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

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.