Characterization of M2X formed during 5 MeV Fe2+ irradiation.

The growth of M 2 X phase in HT9 irradiated to high dpa was explored using self-ion irradiation. HT9 was pre-implanted with 10 appm He and irradiated with a raster-scanned Fe 2+ beam with a damage rate of ∼1 × 10 −3 dpa/s at 460 °C. The precipitation of M 2 X was observed and a combination of high resolution transmission electron microscopy (HRTEM), energy filtered transmission electron microscopy (EFTEM) and diffraction analysis was used to characterize the Cr-rich carbide observed at 250 dpa and above. Cr 2 C was determined to be semi-coherent with the matrix such that [ 100 ] C r 2 C / / [ 100 ] α and [ 001 ] C r 2 C / / [ 10 1 ¯ ] α .with a = 2.71 Å and c = 2.82 Å. [ABSTRACT FROM AUTHOR]