Silicon carbide is a high temperature-resistant material. Due to its thin protective layer consisting of SiO2 it is passivated against oxidation and corrosion up to temperatures of approximately 1650 °C. Under vacuum or inert gas SiC is stable up to 2000 °C. The good thermal conductivity and the low coefficient of thermal expansion are the basis for a good thermal shock resistance of many SiC ceramics.
The loads occurring in high-temperature applications are often very complex so that a test under operating conditions is indispensable in most of the cases. Secondary phases also change the high temperature properties of some SiC materials, e.g. of LPS-SiC and SiSiC, in a specific way. SiC is inert in contact with solvents and aggressive chemicals; in acids and alkaline solutions it is even one of the most resistant ceramics. Only in contact with some molten salts or metals at high temperatures SiC corrodes.
These properties are the reason why SiC components are widely used as burner nozzles, burning aids in form of rolls, bars and plates as well as seals, bearings and protective sleeves in chemical industry.
Products and services offered
- Material selection and component development for the application under extreme conditions (temperature, corrosion and wear)
- Material modification for specific application requirements
- Chracterization and test of silicon carbide ceramics under extreme loads
- Postmortem and damage analysis
- Complete technology and equipment for materials development and component manufacturing
- Test sites for corrosion, wear and high temperature
Examples and references
- Characterization and increase of the oxidation resistance of burner components
- Hydrothermally resistant LPS-SiC for bearings
- Damage analysis on seal rings and pump components