Flash‐sintering behavior of the composites of 3YSZ and graphene oxide

Abstract

AbstractFlash sintering is a novel technique that involves the sintering of green bodies in few seconds at relatively very low furnace temperature as compared to what is required to sinter them conventionally. In the present work, we flash‐sintered composites of 3 mol.% yttria‐stabilized zirconia (3YSZ) and graphene oxide (GO). The main aim of this work was to see if the decomposition or oxidation of carbonaceous materials can be prevented by the high heating rates during flash sintering and if composites of 3YSZ and GO can be processed in air. 3YSZ with 5, 10, and 20 wt.% of GO were prepared and subjected to constant heating rate flash‐sintering experiments where electric field was applied across the sample right from room temperature. A DC electric field of 100 V/cm was applied and the current density was set to 100 mA/mm2. It was observed that GO decomposed from the surface of the samples; however, in the core of samples, GO was retained but was reduced to graphite. Grain size of the 3YSZ phase increased with increase in the GO content, whereas the hardness decreased. It was observed that the composites containing carbonaceous reinforcements need to be flash sintered in inert atmosphere to realize their full potential.