RETRACTED: Micro-macro-mechanical model and material removal mechanism of machining carbon fiber reinforced polymer

Abstract

Abstract The present paper studies the material removal mechanism of machining carbon fiber reinforced polymer (CFRP) by a micro-mechanical model, and proposes prediction models of cutting forces from the microscale to the macroscale. At the microscale, the micro-mechanical model for cutting a fiber in orthogonal cutting CFRP is established via the elastic foundation beam theory with explicit description of the carbon fiber and the matrix. The deflection and failure of the fiber constrained by the surrounding composite are analyzed under the cutting effects by the tool edge. In addition, the fiber failure under the pressing of the flank face is analyzed based on the undulating fiber theory. Analytical expressions are established at the microscale for evaluating the force for cutting a single fiber and the compression force for a single fiber from the flank face. At the macroscale, the chip length is determined by analyzing the characteristics of the cutting force signals of orthogonal cutting experiments. The characteristic chip length is used for establishing the trans-scale prediction model of cutting forces from the microscale to the macroscale. The total cutting and thrust forces at the macroscale during the formation of a chip are predicted based on the micro-mechanical results and the characteristic chip length, which agree well with the experimental results for orthogonal cutting of CFRP. Furthermore, the fiber failure modes and the debonding between the fiber and the matrix under different supporting conditions are discussed by the micro-mechanical model, by which subsurface damages are recognized.