Inertial stabilization of flexible polymer micro-lattice materials

Soft micro-lattice materials with different lattice geometries were fabricated using a self-propagating photopolymer waveguide process. The parent polymer was characterized by dynamic mechanical analysis and the glass transition temperature shifted with equivalent strain rate. Quasi-static and dynamic compression tests were subsequently carried out to investigate the inertial stabilization of lattice member buckling as a function of strain rate and structural geometry (e.g. relative density and lattice aspect ratio). A high-speed digital camera was used to record the progression of deformation and failure events during compression. The micro-lattice structures exhibited super compressibility and increased strength. The observed strength increase, particularly for high aspect ratio and high strain rate, was attributed to inertial stabilization.