J. F. Despois

Microstructural tailoring of open-pore microcellular aluminium by replication processing

The replication process is presented and discussed with emphasis on methods for microstructural tailoring of open-pore microcellular aluminium-based foams, highlighting methods it offers for control of principal foam mesostructural and microstructural parameters: pore volume fraction, pore shape, pore size(s), as well as the composition and microstructure of the metal making the foam.

Structural Metallic Materials by Infiltration

An overview is presented of current research at EPFL on structural metallic materials produced by infiltration processing. The paper comprises a brief introduction to the infiltration process, then presents results on particle reinforced metals and open-celled aluminium foams.

Uniaxial deformation of microcellular metals: model systems and simplified analysis

Microcellular aluminium can be produced by a process known as replication; this involves the infiltration of a packed bed of NaCl particles which are subsequently leached after metal solidification. The resulting material features a uniform distribution of equisized pores, the shape and volume fraction of which can be tailored, as can the composition and microstructure of the metal making the resulting metal “sponges”. These display a regular uniaxial stress-strain behaviour, at both room and elevated temperature, which is interpreted using standard composite models for Young’s modulus coupled with variational predictions for non-linear deformation of two-phase composites by Ponte-Castaneda and Suquet, adapted and simplified for the specific case at hand.