Synthesis of Group IVB Metals Oxicarbides by Carboreduction Reactions

Abstract

The metals of the group IV B (Ti, Zr, Hf) present a series of carbides and oxicarbides with scientific and technological interest. Many of these compounds belong to the subsystem “MO - MC” of the pseudoternary “MO - MN - MC” system (where M = Ti, Zr or Hf). In this work carboreduction reactions of TiO2 and ZrO2 were performed in argon atmosphere, using temperatures from 1250° to 1650° and reaction times of 120 min. The oxicarbides obtained were in the range TiC0.16 O0.84 to TiC0.73 O0.27 and ZrC0.46 O0.54 to ZrC0.90 O0.10 respectively. The reaction products were characterized by X-ray diffraction (XRD), with the calculation of their cell constants by means of the Rietveld method. Scanning Electron Microscopy (SEM) was used in the characterization of powdered materials. Additionally, the carborreduction reaction was followed by weight loss.