Equiaxed dendrite solidification in supermodel melts

摘要

The growth of equipped dendrites from a pure supermodel melot is examined. We propose modifications to the classical Ivantsov theory that allow for consideration of multile interacting dendrites. The modified theory revelas the existence of a steady-state dendritic solidification mode in a frame of reference moving with the dendrite tip. This regime should be valid from the onset of nucleation to the commencement of time-dependent coarsening when the mass of the solid becomes comparable to the liquid mass in the solidification chamber. This grime is characterized by a reduced (relative to the signal dendrite case) heat flux leading to slower solidification rates, but with the same level of superceding. We study the effects of the relative proximity and number of interacting dendrites through a numerical example of solidification of succinonitrile, a common material use din many experiments. The data show that the model predicts a new steady growth regime that is different than the steady growth law of a single dendrite as described by Ivantsov theory.