Understanding Cylinder Temperature Effects in Laser Beam Melting of Polymers

Laser beam melting of polymers allows for the fabrication of highly complex parts with excellent properties. For part generation, temperatures close to the softening range of the polymer have to be set on the powder bed surface and in z-direction. These high temperatures are directly linked to high durations of the cooling phase, high delay times for part availability and progressing material aging. Within this work, the impact of the heat control in z-direction is analyzed. Therefore, the cylinder heater temperature is varied and the fabricated parts are characterized extensively. Thermal simulation of the temperature distribution within the build chamber is performed to predict the aging behavior of the material and the maximum cooling time. It could be shown that the majority of part properties is unaffected by reducing the cylinder temperature, whereas cooling time and material aging of the surrounding powder could be reduced. This indicates the possibility of a solidification-optimized processing strategy with targeted temperature control in z-direction.