Microstructural characterization and mechanical properties of functionally graded PA12/HDPE parts by selective laser sintering

The use of selective laser sintering in the production of functional gradient materials offers advantages, as freeform construction and localized control of the composition and process parameters, compared to other rapid manufacturing processes. In this work, selective laser sintering was used for manufacturing three-dimensional parts in functionally graded polymer blends based on polyamide 12 and high-density polyethylene with gradient composition in two directions (Y and Z). Test specimens were prepared in PA12/HDPE ratios of 0/100, 20/80, 50/50, 80/20 and 100/0 (w/w). These specimens were assessed in terms of density, microstructure by scanning electron microscopy and polarized light microscopy and mechanical performance by DMA. The sintered binary blend systems with composition gradient showed microstructure and properties variation as function of the blend compositions. The results demonstrated the potential of selective laser sintering to manufacture advanced polymeric functional gradient material parts.