First-principles thermodynamical calculations and experimental confirmation of the phase diagrams of ceramic systems

陶瓷体系相图的第一性原理热力学计算和实验确认

• 批准号: 18206067
• 负责人: TANAKA Isao
• 金额: $ 31.95万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-18206067/
• 关键词: ceramics; phase diagram calculation; first-principles calculation; thermodynamics; phase transition; 状態図計算; 比熱; 固溶体; 薄膜

Systematic first-principles thermodynamical calculations were performed to predict the phase boundary, phase transition, and compound formation in oxide binary systems. To confirm the theoretical results, experimental characterization was also conducted for a variety of specimens including supersaturated solid solutions. Computational methods for realistic thermodynamical simulations were developed on the basis of the experimentally obtained information.A combination of duster expansion technique, Monte Carlo simulations, and first-principles lattice statics and dynamics methods was used for the calculations. Specific heat was obtained from the lattice dynamics calculations, and free energy function was then derived from the integration. Using the duster expansion and Monte Carlo techniques, equilibrium structures and formation energies were predicted for possible phases in binary systems. The theoretical results were confirmed by experiments, such as x-ray diffraction and x-ray spectroscopy for ceramic specimens and the thin films of supersaturated solid solutions made by the pulsed laser deposition. As a result, atomic structures, thermodynamical properties, phase boundaries, phase transition behavior and compound formation were revealed for a variety of oxide binary systems. The examples include the theoretical prediction of the formation of new series of homologous phases in the Sn-O system and the determination of the local atomic structures in the ZnO-MgO, ZnO-Al_2O_3, Ga_2O_3-MnGa_2O_4 pseudo-binary systems.

进行系统的第一原理热力学计算来预测氧化物二元系统中的相界、相变和化合物形成。为了证实理论结果，还对包括过饱和固溶体在内的各种样品进行了实验表征。基于实验获得的信息，开发了用于实际热力学模拟的计算方法。计算中结合了喷粉展开技术、蒙特卡罗模拟以及第一性原理晶格静力学和动力学方法。通过晶格动力学计算获得比热，然后通过积分导出自由能函数。使用除尘器展开和蒙特卡罗技术，预测了双星系统中可能的相的平衡结构和形成能量。理论结果得到了陶瓷样品和脉冲激光沉积过饱和固溶体薄膜的X射线衍射和X射线光谱等实验的证实。结果，揭示了各种氧化物二元系统的原子结构、热力学性质、相界、相变行为和化合物形成。实例包括Sn-O体系中新系列同系相形成的理论预测以及ZnO-MgO、ZnO-Al_2O_3、Ga_2O_3-MnGa_2O_4伪二元体系中局域原子结构的确定。

项目成果

First principles calculations of-advanced nitrides and alloys

高级氮化物和合金的第一原理计算

• 发表时间: 2007
• 作者: I.;Tanaka
• 通讯作者: Tanaka

Debye temperature and stiffness of carbon and boron nitride polymorphs from first principles calculations

• DOI: 10.1103/physrevb.73.064304
• 发表时间: 2006-02
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: T. Tohei;A. Kuwabara;F. Oba;I. Tanaka

Free Energy Calculations of Precipitate Nucleation

沉淀成核的自由能计算

• 发表时间: 2007
• 期刊: Materials Science Forum 539-543
• 作者: Masayuki Nishida;Takao Hanabusa;Yasukazu Ikeuchi;Masayuki Nishida;西谷滋人;Shigeto R.Nishitani
• 通讯作者: Shigeto R.Nishitani

Microstructure of Mn-doped Ga_2O_3 epitaxial film on sapphire (0001) with room temperature ferromagnetism

室温铁磁性蓝宝石(0001)上Mn掺杂Ga_2O_3外延薄膜的显微结构

• 发表时间: 2006
• 期刊: J. Appl. Phys 101
• 作者: R.;Huang;H.;Hayashi;F.;Oba;I.;Tanaka
• 通讯作者: Tanaka

Vacancy effect on the precipitate nucleation in Fe-Cu alloy

空位对Fe-Cu合金中析出相形核的影响

• 发表时间: 2006
• 期刊: Proceedings for the 3rd International Conference of Multiscale Materials Modeling(Ed by P.Gumbsch)(Fraunfofer IRB Veralag) ISBN-13:978-3-8167-7206-4
• 作者: Masayuki Nishida;Takao Hanabusa;Yasukazu Ikeuchi;Masayuki Nishida;西谷滋人;Shigeto R.Nishitani;Shigeto R.Nishitani;Shigeto R.Nishitani;西谷滋人;Shigeto R.Nishitani
• 通讯作者: Shigeto R.Nishitani