Selective Laser Sintering (SLS) is an additive manufacturing process that builds objects by using a high-power laser to fuse fine polymer powder, layer by layer, into solid parts.
Selective Laser Sintering is a powder-based form of 📝3D Printing developed by Carl Deckard and Joe Beaman at the University of Texas in the mid-1980s. It is one of several powder bed fusion technologies and is used most often with nylon and other thermoplastic powders.
An SLS printer heats a reservoir of polymer powder to just below its melting point, then a recoating blade spreads a thin, even layer across the build platform. A high-power laser scans the cross-section of the model, sintering the particles so they fuse into a solid mass. The platform lowers, a fresh layer of powder is spread, and the cycle repeats until the part is complete.
Because the surrounding loose powder supports each layer, SLS requires no dedicated support structures, allowing complex geometries and interlocking assemblies. After printing, parts are excavated from the powder bed and cleaned with compressed air, and unused powder is recycled. SLS produces durable, functional parts, but its machines are generally more expensive than filament or resin printers.