Purpose: The first aim of investigations was the reduction of grain size and unification of structure for pure Al casting by introduction of small amount of inoculant (less than obligatory standard PN-EN 573-3, which concerning about aluminium purity) and with electromagnetic field. The second aim was to determination of electromagnetic field influence on morphology of graphite in cast iron ingots, which were poured with variable founding parameters. Design/methodology/approach: To investigations of pure Al and grey cast iron were used two types of rotate electromagnetic field i.e. without reversion (WPM) and with reversion and with a pause between following changes of electromagnetic field direction (IRPM). Findings: The results of investigations and their analysis show possibility of effective inoculation of pure aluminium structure by use of influencing of stirring electromagnetic field into metal during solidification and inoculation by introducing AlTi5B1 inoculant into liquid aluminium. Moreover results of studies show advantageous influence of electromagnetic field on graphite morphology. Research limitations/implications: In further researches, authors of this paper are going to apply his method of inoculation in industrial tests. Practical implications: The work presents a method of structure refinement which is particularly important in continuous and semi – continuous casting. In pure metals large columnar crystals zone result in forces extrusion rate reduction and during the ingot rolling delamination of external layers can occur. Thus, in some cases ingot skinning is needed, which rises the production costs. Whereas morphology of graphite in cast iron ingots for automobile industry is very important in viewpoint of wear resistance. Originality/value: Contributes to research on size reduction in pure metals structure and forming of graphite in cast iron.