Development of a new Si-C-O-N-B ceramic fiber using a hybrid precursor of polycarbosilane and polyborosilazane

The development of Nicalon Si-C-O fibers by polymer pyrolysis represents a considerable breakthrough in the field of ceramic matrix composites. However, this kind of SiC-based fiber is metastable at elevated temperatures due to an amorphous SiCxOy phase present in the bulk and much effort is devoted to improve their thermal stabilities. This paper presents a new approach to Si-C-O-N-B fiber by simply blending polycarbosilane (PCS) with polyborosilazane (PBSN), with other techniques same as those of Nicalon fiber.