Zirconia Ceramic Seals
Zirconia is an extremely refractory material. It offers chemical and corrosion inertness to temperatures well above the melting point of alumina. The material has low thermal conductivity. It is electrically conductive above 600°C and is used in oxygen sensor cells and as the susceptor (heater) in high temperature induction furnaces. With the attachment of platinum leads, nernst glowers used in spectrometers can be made as a light emitting filament which operates in air.
Key Properties of Zirconium Oxide
• Use temperatures up to 1000°C
• High density
• Low thermal conductivity (20% that of alumina)
• Chemical inertness
• Resistance to molten metals
• Ionic electrical conduction
• Wear resistance
• High fracture toughness
• High hardness
Typical Uses of ZrO2
• Precision ball valve balls and seats
• High density ball and pebble mill grinding media
• Rollers and guides for metal tube forming
• Thread and wire guides
• Hot metal extrusion dies
• Deep well down-hole valves and seats
• Powder compacting dies
• Marine pump seals and shaft guides
• Oxygen sensors
• High temperature induction furnace susceptors
• Fuel cell membranes
