ZIRCONIA COMPOUNDED ALUMINA CERAMIC SINTERED BODY, PREPARATION METHOD THEREFOR AND USE THEREOF

The present invention discloses a zirconia-alumina composite ceramic sintered body, comprising the following components in percentage by mass: 0.01% - 20% of a zirconium-containing compound (content thereof calculated with zirconia), 0 - 1.75% of a yttrium-containing compound (content thereof calculated with yttrium oxide), 0.01% - 0.8% of a silicon-containing compound (content thereof calculated with silicon oxide), 0 - 0.035% of a calcium-containing compound (content thereof calculated with calcium oxide), 0 - 0.05% of a magnesium-containing compound (content thereof calculated with magnesium oxide), and the balance being alumina. In the present invention, by reducing flux content, the impacts of the flux on grain boundary strength and phonon transmission rate can be reduced. The initial particle size and uniformity of dispersion of ZrO2 is controlled, thereby allowing the densification of the Al2O3 matrix fluxed by ZrO2, increasing the mechanical strength and thermal conductivity of the alumina ceramic matrix. The invention also discloses an alumina substrate comprising the aforementioned sintered body, and a preparation method thereof.