Journal of Adhesion, Vol.43, No.4, 289-288, 1993
NUCLEAR-MAGNETIC-RESONANCE IMAGES (NMRI) OF IN-SITU EPOXY CURING BEHAVIOR IN ANODIZED AND UNTREATED ALUMINUM BONDED JOINTS
Nuclear Magnetic Resonance Imaging (NMRI) was used to analyze the curing behavior of epoxy adhesives in the presence of anodized and chemically-treated aluminum surfaces. The proton images of epoxy between untreated Al plates are characterized by large amounts of inhomogeneities (fine texture of high and low mobility regions) finely distributed throughout the sample. Large uncured domains of epoxy were found aggregated and near the center of the bonded adhesive sample. Dispersion of uncured material during curing is observed through redistribution of intensity in the images with cure time. The anodized aluminum-epoxy samples, on the other hand, showed very small contrast and coarse texture images. However, the onset of curing was clearly shown with increases in contrast and texture. Large amounts of uncured material were seen near the anodized surfaces- This effect was more pronounced in the chromic acid anodized aluminum samples (CAA).
Keywords:INTERPHASES