Coating of Y2O3 additive on AlN powder and its effect on the thermal conductivity of AlN ceramics

Abstract

AlN powder was coated with Y2O3 percursor generated by in situ precipitation of Y(NO3)3 · 6H2O in isopropanol solution. In order to avoid the hydration of AlN powder the isopropanol saturated with ammonia gas was used as a precipitating agent. TEM observation and elemental analysis clearly showed that the Y2O3 precursor was successfully coated over the surfaces of the AlN particles while minimizing the hydration of AlN powder. The precipitation behavior of the Y2O3 precursor was characterized by XRD, FTIR, and TG/DTA. Densification behavior and thermal conductivity of the specimens prepared from the coated powders were investigated. Due to the homogeneous distribution of Y2O3, the specimen made from the coated powders showed faster densification rate and higher thermal conductivity compared with the specimen made from the conventionally mixed one.

2-s2.0-0029215919 3

AlN powder was coated with Y2O3 percursor generated by in situ precipitation of Y(NO3)3 · 6H2O in isopropanol solution. In order to avoid the hydration of AlN powder the isopropanol saturated with ammonia gas was used as a precipitating agent. TEM observation and elemental analysis clearly showed that the Y2O3 precursor was successfully coated over the surfaces of the AlN particles while minimizing the hydration of AlN powder. The precipitation behavior of the Y2O3 precursor was characterized by XRD, FTIR, and TG/DTA. Densification behavior and thermal conductivity of the specimens prepared from the coated powders were investigated. Due to the homogeneous distribution of Y2O3, the specimen made from the coated powders showed faster densification rate and higher thermal conductivity compared with the specimen made from the conventionally mixed one.

2-s2.0-0029215919 3