Design and Mechanical Properties Analysis of Structures with Shape Memory Negative Poisson’s Ratio

Using shape memory polymer as matrix material to prepare negative Poisson’s ratio structure, the shape memory performance, impact resistance, light weight and other characteristics are integrated, which has great application prospects in vehicle collision, aerospace, military, medicine and other fields. PLA, TPU, and PETG materials were selected for shape memory performance test, and the shape recovery rate, shape recovery time and shape fixation rate were analyzed to show that the shape memory performance of PLA materials was better. The quasi-static compression test and simulation analysis were carried out for four typical negative Poisson’s ratio structures with PLA as the base material: concave hexagon, concave triangle, star and rotating cell. Through the analysis of Poisson’s ratio effect, impact resistance and energy absorption ability, the mechanical properties of the concave hexagonal structure are better, and the negative Poisson’s ratio effect is obvious. When the compressive strain is less than 15%, the rebound rate of other structures is above 90% except star structure. The response surface optimization method is used to optimize the impact response of the concave hexagonal structure with the maximum residual displacement after impact deformation. After optimization, the maximum displacement under energy impact deformation is reduced by 21.76% and the energy absorption is increased by 3.29%, and the optimized structure has better shape recovery performance, which provides a reference for designing the buffer structure with self-recovery performance.