Evaluation of neutron radiation damage on gold microstructure using MCNP

The effects of radiation interaction with materials have been studied over the years on metals, semiconductors, and other alloys. The result of these interactions constitutes microstructural effects, like point defects, dislocation loops, and void swellings. The accumulation of these defects results to damage on the macroscopic scale. This study is aimed to predict the magnitude of radiation damage in gold sample due to neutron irradiation. Neutron flux, displacement-per-atom rate, as well as heat deposition, were calculated in MCNP6.2, using the SAFARI-1 reactor model. The total neutron flux and dpa rate in the gold sample were determined to be 2.262 × 10¹¹ n.cm⁻².s⁻¹ and 5.209 × 10⁻⁷ s⁻¹ respectively. Also, the total heat deposition due to neutrons and photons was 2.515 ×10⁻⁶ W.g⁻¹ and 0.513 W.g⁻¹, respectively. Hence, the predicted neutron dpa and flux for the gold sample in this study suggest a heavy damage regime.