An improved numerical model for prediction of residual plastic strain in machining of Ti6Al4V titanium alloy concerning cutting edge microgeometries

The influence of tool cutting edge (TCE) microgeometry on machined surface integrity remains inadequately understood. This study aims to shed some light on this by developing an enhanced numerical model to capture the plastic deformation induced by the TCE radius during the machining of Ti6Al4V titanium alloy. The model employs Finite Element (FE) simulations using a Lagrangian approach without sacrificial layers (LAG-nSL) and integrates a robust constitutive material model through a custom subroutine. Experimental validation is conducted by comparing residual plastic strain (RPS) distributions beneath the machined surface, obtained via the digital image correlation (DIC) technique and FE simulation results. The findings demonstrate satisfactory agreement in most cases. The depth of the layer affected by RPS ranges from around 90 to 130 μm, with deeper layers observed at larger TCE radii, higher cutting speeds, and smaller tool rake angles.