Jugdutt Bernadine A, Ofori-Opoku Nana, Provatas Nikolas
Department of Physics, Centre for the Physics of Materials, McGill University, Montreal, QC, Canada.
Department of Materials Science and Engineering, McGill University, Montreal, QC, Canada.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Oct;92(4):042405. doi: 10.1103/PhysRevE.92.042405. Epub 2015 Oct 21.
This work uses Ginzburg-Landau theory derived from a recent structural phase-field-crystal model of binary alloys developed by the authors to study the roles of concentration, temperature, and pressure on the interfacial energy anisotropy of a solid-liquid front. It is found that the main contribution to the change in anisotropy with concentration arises from a change in preferred crystallographic orientation controlled by solute-dependent changes in the two-point density correlation function of a binary alloy, a mechanism that leads to such phenomena as solute-induced elastic strain and dislocation-assisted solute clustering. Our results are consistent with experimental observations in recent studies by Rappaz et al. [J. Fife, P. Di Napoli, and M. Rappaz, Metall. Mater. Trans. A 44, 5522 (2013)]. This is the first PFC work, to our knowledge, to incorporate temperature, pressure, and density into the thermodynamic description of alloys.
这项工作使用了作者最近开发的二元合金结构相场晶体模型推导的金兹堡-朗道理论，以研究浓度、温度和压力对固液界面能各向异性的作用。研究发现，各向异性随浓度变化的主要贡献源于二元合金两点密度相关函数中溶质依赖变化所控制的择优晶体取向变化，这一机制导致了诸如溶质诱导弹性应变和位错辅助溶质聚集等现象。我们的结果与拉帕兹等人[J. 法伊夫、P. 迪·纳波利和M. 拉帕兹，《金属与材料学报A》44, 5522 (2013)]近期研究中的实验观察结果一致。据我们所知，这是第一项将温度、压力和密度纳入合金热力学描述的相场晶体工作。
