Stiff Lattices with Zero Thermal Expansion and Enhanced Stiffness via Rib Cross Section Optimization
نویسندگان
چکیده
Honeycombs with thermal expansion coefficients equal to zero are described analytically. The two dimensional lattice microstructure designs described are made of positive expansion materials. This work builds upon previous results, and provides further analysis into creating an optimal rib cross section. The design of ribs with Tee shaped and I shaped cross sections is developed. The behavior of these lattices is compared with that of triangular and hexagonal honeycombs as well as prior rectangular lattice results in a modulus-density map. Lattice relative stiffness is improved by as much as a factor of 2.4 when compared with a curved triangular lattice with ribs of rectangular section. Thermal shear stress at the material interface is found to be small. These lattices do not undergo thermal buckling, in contrast to designs based on sublattices.
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