Engineering Ceramics
Engineering (technical) ceramics such as alumina, zirconia, silicon carbide and silicon nitride offer extreme hardness, wear resistance, heat resistance, chemical inertness and electrical insulation. They are used for wear parts, seals, insulators, nozzles and high-temperature components.
What it is
Alumina (Al2O3) is the most common: hard, insulating and economical. Zirconia is tougher and suits cutting blades and valve parts. Silicon carbide excels in abrasion, heat and chemical resistance for seal faces and nozzles. Silicon nitride combines toughness and thermal-shock resistance for bearings.
Ceramic parts are formed and sintered, then diamond ground to tolerance, so near-net design is important.
Typical applications
- Mechanical seal faces
- Wear liners and nozzles
- Electrical insulators and substrates
- Thread guides and textile parts
- Bearing balls and rollers
Materials & grades
- Alumina (95–99.8%)
- Zirconia (Y-TZP)
- Silicon carbide
- Silicon nitride
- Machinable ceramics
Points to consider
- Brittle; avoid sharp corners, stress concentrations and tensile loads.
- Grinding after sintering is costly; design near-net shapes.
- Match thermal expansion when bonding to metals.
- Choose grade by wear, toughness, thermal shock and insulation needs.
Frequently asked questions
What are engineering ceramics used for?
Wear parts, seal faces, insulators, nozzles and high-temperature components where metals would wear or fail.
Which ceramic is toughest?
Zirconia and silicon nitride are much tougher than alumina or silicon carbide.
Can ceramics be machined?
After sintering, only by diamond grinding; some machinable ceramics can be cut with normal tools.