Dead metal cap plays an important role in the microcutting process because target material piled up on the tool–chip–udworkpiece interface can alter the cutting geometry. The target of this study is to model and simulate the microorthogonaludcutting process in the presence of dead metal cap in order to investigate the effects of this phenomenon onudthe micromachining process outputs (cutting force, thrust force and chip thickness) and stress distribution, equivalentudplastic strain and temperature inside the workpiece shear zones. For this purpose, the finite element method with explicituddynamic solution and adiabatic heating effect along with arbitrary Lagrangian–Eulerian approach is used. It is shownudthat the finite element models with current state-of-the-art assumptions cannot take into account the dead metal cap byuddefault. For this reason, dead metal cap is artificially introduced on the rounded tool edge in this study for carrying out audproper analysis. Several simulations with different dead metal cap geometries are performed and obtained results showudthat prediction of cutting force, thrust force and chip thickness are sensitive to the presence of dead metal cap and itsudgeometry. Micro-orthogonal cutting experiments are carried out on tubular AISI 1045 workpieces for validating andudinterpreting simulated results. The error between predicted and experimental data is calculated, and it is shown thatudsimulation performances can be improved by considering the dead metal cap into the process model. For example, it isudpossible to reduce the error to less than 5% in case of thrust force prediction. This study points out how the targetudmaterial’s Von Mises stress, equivalent plastic strain and temperature distribution are sensitive to any alteration of theudedge geometry due to the dead metal cap. The best dead metal cap configuration in terms of agreement with experimentsudis also the one introducing a more homogeneous distribution of these quantities along the shear plane.
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