Due to their low mass, accumulated heat and thermal conductivity, ceramic fibre products are efficient insulating materials up to temperatures of 1800 °C. Considering current and future energy costs, amortisation can be realised in a short time.
- Today it is generally possible to produce inorganic fibres out of almost all oxides, carbides, nitrides, metals, carbon and mixtures of these. For high temperature thermal insulation, two groups are to be differentiated: the amorphous and the polycrystalline fibres. With only a few exceptions these ceramic fibres used for heat insulating purposes derive from the binary system Al203 - Si02.
- A derivative fibre type differs in such a way that a share of alumina is replaced by approximately 15 %zirconia (Zr02). Further fibre types are based on the material systems calcium silicate or calcium aluminate with Ca0 contents of approximately 20 to 40 %.
- Unused fibres are glassy and amorphous up to Al203 contents of approximately 60 %. The main components of polycrystalline fibres are microcrystalline. All high temperature fibre types are produced from substances of high purity.
