Experimental investigation of design parameters on geometrical accuracy of selective laser sintered parts

Abstract

Selective Laser Sintering (SLS) is becoming a popular choice for the fabrication of polymer parts of medium batch sizes. Understanding the effect of various factors influencing the geometrical accuracy of parts fabricated with selective laser sintering is key to ensuring consistent quality. This study attempts to evaluate the effects of different design parameters on a part-to-part variation in the geometrical accuracy of fabricated parts within the same build. A three-level Box-Behnken response surface methodology was adopted with the part orientation, part thickness, build position, and feature size as factors to investigate the impact on geometrical accuracy. A specimen comprising various through holes of different thicknesses was fabricated using SLS. The part-to-part variation in dimensional accuracy and circularity was inspected with a video measuring system to evaluate the effect of factors. The part orientation, part thickness, and build position impart a stronger influence on dimensional accuracy while the circularity was highly affected by the part orientation of the specimen. Further, the geometrical accuracy of the fabricated features was optimized separately with different sets of factors and validated experimentally.