Oxide dispersion strengthened Fe–12Cr steel in three dimensions: An electron tomography study

In this work, scanning-transmission electron microscope tomography and atom-probe tomography were successfully applied to characterize the Y- and Cr-rich secondary phases present in an oxide dispersion strengthened reduced activation Fe–12Cr alloy in three dimensions. Electron energy loss spectroscopy, energy dispersive spectroscopy and energy filtered transmission electron microscopy were used to obtain analytical information about the region used for electron tomography reconstruction. The results obtained with these techniques provided accurate information regarding the Y-rich nanoparticle dispersion and chemistry and their association with the Cr-rich precipitates present in the alloy. Reconstructions show that Y-rich nanoparticles are frequently found to be embedded within the larger Cr-rich carbides and oxides, which would decrease the amount of nanoparticles capable of strengthening the matrix.