Zirconium diboride (ZrB2) has some excellent physical properties and chemical stability, it has been widely applied in many fields, but the sintering densification of ZrB2 is very difficult, and it is easily oxidized at high temperature. In order to improve the disadvantages of ZrB2, Al2O3-Y2O3/ZrB2 composite powders were prepared by a co-precipitation methods. When the pH is 9, the encapsulted structure of A1(OH)3-Y(OH)3/ZrB2 composite powders is best. Through analyzing ZrB2 surface status with SEM, EDS, TEM and XRD, the A12O3-Y2O3/ZrB2 composite powders were prepared by calcining at 600 oC in argon. The density of ZrB2-YAG ceramics with Al2O3-Y2O3 composite powders added is higer than that of ZrB2-YAG ceramics, which indicates the A12O3-Y2O3/ZrB2 composite powders are more easily prepared than high density ZrB2-YAG ceramics.

Keywords: ZrB2, YAG, Composite powders, co-precipitation methods, Sintering behavior