High Resolution Optical Interference Investigation of Swelling Due to Water Uptake by Model Adhesive Joints

Publisher Website
Google Scholar
Abstract
Fully cured resin adhesives swell when they absorb water. By manufacturing a model butt joint between a thin, and therefore flexible, microscope cover slip as one adherend and a massive, and therefore rigid, slab of glass as the other adherend, development of the swelling can be observed and measured by generating Moire images from photographs of the pattern of optical interference fringes formed in the gap between an optical flat and the free surface of the cover slip. The swelling is strongly inhomogeneous and this inhomogeneity gives rise to a distribution of stress normal to the joint which is compressive near both the rim and centre, and tensile within an annular region located between the rim and centre. It has been demonstrated that swelling stresses large enough to cause fracture of the cover slip can be developed. Regularly spaced radial perturbations in the boundary between unswollen and swollen adhesive have been observed in a film which contains a carrier cloth.

This publication has 0 references indexed in Scilit: