Force modeling of microscale grinding process incorporating thermal effects

Grinding at the microscale is an essential process in view of its competitive edge over other processes in the fabrication of micro-sized features and parts. The quality of the parts produced by the microscale grinding process can be influenced by various factors related to the mechanical forces induced. Therefore, the predictive modeling of microscale grinding in the context of forces is useful to provide guidance for further development and optimization of this process. In this study, a new model to address mechanical and thermal interactions between the workpiece and an individual single grit on a microscale grinding wheel was developed. This developed model integrates the ploughing and associated friction effects and a moving heat source on the micro-grinding zone under given machining conditions to estimate the thermal effect in microscale grinding process. The ratio of heat partition into the workpiece in the thermal model was also experimentally calibrated using embedded thermocouple measurement followed by analytical calculations. This model quantitatively predicts microscale grinding forces incorporating material properties as functions of strain, strain rate, and temperature. In order to verify this developed model, the experiments based on a surface microscale grinding setup were performed for changing depths of cut. In addition to this, the sensitivity analysis of this model behavior was conducted to identify main effective factors. A comparison between the experiment data and predictions shows that the force model captures the main trend of the microscale grinding physics within the computed range of parameters.