As part of the final thesis "Manufacturing and characterization of modified lamellar graphite cast iron," virtual testing and design of the investigated flake cast iron were systematically performed using the gravity casting technique in disposable molds made of a bentonite-sand mixture. The casting technology was successfully done and the test casting was carried out. The calculation of the casting processes included: pouring, cooling, solidification, and the calculation of defects due to shrinkage, mold erosion, cooling rates, and temperature fields in the casting and mold, as well as the calculation of ferrite and pearlite in the FGI matrix and mechanical properties. The design and manufacture of a pattern, molding, synthesis of two FGI cast irons, alloying and inoculation, and casting of the test casting were successfully carried out with the simultaneous use of simple thermal analysis. The characterization of the obtained samples included the precise determination of the chemical composition and metallographic analysis of areas that solidify at high, medium, and low cooling rates. We found, that at high cooling rates, the tested cast irons 1 and 2 solidify white. At medium cooling rates, the solidification processes was gray. Furthermore, it was found that, in addition to the chemical composition of the cast iron, the nucleation potential, which is related to the effectiveness of nucleation, also strongly influenced on the formation of graphite. The graphite particles obtained, depending on their fineness, shape, size and distribution, in conjunction with the elements that stabilize pearlite, have a dominant influence on the course of the eutectoid transformation.
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