Analysis on the open-volume defect of structural material in fusion reactor using the positron annihilation spectroscopy

Since 2011, Advanced Reduced-Activation Alloy (ARAA) as a Reduced Activation Ferritic-Martensitic (RAFM) steel for International Thermonuclear Experimental Reactor (ITER) was developed by Korea Atomic Energy Research Institute (KAERI). ARAA was created by adding 0.01 wt% Zr to 9Cr-1.2W based ferritic-martensitic steels. The structural material of the fusion reactor must be able to withstand high temperature and energetic neutron irradiation. The open-volume defect, dislocation is mainly generated due to heat treatment temperature and rolling method. It is important to know the defect information under these conditions. In this study, the Positron Annihilation Spectroscopy (PAS) was used for defect analysis of ARAA