Effects of High Temperature Vaporization of Impurities from Refractory on the Coloration of Zirconia Surface

Abstract

Coloration is an important effect in zirconia ceramics. We have observed a phenomena of coloration on the surface of 3mo1%Y₂O₃-doped zirconia in sintered processing used some of new refractory. XPS, TG and IR analyses have proved that the problem is caused by the influence of residual impurities in the refractory.
The authors however have found a interested results that the phenomena was improved by reheating the refractory in the high temperature for several times before using, and the doping of Y₂0₃ or A1₂0₃ content into ZrO₂ ceramics(PSZ) has improved the coloration.