Similarities of the Mechanical Responses of Body-Centered Cubic Lattice Structures with Different Constituent Materials Under Compression

This study investigates the compression behaviors of body-centered cubic (BCC) lattice structures with three different constituent materials, i.e., polylactic acid (PLA), AlSi10Mg and polyamide 12 (PA12), fabricated by fused deposition modeling (FDM), selective laser melting (SLM) and multi-jet fusion (MJF) techniques, respectively. The numerical models of finite element analysis (FEA) with beam elements and isotropic hardening material constitutive law are built to simulate different BCC lattice structures. The equivalent elastic modulus and energy absorption properties are obtained from the FEA simulations and the quasi-static compression tests. The results from the theoretical modeling, numerical simulations and experiments match well with each other. It is interesting to show that although the three constituent materials have distinct mechanical properties, the architected lattice structures exhibit nearly the same deformation mode and similar stress-strain curve characteristics. Specifically, all the lattices exhibit typical type-I stress-strain response with very close densification strain around 0.7, although the constitutive materials have more than four times difference in ductility (0.25 for PA 12 and 0.06 for PLA). This similarity offers a feasible approach to investigate the mechanical responses of lattice structures by employing PLA and PA12 as constituent materials rather than expensive metals for reducing cost and ensuring universality of results.

Automated summary

This study investigates the compression behaviors of body-centered cubic (BCC) lattice structures with three different constituent materials and finds that despite the distinct mechanical properties of the materials, the lattice structures exhibit similar deformation modes and stress-strain curve characteristics, offering a feasible approach to reducing cost and ensuring result universality by employing cheaper materials like PLA and PA12.