2016-Sustainable Industrial Processing Summit
SIPS 2016 Volume 9: Molten Salts and Ionic Liquids, Energy Production
| Editors: | Kongoli F, Gaune-Escard M, Turna T, Mauntz M, Dodds H.L. |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2016 |
| Pages: | 390 pages |
| ISBN: | 978-1-987820-24-9 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Heat-Resistant CrSi2: Synthesis of Nanocrystalline Powders, Single Crystals, and Coatings from Molten Salts
Liliia Molotovska1; Dmytro Shakhnin1; Viktor Malyshev2; Alla Sushchenko1; Marcelle Gaune-Escard3;1V.I. VERNADSKY INSTITUTE OF GENERAL AND INORGANIC CHEMISTRY OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE, Kyiv, Ukraine; 2IGIC NASU, Kyiv, Ukraine; 3AIX-MARSEILLE UNIVERSITé/POLYTECH, CNRS/IUSTI UMR7343, Marseille, France;
Type of Paper: Regular
Id Paper: 205
Topic: 13
Abstract:
The purpose of this work was the synthesis of heat resistant chromium disilicide nanocrystalline powders, single crystals, and coatings.<br />CrSi2 as the nanocrystalline powder was synthesized by co-reducing of anhydrous CrCl3 and Na2SiF6 with Na.<br />Single crystals were obtained by solution growth method with molten Sn-Zn (in weight ratio 1:10) as a flux. Cr and Si powder 99.9% purity in an atomic ratio 1:2 were added to Sn-Zn melt in weight ratio 1:10.<br />CrSi2 coatings were obtained by currentless deposition of Si onto pure chromium substrate in the molten KCl-NaCl-NaF-Na2SiF6-Si system.<br />TGA and DSC results show that the highest oxidation resistance in the air has nanocrystalline CrSi2 powders (800 ºC). Single crystals and coatings were resistant up to 700 ºC. A slight increase of samples weight (from 4,6% to 6,8%) was found. Subsequently, the protective oxide layer of SiO2 was formed on samples surface. Obtained values of temperature resistance for nanocrystalline powders, single crystals, and coatings were different. It can be related to size and morphology of synthesized samples, and also with the method of product obtaining. Due to high oxidation resistance, obtained samples could be used as heat resistant details and coating for devices working at elevated temperatures.<br />Keywords: chromium disilicide, X-ray diffraction, differential thermogravimetric analysis, oxidation resistance.
Keywords:
Molten Salt Chemistry and Thermodynamics;References:
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