Flow-induced changes of the morphological stability in directional solidification: localized morphologies

Abstract

Steady, two-dimensional cellular convection is impressed upon a solid-liquid interface undergoing directional solidification. When the wave length 27r / a of the convection is very long compared to that, 27r / ß, of the morphological instability, the interface is sheared by "parallel" remote flow periodic in the flow direction.When the shear is taken to be constant instead of spatially periodic, a new formulation shows how a whole family of shear flows can be analyzed in a common way and how the physical mechanisms can be understood.When

Solidification microstructures and solid-state parallels: Recent developments, future directions

“…Such instabilities have been analyzed theoretically for the case of directional solidification [211][212][213]. It has been found that the solidification front exhibits slow, spatio-temporal dynamics when the wavelength of the cellular convection is far longer than that of the morphological cells.…”

Influence of Vibration on Morphology of Front During the Directional Solidification

“…В работах [8][9][10] показано их влияние на макроструктуру и морфологическую устойчивость фронта. Так в [10] показано, что гравитационная кон-векция заметно снижает критическую скорость потери устойчиво-сти плоского фронта, а в [9] получена общая диаграмма уменьше-ния области устойчивого роста при увеличении скорости потока расплава.…”

Morphological instability of interface, cell and dendrite during directional solidification under strong magnetic field

“…It has been shown in the classical work by Mullins and Sekerka [1] that the origin of this instability of the interface is related to the dependence of phase change temperature on solute concentration by considering the isotropy interface properties. Later, there appeared a great number of works that investigated the effect of solute convection, forced flows, and other factors on the morphological instability [2,3]. The effect of the slightly anisotropic surface tension and kinetics on morphological stability was studied by Cahn [4] and Coriell and Hardy [5].…”