Additive Manufacturing Processes Material Extrusion

Material Extrusion is also known as Fused Deposition Modeling (FDM) or Fast Filament Fabrication (FFF).

With material extrusion a material is extruded through a nozzle onto a build platform. Usually this platform is then lowered and the next layer is extruded on top of the first.

 


In the case of a complex shape, one with significant overhangs for example, support material is also extruded. This sacrificial material is later removed by hot water, water jet or a solvent.  


Most Material Extrusion systems use a filament. This is a polymer wire usually stored on a spool.

FDM process map


The vast majority of 3D printers worldwide are Material Extrusion 3D Printers. Originally invented by Stratasys FDM technology is now used by over 500 different vendors worldwide. 

Compared to other 3D printing technologies FDM produces very strong and dimensionally accurate parts. The characteristics of these parts as well as their materials are comparatively easy to understand and characterise when compared to other 3D printing technologies. The materials used in FDM are also often more familiar to clients in the space. FDM 3D printers are also relatively inexpensive to develop and manufacture. The FDM market is also much more dynamic and open than other markets. There is a rapid development and evolution of open source technologies in the space when compared to other technologies. Virtually all OEMs are open as well, meaning that their printers can take material from any materials vendor in either the 1.75mm or 2.85mm diameter. This means that the materials market for FDM is much more dynamic than other 3D printing technologies. Many more materials are being developed for FDM 3D printing than other technologies. Increasingly in industrial manufacturing, automotive and machine building it is FDM that is the technology of choice for companies wanting to do production with 3D printing.


Advantages:


  • Many materials on offer
  • Relatively inexpensive
  • Strong, tough parts
  • High dimensional stability
  • Most open technology with the largest number of vendors of machines and materials.

Disadvantages:


  • Vat polymerization and powder bed fusion have finer details
  • Vat polymerization can produce smoother parts

Main uses:

  • Desktop 3D printers
  • Manufacturing end use parts


Additive Manufacturing can be used for a wide range of materials such as:


Polymers  

Composites

Metals

Ceramics

Composites


In filament there are a number of popular materials:


ABS

PLA

PC

PA

PP

PET


Besides Fused Deposition Modeling are:


Vat Polymerization

Powder Bed Fusion