Ab initio Based Modeling of Radiation Effects in Multi-Component Alloys: Final Scientific/Technical Report
Ab initio Based Modeling of Radiation Effects in Multi-Component Alloys: Final Scientific/Technical Report
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基于从头算的多组分合金辐射效应建模：最终科学/技术报告
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
D. Morgan
中科院分区：
文献类型：
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作者：
D. Morgan
该项目于2006年3月13日开始，分配了三年，并从2009年3月13日延长一年至2010年3月12日。目前已完成48个月中的48个月。该项目的重点是使用从头计算方法来深入了解Ni-Fe-Cr合金中的辐射诱导偏析（RIS）。该项目取得了以下主要成就：开发了一个大型从头算能量学数据库，可供许多研究人员在未来使用，以增加对该系统的理解。例如，我们的第一个计算显示了显着的稳定效果的铬-铬间隙哑铃在镍。·对于稀Cr和Fe的Ni-Cr和Ni-Fe的空位和间隙扩散常数的预测。这项工作包括推广广泛使用的多频模型，利用从头推导的能量学和热力学。·从空位和间隙机制预测RIS的定性趋势，表明两种类型的缺陷通量在相反方向上驱动Cr RIS。·Ni-Cr中空位机制扩散的详细动力学Monte Carlo建模作为Cr浓度的函数。结果表明，铬含量可以有显着的影响RIS。·开发定量RIS传输模型，包括热力学因素和边界条件的模型。«少
The project began March 13, 2006, allocated for three years, and received a one year extension from March 13, 2009 to March 12, 2010. It has now completed 48 of 48 total months. The project was focused on using ab initio methods to gain insights into radiation induced segregation (RIS) in Ni-Fe-Cr alloys. The project had the following key accomplishments • Development of a large database of ab initio energetics that can be used by many researchers in the future for increased understanding of this system. For example, we have the first calculations showing a dramatic stabilization effect of Cr-Cr interstitial dumbbells in Ni. • Prediction of both vacancy and interstitial diffusion constants for Ni-Cr and Ni-Fe for dilute Cr and Fe. This work included generalization of widely used multifrequency models to make use of ab initio derived energetics and thermodynamics. • Prediction of qualitative trends of RIS from vacancy and interstitial mechanisms, suggesting the two types of defect fluxes drive Cr RIS in opposite directions. • Detailed kinetic Monte Carlo modeling of diffusion by vacancy mechanism in Ni-Cr as a function of Cr concentration. The results demonstrate that Cr content can have a significant effect on RIS. • Developmentmore » of a quantitative RIS transport model, including models for thermodynamic factors and boundary conditions.« less