Interphase Debonding in High Temperature Ceramic Composites

摘要

Studies aimed at understanding the role of the interphase in providing a nonlinear response in oxide composites are described. Debonding and sliding of single crystal and eutectic oxide fibers coated with La-monazite caused intense plastic deformation of the LaPO4 at room temperature. Such plastic deformation mechanisms could be critical for preventing the development of very high stresses during constrained sliding of rough interfaces. A new class of machinable two-phase ceramics based on the debonding and deformation characteristics of rare-earth phosphates was demonstrated. Multilayered composites, consisting of various zirconia-based materials alternating with layers of LaPO4, were fabricated for studies of compatibility and debonding mechanisms.