Abstract:Preparation of polymer-derived SiC fibers involves a pyrolysis process, in which great weight loss and shrinkage are usually recorded. As a result, stress concentrates on the bend portion of the fibers and then lower their tensile strength. To avoid the bend portion and stress concentration, a pyrolysis under tension, as well as their effect on the tensile behavior of SiC yarns was studied. Results revealed that so-obtained SiC fibers are straight and parallel to each other. The crack load of SiC yarns is much increased, or in another word, their weave capability is much improved.
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