| Autor: |
Gadakary, Saikumar, Khanra, Asit Kumar |
| Předmět: |
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| Zdroj: |
Annual International Conference on Materials Science, Metal & Manufacturing; 2016, p11-20, 10p |
| Abstrakt: |
Borides (TiB2/ZrB2) are emerging as potential material for the ultra-high temperature applications. Present investigation attempts to study the morphology of various borides powder through electron microscope. The borides powder are produced by two different techniques such as carbothermal and self-propagating high temperature synthesis (SHS) respectively. In the carbothermal process, the boride powders are produced by pyrolysis of mixture containing respective oxide precursor, H3BO3, carbon with different catalysts whereas in SHS process, a stoichiometric mixture of respective oxides, H3BO3, and Mg powder is synthesized in a resistance heating tubular furnace with continuous flow of pure Argon gas. The synthesis is also carried out with NaCl as a diluent. The MgO is leached out from the as-synthesized powder. The scanning electron microscope (SEM) images of boride powder produced by carbothermal process shows formation of spherical particles and whiskers. The whiskers morphology is found to vary with the process parameters. The transmission electron microscope (TEM) images of SHS powder shows formation of nanocrystalline borides powder. The morphology of powder is found to change with the diluent addition and reaction step. TEM images of SHS powder shows presence of crystallographic defects. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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