Rapid Selective Laser Sintering Service
| AS9100D | ISO9001 | ISO14001 | IATF 16949
About Selective Laser Sintering
Selective Laser Sintering (SLS) is a powder-based 3D printing process that uses a laser device to fuse powder materials of plastic, glass, ceramic, and a range of different material powders by heating, rather than melting, to print a hardened three-dimensional object. The laser traces the pattern of each cross-section of a 3D design onto a bed of powder. After one layer is built, the build platform lowers, and another layer is built on top of the previous layer. This process continues until every layer is built and the part is complete.
It was one of the first additive manufacturing (AM) techniques developed in the mid-1980s. All selective laser sintering 3D printers are built around similar processes. The main differentiators are the type of laser, the size of the build volume, and the complexity of the system. Different machines use different solutions for temperature control, powder dispensing, and layer deposition.
Advantages of Selective Laser Sintering
SLS 3D printing has been a popular choice for engineers and manufacturers for decades. Low cost per part, high productivity, and established materials make the technology ideal for a range of applications from rapid prototyping to small-batch, bridge, or custom manufacturing.
It is used to print any complex designs, functional parts, living hinges, and interlocking parts. It is popularly used for creating rapid prototypes and for final production. Industries that need high-quality parts in a small quantity, such as aeroplane parts, hearing aids, prosthetics, and dental retainers, usually prefer this process.
- It is very good for prototypes that require strength.
- It consists of the functional plastic part, which contains mechanical properties and is used in prototyping or low volume production.
- It is a self-supporting additive manufacturing technology. Because the product lies in a bed of powder as it builds, no supplementary support structures are required, making SLS capable of producing geometries that no other technology can.
Design Freedom
It does not require support structures because unsintered powder surrounds the parts during printing. SLS printing can produce previously impossible complex geometries, such as interlocking or moving parts, parts with interior components or channels, and other highly complex designs.
High Productivity
SLS printing is the fastest additive manufacturing technology for functional, durable prototypes and end-use parts. The lasers that fuse the powder have a much faster scanning speed and are more accurate than the layer deposition methods used in other processes.
Proven, End-Use Materials
The key to SLS 3D printing’s functionality and versatility is the materials. Nylon and its composites are proven high-quality thermoplastics. Laser-sintered nylon parts have close to 100% density with mechanical properties comparable to parts created with conventional manufacturing methods like injection molding.
Material options
Moxperts offer a wide variety of certified alloys for rapid selective laser sintering services. If the material is not listed, feel free to contact us for a customized solution.
The most common material for SLS is Polyamide 12 (PA 12), also known as Nylon 12, a highly capable engineering thermoplastic for both functional prototyping and end-use production. Nylon is ideal for complex assemblies and durable parts with high environmental stability.
Polyamide powder can be filled with various additives (such as carbon fibers, glass fibers or aluminum) to improve the mechanical and thermal behavior of the produced SLS part. Materials filled with additives are usually more brittle and can have highly anisotropic behavior.
Polyamide 12 (PA 12)
Polyamide 11 (PA 11)
TPU-88A
Aluminium-filled nylon (Alumide)
Glass-filled nylon (PA-GF)
Carbon-fiber filled nylon (PA-FR)
Prototype
Finishing Services
This is the default finish for SLS parts. After the SLS printing process is finished, all powder is removed from the part with compressed air. The surface is cleaned via plastic bead blasting to remove any un-sintered powder sticking to the surface. This finish is inherently rough, similar to medium grit sandpaper (satin-like matte finish that is slightly grainy). This is also the best surface preparation for painting or lacquering. Internal holes may be drilled upon request.
For a smoother surface texture, Nylon SLS parts can be polished in media tumblers or vibro machines. A tumbler that contains small ceramic chips that vibrate against the object gradually erodes the outer surface down to a polished finish.
The fastest, most cost-effective method to color SLS prints is via a dye process. The porosity of SLS parts makes them ideal for dyeing. The part is immersed in a hot color bath with a large range of colors available. Using a color bath ensures full coverage of all internal and external surfaces. Contact Moxperts for specific color options for the prototypes.
SLS parts are able to be spray painted. SLS parts can also be coated with lacquer (varnish or clear coat). Via lacquering, it is possible to obtain various finishes, such as high gloss or a metallic sheen.
A correctly sintered SLS part will have some inherent water resistance. Coatings can be applied to further enhance this. Silicones and vinyl-acrylates have been shown to provide the best results. Polyurethane (PU) is not recommended for waterproofing SLS parts. If complete water resistance is required, a dip coating method is recommended.
SLS parts are able to be electroplated. Stainless steel, copper, nickel (or a combination of both), gold and chrome can be deposited on the surface of parts to increase strength or electrical conductivity in shielding applications. Parts are cleaned, and a conductive layer of material is applied to the surface.
Contact Moxperts for more customization options for your prototyping project.
