Catalytic effect of alkaline earth oxides on carbothermic formation of hexagonal boron nitride

Date

2009-08-01

Author

ÇAMURLU, HASAN ERDEM
Topkaya, Yavuz Ali
SEVİNÇ, NACİ

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Effect of MgO, CaO and BaO on carbothermic formation of hexagonal boron nitride (h-BN) was investigated. B(2)O(3-)C mixtures containing alkaline earth oxide additives were reacted at 1500 degrees C for 30-120 min in nitrogen atmosphere. Formed phases in the reaction products were determined by powder-XRD analyses, and amounts of the constituents were determined by chemical analyses. Particle size and morphology of the formed h-BN powders were examined by FESEM and particle size distributions were determined by particle size analyzer. Addition of alkaline earth oxides was found to increase the amount and grain size of h-BN significantly and to decrease the amount of B(4)C formed in the system. Investigated alkaline earth oxides presented similar catalytic effects according to chemical analyses and FESEM observations. While the average particle size of h-BN powder obtained from plain mixture was 149 nm, those obtained from MgO, CaO and BaO containing mixtures were 297, 367 and 429 run, respectively. (C) 2009 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Subject Keywords

Process Chemistry and Technology, Materials Chemistry, Electronic, Optical and Magnetic Materials, Surfaces, Coatings and Films, Ceramics and Composites

URI

https://hdl.handle.net/11511/43720

Journal

CERAMICS INTERNATIONAL

DOI

https://doi.org/10.1016/j.ceramint.2008.12.005

Collections

Department of Metallurgical and Materials Engineering, Article

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Citation Formats

H. E. ÇAMURLU, Y. A. Topkaya, and N. SEVİNÇ, “Catalytic effect of alkaline earth oxides on carbothermic formation of hexagonal boron nitride,” CERAMICS INTERNATIONAL, pp. 2271–2275, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43720.