Microstructural changes in a low-activation Fe-Cr-Mn alloy irradiated with92 MeV Ar ions at 450 degrees C

In this work, a solution-annealed specimen of a low-activation Fe-Cr-Mn all oy was irradiated with 92 MeV Ar ions at 450 degreesC to a dose of 1.7 x 10 (21) m(-2) which was expected to produce a peak displacement damage of 90 d pa. After irradiation, damage microstructure was investigated from the cros s-sectional specimens using a transmission electron microscope. High number density cavities were observed in the peak dose region. Size of cavities w as the largest at the peak displacement damage. Formation of alpha -phase w as found at a grain boundary in the peak dose region. Well-dispersed carbid e particles was found in the matrix. The carbide/matrix interfaces supplied favorable site for growth of large cavities, whereas only small cavities w ere found inside the particles. (C) 2000 Elsevier Science B.V. Ail rights r eserved.