Premium
Desilicating Zircon with Plasma Heating and Phase Equilibrium Analyses
Author(s) -
Yuan Zhangfu,
Pan Yifang,
Luo Min,
Liu Jishen
Publication year - 2003
Publication title -
steel research international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.603
H-Index - 49
eISSN - 1869-344X
pISSN - 1611-3683
DOI - 10.1002/srin.200300230
Subject(s) - cubic zirconia , materials science , plasma , zircon , mass fraction , phase (matter) , zirconium , metallurgy , analytical chemistry (journal) , chemistry , environmental chemistry , ceramic , geology , geochemistry , composite material , organic chemistry , physics , quantum mechanics
Desilicated zirconia has a great variety of applications. The maximum SiO 2 content in desilicated zirconia is <7 mass%. The present techniques to produce zirconia are always accompanied by many drawbacks. So the authors have developed a new plasma process. Desilicated zirconia (88.6 ~ 96.9 mass% ZrO 2 ) and magnesia‐stabilized zirconia (> 91.54 mass% ZrO 2 , < 5.39 mass% MgO) were produced successfully from zircon using a 150 kW plasma rotating furnace. The effects of time and carbon content on the desilication degree were investigated. The mixture treated in the plasma furnace included condensed phases Zr, ZrC, ZrN, ZrO 2 , C, Si, SiC, SiO 2 and gaseous phases SiO, O 2 , N 2 , CO. The established phase equilibrium diagrams of the Si‐C‐N‐O and Zr‐C‐N‐O systems suggest that the formation of Si 3 N 4 is thermodynamically impossible, and the formation of ZrC and ZrN is thermodynamically possible in the central high‐temperature region of the plasma furnace. Experimental results supported the analyses.