Numerical modelling of orthogonal cutting: influence of numerical parameters

The study of material local removal phenomena is relevant in all machining problems. Despite many studies, which have largely increased our understanding of this process, the constant evolution of metallurgical, chemical, mechanical and structural characteristics of materials has shown the need to extend investigations in the field of chip formation. Nevertheless, the complexity of the phenomena, met within this framework, often limits the approaches to a configuration known as “orthogonal cutting”. Experimental and analytical methods developed for these studies, have recently been completed by numerical approaches using the finite element method. The aim of this paper is to focus on some numerical problems related to finite element method, and propose some solutions to deal with. In particular the influence of mesh density and hourglass is studied. It is shown that the choice of consistent parameters to validate numerical models is of primary importance to be able to compare experimental and numerical results. The mesh density is shown to be the most influencing parameter in orthogonal cutting modelling and particularly on chip morphology. In contrast, macroscopic parameters, as cutting forces, or internal fields, as stress, strain or temperature, are shown to be less dependent on the mesh size.