Accommodation of tin in tetragonal ZrO2

作者：Bell B D C; Murphy S T; Burr P A; Grimes R W; Wenman M R^*

来源：Journal of Applied Physics, 2015, 117(8): 084901.

DOI：10.1063/1.4909505

Atomic scale computer simulations using density functional theory were used to investigate the behaviour of tin in the tetragonal phase oxide layer on Zr-based alloys. The Sn-Zr(x) defect was shown to be dominant across most oxygen partial pressures, with Sn-Zr '' charge compensated by V-O(center dot center dot) occurring at partial pressures below 10(-31) atm. Insertion of additional positive charge into the system was shown to significantly increase the critical partial pressure at which Sn-Zr '' is stable. Recently developed low-Sn nuclear fuel cladding alloys have demonstrated an improved corrosion resistance and a delayed transition compared to Sn-containing alloys, such as Zircaloy-4. The interaction between the positive charge and the tin defect is discussed in the context of alloying additions, such as niobium and their influence on corrosion of cladding alloys.

• 出版日期2015-2-28