PSI - Issue 41

533 7

A.M. Ignatova et al. / Procedia Structural Integrity 41 (2022) 527–534 Ignatova A.M., Verescha in V.I., Naimark O.B./ Structural Integrity Procedia 00 ( 019) 000–000

Fig. 5. Cluster of spinels around a pore in the course of the crystallization process.

Conclusions. The study of peculiarities of formation of the structure of cast glass-ceramic spinel-pyroxene materials under non-equilibrium conditions has established that: 1) the morphological parameters of structural components, in particular, spinels, under non-equilibrium crystallization are influenced not only by the cooling rate but also by the conditions of solidification (contact with air, with mold, no contact); the milder is the mode of crystallization, that is the lower is the cooling rate, the higher is the density of spinel distribution and the size of the largest components; 2) when crystallizing the casts in the mold, five typical zones are distinguished: a zone of direct air contact; a transition zone between air cooling and cast center; a zone without contact with the external environment; a transition zone between the cast center and the zone of contact with the mold's wall; a zone of direct contact with the mold; 3) the length of some of the zones depends on the mode of crystallization: the less equilibrium it has, the shorter is the no-contact zone, and the longer is the zones of contact with air and mold; 4) there is a mechanism that causes microzoning of the structure: during crystallization, a specific critical size of spinel is achieved when the spinel acquires its own “zone of influence”; that is, a particular area of the melt proportional to the size of the spinel becomes material for the formation of a shell around the spinel by way of epitaxial growth. Funding. This research was supported by the Russian Science Foundation (grant no. 21-79-30041) References Ignatova A.M., Vereshchagin V.I. Model of stone casting material structure with increased wear resistance // Materialovedenie (Material Science) 2017. No. 5. pp. 13-17. Ignatova A.M., Vereshchagin V.I. Use of image analysis method in the study and statistical evaluation of particle parameters of the solid component of silicate and oxide-based welding aerosols // Bulletin of Perm National Research Polytechnic University. Mechanical Engineering, Material Science. 2017. Vol. 19. No. 1. pp. 41-57. Ignatova A.M., Vereshchagin V.V. Prediction of properties of cast spinelide-pyroxene glass-ceramic materials through parameters of spherolite mesh structure model // Materialovedenie (Material Science). 2020. No. 2. pp. 32-37. Ivanov O.K. The order of crystallization of minerals in equilibrium and non-equilibrium orthomagmatic rocks // Ural Geological Journal. 2008. No. 2 (62). pp. 17-35. Popov V.A. Practical crystallomorphology of minerals. Sverdlovsk. USC AS USSR. 1984. 190 p. Ivanov O.K. Factors determining the number of co-crystallizing minerals of equilibrium orthomagmatic rocks // Ural Geological Journal. 2006. No. 4(52). P. 23-44. Fedorov P.P. Tamman's paradox and amorphization of substances under pressure// P.P. Fedorov // Crystallography. 2008. Vol. 53, No. 1. - pp. 117 121. Volarovich M.P., Korchemkin L.I. Relation between viscosity of melted rocks and acidity according to Levinson-Lessing F.Yu. – AS USSR Proceedings. 1937. Vol. 17. No. 8. P. 413-418.