Ping Liu’s scientific contributions

The focus of this paper is to explore the effects of different failure criteria, including Tsai-Wu, Hashin, Chang-Chang and micromechanics of failure criterion, on the dynamic progressive failure properties of carbon fiber reinforced polymers (CFRPs) in drilling. First, a unified finite element (FE) formulation on the dynamic intra-laminar damage and inter-laminar delamination of laminates was developed. Then, the intra-laminar damage model using four failure criteria were implemented by the explicit FE subroutine ABAQUS/VUMAT. Meanwhile, the delamination is simulated by the developed bilinear cohesive elements (CEs) model with mixed-mode failure criterion. Finally, numerical analysis and experiments were performed on drilling T700S-12K/YP-H26 CFRPs laminates to compare the predicted thrust force, torque and the visualized damage phenomenon. Results show that the prediction accuracy of the thrust force and torque is significantly improved. The actual damage behaviors which appear the tearing at the entry, pits of hole-wall’s surface, burrs and interlayer delamination at the exit are simulated when adopts the scale-span modeling method. In contrast, it is required to take more slightly simulation time under the same condition. This research provides fundamental support for appropriate selection and use of different failure criteria to achieve high-efficiency and high-fidelity simulation in the drilling of composites.