Stresses during Fabrication of Cylindrically Woven Carbon-Carbon Composites

摘要

Carbon-carbon billets sometimes experience failure during fabrication. In order to understand the stresses causing these failures, we have modeled the elastically anisotropic billet as an assembly of very thin-walled, isotropic cylinders. Alternate cylinders have different properties; one set models the fibers, the other the matrix. The assembly has cylindrical anisotropy and permits simple calculation of the thermal stresses of fabrication. The stresses are calculated for the billet after cracks have been filled with pitch and reheated. A fabrication microcracking morphology is presented and the causes of this cracking discussed. The benefit of adding circumferential fibers to the inner and outer diameters is shown. (Author)