Recent advances in Nicalon ceramic fibres including Hi-Nicalon type S

Polymer-derived Nicalon SiC fiber produced commercially has been widely applied in high temperature Ceramic Matrix Composites (CMCs). Recently, SiC fiber with a low oxygen content (Hi-Nicalon) was developed and produced commercially using an electron beam curing. This fiber has a higher elastic modulus and creep resistance, and much higher thermal stability up to 1600 degrees C than that of Nicalon fiber High temperature mechanical properties of CMCs with Hi-Nicalon have much improved. However, creep and oxidation resistance of Hi-Nicalon CMCs are not satisfactory for high temperature structural materials, because Hi-Nicalon mainly consists of SIC micro-crystals and excess carbon. Therefore, we have developed an SiC fiber (Hi-Nicalon type S) with stoechiometric SiC composition and high crystallinity. Hi-Nicalon S fiber has high elastic modulus (420 Cpa), good oxidation resistance at 1400 degreesC, and excellent creep resistance, in this paper, the recent development of these oxygen free SiC fibres including physical and mechanical properties, thermal stability and an environmental resistance are reported.