Structure–Property–Processing Relationships for Stainless Steel Foams Made by Mechanical Aeration of Powder Slurries

A simple process, based on the mechanical aeration of a powder slurry, followed by gel casting and sintering, has been used to produce 316L stainless steel metal foams. The foams have spherical pores, with a small size range, connected by windows, to create an interconnected, open cell structure. Despite the simplicity of the process, the foams have good and reproducible foam structures and compressive mechanical properties, although the ability to vary the pore size and density is limited. While foams of this type are more likely to be suited to applications where the connected nature of the porosity is exploited, they demonstrate mechanical properties on a par with foams and porous metals specifically suited to structural applications, where specific strength and energy absorption are paramount. Foams made in this way therefore demonstrate the multi‐functionality that is required of them if they are to be exploited and are thus exciting prospects for further development.