Microstructural and mechanical properties study of various lattice structures of SS316L-CNTs nano composites fabricated through additive manufacturing

In this work, various lattice structures, such as face-centered (FCC), body-centered (BCC), gyroid (GD), and bare gyroid (BGD (without CNTs)) with four different porosities (60%, 70%, 80%, and 90%), were prepared through the selective laser melting additive manufacturing process. Stainless steel 316 l alloy was utilized as the base material, while 0.2 wt.% functionalized carbon nanotubes (CNTs) were employed as reinforcement. The uniform dispersion of CNTs was analyzed using FESEM, TEM, and Raman spectroscopy. The results indicated that the plateau stress increases with the addition of CNTs, irrespective to the lattice structure. Also, in case of relative density the plateau stress increases with increasing the relative density. Similarly, the energy absorption also increases with the addition of CNTs regardless to the lattice structure. However, with increasing relative densities, energy absorption increases up to the 30% deformation regardless to the lattice structure and followed order was the BCC > FCC > GD > BGD.