oxide phases was mostly fixed to be 12$$pm$$5at% in both samples, which is in reasonable accordance with the value estimated from UO$$_{2}$$-ZrO$$_{2}$$-FeO phase diagrams. However, a significant grain-growth of one oxide phase, rich in Zr-oxide, was detected only in the slowly cooled sample. The composition of this particular oxide phase is comparable to the initial average composition. The condensation is considered to be caused by the connection of remaining liquid agglomerates during slow solidification.



- Accesses





[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.