Speakers
Description
Zirconia and alumina are widely used for wear-resistant components, while zirconium oxide also serves as a thermal barrier material. Diamond, with the highest thermal conductivity among all materials, can potentially improve the thermal shock resistance of zirconia. However, producing oxide–diamond composites is challenging due to the high sintering temperatures required for ZrO₂ and the tendency of diamond to graphitize under pressureless or low-pressure conditions. Direct sintering may also cause oxide reduction, carbon monoxide formation, and poor bonding between zirconia and diamond.
In this study, ZrO₂–30 wt% diamond composites were produced indirectly. Zirconium powder with 3 mol% Y₂O₃ and 30 wt% diamond powder was milled for 8 h in a planetary mill using zirconia milling media, enabling zirconium deposition on diamond surfaces. The powders were oxidized at 600 °C for 1 h and this process was repeated three times with intermediate mixing.
Sintering was carried out at 1250°C for 4 min in air using Spark Plasma Sintering. X-ray diffraction showed that the matrix mainly consisted of tetragonal ZrO₂, with minor monoclinic ZrO₂ and ZrO₃ phases. Microstructure was analyzed by X-ray computed tomography, while thermal diffusivity and conductivity were measured using the laser flash method.
| Professional Status of the Speaker | Doctoral or Master Student |
|---|---|
| Invitation letter for visa | No |
| Interest in submitting a paper in a special issue of | Journal of the European Ceramic Society (Elsevier) |
