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

摘要

Al2O3-ZrO2 composite ceramic nanopowders were synthesized using a polyacrylamide gel method. The mean particle size of the Al2O3-ZrO2 nanopowders was found to decrease with increasing mole ratio of monomer to the precursor salt. The Al2O3-ZrO2 nanopowders with mean particle size of 10 nm can be densified in 1 h at 965 A degrees C, by application of a dc electrical field. Under a constant dc electrical field, the current density through the sample of Al2O3-ZrO2 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.