Static and Fatigue Behaviour of Hexagonal Honeycomb Cores under In-plane Shear Loads

Abstract

Due to their high specific strength and high specific stiffness properties the use of honeycomb panels is particularly attractive in spacecraft structures. However, the harsh environment produced during the launch of a satellite can subject the honeycomb cores of these sandwich structures to severe quasi-static and dynamic loads, potentially leading to static or early fatigue failures. Knowledge of the static and fatigue behavior of these honeycomb cores is thus a key requirement when considering their use in spacecraft structural applications. This paper presents the findings of an experimental test campaign carried out to investigate the static and fatigue behaviors of aluminum hexagonal honeycomb cores subject to in-plane shear loads. The investigation involved carrying out both static and fatigue tests using the single block shear test method. These results are also discussed in relation to the observed damage and failure modes which have been reported for the statically tested specimens and for the fatigue tested specimens at various stages of fatigue life. As well as conducting tests for the more conventional principal cell orientations (L and W), results are also presented for tests carried out at intermediate orientations to investigate the variation of core shear strength with loading orientation. The results are further investigated using explicit non-linear finite element analysis to model the buckling failure mechanisms of the tested cores.

Prediction of static and low-cycle durability of porous cellular structures with positive and negative Poisson's ratios

“…Little fatigue-life data is available for classic-and chiral-auxetic structures [8] and the fatigue-life data of honeycomb structures are mostly available for composite structures with honeycomb cores [9,10]. For this reason a comparison between the low-cycle fatigue properties of the three above-mentioned planar cellular structures has been carried out here.…”

Fatigue behavior of wood-fiber-based tri-axial engineered sandwich composite panels (ESCP)

“…The fatigue strength is dependent of the kind and amount of adhesive applied but the thickness of face sheet is not influential (Jen et al 2009a,b). The failure mechanisms of composites have been investigated also by in-plane shear load-fatigue tests (Bianchi et al 2012). The fatigue properties of engineered strand lumber and engineered strand panels have been studied and it was demonstrated that these materials could easily survive 10 6 load cycles if loaded to < 40% ultimate strength levels (Eckelman and Winandy 1978).…”

Experimental and numerical analysis of the shear nonlinear behaviour of Nomex honeycomb core: Application to insert sizing

“…Pan et al [26,27] analysed the shear buckling of aluminium honeycombs and proposed improved analytical methods for calculating the buckling load. Bianchi et al [28] analysed the nonlinear responses of honeycomb made of aluminium in shear experiments and proposed finite element modelling with initial imperfections. The analysis also focused on their behavior in the orthotropic or off-axis directions.…”