复合材料层合板低速冲击损伤与剩余强度分析

Low-velocity Impact Damage and Residual Strength Analysis of Composite Laminates

直升机设计制造过程中,复合材料结构占比较大,因此必须考虑复合材料的低速冲击损伤。通过ABAQUS建立复合材料层合板的有限元模型,并通过VUMAT子程序利用渐进损伤模型及内聚力COHOSIVE单元进行冲击损伤数值分析,得到复合材料层合板层内损伤规律及分层损伤情况。层合板层内损伤与分层损伤发展规律并不一致:层内损伤区域呈现椭圆形,椭圆形的长半轴与该层铺层方向时一致;而分层损伤区域沿着层合板宽度方向扩散。随着冲击能量的递增,压缩极限逐渐下降,且其下降速率逐渐减小。通过试验数据对有限元仿真结果进行验证,该有限元模型能够有效地对该类型复合材料层合板冲击损伤行为进行模拟,能够更好地获得剩余强度不随冲击能量变化的门槛值。

Composite structures account for a large proportion in the design and manufacture of helicopters,so low-velocity impact damage of composite materials must be considered.The finite element model of the composite laminate was established by ABAQUS,and the progressive damage model and the cohesive force COHOSIVE element were used to carry out numerical analysis of impact damage through the VUMAT subprogram,and the damage law and delamination damage of the composite laminate were obtained.The development law of intra-layer damage and delamination damage in laminates was not consistent.The intra-layer damage area presented an ellipse,and the major semi-axis of the ellipse was consistent with the layup direction of the layer,while the delamination damage area spread along the width direction of the laminate.With the increasing impact energy,the compression limit decreased gradually,and its decreasing rate decreased gradually.In addition,the finite element simulation results were verified by the experimental data.The finite element model could effectively simulate the impact damage behavior of this type of composite material laminate,and could better obtain the threshold value of residual strength that did not change with impact energy.