Material removal mechanism of variable-section cutting for nickel-based superalloy honeycomb composites

The nickel-based superalloy honeycomb composite (NBSHC), characterized by its ultra-high specific strength, specific stiffness, and high temperature resistance, finds application in cutting-edge technological fields such as aerospace and military industries. The primary machining features of superalloy honeycombs include variable-section and constant-section. However, when processing variable-section features, defects such as burrs, tears, deformation, and collapse are extremely prone to occur. To investigate the mechanism of variable-section machining (VSM) on the superalloy honeycomb, a finite element method (FEM) model for variable-section cutting of superalloy honeycomb with a disc cutter is established, simulating the material removal process during VSM. From a microscopic perspective of VSM of superalloy honeycomb, a multiple consecutive cutting model is developed with different inclination angles of the cutting edge, revealing the defect formation mechanism. Based on the comprehensive results of experiments and simulations, the mapping rules between different inclination angles and VSM defects were explored, and the influence of multiple consecutive cuts on defect formation was clarified. The results indicate that as the inclination angle of the variable cross-section increases, the angle between the normal vector of the tool's shear plane and the normal vector of the honeycomb wall also increases, resulting in an enlarged shear area. This leads to severe honeycomb deformation and deterioration of machining defects.