The world of 3D Printing is constantly developing solutions to widen the application scope of this production method along all fields. New materials open the doors to new solutions, different structures for diverse application, and the demands of the market lead to the development of reliable processes to fit its needs. Which are these processes? And which technologies are currently most adopted for industrial application?
SLS (Selective Laser Sintering)
Selective Laser Sintering is one of the most utilized technologies for industrial 3D Printing for its high quality results, and for the wide variety of materials available enabling several use cases across industries.
This technology sinters with the heat of a laser the adjacent particles of powdered material to form a 3d model layer after layer.
Photo Source: 3YOURMIND
After a layer is sintered, the bed level slightly drops enabling a new layer of fresh powder fill the bed to start the next layer. This process iterates until the 3D object is finished.
One of the advantages of this technology, is that no support structures are required due to the constant contact of the printed object with the unsintered powder. Once the production is concluded, the rests of the material is removed from the model with compressed air in a sealed container.
Printing Powder Materials: PA, PAGF, TPU, ALUMIDE, Steel Alloys (though an additional sintering post-production process is needed), PACF, Carbon.
SLM (Selective Laser Melting):
As on the SLS process, here also the powdered material is consistently spread onto a plane surface where the particles are melted together with the application of a laser light.
Photo source: SpaceX
The primary difference compared to SLS lays on the fact that both, the heat and the precision of the laser make the powdered material particles melt completely. And during the cooling process they fuse back together creating one final solid structure. Support structures are used in this technology to reinforce the overhanging parts of the model as the melted material turns heavier to be hold by the remaining powder.
Powder Materials: Aluminum, Titanium, Stainless Steel, Cobalt Chrome
SLS and SLM technologies are especially suitable for either detailed or small models, with complex geometries or complicated inner structure such as voids, networks, special grids, among other.
DMLS (Direct Metal Laser Sintering)
Image Source: EOS GmbH
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In principle, this process belongs to the family of SLM technology, but is specifically used for metals, sintering the metal powder particles and producing a higher level of porosity in the parts. While SLM directly melts the particles creating a solid object of mono material or single component metals such as aluminum, DMLS is usually utilized for alloys.
In addition, DMLS does not require support structures as the printed object is continuously bounded by metal powder.
Powder Materials: Stainless Steel, Maraging Steel, Cobalt Chromium, Aluminum AlSi10Mg, Titanium Ti6Al4V
FDM (Fused Deposition Modeling) or FFF (Fused Filament Fabrication)
This technology is widely used due to its flexibility and its low initial investment cost, specially concerning equipment and materials. It works by depositing a melted material filament, usually a thermoplastics, through a heated nozzle, beginning with the transference of the 3D data into machine commands. The model is oriented on the machine platform from where the model is printed.
Photo source: Sculpteo
The way the model is built is by depositing small amounts of melted material along the horizontal plane. When each layer is completed, the machine rises the appropriate distance in the Z direction and begins with the following layer. Building material is supplied to the heated nozzle through a feeding mechanism and stabilizes directly after the extrusion.
Filament Materials: PLA, ABS, PC, PA, CopperFill, BrassFill, BronzeFill, WoodFill, Flexible (TPE, TPU), special filaments (transparent, fluorescent, conductive).
Note: The names of technologies and 3D print materials often vary, depending on the supplier.