A study on fiber/matrix contour and interface/interphase integrity by SEM and AFM techniques

Abstract

The characterization of fractographic features associated with fibers, matrix and also interface/interphase has been emphasized here to analyze the surface topographical contours across the glass fiber and epoxy matrix. Atomic force microscope (AFM) and Scanning electron microscope (SEM) were performed to characterize the micro-failure features (like micro-voids, small matrix and interfacial cracks ) and structural homogeneity/integrity of composites. AFM study showed that thermal conditioning has resulted non-homogeneous degree of cross-linking reflected by the height-scan images. The uneven post-curing may adversely affect the stress transmissibility integrity of interphase region, which may eventually lead to changes in thermophysical, mechanical and chemical characteristic of fibrous composite. Scanning micrograph indicates the increase in cusp thickness due to increase in plasticity of resin matrix.