EFFECTS OF SURFACE-ENERGY AND KINETICS ON THE GROWTH OF NEEDLE-LIKE DENDRITES

In the framework of the exact nonlocal thermal conductivity problem, the effect of anisotropy both of surface energy and kinetics on the selection of velocity and direction of two-dimensional dendritic growth has been studied analytically. At small undercooling the growth is mainly governed by anisotropy of the surface energy, while at large undercooling it may be governed by kinetic effects. In the case where the directions of growth determined by surface energy and kinetics coincide, the increase in any anisotropy results in an increase of growth velocity. When these directions do not coincide, the direction of growth varies with undercooling. © 1990.