大厚径碳纤维复合材料三维钻削有限元仿真及试验研究

Finite element simulation of and experimental study on three-dimensional drilling of large diameter carbon fiber composites

针对CR929远程宽体客机承力构件制孔出口分层缺陷预测难、制孔载荷预测试验成本高等问题,开展大孔径碳纤维增强树脂基复合材料(CFRP)三维钻削仿真及试验研究。首先基于ABAQUS用户自定义子程序接口,利用Fortran语言编写CFRP宏观力学本构模型;随后建立大孔径CFRP三维钻削仿真过程有限元模型,并验证其正确性;最后利用有限元模型预测不同加工参数下的制孔轴向力、扭矩及出口分层损伤。研究结果表明:基于三维实体单元建模的复合材料,三维钻削有限元仿真模型可以可靠地预测制孔过程中的轴向力、扭矩。在CFRP出口处嵌入黏结单元可以预测制孔出口分层的形状。在相同工艺参数条件下,制孔的轴向力、扭矩、出口分层的仿真预测与试验结果最大相对误差分别为15.0%、19.0%、12.4%。

Aiming at some problems in manufacturing the aircraft CR929,namely difficulty to predict exit delamination defect and high cost of hole load prediction test,a three-dimensional finite element drilling simulation and experimental research of carbon fiber reinforced plastics(CFRP)were carried out.Firstly,the macro-mechanical constitutive model of CFRP was established by Fortran language based on user-defined subroutine interface of ABAQUS software.Then a three-dimensional finite element model of large aperture drilling CFRP was established.By comparing the model in experiment,the correctness of the finite element model is verified under the same parameters.Finally,the finite element model was used to predict the axial force,torque and exit delamination of the hole at different processing parameters.The results show that the three-dimensional finite element simulation model of composite drilling based on three-dimensional solid element modeling can reliably predict the axial force and torque.The shape of exit delamination can be predicted by embedding cohesive elements at the exit of CFRP.Under the same parameters,the maximum relative error of simulation prediction for axial force,torque and exit delamination is 15.0%,19.0%and 12.4%,respectively.