Force modeling of micro-grinding incorporating crystallographic effects

Micro-grinding with small-scale grinding wheels is a micro-machining process in precision manufacturing of miniature part features such as those in micro sensors and micro actuators. Modeling of micro-grinding is necessary to understand the effects of process conditions, micro-grinding wheel properties, and material microstructure on the integrity of the parts produced, thereby allowing for process planning, optimization, and control. In this paper, a predictive model for the micro-grinding process was developed by combined consideration of mechanical and thermal effects within a single grit interaction model at the microscale level of material removal while the size effect of micro-machining was incorporated. To assess the thermal effects, a heat transfer model based on the moving heat source analysis is integrated into the developed model. This model quantitatively predicts micro-grinding forces based on micro-grinding wheel topography and material properties including crystallographic effects. Experimental testing in a micro-grinding configuration has been pursued to validate the predictive model by comparing measurements to analytical calculations in the context of orthogonal micro-grinding forces. The analytical model is seen to capture the main trend of the experimental results, while smaller deviations were found over larger depths of cut range.