caa a22 4500 46578125X CHVBK 20180323111956.0 cr unu---uuuuu 170327e19900901xx s 000 0 eng 10.1007/BF01282780 doi (NATIONALLICENCE)springer-10.1007/BF01282780 Influence of technological factors on obtaining ingots of mullite and mullite-corundum compositions [Elektronische Daten] [V. Ustichenko, N. Pitak, V. Shapovalov] Conclusions: It is shown that, depending on the composition of the original body, with the same cooling conditions for the melt, crystallization of mullite develops in three different types distinguished by structure, chemical, and phase composition. In the OKB-514 arc furnace, using a voltage of 194 V and a current of 1800 A it is possible to synthesize mullite, whose composition is slightly different from that of the orginal mixture. The use of lower voltages causes slight changes in the compositon of the fused materials on account of the reduction of part of the SiO2 and the resulting materials of mullite-corundum composition. It is found that the loss of SiO2 during fusing occurs mainly in the initial period of melting of silica-containing constituent of the mixture. Coarsening the grain-size composition of this component leads to an increased loss of silica and corundum enrichment of the melt. The ingots of molten material contain crystallization structures that vary in relation to the alumina modulus. When Al2O3/SiO2<3.5 crystallization of mullite has a directional character, moving from the cooling surface to the center of the ingot. When Al2O3/SiO2 is from 3.5 to 4.5 the ingot develops a zonal structure; in the lower part corundum crystallizes with mullite; in the upper zone we note directional crystallization of mullite. When A12O3/ SiO2>4.5 the ingot forms fine-grained structures from grains of corundum of prismatic and isometric form and also mullite. Plenum Publishing Corporation, 1991 Ustichenko V. Ukrainian Research Institute of Refractories, Ukraine aut Pitak N. Ukrainian Research Institute of Refractories, Ukraine aut Shapovalov V. Ukrainian Research Institute of Refractories, Ukraine aut Refractories Kluwer Academic Publishers-Plenum Publishers 31/9-10(1990-09-01), 502-510 0034-3102 31:9-10<502 1990 31 11148 https://doi.org/10.1007/BF01282780 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01282780 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ustichenko V. Ukrainian Research Institute of Refractories, Ukraine aut NATIONALLICENCE 700 1- Pitak N. Ukrainian Research Institute of Refractories, Ukraine aut NATIONALLICENCE 700 1- Shapovalov V. Ukrainian Research Institute of Refractories, Ukraine aut NATIONALLICENCE 773 0- Refractories Kluwer Academic Publishers-Plenum Publishers 31/9-10(1990-09-01), 502-510 0034-3102 31:9-10<502 1990 31 11148 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer