Micro milling force prediction of arc thin-walled parts considering dual flexibility coupling deformation

Abstract

Abstract The prediction of micro milling forces in difficult-to-machine materials such as titanium alloys, which have small dimensions and arc-thin-walled features, has become a major challenge due to the coupling effect of multi-physics fields. This problem has become a key bottleneck in the development of aerospace, space, biomedical and other fields. To address this issue, this study focuses on titanium alloy arc-thin-walled parts and develops a micro milling force prediction model that considers the dual flexible coupling deformation and geometric features of arc-thin-walled parts in the process of micro milling. Firstly, a micro milling force theoretical model is established based on the instantaneous cutter position angle and the actual instantaneous uncut thickness. Secondly, detailed geometric analysis is conducted to calculate the entry and exit angles and instantaneous uncut thickness considering the characteristics of arc micro milling paths. Subsequently, the Euler beam and Timoshenko beam are assumed based on the characteristics of the cutter and workpiece structure, as well as the force situations. The unit stiffness matrix is then solved to calculate the deflection deformation value. An iterative algorithm is used to introduce the coupling deflection deformation into the micro milling force prediction model, thereby improving the instantaneous uncut thickness model. Finally, the micro milling force data is obtained through arc micro milling experiments and the coefficient of micro milling force is identified. The micro milling force is predicted using a theoretical model and its rationality and accuracy is verified through experiments. The proposed model and methodology have practical significance and provide a basis for optimizing micro milling processes and promoting the development of related fields.