The work is a continuation of research concerning the influence of intensive cooling of permanent mold in order to increase the casting
efficiency of aluminium alloys using the multipoint water mist cooling system. The paper presents results of investigation of crystallization
process and microstructure of synthetic hypereutectic alloys: AlSi15 and AlSi19. Casts were made in permanent mold cooled with water
mist stream. The study was conducted for unmodified silumins on the research station allowing the cooling of the special permanent probe
using a program of computer control. Furthermore the study used a thermal imaging camera to analyze the solidification process of
hypereutectic silumins. The study demonstrated that the use of mold cooled with water mist stream allows in wide range the formation of
the microstructure of hypereutectic silumins. It leads to higher homogeneity of microstructure and refinement of crystallizing phases and
also it increases subsequently the mechanical properties of casting.