Investigation of the Mechanical Properties of Interphases in Adhesively Bonded Epoxy-Aluminum Joints by Localized Micro Extensometry

Abstract

In recent papers it has been reported that epoxide-based adhesives form so-called interphases in adhesive joints. The properties of these interphases play an important role concerning the performance and durability of structural adhesive joints under detrimental service conditions. In this paper, the formulation of a basic epoxy adhesive and a methodology for gaining insight into the local mechanical properties of polymer interphases in structural adhesive joints made with ambient temperature curing epoxy adhesive are presented. The localized strain analysis in the cross-section of shear-loaded adhesive joints is accomplished by combining a high precision micro tensile tester with a digital microscope and by developing a method for preparing, marking, and digitally tracking the local deformations in a micro shear specimen.

KEYWORDS:

• Adhesive joints
• Epoxy
• Interphase
• Micro-shear-specimen
• Strain softening
• Stress-strain-analysis

Notes

One of a collection of papers honoring Wulff Possart, the recipient in February 2012 of The Adhesion Society Award for Excellence in Adhesion Science, Sponsored by 3M