Experimentation on adhesion of epoxy

In a recent article (Sekulic and Curnier (2007) [1]), an original axisymmetric epoxy-stamp on glass-disc specimen, which exhibits stable debonding, was presented for identifying the adhesive properties between epoxy and glass, namely interface debonding energy ωω, adhesion peak stress πnπn and debonding rupture gap γnγn.In this article, the theoretical bases, experimental qualities and practical utilities of that specimen and experiment are discussed, demonstrated and illustrated.It is experimentally established that weak debonding stability (oscillatory secant increase of traction force with specimen elongation in the mean over debonding range) is determined by the slope of the epoxy-stamp radial profile, and that (strong) debonding stability (monotonous increase at each elongation along debonding range) is further determined by the glass-disc stiffness, hence by its thickness.It is demonstrated that a conical or parabolic or optimal blend epoxy-stamp on stiff-disc specimen can be reliably used to study adhesion of epoxy (and other glues) on plexiglas, glass, aluminium and steel (and many other materials).