Synthesis of Chromite for Subsequent Carburization by Methane-Hydrogen Gas Mixture

Abstract

The syntheses of stoichiometric iron chromite and chromites with chosen impurity content have been developed using the induction skull melting technique. The aim for this synthetic material is to obtain pure samples to study the carburization by methane-hydrogen gas mixtures. For each synthesis, the parameters influencing the skull melting experiment have been considered. The product phases have been analyzed using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS) and X-ray Photoelectron Spectroscopy (XPS). The synthetic material was subsequently pelletized and sintered in argon. The use of excess iron was found to improve the quality of the final product as well as to help the melting. The difference in magnesium content between first and last solids formed seem to indicate a segregation phenomenon, while no evidence could support a similar trend for aluminum substitution in chromite.