What is Additive Manufacturing?


Additive manufacturing (AM), also known as “3D printing”, is a relatively new and advanced form of production that is growing in importance. The process begins with taking computer aided design (CAD) files and translating them into physical 3D objects. Beginning as a rapid prototyping technology, 3D printing is now used for more complex applications, such as the fabrication of tooling and even the on-demand production of end parts.

Additive manufacturing processes are nearly as diverse as more traditional manufacturing technologies, like subtractive manufacturing or injection molding, but are broken up into about seven broad categories. These include:

  • Material extrusion: some feedstock, usually filament made from thermoplastic or composites, is fed into a deposition head, usually a heated extruder, extruding layers of material onto a substrate. This process is often referred to as “fused deposition modeling”, or “FDM”.
  • Powder bed fusion: An energy source, usually a laser or electron beam, is directed at a bed of polymer or metal powder, fusing the particles together in thin layers to create plastic or metal parts. In the case of thermoplastic, this AM process is usually referred to as “selective laser sintering”, or SLS. For metal and metal alloys, it is called “direct metal laser sintering”, or DMLS, if a laser is used and, “electron beam melting”, or “EBM”, if an electron beam is used.
  • Binder jetting: An inkjet printhead deposits liquid binder across a layer of powder, which may then undergo post-processing to create a final part.
  • Inkjet 3D printing: A photopolymer ink is jetted onto a substrate before an ultraviolet light is used to cure the resin layer by layer.
  • Vat photopolymerization: An energy source, such as a laser or digital projector, casts ultraviolet light onto a photopolymer resin, curing it. In the case that a laser is used, it is referred to as stereolithography (SLA). When a projector is used, it is called digital light processing (DLP).
  • Directed energy deposition (DED): This is a form of metal 3D printing in which a metal, such as stainless steel, is introduced, in the form of a powder or wire, directly to an energy source, such as a laser or electron beam, melting it layer by layer.
  • Laminated object manufacturing (LOM): The least common form of 3D printing, this process involves fused together sheets of material and then performing subtractive manufacturing on the layers, essentially cutting out the desired geometry.

Already deployed in a variety of industries, from aerospace and automotive to healthcare, additive manufacturing has a number of advantages over traditional manufacturing. It’s possible to achieve additional functionality and the optimization of mechanical properties through the creation of complex geometries that would not be achievable with other forms of production. The additive nature of the process enables unprecedented design freedom. The ability to produce parts on-demand means limiting an unnecessary stock of goods and cutting lead time tremendously.

It’s worth noting that all additive manufacturing technologies require some form of post-processing, which can mean significant additional labor, depending on the printing process. Moreover, most additive manufacturing processes require deep materials science expertise.

Though every household may not own 3D printers in the near future, many manufacturing businesses surely will own 3D printers. You will be able to find case studies throughout this website. It is widely believed that, if additive manufacturing reaches high levels of adoption, it can have a tremendous impact on the global supply chain.