Understanding of the fundamentals of metal cutting processes through the experimental studies has some limitations. Metal cutting modelling provides an alternative way for better understanding of machining processes under different cutting conditions. Using the capabilities of finite element models, it has recently become possible to deal with complicated conditions in metal cutting. Finite element modelling makes it possible to model several factors that are present during the chip formation including friction at the chip tool interface, temperature, stress, strain, and strain rate. The aim of improved understanding of metal cutting is to find ways to have high quality machined surfaces, while minimizing machining time and tooling cost.;The study involves the turning of AISI 4140 steel using a cutting tool made of carbide material. All the material properties are extracted from previously published work, including the Johnson-Cook parameters. The effect of initial chip geometry, feed rate of friction coefficient on cutting forces, stresses, strains, temperature, and formed chip geometry have been studied. Model solutions were obtained by using the commercially available finite element package ABAQUS/Explicit, version 6.7. The model verification is accomplished by comparing the predicted results to published experimental results.;The current study showed that the effect of the initial chip height does not have major effects on the results. The new formulation with no initial chip is shown to give reasonable prediction of cutting force, feed force and chip thickness. To date all simulations underestimate the chip contact length.;Friction behaviour at the chip-tool interface is one of the complicated subjects in metal cutting that still needs a lot of work. Several models have been presented in the past with different assumptions. In the current model, the Coulomb friction model, which assumes a constant friction coefficient, is used to model the friction in order to simplify the model. The effect ofthe constant friction model is considered by analyzing the results for several friction coefficient values and comparing them to the previous work. The comparison illustrates some weak points in this model that need to have more study.;In this study, an Arbitrary Lagrangian Eulerian (ALE) finite element formulation is used to simulate the continuous chip formation process in orthogonal cutting. The ALE is an effective way to simulate the chip formation as it reduces element distortion that causes several numerical problems. Several ALE models are available in the open literature. Using an ALE approach one needs to understand the various options in order to reach the best results. The combination of Lagrangian and Eulerian formulations has been utilized in the current model to achieve the benefits of both formulations.
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