Low temperature, spark plasma sintering behavior of zirconia added by a novel type of alumina nanofibers

A novel type of alumina nanofibers has been used for fabrication of the alumina toughened zirconia composites and the effect of different sintering techniques on the characteristics of the material was studied. ZrO2–10 vol% Al2O3 composite was consolidated by spark plasma sintering (SPS) in a temperature range from 1000 °C to 1200 °C and by pressureless sintering in air at 1300 °C. Dilatometry sintering of the said composite material was performed in order to assess its sinterability. Al2O3 used in fabrication of the composite is a novel type of alumina nanofibers and thus the effect of different sintering techniques on the formation of the material was investigated. Microstructural analysis has revealed that Al2O3 nanofibers partially retained their fiber states after being sintered at 1100 °C under SPS conditions while some of the fibers turned into rounded inclusions. Specimens produced by the SPS routine at temperatures of 1100 °C and 1200 °C were consolidated 93% of theoretical density while the same material sintered with the conventional PM method in air had a densification degree of 74%.