Influence of Mixed Powder Aging on the Structural, Chemical, and Crystalline Morphological Properties of the PA12 Powder Used to Manufacture Selective Laser Sintering (SLS)

This study investigated the effects of multiple selective laser sintering (SLS) cycles on a polyamide 12 powder blend comprising 70% recycled and 30% virgin material. Thermal analysis revealed significant changes in the thermal behavior of the powder, including an increase in the melting temperature and crystallinity and a decrease in the crystallization temperature. Particle size distribution analysis revealed statistically significant differences between the initial and post sintering powder states. Microscopic observations revealed a strong correlation between the crystal and particle morphologies. These findings provide crucial insights into the microstructural evolution and thermal behavior of recycled PA12 powder during repeated SLS processing, aiding in the development of sustainable and ef-ficient powder recycling strategies for additive manufacturing.