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.

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.

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.