METHOD OF DISPERSING SILICON IN A SILUMIN MELT CRYSTALLIZING IN AN INHOMOGENEOUS MAGNETIC FIELD

This paper deals with the problem of controlling the process of silicon dispersion in a crystallizing silumin melt by means of an inhomogeneous permanent magnetic field. It is established that during crystallization of the silumin melt in an inhomogeneous permanent magnetic field, diffusive and convective flows of silicon are activated near the crystallization front. A physical and mathematical model of the process of influence of an inhomogeneous permanent magnetic field on secondary silicon ions near the crystallization front is proposed. The total flux of silicon atoms (ions) caused by two mechanisms is calculated: the first is classical diffusion caused by the silicon concentration gradient at the crystal-melt boundary; and the second is the force effect of an inhomogeneous magnetic field on magnetic dipoles of silicon near the crystallization front. Microstructural analysis of silumin specimen slits obtained during their crystallization in an inhomogeneous permanent magnetic field confirms the effect of this field on the formation of a given structure.