Architectured materials for space applications: a computational tool for the parametric optimization of a three-dimensional lattice subjected to stiffness constraints

F. ONGARO, K. MATHIS, F. MASSON, J. DIRRENBERGER
2019
Architectured materials, whose discrete configuration provides unique combinations of enhanced struc- tural properties at low weight, solved a variety of technical challenges in material science, architecture, aerodynamics and mechanical engineering. This peculiar characteristic, together with a high degree of de- sign freedom leading to the possibility to tailor their mechanical properties in each direction, makes them very promising in a vast number of industries including aerospace,
more » ... aerospace, automotive, marine and constructions. However, the use of architectured materials is conditional upon the development of appropriate consti- tutive models for revealing the complex relations between the parameters of the microstructure and the macroscopic behavior. Notwithstanding a great variety of analytical and numerical techniques have been proposed and discussed in recent years, explicit formulas for the effective mechanical properties are de- rived in a very small number of investigations. To provide a contribution in this limitedly explored research area, this paper describes the mathematical formulation and modelling technique leading to closed-form expressions for the effective stiffness of a three-dimensional lattice composed of identical hexatruss cells. The derived analytical relations, verified by performing experimental tests on a 3D-printed lattice, are then integrated into a parametric optimization problem for finding the optimal microstructures parameters that meet a given set of stiffness requirements. This strategy offers a less computationally way to solve optimization problems for architectured materials and, as a practical example, the specific case of the Spacecraft-Launcher Damping Interface is considered. The developed theory, however, is general enough to be easily applied to different types of structures in the aerospace industry.
doi:10.13009/eucass2019-167 fatcat:2lmwcjlijrbuzgc24yhek2wj6m