About 3D Printing

3D Printing is an additive manufacturing process that creates a physical object from a digital design. The process works by laying down thin layers of material and then fusing the layers together to form a three-dimensional object.
Not every part is suitable for 3D Printing. We can analyse and assess every part that qualifies for AM production and advise you on the most suitable technology. If you have an application you would like us to look at, please feel free to get in contact.

An overview of 3D printing technologies

Powder Bed Fusion – PBF

The Powder Bed Fusion process encompasses Direct metal laser sintering (DMLS), Electron beam melting (EBM), Selective heat sintering (SHS), Selective laser melting (SLM) and Selective laser sintering (SLS).

All PBF processes involve the spreading of the powder material over previous layers. There are different mechanisms to enable this, including a roller or a blade. A hopper or a reservoir below of aside the bed provides fresh material supply. Direct metal laser sintering (DMLS) is the same as SLS, but with the use of metals and not plastics. The process sinters the powder, layer by layer. Selective Heat Sintering differs from other processes by way of using a heated thermal print head to fuse powder material together. As before, layers are added with a roller in between fusion of layers. A platform lowers the model accordingly.

Powder bed fusion (PBF) methods use either a laser or electron beam to melt and fuse material powder together. Electron beam melting (EBM), methods require a vacuum but can be used with metals and alloys in the creation of functional parts.

Direct Energy Deposition – DED

Selective Laser Sintering (SLS) is a commonly used powder-based additive technology to create models, prototypes and end-use parts in durable, engineering-grade thermoplastics.

Directed Energy Deposition (DED) is a 3D printing method which uses a focused energy source, such a Electron Beam, Laser or Arc (PAW, GTAW, TIG), to melt material in powder or wire form which is simultaneously deposited by a nozzle. As with other additive manufacturing processes, DED systems can be used to add material to existing components, for repairs, or occasionally to build new parts.

DED allows near net shape production of relatively large parts with minimal tooling.

Multi Jet Fusion – MJF

Multi Jet Fusion technology builds parts by laying down a thin layer of powder on a print bed over and over before an inkjet array in the print carriage sweeps over the print bed, jetting two agents down. One being a fusing agent and the other a detailing agent that is used to reduce fusing near the contours of the part to achieve greater detail.

Material extrusion – FDM

Material Extrusion 3D printing technology uses a continuous filament of a thermoplastic material as a base material. The filament is fed from a coil, through a moving heated printer extruder head, often abbreviated as an extruder. The molten material is forced out of the extruder’s nozzle and is deposited first onto a 3D printing platform, which can be heated for extra adhesion.

A wide variety of materials can be extruded, the most popular being thermoplastics, such as Acrylonitrile Butadiene Styrene (ABS), PolyLactic Acid (PLA), High-Impact Polystyrene (HIPS), Thermoplastic PolyUrethane (TPU), aliphatic PolyAmides (PA, also known as Nylon), and more recently high performance plastics such as PolyEther Ether Ketone PEEK or PolyEtherimide PEI. If you are interested in printing in high- temperature plastics, please don’t hesitate to contact a member of Aurora’s team.

Binder Jetting

Binder Jetting is an additive manufacturing process in which an industrial printhead selectively deposits a liquid binding agent onto a thin layer of powder particles — either metal, sand, ceramics, or composites — to build high-value and one-of-a-kind parts and tooling. The process is repeated layer by layer, using a map from a digital design file, until the object is complete. Binder Jetting has the advantage of high speeds and material flexibility but the disadvantage of needing a furnace to remove the binding agent.

Stereolithography  – SLA

Stereolithography (SLA), or resin 3D printing, is widely used for its ability to produce highly accurate prototypes and parts in a range materials. Stereolithography belongs to a family of AM technologies known as vat photopolymerization, otherwise known as resin 3D printing. These machines are all built around the same principle which uses a light source—a laser or projector—to cure liquid resin into hardened plastic. The main difference between the various technologies surrounds the arrangement of the main components like the resin tank or light source.

Selective Laser Sintering – SLS

Selective Laser Sintering (SLS) is a commonly used powder-based additive technology to create models, prototypes and end-use parts in durable, engineering-grade thermoplastics.

SLS uses a recoater to spread a thin layer of powder over the build volume. A laser sinters the cross-section of the part to fuse the powder together. The z axis then drops one layer and the process begins again until the build is finished. Parts are then excavated from the build powder-cake so excess powder can be removed. The unused powder in the build envelope acts as the support structures which eliminates the need to remove support structures after the build process. This process has considerable advantages over FDM as there is often very little redesign required.

Cold Spray

Cold spray is an additive manufacturing technique that deposits powder particles in the solid state by accelerating them towards a surface within a supersonic gas flow. Cold spray can be used to coat a variety of materials (metals, glass, ceramics, polymers). This technology is widely used for repair of worn or damaged metal components and is mainly focused on the build of large components.