Work

Optimally incorporating intra-cascade spatial correlations into mean-field cluster dynamics for radiation damage modeling

Year: 2025

Type: article

Abstract: The mean-field cluster dynamics (CD) model predicts microstructure evolution over longer spatio-temporal scales and damage accumulation up to high doses, which is typically used to relate damage production to material properties. However, the inability of CD to treat intra-cascade spatial correlations is one of the key issues for the accuracy of radiation damage modeling. Beyond the current solutions of using the ambiguous annealing time for cascade homogenization, we develop a characteristic-time annealing methodology that optimally embeds intra-cascade spatial correlations into the source term, establishing the CD-SC model in the continuum framework. This approach enables unified modeling of defect evolution under both monoenergetic ion bombardment and continuous neutron spectrum irradiation. Defect size distributions predicted by CD-SC are consistent with simulation results of monoenergetic recoils and self-ion irradiated experimental observations. The characteristic times for iron and tungsten are in the orders of us and ps, respectively, breaking the traditionally accepted values (~ns) under the room-temperature condition. We further reveal that the characteristic time is proportional to the relative positions of primary defects and inversely proportional to the competition of defect reaction and sink absorption that are related to damage energy as well as temperature and material properties (sink character and migration energy), respectively. Finally, CD-SC is applied to quantitative simulations of neutron radiation damage under fission and fusion conditions. The present approach builds an accurate defect production term and thus can provide reliable predictions of the lifetime service performance of nuclear materials.

Source: Nuclear Materials and Energy

DOI: 10.1016/j.nme.2025.102001

Authors: Qirong Zheng, Panfei Tang, Jun Liu, Chuanguo Zhang, Yonggang Li, Zhi Zeng

Institutions: University of Science and Technology of China, Chinese Academy of Sciences, Institute of Solid State Physics

Language: English

Topic: Fusion materials and technologies

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,190

Funders: National Natural Science Foundation of China, Chinese Academy of Sciences, Natural Science Foundation of Anhui Province