Two types of SiC fiber tows (Hi-Nicalon™ and Hi-Nicalon S™) were coated with stabilized ZrO
and composited using preceramic polymer impregnation pyrolysis to form SiC/SiC
minicomposites. Properties of the fiber/matrix interface in composites were investigated using the indentation method in which a pyramidal indenter was used to push on an individual fiber and cause sliding at the interface. The interfacial frictional stresses were determined from the force-displacement relation. The composites reinforced by the ZrO
-coated fibers have smaller interfacial frictional stresses than composites reinforced by the initial fibers and show fibers sliding relatively more easily with respect to the SiC matrix.