The Location of Adhesive Bond Failure by Using Radioactive Tracers

Abstract

The adsorption of several radioactive ions on aluminum surfaces during the surface treatment of coupons for adhesive bonding was SI +7 studied. These were Cr in the FPL chromic-sulfuric acid etch, and Ca , ^Tfa , Fe ions in the rinse water. Calcium was the most strongly adsorbed ion; manganous and ferric ions showed less than \% monolayer coverage. l^CH-Bisphenol A diglycidyl ether was synthesized from labeled bisphenol A and epichlorohydrin, and used in a room temperature curing adhesive to bond 2024 T-3 aluminum lap shear specimens. Autoradiography was performed on coupons with very thin layers of adhesive remaining after tensile failure of the bonded specimens.