High stability structures are required to provide the supporting framework for high precisión space based instruments. In addittion, these instruments shall be lightweight and withstand extreme environmental conditions i.e. vacuum, low (even cryogenic) temperatures or large temperature fluctuations, high mechanical loads imposed during launch. Therefore, key properties of candidate materials for these components include:
- Low CTE (Coefficient of Thermal Expansion, oover wide temperatura range).
- Low density.
- High strength and stiffness.
- Homogeneous and consistent manufacturing.
- Polishable Surface and/or compatibility with a polishable coating.
- High thermal conductivity.
At the moment, none of the materials currently in use can adequately satisfy all these requirements.
The CINN has developed composites with tailored, including null, CTE. Using this approach ceramic nanocomposite materials with non-oxidic second phases and showing a CTE lower than 1×10-6 K-1 in the temperature range (-150 ºC +150 ºC) can be obtained by a simple process that comprises conventional sintering methods, thus opening the possibility of manufacturing components with complex shapes and large dimensions. The patent portfolio also includes materials with only oxidic components and tailored thermal expansion coefficient, including materials with zero thermal expansion. These materials can be used in oxidizing atmospheres at elevated temperatures while maintaining excellent mechanical properties.