Numerical prediction of the thrust force responsible of delamination during the drilling of the long-fibre composite structures

In this paper, a numerical FE analysis is proposed to calculate the thrust forces responsible for the defect at the exit of the hole during the drilling phase of long-fibre composite structures, within a quasi-static framework. This numerical model – compared with the analytical models studied in the literature – takes into account the tool point geometry as well as the shear force effects in the laminate. The validation of this numerical model is carried out thanks to punching tests conducted at low speed on two types of semi products in carbon/epoxy long fibre manufactured by Hexcel composites. The numerical results provide the right correlation with the experimental values. Moreover, the comparison between the numerical thrust forces and those provided by the analytical models of the literature is called into question.