Extended thermodynamical analysis of a motion of the solid-liquid interface in a rapidly solidifying alloy
Extended thermodynamical analysis of a motion of the solid-liquid interface in a rapidly solidifying alloy
复制标题
DOI：
10.1103/physrevb.65.144103
复制
发表时间：
2002-03
影响因子：
3.7
通讯作者：
P. Galenko
中科院分区：
文献类型：
--
作者：
P. Galenko
在推广的不可逆热力学@D. Jou，J. Casas-Vazquez，and G. Lebon，Rep. Prog.《物理学》51，1005 ~1988！62、1035 ~1999年！#提出了固-液界面运动的分析。除了Onsager和Prigogine的经典不可逆热力学的形式主义，一个独立的热力学变量的空间扩展通过引入溶质扩散通量与扩展的热力学方法局部非平衡过程的一致性。考虑到快速凝固前沿运动，当晶体生长速度为溶质扩散速度的量级甚至更大时，模型采用固液界面和液相内部的局部非平衡。考虑到溶质在相界面上的扩散速度和溶质在体相系统中扩散传播的有限速度，导出了溶质通量、共轭驱动力、凝固吉布斯自由能变化和液相线斜率的方程。讨论了本模型预测的结果，并与实验数据的模型预测进行了比较分析。
On the basis of extended irreversible thermodynamics @D. Jou, J. Casas-Vazquez, and G. Lebon, Rep. Prog. Phys. 51, 1005 ~1988!; 62, 1035 ~1999!# an analysis of the solid-liquid interface motion is presented. In addition to the formalism of the classic irreversible thermodynamics of Onsager and Prigogine, a space of independent thermodynamic variables is extended by introducing the solute diffusion flux in consistency with the extended thermodynamic approach to local nonequilibrium processes. Considering the rapid solidification front motion, when the crystal growth velocity is of the order or even greater than the speed for solute diffusion, a local nonequilibrium at the solid-liquid interface and inside bulk liquid is adopted by the model. Taking into account the solute diffusive speed at the phase interface and the finite speed of solute diffusive propagation in bulk system, the equations for thermodynamical fluxes, conjugated driving forces, the Gibbs free energy change on solidification, and liquidus line slope are derived. A discussion of the outcomes predicted by the present model and a comparative analysis of the model predictions with experimental data are made.