Positron annihilation studies of Eurofer97/ODS steels after helium ion implantation

The paper briefly reviews our positron annihilation studies performed on Eurofer97 steel and its ODS variant, performed in the last about 20 years. Various aspects of radiation environments foreseen for these materials were experimentally simulated via ion implantation and studied by a combination of non-destructive characterization techniques. The primary characterization tools in these studies were two techniques based on positron annihilation, namely positron annihilation lifetime spectroscopy (PALS) and Coincidence Doppler Broadening (CDB) technique. In addition to bulk studies utilizing conventional radioisotope positron sources, ion-implanted specimens were analysed using slow positron beams. This review summarizes the key findings of these techniques concerning the nature of the radiation resistance of EUROFER/ODS steels.