ABSTRACT

Development of novel radiopaque adhesive allowed voids to be seen in an adhesive/sealant sandwiched between aluminum parts. The adhesive had to be platable using the same etching processing as for the composite parts. An epoxy adhesive, Epiphen 825A, was used to bond the aluminum parts together and simultaneously seal the joints to provide an air-tight seal. The goal is to formulate a radiopaque adhesive based upon Epiphen 825A adhesive, which would still retain its most important adhesive properties including good processing characteristics, high lap shear strength, and non-outgassing properties. The concept of formulating a radiopaque adhesive, which allows the non-destructive inspection of bonded joints within aluminum parts, was both theoretically and experimentally proven to work. The good processing characteristics of the radiopaque adhesive were maintained, and the lap shear strength of the radiopaque was equivalent to the original adhesive. Both values easily passed the specification requirement.