Since the mid-1980s, Selective Laser Sintering has been utilized as a prominent additive manufacturing technology to meet the needs associated with obtaining 3D parts. However, as the search for faster printed parts with higher resolution increased, an alternative cost-efficient process was desired to meet such demands. With all in mind, Behrokh Khoshnevis invented the Selective Inhibition Sintering process for plastics.
HOW IT WORKS
- It starts by laying a thin layer of powder slightly above the previous layer, by sweeping a roller over both a powder supply tank and the build tank.
- Then, the areas of the powder bed selected for sintering inhibition are wetted by a printer.
- A radiation-minimizing frame is positioned to prevent areas of the powder layer which lie outside the part envelope from sintering.
- The entire layer is then sintered with a blast of thermal radiation from an infrared heater.
In the end, a solid polymeric block remains that is totally sintered except for those areas wetted by the inhibitor liquid.
- As implemented on the alpha machine, the heater is a coiled nichrome wire that is mounted on a carriage. This allows the heating element to be passed over the surface of the powder bed. Steps A-D are repeated until the part is completed.
- The ﬁnal part can be easily extracted from the surrounding material.