Materials & Design (Jan 2021)
Compression performance and mechanism of superimposed sine-wave structures fabricated by selective laser melting
Abstract
A novel superimposed sine-wave (SSW) structure was designed and fabricated by selective laser melting (SLM) in this work. The energy absorption performance, deformation modes, and fracture mechanism of heat-treated SSW components under compression were studied. The formability was analyzed and the results showed that the SLM fabricated SSW components possessed nearly dense microstructure and smooth surface morphology. The numerical simulation model was established to show the stress distribution and deformation mechanism during compression, and the fracture morphologies of SSW components were investigated. Experimental results indicated that the SSW components exhibited a maximum crush force efficiency (CFE) of 73.06%, which was higher than most reported energy absorption structures. As the height of sinusoid 1 (H1) increased, the energy absorption (EA) and specific energy absorption (SEA) gradually increased to 37.73 J and 8.45 J/g, respectively. Simulation results revealed that the secondary trough had a large deformation during the compression process, which greatly enhanced the load uniformity of the structure. Fracture mode of SSW components was ductile fracture due to the post heat treatment. The SSW structures had the potential to be used in aerospace, protective armor, and automotive industries.