Porous materials featuring cellular structures are known to have many interesting combinations of physical and mechanical properties. Some of them have been extensively used in the transportation field (i.e. balsa wood). Steel foams presented promising theoretical properties for both functional and structural applications in transportation, but processing of such a kind of foams is complex due to their high melting point. Recently a technique for processing Cu-based alloys open-cell foams through the molten metal infiltration of a leachable bed of amorphous SiO2 particles was proposed. A variation of the proposed technique that uses SiC particles as space holder is now presented and was recently successfully applied for dual phase steel foam processing. Results from a processing of dual phase DP500 steel foams, including some morphological, micro-structural and mechanical characterization, are here presented.

An experimental study on solidification structure development and on endogenous inclusion precipitation in a continuously cast resulphurised steel is presented. Results were obtained by investigating two heats of a free cutting C-Mn steel cast in billets with a diameter of 145 mm. The as cast structure was evaluated by macro- and microscopic analyses. Primary and secondary dendrite arm spacing measurement allowed to estimate the solidification time experienced by the steel in different region of the billet section. Modification of the pearlite vs. ferrite fraction was also studied as a function of distance from billet surface and thus with reference to solidification conditions. Endogenous inclusions of the type MnS and CaO-Al2O3 were analysed. Their formation was discussed as a function of the composition of the heats. Also for the inclusions resulting after steel solidification, the data suggested that the effects of local solidification condition and of segregation played a role of primary importance.