| Autor: |
Yu. A. Dmitrienko, F. S. Kaplan, V. N. Koptelov, M. Yu. Koreshkova, I. G. Maryasev |
| Rok vydání: |
2003 |
| Předmět: |
|
| Zdroj: |
Refractories and Industrial Ceramics. 44:405-410 |
| ISSN: |
1083-4877 |
| DOI: |
10.1023/b:refr.0000016779.02545.4c |
| Popis: |
Results for alumomagnesian spinel prepared by fusing periclase from natural magnesite and alumina at 30.5 – 32.5% MgO are reported. The structure of solidified melt is similar to that of eutectic; the role of impurities and nonequilibrium crystallization conditions is discussed. Spinel crystals with a composition close to stoichiometric and iron-in-periclase solid solutions are shown to form. Impurities in the form of a low-melting glass containing up to 20% of alkalis and merwinite are shown to concentrate in the interstitial space of the two phases. The structure thus produced cannot be considered as optimum because the liquid phase that forms in the crystalline phase at relatively low heating temperatures will adversely affect the high-temperature strength and corrosive resistance of the material. For this reason, development of methods that would allow preparation of a high-quality fused spinel from inexpensive raw materials and allow control over the distribution of impurities in spinel solid solutions remains a challenging problem. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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