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.

This work presents the technology of making foam plastics patterns used in casting as well as the final shaping stand. The analysis of the sintering process was carried out aiming at determining the influence of the pressure and the time of sintering on the flexural strength properties. The analysis of the research results confirmed that when the sintering pressure grows to the value of Pa =1,7 bar the flexural strength also increases, when the pressure value is higher than that, the degradation of the material takes place and the strength properties decrease.

This work presents the analysis of the final shaping process of the patterns aimed at determining the influence of the pressure and the time of sintering on the resistance to bending. The analysis of the research results proved that when the pressure of the sintering rises and reaches Ps=2.1 bar the resistance to bending increases, above this level of the pressure the resistance value starts decreasing. The time of styrofoam sintering at which the highest bending resistance values were obtained is ts=90 s. When the sintering pressure is less than 2 bar prolongation of the time of sintering over 90 s causes a slight increase in the resistance, however, at higher pressures prolongation of the time of sintering causes submelting of the styrofoam pattern.

The article presents analysis of the influence of ingate size on the Lost Foam casting process. In particular, analysis of simulation tests has been carried out to determine the ingate size influence on the rate of filling of the mould cavity, pressure in the gas gap and size of the gas gap. A specially prepared mathematical model of the process and an original calculation algorithm were used in simulation tests of full-mould casting. The tests have indicated that the increase of the ingate size results in the increase of filling rate and increase of pressure of gases in the gas gap. However, significant influence on mould cavity filling occurs only when the ingate size is less than ~1 cm2.

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The article presents an analysis of the applicability of the Replicast CS process as an alternative to the investment casting process,

considered in terms of the dimensional accuracy of castings. Ceramic shell moulds were based on the Ekosil binder and a wide range of

ceramic materials, such as crystalline quartz, fused silica, aluminosilicates and zirconium silicate. The linear dimensions were measured

with a Zeiss UMC 550 machine that allowed reducing to minimum the measurement uncertainty.

Presented are results of a preliminary research on determining a possibility to use microwave radiation for drying casting protective

coatings applied on patterns used in the lost foam technology. Taken were measurements of permittivity εr and loss factor tgδ at 2.45 GHz,

as well as attempts were made of microwave drying of a protective coating based on aluminium silicates, applied on shapes of foamed

polystyrene and rigid polymeric foam. Time and results of microwave drying were compared with the results obtained by drying at 50 °C

by the traditional method commonly used for removing water from protective coatings. Analysis of the obtained drying kinetics curves

demonstrated that selection of proper operation parameters of microwave equipment permits the drying time to be significantly shortened.

Depending on kind of the pattern material, drying process of a protective coating runs in a different way, resulting in obtaining different

quality of the dried coating.

The article presents investigation results of the effect of sand fluidization on the structure and mechanical properties of AlSi9 aluminum alloy. Castings were made by lost foam casting process with sand fluidization in mold at the stages of their solidification and cooling. Sand fluidization was achieved by blowing sand bed with compressed air in a foundry container. The metallographic study was carrying out on samples cut from different sections of the castings. Mechanical properties were determined on specimens made from cast samples. Microstructural analysis showed that sand fluidization increases the cooling rate, as a result, the main microstructural components of the alloy – SDAS, eutectic silicon and needles of the rich-iron phase – decrease. Moreover, in different sections of the casting structure is more uniform. With an increasing the air flow rate, a greater refinement of the structure is observed. Through the use of sand fluidization, the mechanical properties of LFC aluminum alloys increase to the level of gravity die castings.

The aging granulate is to activate the blowing agent during the manufacturing process to granulate models can re-expand and shape the

model of well-sintered granules, smooth surface and a suitable mechanical strength.

The article presents the results of studies which aim was to determine the optimum time for aging pre-foamed granules for pre-selected

raw materials.

The testing samples were shaped in an autoclave, with constant parameters sintering time and temperature. Samples were made at 30

minute intervals. Models have been subjected to flexural strength and 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.

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.