THERMAL STABILITY AND CHEMICAL CORROSION RESISTANCE OF NEWLY DEVELOPED CONTINUOUS Si-Zr-C-OTYRANNO FIBER

摘要

A new continuous inorganic fiber, Si-Zr-C-0 fiber, containing zirconium instead of titanium (Si-Ti-C-O fiber), has been successfully developed. This new Si-Zr-C-O fiber exhibits improved thermal stability and chemical corrosion resistance and has a decreased oxygen content. This reduction in oxygen content of Si-Zr-C-0 fiber can be achieved by changing additives, from titanium alkoxide to a zirconium complex during the polymerization process of the precursor polymer. Continuous Si-Zr-C-O fiber "ZM" and "improved ZM" produced by oxidation curing had oxygen contents of 10 and 7.6 wt percent, respectively. The oxygen content of "ZE" produced by electron beam curing was reduced to 1.7 wt percent. The thermal stability and oxidation resistance of both ZM fiber and improved ZM fiber were superior to those of Si-Ti-C-O fiber (LoxE) produced by electron beam curing which has an oxygen content of only 5wt percent. The crystalline grain growth of ZM fiber up to 1773KAPPA for 1 hour in argon gas and the level of decomposition of ZM fiber during heat treatment in CO gas at 1773KAPPA for 3 hours were very low in comparison with those of LoxM fiber (Si-Ti-C-O) by oxidation curing and LoxE fiber. Furthermore, concerning chemical corrosion resistance, when ZM and LoxM fibers were immersed in salt(NaCl) water and then heat treated at 1273KAPPA in air for 2 hours, LoxM fiber containing titanium was considerably damaged, but ZM fiber exhibited minimal damage.