The paper presents the optimization of master alloy amount for the high nodular graphite yield (80-90%) in cast iron obtain in lost foam process. The influence of the gating system configuration and the shape of the reaction chamber, the degree of spheroidisation cast iron was examined. Research has shown that the, optimal of master alloy amount of 1.5% by mass on casting iron. The degree of spheroidisation is also influenced by the gating system configuration. The best spheroidisation effect was obtained for liquid cast iron was fed into the reaction chamber from the bottom and discharged from the top.

This paper presents a technology of ductile cast iron obtain by lost foam process with use of inmold method. Spheroidization was carried out using master alloy in an amount of 1.5% by mass on casting iron.Research the influence of the gating system configuration and the shape of the reaction chamber, the degree of spheroidization cast iron, which estimated based on the shape of the graphite. Research have shown that the greatest impact on the degree of spheroidization has cast the infusion position relative to the casting inlet and the reaction chamber, and the shape of the reaction chamber.Keywords: nodular cast iron (ductile cast iron), inmold method, lost foam casting, innovative casting technologies, reaction chamber W pracy przedstawiono technologię otrzymywania odlewów z żeliwa sferoidalnego metodą inmold z wykorzystaniem procesu pełnej formy. Sferoidyzację prowadzono z użyciem zaprawy sferoidyzująco-modyfikującej w ilości 1,5% na masę sferoidyzowanego żeliwa.Przeprowadzono badania wpływu konfiguracji układu wlewowego oraz kształtu komory reakcyjnej na stopień sferoidyzacji żeliwa, który określono na podstawie wskaźnika kształtu grafitu. Badania wykazały, że największy wpływ na stopień sferoidyzacji żeliwa ma położenie wlewu doprowadzającego względem odlewu i komory reakcyjnej, oraz kształt komory reakcyjnej.

The current work presents and describes the test bench for analyzing the lost foam process, especially measuring of the pressure of gases in the gas gap and continuous measuring of the rate of rise of the bath level when pouring the liquid metal into the mould. A series of preliminary research was carried out on the bench which was aimed at determining the influence of the basic parameters of the process, i.e. the density of the styrofoam pattern, thickness of the refractory coating applied on the pattern, kind of the alloy and the temperature of pouring on the mould cavity by the liquid metal and the pressure of gases in the gas gap.

Small additions of Cr, Mo and W to aluminium-iron-nickel bronze are mostly located in phases κi (i=II; III; IV),and next in phase α (in the matrix) and phase γ2. They raise the temperature of the phase transformations in aluminium bronzes as well as the casts’ abrasive and adhesive wear resistance. The paper presents a selection of feeding elements and thermal treatment times which guarantees structure stability, for a cast of a massive bush working at an elevated temperature (650-750°C) made by means of the lost foam technology out of composite aluminium bronze. So far, there have been no analyses of the phenomena characteristic to the examined bronze which accompany the process of its solidification during gasification of the EPS pattern. There are also no guidelines for designing risers and steel internal chill for casts made of this bronze. The work identifies the type and location of the existing defects in the mould’s cast. It also proposes a solution to the manner of its feeding and cooling which compensates the significant volume contraction of bronze and effectively removes the formed gases from the area of mould solidification. Another important aspect of the performed research was establishing the duration time of bronze annealing at the temperature of 750°C which guarantees stabilization of the changes in the bronze microstructure - stabilization of the changes in the bronze HB hardness.

The article presents the results of the research on the influence of the shape of reaction chamber on spheroidisation of cast iron produced with use of the inmold method. The amounts of nodular graphite precipitates in castings produced with the use of different reaction chambers have been compared.