Effects of Spallation neutron irradiation on single crystals of Iron, Nickel, Niobium and Stainless Steel

Abstract

Abstract Single crystals of Iron, Nickel, Niobium and Stainless Steel (SS316) subjected to prolonged neutron irradiation in the Los Alamos Spallation Source for a period of one year have been studied using both small angle, and single crystal neutron diffraction. Small Angle Scattering show no evidence of any large radiation induced inhomogeneities in the pure metals, while regions of ∼ 65 A diameter are found in the irradiated SS316. Combining the s.a.s. measurements with the single crystal diffraction data these regions are attributed to the formation of coherent precipitates of Ni-Cr. However, a low concentration of point defects (<2.5 at %) is introduced in all the materials by the irradiation process. No significant radiation induced dilatation of the lattice is found in any of the materials.