Synthesis of an alumina–YAG nanopowder via sol–gel method

Alumina–YAG (Y3Al5O12) composite has attracted a great deal of attention as a high temperature structural ceramic due to its good creep resistance. In the present article, an Al2O3–YAG nanopowder was synthesized by aqueous sol–gel method using AlCl3·6H2O, aluminum and Y2O3 powders as raw materials. The dried amorphous gel was heat treated in the range of 600–1500 °C. The influence of heat treatment on crystallization and phase transformation of the dried gel was investigated using X-ray diffractometery (XRD), scanning electron microscopy (SEM), thermogravimetry and differential thermal analysis (TG–DTA) and Fourier transform infrared spectroscopy (FTIR). It was shown that the gel heat treated at 1300 °C resulted in the formation of a crystalline Al2O3–YAG nanopowder with particle size distribution ranges from 70 to 130 nm.