Formation and crystallographic relations of iron phases and iron carbides inside the carbon nanotubes
Vladimir D. Blank, Yulia S. Buranova, Boris A. Kulnitskiy, Igor A. Perezhogin, Rustem H. Bagramov and Gennady A. Dubitsky
The present study provides a transmission electron microscopy investigation of iron/iron carbide phase transformations inside the multiwalled carbon nanotubes synthesized in a high isostatic pressure apparatus. Carbon nanotubes contained mostly Fe3C nanoparticles often with inclusions of one of the following: α-, γ- or ε-iron. This evidences the ability of a nanotube to preserve the high-pressure (ε-iron) and high-temperature (γ-iron) phases. We established the orientation relationships between iron phases, appeared to be in accordance with the ones theoretically predicted earlier.
Keywords: Hot isostatic pressing (HIP); transmission electron microscopy (TEM); carbon nanotubes; metastable phases; orientation relationships in iron; iron carbides.