Synthesis of Zr-Si-O-N phases by carbonitriding reaction. Characterization of crystalline phases using the Rietveld method

Abstract

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), β"-zirconium oxynitride and a cubic Zr(C,N,O) phase whose lattice parameter ao 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.

High-pressure chemistry of nitride-based materials

“…Many transition metal oxynitrides, especially compounds of the 4d and 5d metals such as Ta, Hf and Zr, are now known to have electronic and mechanical properties that can be intermediate to those of their oxide and nitride components, or can have quite different behavior to the end-members. 273 The introduction of oxygen into nitrides, such as Ta 3 N 5 , that are developed as pigments can permit adjustment of their colour. 274 A wide variety of complex alkali-or alkaline-earth and Si-bearing oxynitride compounds with transition metals and lanthanides have now been synthesized.…”

Synthesis of Group IVB Metals Oxicarbides by Carboreduction Reactions

“…The R exp are between 4.63 and 5.97 and the R wp are between 9.20 and 15.56. This phenomenon can be observed in other systems where there are phases having changeable compositions and unit-cell parameters associated [13][14][15] .…”