Electrical conductivity of hexagonal periodic lattice structures

Abstract

Periodic lattice structures are three-dimensional arrays of unit cells having carefully engineered geometric properties. Solid Freeform Fabrication (SFF) processes have made it possible to tailor structural, thermal, or electrical properties by varying the shape and density of the unit-cell geometry. In this paper, the electrical conductivity of a hexagonal lattice structure is analytically derived using an effective unit-cell approach. The relationship between ligament length, ligament radius, relative density and electrical conductivity has been derived. The analysis indicates that the electrical conductivity increases with relative density and is linearly dependent on relative density at low lattice densities. Conductivity measurements of Ti-6Al-4V hexagonal lattices made via the Electron Beam Melting (EBM) process over a range of relative densities from 4% to 16% were taken in order to experimentally validate the analytical models.