Effect of thermal post-processing on the mechanical properties and drilling performance of SLS-manufactured PA12 parts

OpenAlex İngilizce

This study examines the effect of post-thermal treatments on the drilling performance of Polyamide 12 (PA12) parts manufactured via Selective Laser Sintering (SLS). Samples underwent three treatments: as-built (untreated), cryogenic treatment and heating at 45 °C. Drilling was performed at various spindle speeds and feed rates to optimize hole quality. Hole analysis was conducted using stereo microscopy and image processing to assess delamination, while hole diameter and surface roughness were measured using a CMM and profilometer, respectively. Chip formation was also examined. Results show that hole diameter decreases at low feed rates, while at high feed rates, it shrinks or expands depending on spindle speed. Post-thermal treatments significantly reduced delamination but had minimal impact on hole diameter and surface roughness. Drilling parameters played a crucial role, with higher feed rates and lower spindle speeds producing shorter, uniform chips and smoother surfaces, while lower feed rates and higher spindle speeds increased chip jamming and surface roughness. This study highlights the significant influence of spindle speed and feed rate on hole quality in PA12 parts and provides valuable insights for optimizing drilling conditions in SLS-manufactured components.