Rapid and cost-effective method for synthesizing zirconium silicides

Abstract

An experimental study on the preparation of zirconium silicides was conducted using ZrSiO4-Mg, ZrSiO4-SiO2-Mg and ZrSiO4-ZrO2-Mg powder mixtures by the combustion synthesis (CS) technique. Test specimens having different composition ratios including Zr:Si = 1:2, 1:1, 5:4, 5:3, 2:1, and 3:1 were employed in this study. Temperature profiles relative to all the starting compositions were measured using thermocouples, and the values of the combustion parameters (combustion temperature and wave velocity) were estimated using the same. The formation of ZrSi, ZrSi2, Zr5Si3, and Zr3Si2 phases was confirmed by X-ray analysis: however, only ZrSi was produced as a single-phase product. The proposed method was also extended to synthesize spherical ZrSi particles having mean diameters of 0.2-3.0 mu m. A comprehensive chemical pathway to describe the sequence of chemical reactions in the combustion wave was also proposed.