发表机构
Delft University of Technology; Soochow University; Arizona State University（代尔夫特理工大学; 苏州大学; 亚利桑那州立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过集合小胞DFT模拟揭示，碳化锆早期氧化中碳的分配强烈依赖温度，973 K以上升温促进链形成而非气化。
AI 中文摘要
在碳化锆氧化过程中，释放的碳可以留在氧化物下方或作为气体逸出，这使质量测量的解释复杂化。我们采用小胞集合方法，利用16条140皮秒的从头算分子动力学轨迹，在873-1273 K温度下、持续高氧通量并伴随气体移除的条件下进行模拟。净质量增加和总碳转移（进入气体或保留链）的平均速率遵循阿伦尼乌斯趋势。在973 K以上，气体逸出趋于平稳，而总碳转移增加。转移碳中保留在链中的比例从973 K时的40%上升到1273 K时的66%。40皮秒后的拟合表明碳转移速率随时间下降，尽管并非每条轨迹都如此。这些结果表明，早期氧化过程中的碳分配取决于温度，在973 K以上升高温度有利于链形成而非气化。
英文摘要
During zirconium carbide oxidation, liberated carbon can remain beneath the oxide or escape as gas, complicating the interpretation of mass measurements. We adapt the small-cell ensemble method using sixteen 140 ps ab initio molecular dynamics trajectories at 873-1273 K under a sustained high oxygen flux with gas removal. The average rates of net mass gain and total carbon transfer into gas or retained chains follow Arrhenius trends. Above 973 K, gas evolution levels off while total carbon transfer increases. The fraction of transferred carbon retained in chains rises from 40 % at 973 K to 66 % at 1273 K. Fits after 40 ps suggest declining carbon transfer rates over time, although not in every trajectory. These results show that carbon partitioning during early oxidation depends on temperature, with increasing temperature above 973 K favouring chain formation over gasification.
