A novel simulation model of three-dimensional surface topography for five-axis CNC milling using bull-nose tool

Computer numerical control milling is a widely used method for machining free-form workpieces. Studies show that the surface topography of the workpiece has a significant correlation with its mechanical strength and dimensional accuracy. Furthermore, the surface topography is influenced by cutting parameters. The bull-nose tool, which adapts to curvature, is an affecting parameter in improving machining quality. In the present study, a novel three-dimensional surface topography simulation model was proposed. The model employs approximate surfaces to characterize the scallop, enabling analytical calculation of endpoints and boundaries for each scallop without the need to discretize the workpiece into 2D planes or an x–y grid. Subsequently, machining experiments were performed to validate the proposed simulation model. The results revealed that the proposed model could be used to effectively simulate surface topography and predict surface roughness. Finally, the effect of cutting parameters on surface topography and surface roughness was analyzed using the simulation model. And the recommendations were proposed for the selection of these cutting parameters. The developed model exhibits promising potential in engineering applications.