Low-temperature calcination at 800 °C of alumina–zirconia nanocomposites using sugar as a gelling agent

Alumina–zirconia nanocomposite powder was synthesized at a room temperature and calcined at a lower temperature than 1000 °C of about 800 °C by sugar precursor process. In the synthesis process of the nanocomposite powder, sugar was used as a gelling agent. The synthesized powder was calcined at temperatures of 800 °C, 900 °C, 1000 °C, 1100 °C, and 1200 °C for 5 h. The calcined powder was characterized by X-ray diffraction (XRD), a SYMPATEC NIMBUS particle size analysis, and transmission electron microscopy (TEM). Alumina–zirconia nanocomposites were obtained at 800 °C, where the phases formed were γ-Al2O3, m-ZrO2, and t-ZrO2. The TEM results showed that the average grain sizes of the nanocomposite were less than 25 nm in diameter. At 800 °C, a particle size analyzer measured the largest nanocomposite particles as having a size of about 40 nm, accounting for 3.49% of the total, while the most commonly sized partical was about 10 nm for 39.87%. A further phase transformation of alumina–zirconia nanocomposites was obtained at 1100 °C, where the phases formed were α-Al2O3, m-ZrO2, and t-ZrO2; the TEM results show that the average grain sizes of the nanocomposite powder were below 50 nm in diameter.