In situ compression and mechanical characterization of nature-inspired meta-grain lattices

Additive Manufacturing (AM) lattices exhibit high stiffness/strength-to-weight and specific energy absorption, providing great benefits to the transport and biomedical industries. Meta-grains - a topological feature inspired by Bravis lattices that can improve mechanical performance of lattices [1]. We are currently investigating the introduction of twinned meta-grains to Body-Centred Cubic (BCC) and Face-Centred Cubic (FCC) lattices AMed in Inconel 718. Our preliminary results show that twinning induces improvement in lattices’ mechanical properties. However, the underlying strengthening/fracture mechanisms and the role of AM defects for twinned lattices which have not been observed or quantified in 3D. We propose to perform in situ compression testing with X-ray Computed Tomography at BM18. We will quantify the local strain through Digital Volume Correlation and defects in the AM lattices to better understand their failure behaviour and design future lattice architecture.