Adhesive failure with adherend yielding: The T-peel test and cohesive zone modeling

The T-peel test was analyzed using the analytical adhesive joint model developed by Wang [68]. The mechanical properties of the bulk adhesive were measured experimentally. It was shown that the T-peel test is equivalent to a flexible-rigid peel test with a thinner adhesive layer.;Wang's model was then modified by applying a cohesive zone model (CZM) which was utilized for modeling the peel test. The optimum traction-separation curves were first obtained by analyzing DCB tests. A failure criterion was introduced for the CZM model which was shown to be a function of peel angle and peel arm thickness as independent variables. The loading zone length (length of bondline carrying significant peel load) was used to find this relation. The function was derived with the aid of multiple regression and used to predict the peel forces for 9 peel configurations. The predicted peel forces were compared to those of experiments with an average error of 7%.;Finally, the T-peel test was analyzed using the CZM code and the adhesive thickness of the equivalent peel test was calculated.