Paper number 587
|ENERGY ABSORPTION DURING FLEXURAL FAILURE OF LAYERED METAL FOAM / CERAMIC COMPOSITES|
A.E.Markaki and T.W.Clyne
Department of Materials Science, Cambridge University,
Pembroke Street, Cambridge CB2 3QZ, UK.
|Summary||Laminates consisting of alternate layers of Al2O3 and foamed Al alloy have been prepared using a hot-pressing technique. The foamed metal constituent was either Al-7Si or Al-12Si-0.6Mg. Mechanical tests have been performed using several specimen configurations. These include laminate flexure and constrained tensile fracture of single metal foam layers. Comparisons are presented between measured fracture energies during bending and predictions based on the deformation behaviour of bridging ligaments. The deformation characteristics of multi-layer laminates and single constrained foam layers are compared with those observed for dense metal layers of the same composition. It was found that the fracture energy of the laminates increased with increasing proportion of the foam layers, as predicted theoretically. Part of the energy is absorbed by plastic deformation of the metallic constituent, as with fully dense laminates, but there is some evidence that another process, such as frictional sliding at the interface, may also have made a significant contribution.
||Keywords|| metallic composites, foams, porosity, layered structures.
Theme : Metal Matrix Composites ; Thermo-mechanical behaviour
[ HOME ] [ BACK ]