Study of Doppler broadening in neutron irradiated ADS related materials using positron annihilation spectroscopy

Doppler broadening measurements for radiation damages by neutrons up to 10 MeV in elements Al, Cu and composite material Brass has been carried out using Positron Annihilation Spectroscopy (PAS). These samples has been irradiated by 5.0 Ci Am+Be neutron source for different time periods ranging from 24 hours to 120 hours in order to obtain different neutron fluency. The available neutron flux at irradiated position was 3.3×105 n/cm2 s. A positron source 22Na of strength 35mCi was used and subsequently S and W parameters has been calculated for Doppler Broadening using PAS. SEM measurements have also taken for the surface study of these materials. SEM measurement shows substantial changes in the surface of the materials after the irradiation.