Chuvash State University (Cheboksary, Russia)

I. E. Illarionov, Dr. Eng., Prof, Head of the Chair “Metal science and metallurgical processes”, e-mail: tmilp@rambler.ru

Siberian Federal University (Krasnoyarsk, Germany)
T. R. Gilmanshina, Cand. Eng., Associate Prof., e-mail: gtr1977@mail.ru
A. A. Kovaleva, Cand. Eng., Associate Prof.
V. A. Borisyuk, Post-Graduate

The purpose of this work is to investigate the thickness of the cover and penetrating layers, depending on the content of mechanically activated graphite in the coating filler, applied to cold-hardening mixtures based on liquid glass and resins. In the course of the work it was found that with the increase in the content of activated graphite (from 0 to 100%) in the filler composition for all investigated mixtures, the thickness of the coating layer decreases (for liquid-glass mixtures on quartz sands 3K₃O₂016 and 2K₁O₃03 — from 0,59 to 0,26 and from 0,56 to 0,12, for cold-hardening mixtures on ecolite and alphabond resins — from 0,56 to 0,1 mm and from 0,46 to 0.06 mm, respectively), and the penetrating increases (for liquid-glass mixtures on quartz sand 3K₃O₂016 and 2K₁O₃03 — from 0,28 to 2,04 and from 0,28 to 2,41, for cold-hardening resins on ecolite and alphabond — with 0,28 to 1,74 mm and from 0,63 to 0,93 mm, respectively). The most optimal ratio of natural and activated graphite to the fi ller of self-drying non-stick coatings based on cryptocrystalline graphite can be considered 50 : 50. In this case, large particles of natural graphite will remain on the surface of the mold, forming a cover layer, and fi ne particles of activated graphite will penetrate in the pores of the mold, creating a penetrating layer. The roughness of the casting will be determined by the particle size of the graphite in the cover layer of the coating. The results of the research are recommended to be used in foundries for the production of castings.

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