Full-Tooth Conformal Electrochemical Machining of High-Precision Gears: via Reverse Flow Field Control

The gears are the core fundamental components of mechanical transmission systems, and their manufacturing quality directly determines the performance of equipment. However, traditional machining is prone to introducing residual stress and thermal damage, while electrochemical machining (ECM) for complex gear structures faces a prominent contradiction between stray corrosion and cathode structural strength, which restricts the coordinated improvement of gear dimensional precision and surface integrity. Reducing cathode thickness can mitigate current concentration effects, thereby suppressing sidewall stray corrosion at the source. To address this issue, this paper innovatively proposes a reverse flow full-tooth conformal ECM method. Through precise flow field design to actively regulate the stress state of the cathode, the proposed method achieves a 57% reduction in cathode thickness compared with the minimum thickness of the forward flow configuration, enhances cathode stability, and resolves the key challenges of thin-cathode instability and stray corrosion. Experimental results demonstrate that the method significantly improves gear accuracy and surface integrity, the deviations of the addendum circle and dedendum circle diameters are reduced by 81% and 93%, respectively, the tooth thickness deviation decreases by 91%, the sidewall taper is lowered by 3°, and the machined surface achieves excellent near-zero residual stress. This study provides a novel strategy for decoupling process contradictions via fluid control in high-precision and efficient ECM of precision gears.