Modified face-centred cubic lattice with enhanced mechanical properties

In this work, a new lattice (MFCCZ) was proposed by modifying based on the conventional face-centred cubic with vertical reinforcing struts (FCCZ) lattice with the prospect of forming more plastic hinges to enhance energy absorption. A combined experimental, numerical and analytical effort was devoted to systematically investigating the quasi-static crushing behaviour of the newly proposed MFCCZ lattice. The experimental specimens were fabricated via the Fused Deposition Modeling technique. Satisfactory agreements were achieved between the experimental, analytical and numerical results. The experimental results showed that the mechanical performance of MFCCZ exceeds that of the original FCCZ (by up to 52.5% and 24.3% increase in specific plateau stress and SEA respectively). The finite element model and analytical model were used to probe the mechanisms of the energy-absorbing enhancement. It was found that rotating the oblique struts within the FCCZ lattice would effectively enhance the energy-absorbing capacity partly due to the formation of additional plastic hinges on the horizontal struts, and partly due to greater rotation about the plastic hinge on the oblique struts. The proposed MFCCZ lattice exhibited outstanding performance in comparison to previous lattices fabricated via additive manufacturing, indicating its potential in lightweight load-bearing applications.