Effects of adding Y(NO3)(3)center dot 6H(2)O on the phase change behavior and thermal conductivity of Aluminum Nitride ceramics

The phase change behavior and thermal conductivity of Aluminum nitride (AlN) ceramics with Y(NO3)(3)center dot 6H(2)O and Y2O3 as an additive were studied. Sintering was performed in the temperature of 1,900 degrees C for up to 3 h under a N-2 atmosphere to optimize the sintering conditions for each composition. The microstructure and assemblage of the secondary phase have a significant effect on the final thermal conductivity of the sintered AlN. The mechanical property and thermal conductivity of the AlN composition of using the Y2O3 additive were improved by adding Y(NO3)(3)center dot 6H(2)O, which decreased the porosity. At 13.56 wt% Y(NO3)(3)center dot 6H(2)O, the AlN ceramic exhibited the highest strength of 375 MPa, the highest hardness of 10.60 GPa, and the highest thermal conductivity of 200.2 W/m.K.