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Journal of Materials Science

, Volume 23, Issue 9, pp 3254–3257 | Cite as

The kinetics of cubic boron nitride formation in the system BN-Mg2N2

  • Helmar Lorenz
  • Bernd Lorenz
  • Ulrich Kühne
  • Christian Hohlfeld
Article

Abstract

Cubic boron nitride is synthesized using Mg3N2 as a catalyst at a pressure of 6.5 GPa in the temperature range 1600<T<2200 K. The temperature variations of growth and net transformation rates are estimated. Above 1650 K the transformation kinetics is well described by a nucleation and growth process. The theoretical description based on the homogeneous nucleation and layer growth mechanism yields reasonable results in comparison with the experimental data. The relevant parameters are estimated and discussed. The effect of the catalyst is suggested to consist in lowering the activation enthalpy for nucleation. Below 1650 K it is shown that the transformation kinetics changes qualitatively and the nucleation and growth mechanism is not the appropriate description. The physics of transformation in this temperature range have hitherto remained unexplained.

Keywords

Polymer Enthalpy Boron Temperature Variation Nitride 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman and Hall Ltd 1988

Authors and Affiliations

  • Helmar Lorenz
    • 1
  • Bernd Lorenz
    • 1
  • Ulrich Kühne
    • 1
  • Christian Hohlfeld
    • 1
  1. 1.Central Institute for Physics of the EarthAcademy of Sciences of the GDRPotsdamGDR

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