Functionally graded sustainable lattice structures: Insights into material grading and lattice hybridization

•Functionally graded composite lattice structures were additively manufactured.•The Gyroid and Schwarz primitive lattice were hybridized.•The best mechanical properties were shown by PLA-G/WPLA-SP lattice.•The findings indicate scope of future research on composite lattice structures. This novel work presents the investigation of functionally graded lattice structures (FGLS) based on polylactic acid (PLA) and wood-reinforced PLA (WPLA) composite. The synergistic effect of a multi-material system and hybridization of two different primitive lattices (Gyroid and Schwarz primitive (SP)) on compressive strength, specific energy absorption (SEA) and stiffness was studied. The findings of the study revealed that the hybrid FGLS fabricated combining the Gyroid lattice of PLA and SP lattice of WPLA (PLA-G/WPLA-SP) exhibits the highest values of stiffness, SEA, and compressive strength.