SLS is an additive manufacturing process that uses a laser-based technology. A computer guided laser beam selectively creates parts by sintering polymer powder particles to bind them together. During the 3D printing process, the SLS machine preheats the powder material that is in the printer bed to just below its melting point and then the laser further raises the temperature of the selected regions to melt and fuse the powder together.
First a roller will apply a layer of polymer powder on the build platform, then the laser will sinter the powder according to the 3D model. The printer's build platform will lower itself after a layer is completed and apply a new layer of powder. The process is repeated till the part is created. Once the 3D print is complete the object then needs to cool down before it can be taken out of the printer.
Where 3D printing processes such as FDM and SLA require support structures to build complex overhanging parts, SLS process does not need to create any supports as the parts are surrounded by unsintered powder at all times. This allows for more design freedom to create intricate geometries such as interlocking parts, moving parts, hinges etc.
SLS 3D Printing Is Ideal For
Prototyping with mechanical properties as compared to those of injection-moulded parts
Low Volume Production
Manufacturing prostheses or implants
Architectural models
Functional parts can be used for drones, robotics, special machinery, jewellery, sport equipment, footwear, orthopaedic technology, education or medical devices.
Personalized manufacturing of unique, complex, designs built as one-off products or in small batches
Technical Specifications For SLS
Standard Lead time: Minimum 4 working days depending on part size, number of components and finishing requirements lead time may increase.
Standard Accuracy: ± 0.1%
Layer thickness (resolution): 0.06 mm – 0.15 mm
Minimum Wall thickness: 1mm
Max dimensions: 380mm x 330mm x 450 mm. Large parts can be created by assembling individual parts by interlocking designs or gluing them together.
Surface finishing and Post Processing: Unfinished parts typically have a grainy surface but all kinds of finishes are possible. SLS parts can be sandblasted, smoothed, colored, painted and coated.
Materials Used In The Process
Nylon PA12 is a type of polymer powder that has great mechanical properties and chemical resistance. It is ideal for functional parts and prototypes.