Zirconium and its alloys are used as nuclear fuel cladding materials due to their excellent mechanical properties, corrosion resistance, and small thermal neutron absorption cross-sections. When exposed to radiation, a large number of irradiation-induced defects emerge in the zirconium alloy, seriously diminishing its mechanical properties and service life. This study employs molecular dynamics simulations to investigate the interaction between the stacking fault pyramid and point defects (i.e., interstitial atoms and vacancies) in zirconium. It is found that, at 0 K and 300 K, the stacking fault pyramid exclusively absorbs interstitial atoms; while at 600 K, it absorbs both interstitial atoms and vacancies. To explain this phenomenon, the binding energy of interstitial atoms/vacancies and the stacking fault pyramid is calculated. The results indicate that the binding energy is related to the type/position of point defects: the binding energy of interstitial atoms is much greater than that of vacancies, making interstitial atoms more likely to be absorbed. At the same time, the proximity to the stacking fault pyramid amplifies the binding energy, rendering both point defects more susceptible to absorption. These simulation results provide a new insight into understanding the growth mechanism of irradiation-induced defects in zirconium.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |