Zirconias
Zirconias are ceramic materials composed primarily of zirconium dioxide (ZrO₂), often with stabilizing additives such as yttria (Y₂O₃) or magnesia (MgO). Pure zirconia has a high melting point, low thermal conductivity, and excellent mechanical strength, but it is also prone to cracking during cooling from the melt. The addition of stabilizers suppresses the high-temperature cubic phase, resulting in a mixed-phase microstructure that is resistant to thermal shock and hydrogen embrittlement.
The most common commercial form is 3 mol% yttrium‑stabilized zirconia (3Y‑SZ), which shows a notable transformation‑toughening
Zirconias are produced by powder processing: raw materials are mixed, calcined, and then shaped by pressing
Applications of zirconias include dental crowns, bridges, and fillings, due to their biocompatibility, stain resistance, and