Basic evaluation on material attractiveness of isotopic plutonium barrier

Abstract

Material attractiveness evaluations based on isotopic Plutonium barrier compositions have been investigated for evaluating intrinsic features of proliferation resistance such as decay heat (DH), spontaneous fission neutron (SFN), as well as attractiveness concepts of figure of merit (FOM) and “attractiveness” (ATTR) as a function of diluted fraction of even mass Plutonium to Pu-239 composition. The DH and SFN compositions increase significantly with increasing diluted fraction of even mass Plutonium, except for DH of Pu-242. It shows that diluted fraction of Pu-238 contributes most significantly to the DH ad SFN compositions at certain diluted fractions. Only diluted fraction of Pu-238 can reach a DH composition level of MOX fuel for small diluted fraction and an SFN level of MOX fuel can be reached by all diluted fractions of even mass Plutonium. It requires more than 80% of diluted Pu-238 fraction to achieve a low material attractiveness based on FOM1 formula and there is no available diluted fraction for Pu-240 and Pu-242 for reaching it. It is easier to reach a low material attractiveness by using FOM2 than that of FOM1 caused by additional contribution of the SFN component, as well as ATTR, which also considers both DH and SFN components. The material attractiveness of FOM2 and ATTR as a function of diluted even mass Plutonium fractions are shown in similar trend, which requires some diluted fraction depending on even mass Plutonium for achieving low material attractiveness of FOM 2 and practically unusable level of ATTR.