Influence of annealing in air on transport properties of long-time oxidized layers of zirconium alloys

The change of resistivity and permittivity of oxide films grown 1554 days in water at 360 °C on tubes of Zr1Nb, ZrSnNb(Fe) and IMP Zry-4 was investigated by I-V measurements after long-time annealing in air at 123 °C. Thereby the room temperature resistivity, highest in Zry-4W and lowest in Zr1Nb, increased by more than two orders of magnitude due to a strong decrease of mobility, with nearly constant carrier concentration. The polarity of the zero current changed from negative to positive values in the pA range. The changes are thought to be due to continued oxidation.