Fused Filament Fabrication

Fused filament fabrication is a 3D printing process that uses a continuous filament of a thermoplastic material. This is fed from a large coil, through a moving, heated printer extruder head. Molten material is forced out of the print head's nozzle and is deposited on the growing workpiece. The head is moved, under computer control, to define the printed shape. Usually the head moves in layers, moving in two dimensions to deposit one horizontal plane at a time, before moving slightly upwards to begin a new slice. The speed of the extruder head may also be controlled, to stop and start deposition and form an interrupted plane without stringing or dribbling between sections.

Fused filament printing is now the most popular process (by number of machines) for hobbyist-grade 3D printing. As other techniques, such a photpolymerisation and powder sintering, may offer better results at greater cost, they still dominate commercial printing.

The 3D printer head or 3D printer extruder is a part in material extrusion-type printing responsible for raw material melting and forming it into a continuous profile. A wide variety of materials are extruded, including thermoplastics such as acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), high-impact polystyrene (HIPS), thermoplastic polyurethane (TPU), aliphatic polyamides (nylon), and recently also PEEK. Paste-like materials such as ceramics and chocolate can be extruded using the fused filament process and a paste extruder.

Additive manufacturing (AM), also referred to as 3D printing, involves manufacturing a part by depositing material layer by-layer. There is a wide array of different AM technologies that can make a part layer-by-layer including material extrusion, binder jetting, material jetting and directed energy deposition.

These process have varied types of extuders and extrude different materials to achieve the final product using layer by layer addition of material approach. The 3D Printer Liquefier is the component predominantly used in Material extrusion type printing.

Extrusion in 3-D printing using material extrusion involves a cold end and a hot end.

The cold end is part of an extruder system that pulls and feed the material from the spool, and pushes it towards the hot end. The cold end is mostly gear- or roller-based supplying torque to the material and controlling the feed rate by means of a stepper motor. By this means the process rate is controlled.

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