Autors: Buchkova, G. M., Petrov, K. L., Zagorski, M. H., Kandeva, M. K., Mihaylov, A. M.
Title: GEOMETRICAL AND PHYSICO-MECHANICAL PARAMETERS OF REFRACTORY GRAPHITE COATINGS, USED IN FOUNDRY SAND MOULD AND CORES
Keywords: coatings, foundry, graphite, moulds, refractory

Abstract: The main purpose of this publication is to present the difference between the penetration of the graphite refractory coating in the sand mould/core considering the different grain size of the graphite particles – 60, 80, 100 and 120 microns, used for the production of graphite refractory coating. The second focus is compare the penetration with the microhardness, roughness, friability and gas permeability of a sand core, coated with graphite coating consisting different grain size of graphite. Special attention is paid to refractory coatings, and in particular those with graphite filler. Refractory coating applied on sand mould and core is responsible for the surface of the final casting. Sintering defect appears when metal penetrates in the sand mould/core. This defect can be avoided by using the right refractory coating. But our research is showing that not only the chemical parameters are important but also geometrical and physical once. The connection between the dimensions of the graphite particles and the penetration of the coating is found. The penetration of the coating is important parameter of the refractory features of the coating and the sand core and mould.

References

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Issue

Journal of the Balkan Tribological Association, vol. 31, pp. 504-513, 2025, Albania, ISSN 13104772

Вид: статия в списание, публикация в реферирано издание, индексирана в Scopus