Chip control is a major research issue which is becoming increasingly important. This is because in order to have metal removal processes become more environmentally friendly, the dependence on cutting fluids must be reduced or eliminated. Since cutting fluids are used to flush the chips away from the cutting zone, it will be difficult to remove them in every application without first being able to predict the direction, velocity and morphology of the generated chips. This should be possible with turning and milling processes, but may not ever be possible with grinding, where the cutting fluid is used to flush away very small chips and to lubricate the wheel/work interface.
Finite element models have been developed for the machining process [Strenkowski, Xie, Zhang & Bagchi, etc.], but no model is yet able to be successfully used as an all purpose tool to predict all relevant outputs from a given set of real inputs. Chip curl and breakage, tool erosion and vibration all present major challenges for the modeler.