泡沫增强复合材料点阵夹芯梁抗冲击性能

Dynamic Failure of Foam-Reinforce Composite Lattice Sandwich Beam to Local Impulsive Load

基于考虑分层失效和渐进损伤的三维Hashin失效准则,对复合材料点阵夹芯梁结构及其泡沫增强夹芯结构开展了局部冲击加载下的数值模拟分析,研究了冲击强度及泡沫增强效应对复合材料点阵夹芯梁结构抗冲击性能的影响。通过与实验的对比分析,验证了数值模型的有效性。结果显示,冲击强度的变化对结构的动态响应、失效模式及能量耗散形式都有明显的影响。泡沫增强效应使结构的横向变形响应速度降低,并且随着冲击强度的增加尤为敏感。泡沫芯材的压缩和开裂失效使得结构保持良好的完整性和更低的损伤程度,有效地降低了其他组分的能量吸收比,表明泡沫填充有效地提升了复合材料点阵梁结构在局部冲击载荷作用下的防护效能。

Based on the Hashin 3D failure criteria,both stiffness degradation and interface delamination are adopted to model the damage evolution of the composites,a numerical study on the composite lattice sandwich and its foam-reinforce sandwich beams subjected to local impulsive load is performed to identify the effects of impulsive intensity and foam reinforcement on the dynamic response,failure modes,and energy absorption mechanisms.The numerical result is confirmed to have a great agreement with the previously experimental results.The results show the impact strength has a significant influence on the dynamic response,failure mode,and energy dissipation mechanisms of the beams.With the reinforcement of the foam,the composite sandwich beam undergoes a slower deformed response than the lattice sandwich beam,especially for the intensive loads.The compression and cracking of the foam core reduces the degree of failure and keeps the structural integrity,and at the same time effectively decreases the energy absorption ratio of other components,indicating a noticeable improvement of impact resistance of the foam-reinforce composite lattice sandwich beam to concentrated impact load.