| In this study, surface grinding with diamond wheels has been undertaken on thermally sprayed nanostructured WC/12Co coatings under various grinding conditions. The relationship between grinding force and grinding parameters such as depth of cut, wheel speed and federate is studied.A model for predicting static normal grinding force is constructed . In the model the equivalent depth of cut is used as a basic parameter. A dynamic model is also proppsed for predicting normal grinding force, since grinding process is a dynamic process in which the grinding forces vary with grinding process conditions. This thesis is intended to study grinding dynamics for nanostructured WC/12Co coatings. A dynamic model is constructed to model the grinding process and verified by grinding experiments. The ways to suppress the vibration are discussed .It is demonstrated that the normal grit force increases with the equivalent depth of cut, workpiece speed. The abrasive grits of the grinding wheel and the tribological interactions of bond/chip/workpiece surface in the grinding zone both have an effect on the grinding force. Under certain grinding conditions ductile flow is dominant for nanostructured ceramic WC/12-Co coatings.When thermally sprayed nanostructured WC/12Co coatings is machined in surface grinding with diamond wheels, the wheel regenerative effect is the dominant factor. The wheel dressing, cutting stiffness, wear coefficient of grinding wheel , grinder stiffness and system damping coefficient have effects on the dynamical normal grinding force. Under certain condition the vibration can be suppressed .The model is presented in time domain which can accommodate nonlinearities typically associated with the grinding process. Through both theoretical modeling and experimental investigations, the study concludes that the dynamic model can be used to predict grinding force.The conclusions can provide theoretical basis on the precision grinding process of nanostructured ceramic coatings.
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