Mechanical properties of open-cell titanium foams with different cell geometries (truncated octahedron and rhombic dodecahedron cells) were examined through compressive tests. These foams were manufactured through the electron beam melting (EBM) process. The compressive behavior depends on the porosity, cell geometry and the cell orientation. Titanium foams with truncated octahedron cells showed high strength compared to those of rhombic dodecahedron cells. This is due to the short cell edges in truncated octahedron cells. In addition, the parallel and oblique cell edges against the compression direction are effective to increase the compressive strength. Macroscopic shear bands caused by ordered cell geometry were observed in some titanium foams.

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Porous materials possess light weight and excellent thermal insulation performance. For disordered porous structures, the number of seed points is an important design parameter which is closely related to the morphology and mean pore size of the structure. Based on the arrangement of points in three-dimensional space, seven kinds of structures were designed by spatial Voronoi tessellation in this paper. The effect of the number of seed points on effective thermal conductivity for Voronoi was studied. Numerical simulation was conducted to research the effects of structural porosity, filling material and structural orientation on the effective thermal conductivity and heat transfer characteristics. The results showed that the effective thermal conductivity is closely related to the porosity and the matrix material. Different number and arrangement of seed points make the structure have different anisotropic performance due to different thermal paths. In addition, required the least number of seed points was obtained for the designation of isotropic random Voronoi.

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