Micro- and macro-scale simulation for axial cutting machining behaviors of 2D tri-axially braided composites

Abstract

The cutting machining process of 2D tri-axially braided composite (2DTBC) is very complex, which presents a significant challenge to the industry. To understand the cutting mechanisms to improve the processing quality, the cutting behaviors of 2DTBC are predicted using multi-scale simulation. The micro-scale model is proposed to capture damage modes of fibers, matrix and interface using a fracture energy method. The anisotropic macro-scale model based on nonlinear degradation method is adopted. To obtain macro-scale material properties, the cross-scale material calculation is conducted at micro- and meso‑scale. Then, the micro-scale cutting responses of fiber tow with main fiber orientations in 2DTBC are simulated. The macro-scale cutting responses of 2DTBC are also predicted. The micro deformation patterns and cutting force for different fiber orientations are revealed and correlate well with available experiment results. It is found that the damage depth of matrix and interface increases with the decrease of fiber orientation. The matrix is prone to fracture for acute angles. Based on macro-scale chip formation process, it is revealed that the chip formation mainly experiences material damaging, squeezing, sliding and shedding.