Abstract:
Based on the static three-point bending and dynamic three-point bending experiments, the influence of the inclined angle of the conch shell element on the fracture behavior of the specimen under different strain rates was studied. Four groups of samples were prepared by 3D printing using two kinds of matrix materials, soft phase and hard phase. Based on quasi-static and dynamic three-point bending impact experiments, the load-displacement curves and initiation work of four groups of samples were obtained. The results show that the structure has different crack deflection paths under different strain rates. At lower strain rates, the 45° sample has higher strength, better energy absorption effect and better fracture toughness; At higher strain rate, the strength and toughness of 45° samples are better. Finally, through the drop weight experiment, the influence of different impact speeds on the failure of the mixed design structural plate was studied, and the critical failure speed and two failure modes were obtained. The drop weight experiment shows that when the impact velocity reaches 1.8 m/s, further increasing the impact velocity to 2.0 m/s has no obvious effect on the dynamic response of the structure. The proportion of the energy absorbed before the crack initiation and the energy absorbed after the crack initiation in the total energy absorption tends to be stable.