Behavior of Steel Foam Sandwich Members Cast with 3D Printed Sand Cores

This paper reports a study of steel foams, one with a single layer of spherical cells and another with two layers of cells, under compressive and flexural loading. The steel foam specimens were cut from large-size foam plates made by casting AISI 8630 steel into molds filled with spherical sand cores. A 2D unit cell model was proposed based on stress fields in solid media with circular cuts, and finite element analyses were conducted to explain the observed behavior. The results indicated that higher initial stiffness and increased flexural strength in steel foam specimens can be achieved compared to solid steel specimens. The tests also revealed that the behavior of these foam plates in bending may be reduced by fracture resulting from stress concentration of perforated faces in tension. It is thus recommended that the perforated faces should be placed in compression zones to take advantages of metal foams.