Study on 180o Peel Test of Interface Adhesive Honeycomb Sandwich Structure

Abstract

180o Peel experiment was designed and performed to estimate the peel strength parameters and failure modes of the interface adhesive Honeycomb Sandwich Structure (HSS). The aluminum-lithium alloy honeycomb core and skin specimens were bonded with adhesive according to the adhesive bond strength test standards, and the honeycomb shape is hexagon. 180o peel test was conducted using the designed fixtures so as to compare the peel strength and failure form of the adhesive layer. The peel strength was calculated by recording the peel load-displacement curves and observing the destruction of the interface during the experiment. Simultaneously, local strain field, especially at the critical moment of the breakage point, was obtained by digital image correlation (DIC). The results show that failure mode of the HSS with interfacial adhesive is cohesion failure of the adhesive, and the results of numerical analysis are in good agreement with the experiments.