A replica technique for extracting precipitates from zirconium alloys for transmission electron microscopy analysis

A reliable two-stage carbon replica technique has been developed to extract precipitates from zirconium alloys. Using this technique, all precipitating phases can be extracted from Zircaloy-2, Zr-Cr-Fe, and Zr-Nb-Fe alloys. Precipitate identification using EDS X-ray analysis and convergent beam electron diffraction was greatly facilitated in comparison to thin foils. In addition, the sensitivity for the detection of trace elements in particles was increased using extraction replicas. The chemical compositions of the precipitates as determined from both replica and thin foils were in excellent agreement.