Zirconium compounds are of great interest for ceramic application due to their excellent thermal and mechanical properties. Zirconium phases of the system Zr-O-C-N were obtained using carbonitriding reactions of zircon mineral (ZrO2.SiO2), under different reaction conditions. The reaction products were studied by X-ray diffraction (XRD) using the Rietveld method. Silicon was employed as internal standard. Zirconium compounds formed were m-ZrO2 (monoclinic), beta"-zirconium oxynitride and a cubic Zr(C,N,O) phase whose lattice parameter a o depends on the composition. The crystallite sizes of the three zirconium phases were determined also by XRD. The minority phases present are the ones of the Si-O-N-C system. The reaction conditions employed allows to obtain reaction products with low or without silicon content.
ZrC; ZrN; beta"-phases; Rietveld
