Influence of Loading Rate and Processing Atmosphere on Pullout of SiC Fibers from Pyrex Glass

The interfacial shear strength of SiC/glass composites fabricated either under vacuum or in argon gas by hot-pressing was estimated using a single-fiber pullout test as a function of the loading rate. The interfacial shear strength of the composite fabricated under vacuum depended insignificantly on the loading rate. On the contrary, for the composite fabricated in argon gas, loading rates strongly influenced the interfacial shear strength as well as the interfacial debonding behavior. The influence of loading rates on the interfacial shear strength in the latter composite could result from the presence of the Si-O bond, whose strength is affected by slow crack growth along the fiber-matrix interface. These results indicate that the fracture behavior of fiber-reinforced ceramics whose interfacial shear strength depends on the loading rate can differ widely under dynamic and static loading.