Composites for high energy absorption
1) lattice structures building process by SLM, 2) temporary core building by SLA, 3) silicone mold fabrication, 4) silicone mold refinement, 5) vacuum casting of the polymer, 6) lattice filled with polymer release.
Composite samples made with internal 316L steel lattice with variouos cells shape and morphology and filling polymer. Compression tests are used to know mechanical properties and to estimate the energy absorption per unit volume. These information are used to design and produce the prototypes and final components.
The comparison of the hybrid samples compression curves with the curves obtained for the constituent materials (lattice structure and polymer) shows higher strength and stiffness.
As expected, the polymer filling causes the translation of the force-displacement curve towards higher values. However, the relative increase of the mechanical strength between the hybrid material and the sum of constituents is generally much higher than expected.
The most relevant property of polymer-filled composites is that the energy absorbed by the hybrid materials is much higher (up to 70%) than the sum of the energies absorbed by their constituent materials.
Increment of the strain energy of the hybrid materials with respect to the sum of energies associated with their constituents.