Computer simulation of morphology and growth velocity of crystal in Fe-B melt under super-rapid cooling conditions

Crystallization of a binary Fe-B melt is studied by computer simulation with regard for the temperature dependence of the diffusion coefficient and the possibility of nonequilibrium alloying-component entrapment (i.e., the dependence of the distribution coefficient on the ratio of the V crystallization rate to the VD diffusion rate). The effect of high cooling rates of the melt on the dendritic morphology is analyzed. The dependence of the dendrite-tip growth rate on the melt supercooling is obtained. At a high supercooling a morphological transition is shown to occur, which is related to the change from a diffusion to a diffusion-free dendrite growth mode