(1. 中南大学材料科学与工程学院,长沙 410083;
2. 中南大学有色金属材料科学与工程教育部重点实验室,长沙 410083;
3. 中南大学有色金属先进结构材料与制备协同创新中心,长沙 410083)
摘 要: 通过删除晶界处不合理原子,修正可计算任意晶界能量的球形双晶模型,并将修正模型应用于计算金属Al中3类典型晶界的晶界能,分析模型的合理性和晶界能的晶界空间取向参数相关性。á011?对称倾斜晶界的计算结果表明:修正模型所构造的晶界结构更加稳定,所得晶界能与块状模型结果吻合更好。á001?扭转晶界和á011?非对称倾斜晶界的结果分别表明:取向差轴固定时,晶界能整体上随取向差角和晶界面倾斜角的增大而升高。综合上述3类晶界结果可知,晶界能与重位因子间不存在特定的相关性,不能基于重位因子预测晶界能的相对大小。
关键字: 晶界;晶界能;数值模拟;分子动力学;重位点阵
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials Science and Engineering,
Ministry of Education, Central South University, Changsha 410083, China;
3. Collaborative Innovation Center of Advanced Nonferrous Structural Materials and Manufacturing,
Central South University, Changsha 410083, China)
Abstract:The sphere bicrystal model for calculating the energy of an arbitrary grain boundary (GB) was corrected by deleting unreasonable atoms located at the boundary. This model was then applied to calculate the energies of three categories of GBs in Al to validate the modification, and used to investigate the dependencies of GB energy on GB parameters. The results for the á011? symmetrical tilt grain boundaries show that, compared to the original model, the modified model can obtain a more stable GB structure and a lower energy, which agrees better with that obtained by the block bicrystal model. The calculations for the á001? twist GBs and á011? asymmetric tilt GBs reveal a positive dependency of GB energy on misorientation angle and boundary inclination angle, respectively. The analysis results for these three types of GBs indicate that there is no specific relation between GB energy and coincidence factor. It is thus impossible to predict the relative GB energy values based solely on the coincidence factor.
Key words: grain boundary; grain boundary energy; numerical simulation; molecular dynamics; coincidence site lattice