Unsuitable surface quality is frequently observed in the machining of composites due to their heterogeneity and anisotropic properties. Thus, minimizing the machining damages requires a thorough understanding of the machining process. In this study, two different finite element models were developed using Abaqus/Explicit to simulate the cutting process of unidirectional carbon fiber-reinforced polymer: (i) a macromechanical model based on the homogenization approach and (ii) a micromechanical model in which the composite constituents were treated separately. The effects of CFRP mechanical properties, the energy of breaking and hourglass control were analyzed using a macromechanical model. The results revealed that CFRP properties and the numerical parameters highly influenced the cutting process. A comparative study was also performed between the macromechanical and the micromechanical models to study the mechanisms of chip formation. It was demonstrated that the material removal mechanisms for both models are in good agreement with the experimental observations for different fiber orientation angles.

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Drilling is the most widely used machining process in manufacturing holes in many industrial applications. Optimizing the drilling process is a key to improve the hole quality. Therefore, numerical modeling is an effective method that gives an idea about the cutting process to optimize the drilling parameters. This paper emphasizes the sensitivity of the thrust force, the torque and the machining-induced damage to the hole saw tool geometry using a 3D Finite Element (FE) model developed using ABAQUS/Explicit. A Johnson cook model associated with a ductile damage law is used to predict the failure mechanism of a random chopped glass fiber reinforced polyester. It is found that the thrust force, the torque and the damage around the hole obtained from the FE model are in good agreement with the experimental data. Differences of about 2% for the thrust force, 2.4% for the torque and 3% for the damage around the hole are observed. The results of the numerical model also indicated that the thrust force as well as the drilled workpiece quality are improved by choosing the suitable rake angle. A decrease of about 61% in the thrust force is observed when varying the rake angle from 0° to 20°. However, the latter has an insignificant effect on the thrust force. Furthermore, it can be concluded that this parameter highly influences the material removal process.

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