Effect of oxygen content on
tensile strength of
polymer-derived SiC fibers
tensile strength of
polymer-derived SiC fibers
(State Key Laboratory of New Ceramic Fibers and Composites,
School of Aerospace and Materials Engineering,
National University of Defence Technology, Changsha 410073, China)
School of Aerospace and Materials Engineering,
National University of Defence Technology, Changsha 410073, China)
Abstract: Air-curing is usually applied to the polymer-derived SiC fibers and, as a result, oxygen is embedded to the material. An effective relationship between oxygen content of the SiC fibers and mass gain of their precursor fibers was established. Results also showed that oxygen content has a great influence on the mechanical properties and excellent tensile strength is usually obtained at the oxygen content of 12%~13%, similar to the density of SiC fibers. Oxygen content has a positive effect on the ceramic yield, and thus, is good to the density and tensile strength; while, oxygen content is also negative to volume content of SiC phase and crystallization of the SiC fibers, and thus, detrimental to the density and tensile strength. Both of the two effects result in the peak behavior of the tensile strength of SiC fibers.
Key words: SiC fiber; oxygen content; mechanical property; polymer-derived ceramic