Dynamic strain aging in Inconel718 additively manufactured lattices

The aim of this work is to investigate the manifestations of dynamic strain aging (DSA) on the mechanical behavior of Inconel718 body centered cubic (BCC) and face centered cubic (FCC) strut-based lattices manufactured via laser powder bed fusion. With that goal, both lattices were tested uniaxially in compression at temperatures ranging from 25 to 600 °C at 1x10-3 s−1 and strain rate jump tests were carried out at the same temperatures between 1x10-5 and 5x10-2 s−1 in order to detect the occurrence of serrated flow and to analyze the strain rate sensitivity. It was found that DSA manifests at the metamaterial level within a range of testing conditions that is highly dependent on the lattice topology. In particular, DSA is comparatively more pronounced in the FCC architecture. This study emphasizes the importance of analyzing the incidence of DSA in additively manufactured lattice structures targeted for structural applications.