Densification of CuO-ZrO2 Nanocomposites by Flash Sintering

This study is a comprehensive investigation into CuO-doped ZrO2 nanoparticles (NPs) produced by the hydrothermal method and its conventional (CS) and flash-sintering (FS) processes. Besides this production, the effect of the differences in sintering techniques and density was investigated to prove the results. However, to the authors’ knowledge, the FS of CuO/ZrO2 nanocomposite (NC) material has yet to be studied, which is the first report on this material. The CuO/ZrO2 nanocomposite particle (NCP) pellet was sintered at 1250 oC for 1 hour using CS. The other sintering method is FS, which obtains highly dense NCs. The CuO/ZrO2 NCPs pellet was successfully produced with the lower sintering temperature (673 oC) and duration (60 seconds) by FS under a current density of 50 mA/mm2, and electric field (100 V/cm). The microstructure and density of the pellets produced from CS and FS experiments were evaluated. The SEM results showed that the CuO/ZrO2 NCPs with the FS experiment were successfully performed, and density results with 4.38 g/cm3 proved this success compared to CS pellet density (3.72 g/cm3). The FS process for CuO/ZrO2 NCPs consumes ~ 2.2 kJ (0.227 kJ/cm³), whereas CS samples require ~ 13 kJ (54 kJ/cm³), making FS approximately six times more energy-efficient. This significant reduction in energy consumption highlights FS as a promising method for future applications focused on carbon emission reduction and energy efficiency.