CRYSTALLIZATION OF MULTICOMPONENT MELTS UNDER NONUNIFORM CONDITIONS

Evolution processes proceeding in the course of solidification of sing le-and multi-components melts in heterogeneous systems are investigate d. A set of equations describing the kinetics of the crystallization p rocess during removal of heat from boundary of the system is derived a nd solved. As a result of solution of the system, the equation for mot ion of a new phase crust, the distribution function for disperse parti cles in terms of their size and composition and a law of variation in the mean radius of disperse particles in space are obtained. It is sho wn that during crystallization of a multi-phase and multicomponent mel t under nonuniform conditions the phase composition of an final sample can differ in its various points. General equations describing the ph ase co-existence region are derived. (C) 1998 Elsevier Science Ltd. Al l rights reserved.