Investigation of Static and Fatigue Behavior of Honeycomb Sandwich Structures Under Bending Load

Abstract

The static and fatigue failure behavior of honeycomb sandwich structures have been experimentally investigated in this paper. Three point bending static and fatigue tests were used for assesment of flexural rigidity and fatigue life. Under displacement control monotonic load, the load and mid span displacement response corresponds to five different phases. The fatigue life of the panel is evaluated by performing the constant amplitude load at the several loading levels. The results show that fatigue life increases as the stress level decreases. The visual and optical analysis were performed to analyze static and fatigue failure behavior. The fracture modes were analyzed using Scanning Electron Microscope (SEM). It was investigated that the sandwich structures subjected to three point bending load fail in various ways including face yield, compression of face sheet, core shear failure and delamination at core and face sheet interface depending upon the loading conditions. However it is concluded that the final failure under static load occurs due to the compression of face sheet at the loading area and under fatigue load the failure is due to the compression of facing as well as debonding at core and face sheet interface