LAUSR

Abstract Uni-axial compressive failure of silica-epoxy based heterogeneous honeycombs is investigated in detail for a range of volume fractions. Introduction of heterogeneity in compression of staggered-square honeycomb is seen to result in damage initiation at multiple locations and subsequent damage growth to be more stable compared to pure epoxy in which damage was observed to be localized until peak load when catastrophic failure of the honeycomb specimen occurs. The increase in stiffness and comparative stability of the response is accompanied with reduction in strength, however, between 0 and 5% the total work of compressive failure is comparable. From the elastic-plastic analysis it is evident that the non-linearity in the response of pure honeycombs, prior to peak load, is largely due to formation of plastic hinges near corners of cells, whereas in case of heterogeneous honeycomb the non-linearity is mostly due to debonding of hard filler particles and matrix cracking leading to damage growth in cell walls.