Direct metal laser sintering (using metal powders), also known as DMLS, is a rapid prototyping technique of direct construction of prototypes obtained from 3D files.
With this technique, prototypes are built directly from the chosen metal powder by selective addition (parts can be made from cast Aluminum, Steel, Stainless Steel, Titanium, etc.).
The powdered material is processed locally by a high-energy laser, which fuses the grains into solid 3-D shapes, thus giving rise to the metallic prototypes.
The metal powder sintering technique realizes parts with really high details by going so far as to create walls as thin as 0.9mm and geometries very close to the machined measurements (near net shape).
The high temperature reached in the area where the laser melts the metal generates induced surface stresses during subsequent cooling of the metal-sintered parts. Therefore, supports that stabilize 3D solid constructions of more complex prototypes may be needed to prevent deformation.
This technique is very suitable for making objects that are definitely very complex or impossible to achieve by more basic techniques. Thus, the favored objects are all those parts with high shape complexity and low mass.