Evaluation of grain boundary segregation based on atomistic/electronic nonempirical analysis

基于原子/电子非经验分析的晶界偏析评价

• 批准号: 21760090
• 负责人: TSURU Tomohito
• 金额: $ 1.83万
• 依托单位: Japan Atomic Energy Agency
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21760090/
• 关键词: 材料設計; プロセス; 物性; 評価; 粒界偏析; 不純物クラスター; Bragg-Williams近似; 不純物拡散; 状態遷移解析; 粒界拡散

The segregation of impurities were investigated by Bragg-Williams approximation combined with first principle density functional theory calculations. The segregation tendencies of various elements observed in reactor pressure vessels were considered and the interaction characteristics between □-Fe and each impurity element were estimated by mean field approximation. Stable N-atom impurity clusters were subsequently chosen to evaluate the changes in free energy for clustering. These calculations show that Cu and Mn impurities embedded in □-Fe are more stable when they are in the segregated state. Conversely, Nb and Ta are stable in the separately solute state. The present estimates provide reliable suggestions for the segregation characteristics.

通过布拉格-威廉姆斯近似结合第一原理密度泛函理论计算研究了杂质的偏析。考虑了反应堆压力容器中观察到的各种元素的偏析倾向，并通过平均场近似估计了□-Fe与各杂质元素之间的相互作用特征。随后选择稳定的 N 原子杂质簇来评估簇自由能的变化。这些计算表明，嵌入在□-Fe中的Cu和Mn杂质在处于偏析状态时更加稳定。相反，Nb和Ta在单独溶质状态下是稳定的。目前的估计为分离特征提供了可靠的建议。

项目成果

Nanoscale contact plasticity of crystalline metal : Experiment and analytical investigation via atomistic and discrete dislocation models

晶体金属的纳米级接触塑性：通过原子和离散位错模型进行实验和分析研究

• 发表时间: 2010
• 期刊: Acta Materialia 58
• 作者: T.Tsuru;Y.Kaji;Y.Shibutani
• 通讯作者: Y.Shibutani

Grain Boundary Characteristics Evaluation by Atomistic Investigation Methods

通过原子研究方法评估晶界特征

• 发表时间: 2010
• 期刊: Proceedings of MRS 2009 Fall Meeting (掲載決定)
• 作者: Y.Kaji;T.Tsuru;Y.Shibutani
• 通讯作者: Y.Shibutani

Ab initio calculations of Fe–Ni clusters

• DOI: 10.1016/j.commatsci.2009.03.012
• 发表时间: 2009-08
• 期刊: Computational Materials Science
• 影响因子: 3.3
• 作者: T. Nakazawa;T. Igarashi;T. Tsuru;Y. Kaji

Atomistic modeling of dislocation-grain boundary process

位错-晶界过程的原子建模

• 发表时间: 2010
• 作者: T.Tsuru

Atomistic simulations of strain localization in irradiated polycrystalline metals

辐照多晶金属应变局部化的原子模拟

• 发表时间: 2010
• 作者: T.Tsuru;Y.Kaji;et al.
• 通讯作者: et al.