3D printing is sometimes referred to as Additive Manufacturing (AM). In 3D printing, one creates a design of an object using software, and the 3D printer creates the object by adding layer upon layer of material until the shape of the object is formed. The object can be made using a number of printing materials, including plastics, powders, filaments and paper.
There are three main categories of 3D printing technologies:
- Extrusion (FFF and FDM): a plastic filament is melted and deposited on the build platform of the 3D printer to form the object layer by layer.
- Resin (SLA and DLP): a liquid photosensitive resin is cured by a laser or a projector to form the object directly in the resin tank of the 3D printer. The most common 3D printing technology using photopolymerization (solidification of the photosensitive resin via a source of light) is called stereolithography (SLA).
- Powder (SLS, SLM, DMLS…): a powdered material is sintered or melted by a laser, the grains of powder are bonded or melted together (sintered) to obtain a solid structure. The Selective Laser Sintering (SLS) technology is the most common among powder-based 3D printing technologies, although several derived processes exist.