Synthesis and electric field-assisted sintering behavior of Al2O3–ZrO2 composite nanopowders by polyacrylamide gel method

Abstract Al 2 O 3 –ZrO 2 composite ceramic nanopowders were synthesized using a polyacrylamide gel method. The mean particle size of the Al 2 O 3 –ZrO 2 nanopowders was found to decrease with increasing mole ratio of monomer to the precursor salt. The Al 2 O 3 –ZrO 2 nanopowders with mean particle size of 10 nm can be densified in 1 h at 965 °C, by application of a dc electrical field. Under a constant dc electrical field, the current density through the sample of Al 2 O 3 –ZrO 2 rose rapidly when the temperature increased to a certain value. In the sintering process, the current density was restricted when a sharp increase occurred. It was found that current density had a great effect on the sintering process in electric field-assisted sintering. Joule heating was proposed to be the main mechanism of the electric field-assisted sintering process. Graphical Abstract The Al 2 O 3 –ZrO 2 composite ceramic nanopowders were synthesized using a polyacrylamide gel method. The Al 2 O 3 –ZrO 2 nanopowders can be densified in 1 h at low temperature, by the application of a dc electrical field. Under a constant dc electrical field, the current density through the sample of Al 2 O 3 –ZrO 2 rose rapidly when the temperature increased to a certain value.