High-Temperature Creep and Microstructural Evolution of Chemically Vapor-Deposited Silicon Carbide Fibers

Abstract

The creep behavior of three types of silicon carbide fibers that have been fabricated via chemical vapor deposition is described. The fibers exhibit only primary creep over the range of conditions studied (1200°-1400°C, 190-500 MPa). A transmission electron microscopy study of the microstructural development that is induced by the creep deformation of SCS-6 silicon carbide fibers at 1400°C is presented. Significant grain growth occurs in all silicon carbide regions of the fiber during creep, in contrast to the reasonably stable microstructure that is observed after annealing at the same temperature and time.