Physical and physicochemical processes accompanying powder synthesis, growth of PbMoO4 crystals, and their annealing in various media: II. Shape of the crystal-melt interface caused by melt evaporation and supercooling
| Autor: | O. S. Grunskii, V. T. Gabrielyan, A. V. Denisov |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Convection
Natural convection Materials science Annealing (metallurgy) Thermodynamics General Chemistry Condensed Matter Physics law.invention Condensed Matter::Soft Condensed Matter Crystal Thermocouple law Condensed Matter::Superconductivity Thermal General Materials Science Crystallization Supercooling |
| Zdroj: | Crystallography Reports. 50:486-489 |
| ISSN: | 1562-689X 1063-7745 |
| DOI: | 10.1134/1.1927614 |
| Popis: | The temperature distribution in a melt of PbMoO4 is investigated using a modified thermocouple and a scanning device. It is shown that the PbMoO4 melt whose thermal field is significantly inhomogeneous at different depths demonstrates a strong (below the melting temperature) supercooling at the surface due to the evaporation. The position of the isotherm corresponding to the melting temperature of PbMoO4 in the melt is determined by the degree of the melt supercooling at different growth parameters. The results obtained show that the conditions of mass and heat exchange in the melt are mainly determined by convection. The free convection remains dominant even at intense rotation of a crystal and the most thorough thermal isolation of the crystallization unit. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|