Sintering behavior of ultra-fine Al2O3–(ZrO2 + X mol% Y2O3) ceramics by high-frequency induction heating

Alumina–zirconia composites consisting of Al2O3–20 vol% yttria-stabilized zirconia containing two types of yttria-stabilized zirconia, 3 mol% yttria doped ZrO2 (3YSZ) and 8 mol% yttria doped ZrO2 (8YSZ), were consolidated very rapidly to full density by high-frequency induction heating and sintering (HFIHS). A comparison was made between the sinter behavior and the mechanical properties (hardness, fracture toughness and flexural strength) of the 3YSZ and 8YSZ material. In addition, the consolidated samples were analyzed for phase content by X-ray diffraction (XRD) and the fracture surfaces were examined using a scanning electron microscopy (SEM). The results showed that 3YSZ is most effective as a second phase for the toughening of alumina in comparison to the 8YSZ material. Al2O3–3YSZ composites exhibiting relatively good mechanical properties and limited grain growth were successfully synthesized at relatively low temperatures using this technique.