Development of heat resistant SiC fibers by radiation curing

For the structural members for advanced big projects, such as space shuttles, high temperature gas turbines, nuclear fusion and so on, high strength, high reliability and environment durability are required for the materials. In the case of space ships, also light weight is required. As the material suitable to these requirements, fiber-reinforced ceramic composites (CMC) attract most expectation and attention. In order to overcome the brittleness of new ceramics, CMC has been developed. As the reinforcing fibers which are mainly used for CMC, there are silicon carbide fibers. They are light weight, and have high strength, high modulus of elasticity and excellent heat resistance and oxidation resistance. In this report, 'Nicalon' of which the practical use is most advanced among SiC fibers and its application to ceramic composites are described. Also 'Hi-Nicalon' of which the heat resistance was further improved by utilizing radiation is introduced. The manufacturing method of SiC fibers 'Nicalon' and their characteristics, the application of Nicalon fibers, Nicalon-reinforced ceramic composites like CERASEP and Nicaloceram, and the development of Hi-Nicalon are reported. (K.I.)