Expanded polystyrene beads (aka styrofoam) are coated with a slurry of metal powder and a binder. The coated beads are heat-treated to evaporate both the styrofoam bead and the binder, leaving only fragile hollow metal powder shells. Further heating (sintering) causes the shells to solidify and also joins the shells where they touch. The process allows the production of lightweight cellular metals with a uniform and reproducible cell structure, ensuring consistent mechanical and physical properties; this is difficult to achieve with other manufacturing routes for cellular metals.
Cellular metals are used as crash absorbers in the automotive industry.
It is possible to create structures from any type of metal that can be sintered. The material can be customised by adjusting the size of the spheres and the shell thickness. The finished material can be cut, drilled, or welded like a solid material.
You get the samples seen on the picture. The piece measures minimum 3 cm x 3 cm x 3 cm. The samples are cut from larger pieces, so the spheres are cut through on some of the cube's surfaces.