ZIRCONIA (ZrO₂) :

Zirconia exhibits a crystallographic evolution as a function of its temperature. During its shaping and cooling, between 1000 and 1100°C, the quadratic phase becomes monoclinic. This crystallographic transformation is accompanied by a volume variation of 3% which can be damaging to the material. This damage characteristic of pure zirconia is an issue. This is why it is common to use additives (dopants) that stabilize the cubic or quadratic form of zirconia at room temperature (MgO, CaO, Y₂O₃, …).

Zirconia partially stabilized with yttrium (Y-TZP) offers an extraordinary resistance to mechanical shocks and bending, because of their high tenacity and its relative "elasticity". This material is a technical ceramic of choice for severe mechanical applications. Other grades are fully stabilized for high temperature applications.  

Characteristics :

Y-TZP zirconia have the Following characteristics :

• High density
• High flexural strength
• High toughness
• Good wear resistance
• Low thermal conductivity (10 times lower than alumina)
• Good resistance to thermal shock
• Good chemical resistance
• Good electrical conductivity at high temperature - Electrical insulator at low temperature
• Fine surface finishes achieved
• High thermal expansion (similar to steel)

Applications :

Zirconia is a ceramic widely used in the following applications :

• Pistons and valves for pumps - spray nozzles

• Tubes and sealing rings

• Wearing parts

• Component of metrology equipments (antennas, pressure sensors, …)

• Cutting tools (blades, …)

• Dental implants

• Medical materials

• Nuclear field