Effects of the addition of $TiO_2$, $Cr_2O_3$ on sintering behavior and slag resistance of $ZrSiO_4$ bodies were investigated.
The mixtures of $ZrSiO_4$ and additives were sintered at 1550℃ and 1600℃ for 3hrs in air. Shrinkage, bulk density, apparent density, apparent porosity and bending strength of sintered bodies were measured in relation with sintering temperature and content of additives. Slag resistance of sintered bodies were compared by button test. Scanning electron microscopy and X-ray diffraction were used for microstructural analysis.
Sintering of $ZrSiO_4$ was promoted by the addition of $TiO_2$·$Cr_2O_3$. The promotion of $ZrSiO_4$ was due to liquid phase, $ZrTiO_4$ and $Cr_2Ti_2O_7$. Bending strength of $ZrSiO_4$ bodies sintered with $TiO_2$ was higher than with $TiO_2$·$Cr_2O_3$. The sharp increase of bending strength at the composition of 1% per both $TiO_2·Cr_2O_3$ and $Cr_2O_3$ was considered to be result of solid solution of $Cr_2O_3$ at the dissociated $ZrO_2$. Slag resistance of $ZrSiO_4$ was improved by the addition of $TiO_2$·$Cr_2O_3$, but $TiO_2$ increased slag penetration due to liquid phase in large quantities came from $ZrSiO_4$ dissociation.
