The research is devoted to development of experimental foundry pattern equipment, allowing to obtain two or more castings in a sand-loam mould; these casting are crystallized via individual cooling procedures within structurally sensitive intervals (dendrite, eutectic crystallization and recrystallization). Influence of scale factor is excluded in this case and it makes possible to obtain control and pilot castings, which have equal sizes; influence of chemical composition is excluded as well, because all castings located in a mould have common gating and feeding system. It provides the same temperature and casting speed for two or more castings in one mould with different compositions and technological properties of moulding mixtures for each of the comparing castings. Thereby, variable cooling rate, which is individual for each casting obtained in the experimental mould, remains the main factor having influence on forming of structure, mechanical and operating properties of cast metal. Possibility of investigation of rise of mechanical and operating properties of castings owing to only adjusting of cooling rate without use of alloying and modification appears in this case. Increase of the cooling rate in local temperature-time crystallization intervals is provided by blowing with cooling gases which are fed in the mould via the stand (receiver). Retarding of cooling rate occurs as a result of mould heating during thermal oxidizing destruction of exothermal carbon-containing additives which are specially introduced in the facing layer of moulding mixture. It is necessary to mention that variation of cooling rate can be conducted via the procedures which are individual for each casting located in the experimental mould. Developed and fabricated experimental foundry equipment was used for testing of the concrete cooling procedures of thin-walled castings made of grey cast iron. Pressure of cooling compressed air, which was fed during the process, and amount of exothermal carbon-containing additive, which was introduced in composition of the facing layer of moulding mixture for pilot castings were varied. As a result, the efficient cooling procedure was selected; it allowed to rise tensile strength for the pilot casting by 13 %, to improve cast iron quality (quality index) by 23 % and to increase structure dispersity of primary austenite by 21 % without introduction of alloying elements and modifiers in cast iron composition.
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