Abstract
We have used chemical analysis, x-ray diffractometry, transmission and scanning electron microscopy, and also measurement of the specific surface area to study the characteristic patterns of nitriding and structure formation in graphite-like BN powders synthesized by the carbamide method under various conditions. We have studied the effect on the synthesis process from the ratio of boric acid to carbamide in the starting mixture, preliminary grinding of the charge, the nitriding temperature and time. We show that the major factor determining the composition and structure of the product synthesized at 900–1200 °C is the ratio of the starting components. Carbon-free BN of stoichiometric composition is formed for a 1: 3 ratio of boric acid to carbamide as a result of two-hour nitriding at 1200 °C. The graphite-like BN obtained is characterized by a turbostratic nanocrystalline structure with a specific surface area of 100 m2/g and high nanoporosity of the powder particles.
Similar content being viewed by others
References
A. V. Kurdyumov, V. F. Britun, N. I. Borimchuk, et al., “Phase transformations in disordered structures of graphite-like boron nitride during high-temperature shock compression,” Poroshk. Metall., Nos. 11–12, 95–102 (2003).
T. S. Bartnitskaya, A. V. Kurdyumov, V. I. Lyashenko, and N. F. Ostrovskaya, “Physicochemical characteristics of catalytic synthesis of boron nitride,” Sverkhtverdye Materialy, No. 6, 27–33 (1996).
V. P. Sadkovskii, E. N. Yurchenko, I. G. Kuznetsova, et al., “Effect of synthesis conditions for turbostratic boron nitride on some of its properties,” in: Papers of the D. I. Mendeleev Moscow Chemical Engineering Institute. Silicates [in Russian], Moscow (1971), pp. 130–132.
D. N. Poluboyarinov, E. I. Sadkovskii, and I. G. Kuznetsova, “Study of the process of turbostratic boron nitride synthesis,” in: Papers of the D. I. Mendeleev Moscow Chemical Engineering Institute. Silicates [in Russian], Moscow (1973), pp. 79–81.
T. S. Batnitskaya and A. F. Alekseev, “Study of the process of obtaining boron nitride from boric acid and carbamide,” in: Nitride Research [in Russian], Nauk. Dumka, Kiev (1975), pp. 67–69.
V. V. Vikulin, A. N. Rusanova, V. F. Kuznetsova, et al., “Study of the dependence of the oxygen content on heat treatment and its effect on the structure and strength characteristics of boron nitride,” Poroshk. Metall., No. 9, 64–68 (1978).
M. Hubacek and M. Ueki, “Chemical reactions in hexagonal boron nitride system,” J. Solid State Chem., 123, 215–222 (1996).
Z. Gontarz and S. Podsiadlo, “Stages of reaction between boron oxy compounds and compounds of urea group. Part I,” Polish J. Chemistry, 58, No. 1–3, 3–11 (1984).
Z. Gontarz and S. Podsiadlo, “Stages of reaction between boron oxy compounds and compounds of urea group. Part II,” Polish J. Chemistry, 58, No. 1–3, 13–21 (1984).
Yu. I. Krasnokutskii, E. D. Tarasova, and V. I. Fedorov, “Mechanism of the process for obtaining boron nitride by the carbamide method,” Latvijas Kimijas Zurnals, No. 6, 719–723 (1992).
A. V. Kurdyumov, “Stacking faults in graphite-like boron nitride,” Kristallografiya, 20, No. 5, 969–973 (1975).
A. V. Kurdyumov, V. B. Zelyavskii, and S. N. Gromyko, “Precision measurement of lattice parameters in polymorphic modifications of boron nitride,” Poroshk. Metall., Nos. 5–6, 100–108 (1998).
A. V. Kurdyumov, V. B. Zelyavskii, N. F. Ostrovskaya, et al., “Characteristic features of the real structure of graphite-like BN and its transformations to the wurtzite modification under shock compression,” Poroshk. Metall., Nos. 9–10, 62–66 (1994).
J. Thomas, N. E. Weston, and T. E. O’Connor, “Turbostratic boron nitride thermal transformation to ordered layer-lattice boron nitride,” J. Amer. Chem. Soc., 84, 4619–4622 (1962).
Author information
Authors and Affiliations
Additional information
__________
Translated from Poroshkovaya Metallurgiya, Nos. 11–12(446), pp. 88–97, November–December, 2005.
Rights and permissions
About this article
Cite this article
Kurdyumov, A.V., Bartnitskaya, T.S., Lyashenko, V.I. et al. Structure formation patterns in carbamide synthesis of nanocrystalline graphite-like boron nitride. Powder Metall Met Ceram 44, 590–597 (2005). https://doi.org/10.1007/s11106-006-0030-0
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11106-006-0030-0