Fracture characteristics of mixed-mode toughness of dissimilar adherends (cohesive and interfacial fracture)

This paper investigates the fracture behavior of aluminum/polymer dissimilar adhesively bonded joints at different mixed-mode ratios. For this purpose, a series of experiments were carried out using a modified Arcan fixture to obtain critical fracture load in mode I, mode II and mixed-mode, for two types of cohesive and interface starter cracks. Experimental data, along with the Virtual Crack Closure Technique (VCCT) were employed to extract the strain energy release rates. The average values of strain energy release rates were found and for cohesive cracks, and and for interface cracks. Considering the relations between the strain energy release rate and the stress intensity factor, and were also calculated for cohesive and interface starter cracks.