Lithium doping of candidate fusion reactor alloys to simulate simultaneous helium and damage production

Abstract

Lithium and boron doping techniques are possibilities for simulating simultaneous helium production and displacement damage in bulk specimens of non-nickel bearing materials in fast fission reactors. Rapid solidification processing and powder metallurgy salt decomposition were investigated for the preparation of lithium doped alloys. For convenience, austenitic stainless steel was doped rather than non-nickel bearing alloys for which this technique is ultimately designed. Neutron autoradiography verified a uniform distribution of lithium in the alloy. Although the same approach can be used to dope alloys uniformly with a stable boron compound, thus reducing the problem of grain boundary segregation and coarsening, the use of lithium doping should be an advantage because this dopant produces only helium and hydrogen when irradiated in a fast fission reactor. These elements are also produced in materials in the CTR environment.