Ceramics have played an important role historically in the evolution of industrial design and are considered to be the engineering materials of the future.
Ceramic materials are derived from naturally-occurring inorganic materials such as clay minerals and quartz sand. Through production processes that have been developing through centuries, ceramics are used to create a wide variety of products that include china tableware, bricks, industrial abrasives, tiles, refractory linings and even cement.
The last 20 years have seen the development of a new breed of high-tech engineering ceramics, with numerous industrial applications ranging from combustion engine components to oxygen sensors. These new materials are completely different from traditional ceramics because they include in their composition metallic powders such as alumina, titania, yttria and zirconia.
Zirconia Ceramic is a ceramic material consisting of at least 90% of Zirconium Dioxide (ZrO2). It is produced from natural minerals such as Baddeleyite (zirconium oxide) or zirconium silicate sand. Zirconia Ceramics are used in orthopaedics since 1985. When designers were seeking for new materials, zirconia ceramics were used to create different products. An early study for zirconia ceramics was carried out by Richard Seymour who created blades for kitchen knives.
This material has the highest strength and toughness at the room temperature of all engineering ceramics. Before zirconia, ceramics were considered impractical for scissor of knife application.
• High density – up to 380 lb/ft³ (6.1*10³ kg/m³);
• Low thermal conductivity – 10% of that of alumina ceramics;
• High fracture toughness;
• Very high flexural strength and hardness;
• High maximum service temperature – up to 4350 ºF (2400 ºC).
• Coefficient of thermal expansion similar to that of cast iron;
• Modulus of elasticity similar to steel;
• High chemical resistance;
• High resistance to molten metals;
• Good wear resistance;
• Low coefficient of friction.
Zirconia ceramics are used for manufacturing:
- Extrusion dies;
- Powder compacting dies;
- Cutting tools;
- Balls and seats for ball valves;
- Thread and wire guides;
- Pump seals;
- Impellers and shaft guides;
- Engine parts;
- Oxygen sensors;
- Fuel cells membranes;
- High temperature heaters for electric furnaces;
- Bearings (e.g., bearings for submersible pumps).