A theoretical model for predicting the CFRP drilling-countersinking thrust force of stacks

Abstract

Thrust force is a remarkable intermediate variable in the drilling-countersinking process of carbon fiber reinforced plastic (CFRP) and aluminum (Al) stacks. Because of the poor machinability and extreme abrasiveness of CFRP, tool wear cannot be neglected. Focusing on the CFRP drilling and countersinking thrust force of stacks, this paper provided a novel insight into the modeling of the influence of tool wear on thrust force through both experiments and theoretical analysis. The experimental exploration is first presented in this study, and the flank wear was observed and it is the primary abrasion type. Then a method of infinitesimal elements with substitution has been used to develop the theoretical model of thrust force based on the mathematical abstraction of flank wear size and morphology, and the forces of the deformation region under the wear land in the element are the increscent component which contributes a lot to the variation of the total thrust force. Finally the theoretical model is verified by the multivariate experiments, and the results show that proposed model can work well. The work in this paper enables us to understand the influence of flank wear on thrust forces through the fundamental insight of CFRP cutting process.