Effect of material variation on the uniaxial compression behavior of FDM manufactured polymeric TPMS lattice materials

Abstract

Triple periodic minimal surface (TPMS) based lattice materials are being explored for potential use in energy absorption and biomedical implant applications worldwide. In this study, the mechanical behavior of Schwarz-P TPMS lattice material under uniaxial compression has been compared for two different polymers – PLA and ABS, at different compression speeds from 5 mm/min to 35 mm/min to obtain a comprehensive picture. It was seen that while both material samples showed a layered manner of deformation wherein the stresses varied periodically, they behaved in slight contrast to each other when strain rates varied. The PLA samples showed 10% less compressibility than ABS samples, though both materials exhibited catastrophic failure tendency. The first peak stress increased linearly with the strain rate but the PLA samples show up to 30% higher value than ABS. The ABS samples had less variation between samples compressed at same deformation rate and inter-sample variation of the mechanical behavior was negligible at intermediate deformation rates. In the end, a cumulative picture has been shown where averaged mechanical behavior has been compared for both materials at different strain rates.