|
Ceramic
Type
|
Characteristics
|
| Metallic
Oxides |
| Alumina |
- Abundant and easily fabricated.
- Good strength and hardness.
- Wear and Temperature Resistant.
- Good electrical insulators.
- Low dielectric loss.
|
| Beryllium Oxides |
- Exceptionally high thermal conductivities
(for ceramics) at low to moderate
temperatures.
|
| Zirconia |
- Extreme inertness to most metals.
- Good toughness and strength.
|
| Glass
Ceramics
|
| Glass-Ceramics |
- Low, medium or high thermal expansion
depending on composition type.
- Good electrical insulators.
- Transparent
- One can be machined with steel
tools.
|
| Nitrides
and Carbides
|
| Silicon Nitrides |
- Resistant to high temperatures,
to thermal stress and shock.
- High strength and oxidation resistant.
- Good electrical insulators.
|
| Boron Carbide |
- High hardness and low density.
- Best abrasion resistance of any
ceramic.
- Low strength at high temperatures.
|
| Silicon Carbides |
- Low electrical resistivity.
- High strength and resistance to
chemical attack, high temperature
and thermal stress.
|
| Tungsten Carbides |
- Used for tool tips.
- Excellent hardness and mechanical
strength.
- Good thermal conductivity.
- Good wear and abrasion resistance.
|
| Glass
|
| Glasses
- Oxide (silica)
- Silicates
- Phosphates
- Borosilicates
|
- Good resistance to thermal shock.
- Large range of special optical
characteristics.
- Transperent.
- Low thermal expansion and high
dielectric strength.
- Good chemical resistance.
|
| Carbon
and Graphite
|
| Carbons and Graphites |
- Poor strength except when produced
as fibre.
- Good electrical and thermal conductivity
- Creep resistant at high temperatures
in non-oxidizing conditions.
- Self-lubricating.
- Good refractoriness and thermal
shock resistance.
- Low density and chemically inert.
|
| Carbon/Carbon Composites |
- High strength and low coefficient
of thermal expansion at temperatures
above 2000C.
- Excellent thermal shock resistance.
- Superior toughness, excellent
thermal and electrical conductivity
- Resistance to corrosion and abrasion.
- High cost.
|
| Porcelain
|
| Porcelain |
- Good chemical and thermal resistance.
- High density, strength, resistivity
and dielectric strength
- Good thermal shock, wear and hot
strength.
- Chemically inert.
|
| Ceramic
Fibers
|
| Ceramic Fibers |
- Oxides spun to fiber and bulked
to felt.
- Used for high temperature insulation
including former applications of
asbestos.
|
