Investigation on electrolyte jet machining of three-dimensional freeform surfaces

The increasing demand for optimized component surfaces with enhanced tribological, optical, chemical, biomedical, and geometric complexity is a key driver in the development of electrolyte jet machining (EJM) technology. To date the applications of EJM method have been limited to planar surface processing. Realization of three-dimensional freeform surfaces with high precision by EJM is of significant importance to advance the process. In this study, the characteristics and principle of multi-axis EJM of arbitrary-shaped workpieces were investigated for the first time. The resultant machined features were experimentally demonstrated under principal factors of inter-electrode gap distance, jet orientation relative to workpiece surface, jet orientation relative to gravity, and workpiece configuration. Furthermore, a simulation model of EJM considering jet orientation and workpiece curvature was built to analyze the electrolyte jet flow and clarify the principle of the current density distribution in the non-symmetric electrolyte flow. It is demonstrated that jet orientations directly affect the profiles of current density distribution and consequently result in varied machining results. In EJM of freeform surfaces, a smaller radius of curvature brings about more intensive concentration of current density distribution and consequently a larger machining depth. The same principles are confirmed in EJM of corner shapes with different angles.