Thermal Expansion
Thermal Expansion
Advanced ceramics have generally low coefficients of thermal expansion which is the measure of how much a material expands due to a rise in temperature.
When heat is applied to most materials they expand due to their atomic structure, ceramics due to their atomic composition are able to stay stable across a wider range of temperatures. Advanced ceramics have half the coefficients of thermal expansion when compared to metals like stainless steel, and this low thermal expansion can be used to advantage on designing assemblies where ceramics can be kept in compression to enhance its mechanical strength.
Important Materials for Thermal Expansion
(CTE 25°C ➞ 400°C)
In terms of thermal expansion, Zirconia and Alumina rank on the higher end and Silicon Nitride and Silicon Carbide are on the lower end. With a range of materials and grades in our portfolio with varying characteristics, materials like Shapal Hi M soft with its close expansion match to silicon works well in semiconductor applications.
Aluminum Nitride (AlN) – CeramAlum™ PCAN1000
4.5 [10-6/K]
PCAN1000 is our standard high purity aluminium nitride with a thermal conductivity of 170 W/ (m.K). This is the same thermal performance as our substrate material but offers the possibility of larger pieces in length and width and in thicknesses up to 30mm.
Shapal Hi M Soft™ - Machinable AlN
4.8 [10-6/K]
Shapal Hi-M Soft is a hybrid type of machinable Aluminum Nitride (AlN) ceramic that offers high mechanical strength and thermal conductivity.
Alumina (Al2O3) – CeramAlox™ Ultra Pure
7.5 [10-6/K]
CeramaAlox Ultra Pure is a very high purity (99.95%) grade of Alumina (Aluminum Oxide) exhibiting an exceptional combination of mechanical and electrical properties.
Zirconia (ZrO2) - CeramaZirc™ Ultra Tough
10 [10-6/K]
CeramaZirc Ultra Tough is an advanced zirconia-based ceramic composite material based on partially stabilized zirconia and alumina platelets.
Related Properties
Fracture Toughness
The ability to resist fracture is a mechanical property of materials known as fracture toughness. For advanced ceramics it uses a critical stress intensity factor known as KIC where the fracture normally occurs at the crack terminations.
Density
Density is the mass of a material per unit volume. The unit of measurement can be expressed in different ways and is referred us as g/cm3 but another measurement value is kg/m3.
Hardness
One of the most valuable characteristics of advanced ceramics in high-performance applications is their extreme hardness. Hard ceramic materials are used for a wide range of applications in diverse fields and applications such as cutting tools for milling and grinding.