Lightweighting of material is crucial for fuel efficiency in transportation applications such as aircraft, automobile, and others, as well as in the movement of commodities from one location to another. By strategically adding porosity, higher strength-to-weight and modulus-to-weight ratios have been attained. It has been shown that hybrid lattice-cored sandwiches may be made to meet increasingly demanding requirements of engineering . We utilize a foam filled cellular lattice design in sandwich core. Cellular lattices with struts have shown high promise in lightweighting. We utilize new open and closed cell architectures using a body centered cubic lattice with plates and struts to create open cell geometries infiltrated by foam. . Using the center point, the walls (plates or faces) were fabricated above and below the midpoint of the cube. A Formlabs base 3 SLM 3D printer was used with Tough Resin. Compression testing was conducted on the lattice and modulus, strength and energy were computed from the dimensions of the lattice, force and displacement extracted from the Shimadzu tensile testing machine. The effect of increasing plates with respect to modulus, strength and energy change is explored. The effect of density is incorporated through mapping the modulus and strength as a function of density using Maxwell relationships. The results indicate that non symmetric distribution of plates harnesses bending modes in the lattice that enhances modulus to weight and strength to weight performance in the lattice. The design system offers a new pathway to realizing multifunctional lightweight performance in sandwich design.
Regents ProfessorUniversity of North Texas