Atomized-electrolyte jet electrochemical grinding for high-precision green machining of hard-to-machine alloys

Electrochemical Grinding (ECG) is considered a promising high-performance hybrid precision machining process that combines electrochemical dissolution with mechanical grinding. However, its practical applications for hard-to-machine alloys used in aerospace engineering, such as titanium alloys, are hindered by poor machining accuracy. In this study, a modified ECG method, termed Atomized-Electrolyte Jet Electrochemical Grinding (AEJ-ECG), is proposed, and a high-speed atomized-electrolyte jet is initially employed in ECG. Numerical simulations revealed that a localized, high-level, and uniformly distributed current density predominantly governed the material removal process in AEJ-ECG. This contrasts with the broad, highly non-uniform current distribution in the conventional ECG. The experimental results on titanium alloys further corroborate the hypothesis that the concentrated high-energy field characteristics of AEJ-ECG are critical factors contributing to an 87.3 % reduction in surface roughness and a 91.1 % enhancement in machining accuracy compared to conventional ECG. Notably, AEJ-ECG attains these enhancements with less than 5 % of the electrolyte and approximately 49.3 % of the energy required by the conventional ECG. A high-integrity planar surface (Ra 0.7 μm) was obtained with a single finishing-stage feed, resulting in an 89.5 % decrease in grinding wheel wear compared to mechanical grinding. AEJ-ECG exhibits considerable promise for green precision grinding of hard-to-machine alloys in aerospace engineering.