SIMS image analysis of D2O migration in ZrO2 thin films

Abstract

The diffusion of D2O into and through oxide films on Zr-Nb alloys was investigated using secondary ion mass spectrometry (SIMS) image analysis. In preparation for this, the microscopic structures of the oxide were studied in relation to the grain structures in the underlying alloy. On alloys containing low concentrations of niobium (1-2.5 wt.%), the oxide was found to exhibit more localized growth, particularly above grain boundaries in the alloy. Such oxide regions appeared to be considerably more porous to D2O ingress. By contrast, the oxide film on the Zr 20 wt.% Nb alloy was found to be the most resistant to D2O ingress; no local regions of higher porosity could be found. © 1997 John Wiley & Sons, Ltd.