Volgograd State Technical University (Volgograd, Russia):

V. A. Gulevskiy, Cand. Eng., Associate Prof., Dept. of Machines and Technology of Foundry Production, E-mail: mitlp@vstu.ru
S. N. Tsurikhin, Associate Prof., Dept. of Machines and Technology of Foundry Production
V. V. Gulevskiy, Post-graduate Student, Dept. of Theoretical Mechanics
N. Yu. Miroshkin, Post-graduate Student, Dept. of Machines and Technology of Foundry Production

Research is devoted to the influence of the technological method of modifying gray cast iron for the manufacture of steel casting molds. Heavy operation imposes stringent requirements both on the design of molds and on the materials from which they are made. They reliably withstand the effects of steel poured into them, having a temperature of 1600–1700 °C, thermal shock, which is directly proportional to this temperature, as well as significant effects of cyclic thermal stress and deformation. Specific operating conditions of molds (high heating temperature, their installation on movable and stationary ditches, intensive traffic flows, etc.) complicate the necessary processes directly during their operation. Modeling geometric shapes on a scale of geometric similarity 1:10. Tests were carried out on molds cast from cast iron for consumable electrodes, modified with ferrosilicon (FS65 GOST 1415-93), primary aluminum A99 (GOST 11069-2001), vanadium slag (SHVD-1 TU14-11-178-86), FSB-30) and silicomishmetal (SIMISH-1). These modifiers were chosen for modification, as they are widely used in production. Thus, the conducted studies of the nature of the deformation of the walls of the molds and the stress-strain state on models made of gray and modified cast iron make it possible to assess the advantages and disadvantages of the resulting structure and shape of graphite. Further, the methods of the rational formula of the outer surface of profiled and sheet molds are used, having predetermined the nature of destruction in advance. The use of thin-walled used rational forms can significantly reduce their specific consumption. The study of the quality of the metal cast into the experimental curved outer surface showed that the macrostructure of the metal of the experimental and ordinary ingots is the same.
The work was attended by N.V Markina, senior lecturer at the Dept. of Machines and Foundry Technology, Volgograd State Technical University.

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