Comparison on Determination of Oxygen Content of Zirconium Oxide in Zircaloy by EDS and EELS

X-ray energy dispersive spectrometer (EDS) and electron energy loss spectrometer (EELS) were used to determine the content (atomic fraction) and distribution of oxygen in the zirconium oxide formed in zircaloy respectively, and the measurement results were compared. The results show that the oxygen content of zirconium oxide was determined to be 67.1% by EELS, which was close to the oxygen content of ZrO₂ (66.7%). But the oxygen content in the zirconium oxide was determined to be 30.1% by EDS, which was far below the oxygen content of ZrO₂. The selected area electron diffraction further confirmed that the zirconium oxide was ZrO₂ phase, and this was consistent with the results of EELS analysis. Thus it can be concluded that the oxygen content determined by EELS has higher accuracy than that determined by EDS, and EELS can be used for direct calibration of oxides. Moreover, the aggregation condition of oxygen element can be clearly displayed by EELS imaging, but in EDS imaging, no aggregation condition of oxygen element can be observed.