The simulation of the manufacturing process is increasingly demanded by industry due to its ability to improve the quality of final products and avoid costly prototyping. This investigation develops an advanced numerical approach for modeling bulk materials deformation obtained through shearing. The study aims to predict the evolution of stress states in workpieces. This provides critical insights for designing defect-mitigation strategies through targeted material characterization. The proposed methodology is based on a coupled thermo-mechanical analysis incorporating Johnson-Cook constitutive models for plasticity and damage modeling. A parametric study is conducted to investigate the shear zone, followed by three-dimensional cutting simulation that quantitatively assesses the influence of shearing induced defects on final geometry quality.