The presence of the chunky graphite is unwanted in the cast iron with the spheroidal graphite for this significantly lowers the properties of

the ductile iron. This shape of the graphite is formed as the result of the slow cooling rate of the castings with large thermal point and also

due to the presence of the elements which suppress the formation of the spheroidal graphite and support formation of the chunky graphite.

The spheroidal graphite present in the ductile iron assures the excellent mechanical properties, while the chunky graphite significantly

reduces those properties of the ductile iron. Therefore it is of importance to assume conditions under which prevented is the formation of

the chunky graphite. The casts were carried out under the conditions of the regular operation of the foundry and tested were various types

of modifiers and inoculators and also pre-inoculators containing the elements suppressing the formation of the chunky graphite (Al, Sb a

Ba). Applied were also the chromium breaker core to suppress the formation chunky graphite which was present in the structure in the

places after the feeders elimination. As whole, executed were eight casts with various types of the modifiers and inoculators.

Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process. Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting +5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5% bentonite) and used as a part of charge into the electric induction furnace. It was found that addition of briquettes has had an influence of a chemical composition of cast iron above all on content of sulphur, phosphorus and silicon. It was not reflected in decrease in tensile strength and in microstructure. Yield of metal from briquettes was not lower then 70%.

Homogeneity of die castings is influenced by wide range of technological parameters as piston velocity in filling chamber of die casting machine, filling time of mould cavity, temperature of cast alloy, temperature of the mould, temperature of filling chamber, surface pressure on alloy during mould filling, final pressure and others. Based on stated parameters it is clear, that main parameters of die casting are filling time of die mould cavity and velocity of the melt in the ingates. Filling time must ensure the complete filling of the mould cavity before solidification process can negatively influence it. Among technological parameters also belong the returning material, which ratio in charge must be constrained according to requirement on final homogeneity of die castings. With the ratio of returning material influenced are the mechanical properties of castings, inner homogeneity and chemical composition.