Abstract

Ultrafine gamma-Fe(C), alpha-Fe(C) and Fe3C particles were prepared by arc-discharge synthesis in a methane atmosphere. The phases, morphology, structure and surface layer of the particles were studied by means of X-ray diffraction (XRD), transmission electron microscopy (TEM) techniques and X-ray photoelectron spectroscopy (XPS). It was found that the mean particle size ranged from 9.8 to 12.8 nm. The surface of particles mostly consisted of a carbon layer and a little oxide. Phase transformation from gamma-Fe(C) to alpha-Fe(C) was studied by annealing in vacuum and by differential thermal analysis and thermogravimetry (DTA-TGA) measurement. The abundance of gamma-Fe( C) was determined by a magnetization measurement to be approximately 30%. Phase transformation occurred between 300 and 500 degrees C in a flowing argon atmosphere. The Fe3C particles oxidized to alpha-Fe2O3 and carbon dioxide at 610 degrees C or so. (C) 1998 Chapman & Hall.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.