Oxide layers of Zr-1% Nb under PWR primary circuit conditions

Oxide layers were grown on Zr-1% Nb under conditions simulating those in VV ER-type pressurised water reactors (PWRs), viz. in berate solutions in an a utoclave at 290 degreesC. The layers were characterised by various methods: their respective thickness values were determined by weight gain measureme nts, Rutherford backscattering (RBS), nuclear reaction analysis (NRA) and s canning electron microscopy (SEM); the electrical properties were tested by electrochemical impedance spectroscopy. The results show that the oxide la yer on Zr-1% Nb is homogeneous and somewhat thicker than that on Zircaloy-4 . (C) 2001 Elsevier Science B.V. All rights reserved.