Keywords: composite materials
Summary:Fiber reinforced composites have heterogeneous structure at multiple length scales. The interface between the fiber and the resin binder is critically important for composite mechanical properties, performance and reliability. It is very difficult to characterize the interface or interphase region in a composite. In order to engineer the interphase region we would like to know the interphase thickness, the modulus and chemical composition in real industrial composite materials. Atomic Force Microscopy and nano-IR have been used to examine Broad Beam Ion Milled composite cross-sections.