Influence of Transferred Arc Plasma Melting Time on the Formation of Phase and Microstructure of Mullite-Zirconia Composite

Abstract

Transferred arc plasma is an effective and simple technique to synthesis a high temperature reaction ceramic composite material. In this paper, 20 kW transferred arc plasma torch was used to synthesis mullite-zirconia composites through the solid-state reaction of 3:2 mole ratio of ball milled alumina and zircon powders. Dissociation of zircon in a thermal plasma arc is utilized as to prepare mullite-zirconia composites. The ball milled samples are melted for 3, 6, 9 and 12 minutes in transferred arc plasma torch at 20 kW power level with 10 lpm of argon flow rate and cooled by air. The phase and microstructure of melted samples were determined from X-ray diffraction (XRD) and SEM images. The obtained results shows that the processing time significantly influence on the formation of phase and microstructure of the mullite- zirconia composite.