High-temperature creep and microstructural evolution of chemically vapor-deposited silicon carbide fibers

The creep behavior of three types of silicon carbide fibers that have been fabricated via chemical vapor deposition is described. The fibers exhibit o nly primary creep over the range of conditions studied (1200 degrees-1400 d egrees C, 190-500 MPa). A transmission electron microscopy study of the mic rostructural development that is induced by the creep deformation of SCS-6 silicon carbide fibers at 1400 degrees C is presented. Significant grain gr owth occurs in all silicon carbide regions of the fiber during creep, in co ntrast to the reasonably stable microstructure that is observed after annea ling at the same temperature and time.