The Use of a Modified Mixed Mode Bending Test for Characterization of Mixed-mode Fracture Behavior of Adhesively Bonded Metal Joints

This paper summarizes recent mixed-mode I and II fracture experiments on adhesively bonded metal joints using a modified mixed-mode bending (MMB) test fixture and double cantilever beam (DCB)-type specimens. The MMB test had been previously developed and used for mixed-mode I and II delamination testing of composite laminates, but in the present research it is adapted and modified for fracture testing of adhesively bonded joints with metallic adherends. Strain energy release rates were evaluated by the use of improved analytical models. Mixed-mode fracture behavior of AA5754-0 aluminum alloy specimens bonded with a tough one-part epoxy adhesive (Dow Automotive Betamate 4601 ® ) was characterized.