论文标题
纳米氧化物沉淀及其相关稳定性的动力学蒙特卡洛模型在中子辐射下的Fe-Ti-Y-O系统下
Kinetic Monte Carlo Modelling of Nano-oxide Precipitation and its Associated Stability under Neutron Irradiation for the Fe-Ti-Y-O system
论文作者
论文摘要
在开发核材料的同时，在长期辐照方面预测其行为跨越了几十年，这构成了重大挑战。我们开发了一种新型的动力学蒙特卡洛（KMC）模型，以探索Y-Ti-O氧化物沿纳米结构的铁素性合金（NFA）内晶界的降水行为。该模型还评估了氧化物对中子照射的响应，即使在所需的长DPA范围内，反应器组件的模拟辐射损伤水平也提高了模拟的辐射损伤水平。我们的模拟研究了温度和晶界下沉如何影响1023 K，1123 K和1223 K的热处理过程中12YWT样合金的氧化物特性。在我们的模拟中观察到的氧化物特性与现有文献非常吻合。此外，发现晶界对降水的影响很小。随后的模拟中使用了所得的氧化物构型和位置，这些模拟将它们暴露于模拟中子辐射，以在三个温度下的总累积剂量为8 dpa：673 K，773 K和873 K，并以10^（-3），10^（-4）和10^（-5）和10^（ - 5）DPA的剂量速率为10^（-3），10^（ - 3），DPA。这证明了氧化物大小和剂量速率之间的预期逆关系。在873 K和10^（-3）的长期辐照模拟中，将DPA/S取出到66 dPa，发现晶界附近的氧化物更容易溶解。此外，我们对14YWT样合金进行了辐照模拟，以从中子辐照实验中再现发现。类似14yWT的合金中较大的氧化物没有溶解并显示出与实验结果相似的稳定性。
While developing nuclear materials, predicting their behavior under long-term irradiation regimes spanning decades poses a significant challenge. We developed a novel Kinetic Monte Carlo (KMC) model to explore the precipitation behavior of Y-Ti-O oxides along grain boundaries within nanostructured ferritic alloys (NFA). This model also assessed the response of the oxides to neutron irradiation, even up simulated radiation damage levels in the desired long dpa range for reactor components. Our simulations investigated how temperature and grain boundary sinks influenced the oxide characteristics of a 12YWT-like alloy during heat treatments at 1023 K, 1123 K, and 1223 K. The oxide characteristics observed in our simulations were in good agreement with existing literature. Furthermore, the impact of grain boundaries on precipitation was found to be minimal. The resulting oxide configurations and positions were used in subsequent simulations that exposed them to simulated neutron irradiation to a total accumulated dose of 8 dpa at three temperatures: 673 K, 773 K, and 873 K, and at dose rates of 10^(-3), 10^(-4), and 10^(-5) dpa/s. This demonstrated the expected inverse relationship between oxide size and dose rate. In a long-term irradiation simulation at 873 K and 10^(-3) dpa/s was taken out to 66 dpa and found the oxides in the vicinity of the grain boundary were more susceptible to dissolution. Additionally, we conducted irradiation simulations of a 14YWT-like alloy to reproduce findings from neutron irradiation experiments. The larger oxides in the 14YWT-like alloy did not dissolve and displayed stability similar to the experimental results.
