Ceramics have exceptional thermal properties compared to metals and plastics. Thermal expansion is low for all types of ceramics. Other properties, such as thermal conductivity, resistance to thermal shock and resistance to extreme temperatures, vary from one group of ceramics to the next.
Description
The coefficient of thermal expansion of a solid, denoted by α (unit: 10-6.K-1), is the ability of a material subject to temperature change to expand or contract (atomic vibration amplitude of the structure). Generally, ceramics expand when heated and conversely contract when they are cooled. The lower the coefficient of thermal expansion, the less the material will change its shape.
Stiff materials (high Young's Modulus), such as ceramics, expand less than metals and polymers.
Application markets
These materials are used in a wide variety of sectors: aeronautical and spatial, energy, electronics, transport, defence, engineering (equipment manufacturers, special machines, processing equipment), etc.
Comparative table of properties
Comparative table of thermal properties :
| Linear thermal expansion coefficient 25-1000°C (10-6.K-1) | Thermal conductivity (W/m.K) | Maximum operating temperature (°C) in air | Thermal shock resistance | |
| Alumina (94%-99,8%) | 7,5 to 9,5 | 18 to 30 | 1500 to 1700 | + |
| Alumina-zirconia composites | 8 | 25 | 1500 | ++ |
|
Zirconia MgO & Y-TZP |
10 | 2 to 2.5 | 1000 to 2000 | ++ |
| Aluminium nitride | 5.5 | 140 to 180 | 800 | ++ |
| Sentered silicon carbide | 4 to 5 | 80 to 125 | 1400 to 1900 | +++ |
| Sentered silicon nitride | 3 to 4 | 20 to 25 | 1200 to 1500 | +++ |
| Quartz | 0.5 | 1.5 | 950 to 1150 | - |
| Glass-ceramics | 13 | 1.5 | 800 | - |
Acceptable: + ; Good: ++ ; Very good: +++
These values are for information only and do not constitute a contractual obligation.