Metal foams. Properties

Metallic foams belong to the more general group of cellular materials, whose characteristics and properties they share. Nevertheless, they have interesting specific properties, such as a certain isotropy, or the possibility of thermal and electrical exchanges with high specific surface areas.

In addition to the material from which they are made, the characteristics of these materials depend essentially on their porosity levels, as well as on their cell morphologies. Often, to meet the functional needs of designers, the properties established on these products correspond to a macroscopic approach concerning a representative volume of foam. Studies at cell level, which are very useful for understanding physical phenomena, are still complex to exploit and synthesize in tools that can be used at prototype scale. These pseudo-properties are often expressed as a function of the properties of the base material, on the one hand, and the relative density of the metal foam, on the other.

Finally, the potential uses of these new materials naturally dictated the focus of our studies on the properties of metallic foams.

This article therefore proposes a structured approach by application, for the main current fields of use for metallic foams (crash, ballistic, heat exchange, medical).

The relationships between the composition and morphology of metal foams and the resulting properties are presented for each area, along with the corresponding key characteristics.