Mechanical behavior of open-cell rhombic dodecahedron Ti-6Al-4V lattice structure

The compression behavior of Ti-6Al-4V lattice structure with a cell shape of rhombic dodecahedron, which was fabricated by electron beam melting, was investigated at different temperatures. A series of quasi-static compression tests were performed at ambient temperature, 200°C, 400°C and 600°C with a strain rate of 10^-3s^-1. Two groups of design configurations were adopted by changing the cell size and thickness of struts with the sample size maintained unchanged. The results revealed that their properties varied with different cell sizes and temperatures. Larger cell size leaded to lower modulus and strength of the lattice. Higher temperatures resulted in lower strengths, modulus, densification strains and plateau stresses. The energy absorption of lattice at high temperature was discussed, and the experimental data were compared with aluminum foams, titanium foams and stainless steel lattice. It demonstrated that the rhombic dodecahedron Ti-6Al-4V lattice structure could be applied as load-bearing components and energy absorber at high temperature.