Numerical and experimental crushing behaviour investigation of EBM printed auxetic chiral lattices

Abstract

In this study, Electron Beam Melting (EBM) is used to produce chiral auxetic lattices, and the compression of chiral auxetic lattice is investigated experimentally and numerically in the edgewise direction, where auxeticity can be experienced. Titanium Alloy (Ti6Al4V) metal- lic powder is used in this study. To understand mechanical behaviour and to characterize EBM printed parts, tensile tests are conducted. According to the tensile test results, a constitutive equation is selected, calibrated and adopted to represent the behaviour of the material. Further- more, a chiral unit cell is manufactured and tested with a compressive load profile to investigate its displacement limit by applying large displacements without experiencing permanent defor- mations, degradation or failures. The same scenarios explored in the experiments are then analyzed by means of non-linear computational models using a commercial finite element code to validate a numerical approach for optimal design and performance prediction.