Establishment of CFRP drilling simulation model considering heat accumulation effect and study on its delamination damage

Abstract

Abstract The low damage and high quality hole making technology of carbon fiber reinforced polymer/plastic (CFRP) components has been the main problem restricting its rapid popularization. In this paper, taking the delamination defect at the exit of CFRP drilling as the research object, a three-dimensional simulation model of CFRP drilling considering heat accumulation effect is established. The validity of the model is verified by comparing the experimental data of CFRP boreholes from three dimensions: the distribution of surface temperature field at the borehole outlet, the drilling axial force, and the delamination factor at the outlet. The accuracy of the model is verified by comparing with the simulation results of normal temperature CFRP 3D drilling without considering the heat accumulation effect. Furthermore, the model was used to analyze the variation of the temperature field and delamination damage at the outlet of the CFRP hole during the drilling process. It is found that the delamination damage at the exit of the unsupported dry drilling of CFRP is formed at the stage from the horizontal edge of the drill bit just reaching the exit plane of the drilling hole to half of the length of the main cutting edge of the drill bit leaving the workpiece. Finally, the model was used to study the variation of axial force and export delamination factor under different processing parameters, and the quantitative relationship between processing parameters and export delamination factor was obtained by multiple regression. It is pointed out that the processing parameters should be reasonably selected to reduce the delamination damage of CFRP drilling. In addition, it is important to take appropriate measures to conduct sufficient heat conduction and reduce heat accumulation at the stage of delamination damage formation at the exit.