The grinding process is one of the most important and widely used machining processes to achieve the desired surface quality and dimensional accuracy. Due to the stochastic nature of the grinding process and process conditions, the instantaneous micro-mechanisms between each grain and the workpiece are momentarily changing and are different from the other grains. Thus, the resultant normal and tangential grinding forces could be obtained by making the vector superposition of the instantaneous forces resulting from the contact of each grain and the workpiece. Previous studies in grinding forces have largely ignored the effects of micro-mechanisms of grain-workpiece in the grinding forces. On the other hand, most of these models are performed to predict grinding forces in the dry state that only can predict the maximal grinding forces based on the maximal value of undeformed chip thickness. In this research, a comprehensive model was used to analyze and predict the grinding forces both under dry conditions and in the presence of grinding fluid. In this research, the instantaneous undeformed chip thickness was calculated by a new method to determine the grinding forces at better accuracy. The proposed model can predict the components of normal and tangential grinding forces (including sliding, plowing, and cutting) based on the instantaneous undeformed chip thickness resulting from the kinematic analysis of abrasive grain trajectory and micro-mechanisms of cutting between abrasive grain and workpiece. By this method, the grinding forces were calculated more accurately than previous analytical models. In addition, a 2D slip line model was employed to separate dry and lubricated stages along with friction coefficient estimation for every single grain instantaneously. By this approach, the normal and tangential grinding forces could be predictable without the need for constant coefficients and additional experimental tests in both dry and lubricated stages. According to the proposed method, the effects of grinding parameters on each component of grinding forces were analyzed in both dry and lubricated grinding. The proposed model can also increase the accuracy of modeling in other grinding situations such as wheel loading issue, surface topography analysis, heat analysis, and specific grinding energy. In the end, experimental tests were performed to validate the theoretical model. Graphic abstract: [Figure not available: see fulltext.] © 2021, The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.
