two-phase state of crystallite and grain boundary in nanocrystalline gold stabilized by vacancy-type defects with compositional concentration

纳米晶金中微晶和晶界的两相态由具有成分浓度的空位型缺陷稳定

• 批准号: 22560656
• 负责人: TANIMOTO Hisanori
• 金额: $ 2.83万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2010
• 资助国家: 日本
• 起止时间: 2010 至 2012
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-22560656/
• 关键词: ナノ物性; ナノ材料; 金属物性; 超微細多結晶組織; 結晶粒界; 原子空孔; 格子定数; 力学特性; 格子欠陥; ナノ結晶; ナノ物性; ナノ材料; 金属物性; 超微細多結晶組織; 結晶粒界; 原子空孔; 格子定数; 力学特性; 格子欠陥; ナノ結晶

We found that nanocrystalline gold (ultrafine polycrystalline with the mean grain size below a few tens nm, n-Au, hereafter) shows characteristic behaviors. We have proposed that a two-phase state with crystallite phase and surrounding grain boundary phase are in quasi-equilibrium. From the anelastic measurement, an increase in grain boundary anelasticity was found at around 200 K. The x-ray diffraction measurement showed that the lattice constant at room temperature was smaller by about 0.05% from that of the conventional polycrystalline gold (poly-Au) and the temperature change of the lattice constant became slightly moderate at around 200 K. These propertie s were recovered to those of poly-Au after grain growth by annealing. It is indicated that the state of the grain boundaries of n-Au is different from that of poly-Au and the lattice contraction play an important role on the quasi-equilibrium of two-phase state.

我们发现，纳米晶金（超平均晶粒尺寸低于几十nm，N-AU，以下称）显示出特征性的行为。我们已经提出，具有结晶石相和周围晶界相的两相状态在准平衡中。 From the anelastic measurement, an increase in grain boundary anelasticity was found at around 200 K. The x-ray diffraction measurement showed that the lattice constant at room temperature was smaller by about 0.05% from that of the conventional polycrystalline gold (poly-Au) and the temperature change of the lattice constant became slightly moderate at around 200 K. These propertie s were recovered to those of poly-Au after grain growth by annealing.据表明，n-AU的晶界状态与poly-au的状态不同，而晶格收缩在两相状态的准平衡中起重要作用。