Strain Rate and Temperature Dependence of Compressive Mechanical Properties of Al-Mg-Sc Alloy Lattice Structures

Lightweight Al-Mg-Sc alloy lattice structures were manufactured through laser powder bed fusion process. Unit cell structure of the lattice structure specimens is rhombic dodecahedron with different relative densities. Compression tests were carried out under different strain rate and temperature conditions. Al-Mg-Sc alloy lattice structures showed high compressive strength compared to Al-Si-Mg lattice structure. The plateau stress was proportional to 1.9 power of relative density at 300 K and 573 K. The plateau stress at 300 K showed the negative strain rate sensitivity exponent of −0.0114, which was caused by the dynamic strain aging effect. The Zener-Hollomon (Z) parameter suggested that different thermally activated kinetics at 300 K and 573 K. Experimental results indicate the potential of Al-Mg-Sc alloy lattice structure as energy absorbing applications.