Impact behavior of triggered and non-triggered crash tubes with auxetic lattices

In this study, impact behavior of triggered and non-triggered tubes with and without auxetic filler is examined using numerical methods. Material properties of tubes made of aluminum alloy and auxetic lattices utilizing ABSplus plastics are determined using tensile tests. Finite element analyses are performed using LS-DYNA software at 5 m/s impact velocity. Two different trigger shapes are suggested and compared each other and discussed the advantages and disadvantages over non-triggered tubes. For these loading conditions, trigger mechanism provides lower peak forces and higher crash force efficiency (CFE), but lower specific energy absorption (SEA). In addition, the effects of using auxetic fillers in these triggered tubes are investigated in terms of crashworthiness characteristics.