Volgograd State Technical University, Volgograd, Russia:

N. A. Kidalov, Dr. Eng., Prof., Head of the Dept. of Machinery and Technology of Foundry (MTF)
N. V. Belova, Lecturer, Dept. of MTF
A. A. Belov, Cand. Eng., Lecturer, Dept. of MTF, e-mail: aa-belov@bk.ru
A. S. Adamova, Cand. Eng., Associate Prof., Dept. of MTF

The chemical and physical processes that occur during high-temperature heating of carbon-containing additives are studied in order to develop an effective composition, whose components destruction will lead to a violation of the integrity of the binder film and a decrease in the residual strength of liquid-glass mixtures, and hence an improvement in the knock-out of molds and cores in the conditions of obtaining castings from alloys of ferrous metals. Carboncontaining materials used in foundry production, the destruction of which proceeds in different temperature ranges, have been studied. The methods of thermogravimetric and differential thermal analyzes have been used to study the processes that tale place with materials under study when heated to temperatures comparable to the actual operating conditions of casting cores in direct contact with liquid and solidifying metal in the mold. As a result of the analysis of the considered carbon-containing materials, the temperature intervals of destruction were revealed, which made it possible to predict their effect on the structure of sodium silicate (binder) on the refractory filler and the residual strength of mixtures in order to improve the knock-out of steel castings. Obtaining high-quality casting molds and cores depends on the technological, hydraulic and mechanical characteristics of the mixture, therefore, additional studies were carried out, the results of which revealed the compliance of the determined properties of the studied samples with the requirements for molding and core sand mixtures on a liquid-glass binder.

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