Selective Laser Melting

A collimated infrared laser beam is deflected by a 2-axis scanning unit into the main chamber. The laser beam is focused onto a 12 × 12 mm² build stage that can be translated vertically with a travel range of 12 mm and sub-micron step size. The build stage can be heated using a silicon-nitride resistive heater. Powder recoating is based on a hopper feeding system. The powder reservoir can be moved across the baseplate with the aid of a motor-spindle assembly. The device is completely closed, preventing laser light or particles to escape. The chamber is continuously flushed with high purity argon gas. With the aid of manual flowmeters, a slight overpressure is created in the chamber to avoid oxygen contamination by the outside atmosphere. The whole setup (laser, scanning unit and printing chamber) is cooled down with a closed-loop air-water exchange based chiller.  The video below describes the basic principle behind  operando X-ray diffraction during SLM.