INFLUENCE OF HERMETIC COATING ON MECHANICAL PROPERTIES OF SILICA GLASS FIBERS

摘要

An influence of two types of hermetic coatings (metal coating from melt and pyrolytic carbon coating) on mechanical properties of silica glass fibers was studied. In case of metal coating the residual water under metal coating can reduce long-term reliability at medium temperatures and an interaction of metal with glass can Limit time-to-failure at high temperatures. At room temperature the strength of carbon-coated fibers practically does not depend on the drawing conditions and is determined by the properties of carbon coating. Strength of weak carbon coated fibers with melted-in zircotna particles was also investigated. It turned out to grow with increasing carbon thickness. When the carbon coating was thick enough, fiber strength did not practically depend on coating thickness and environment humidity and was more than two times higher than that for polymer coated samples.