In-situ hot pressing sintering behaviors of Y2O3-La2O3 co-doped AlON ceramic

Abstract Aluminum oxynitride (AlON) ceramic was fabricated by in-situ hot pressing sintering (HPS) from Al 2 O 3 and AlN doped with Y 2 O 3 and La 2 O 3 as well as without dopant for comparison. Dense AlON ceramic with a relative density of 99.7% was obtained by HPS doped with 0.4 wt% Y 2 O 3 and 0.1 wt% La 2 O 3 at 1700 °C for 4 h. The maximum fracture toughness of AlON ceramic with and without dopant was 3.74 MPa m 1/2 and 2.27 MPa m 1/2 , respectively. The maximum Vickers hardness of AlON ceramic with and without dopant was 18.3 GPa and 16.5 GPa, respectively. Compared with those of undoped AlON ceramic, the relative density and the fracture toughness of Y 2 O 3 -La 2 O 3 co-doped AlON ceramic were obviously improved. Overlarge grain size would reduce the Vickers hardness of AlON. The sintering activation energy of Y 2 O 3 -La 2 O 3 co-doped AlON was about 57% of that of undoped AlON. The sintering activity of AlON was highly improved by co-doping with Y 2 O 3 and La 2 O 3 .