| An adhesive sandwich model, which treats adherends as bilinear and adhesive as nonlinear, was presented. Both the bending and the shear deformations in adherends were accounted. Stresses and strains in the adhesive were solved from 6 differential equations using a finite-difference method and compared with other models. A reasonable agreement was observed. A peel model was developed using the sandwich model for the attached part of peel joints. Peel tests were conducted on 9 configurations: combinations of 1, 2, 3 mm peel thickness and 30°, 60°, 90° peel angles. Various parameters were calculated and compared with either the finite element models or the experiments. A critical von Mises strain epsilonc criterion and critical fracture energy Gc criterion were proposed. The Gc criterion showed its dependence on phase angles. The load predictions for 9 peel configurations achieved an average discrepancy with experiments of 11% for epsilonc and 5.6% for Gc criterion. |
