General principle of selective laser melting of metal powder beds
Selective laser melting of metallic powder bed

This process involves selectively melting particles in a powder bed in a neutral gas chamber using a laser beam that scans the surface and simply melts the powder on a section determined by the STL file. After the layer has solidified, the build platform is lowered so that a new layer of powder of a predetermined thickness can be spread. The laser scans the surface of the powder again to create an additional section superimposed on the previous layer (figures 1 and 2 ). The 3D part is, in a way, a stack of flat 2D layers.