Thermomechanical properties of strut-lattices

The quest for light and strong construction materials in transportation systems has inspired significant research interest in miniaturized strut-lattices. In such applications, it is possible for these structures to be subjected to extreme loading conditions involving both temperature and pressure. We evaluate the effective thermomechanical properties of periodic lattices using an energy-based homogenization method under the assumptions of small strut-level deformation. The effects of multi-phase strut constituents on the behavior of the overall lattice are assessed with the aid of various topologies. Some examples that highlight different ways in which one could engineer these materials to perform unique thermomechanical functions are presented. These examples include lattice structures with zero and negative effective thermal expansion coefficients. The role played by temperature on multi-axial yield modes is analyzed. Also investigated are the pressure-induced nodal forces in non-symmetrically joined struts within a pressurized lattice at non-ambient temperatures.