The effect of core thickness on the flexural behaviour of aluminium foam sandwich structures

The effect of core thickness on the deformation mechanism of an aluminium foam core/thermoplastic composite facing sandwich structure under 4-point bending was investigated. Full field strain analysis and visual observations show a number of failure mechanisms between the different core thicknesses. High strain concentrations were observed in each sample thickness corresponding to the particular region of failure. The thinner samples exhibited skin wrinkling and fracture, and some core cracking and crushing while the thicker samples failed due to core indentation. Increasing the skin thickness eliminated the incidence of core indentation. Instead, significant core shear cracking was observed.