SLS technology uses a laser to harden and bond small grains of plastic, ceramic, glass, metal (we talk in a different article about direct metal sintering), or other materials into layers in a 3D dimensional structure. The laser traces the pattern of each cross section of the 3D design onto a bed of powder. After one layer is built, the bed lowers and another layer is built on top of the existing layers. The bed then continues to lower until every layer is built and the part is complete.
One of the major benefits of SLS is that it doesn’t require the support structures that many other AM technologies use to prevent the design from collapsing during production. Since the product lies in a bed of powder, no supports are necessary. This characteristic alone, while also conserving materials, means that SLS is capable of producing geometries that no other technology can. In addition, we don’t have to worry about damaging the part while removing supports and we can build complex interior components and complete parts. As a result, we can save time on assembly. As with other AM technologies, there’s no need to account for the problem of tool clearance—and thus the need for joints—that subtractive methods often encounter. So we can make previously impossible geometries, cut down on assembly time and alleviate weak joints.
SLS really shines when you need plastic parts that will last. SLS is capable of producing highly durable parts for real-world testing and mold making, while other additive manufacturing methods may become brittle over time. Because SLS parts are so robust, they rival those produced in traditional manufacturing methods like injection molding and are already used in a variety of end-use applications, like automotive and aerospace.