Experimental analysis and quality optimization of honeycomb seal structures processed via grinding-assisted electrochemical discharge machining

Metal honeycomb seal rings are widely used in aerospace field due to their excellent sealing performance. Electrochemical discharge machining (ECDM) can be used to process honeycomb seal structures, but the molten products restrict machining efficiency and surface quality. Therefore, in order to improve the machining quality, this study proposes the use of Grinding-assisted ECDM (G-ECDM) for the manufacturing of honeycomb seal structures through theoretical and experimental investigations. By analyzing the molten product formation and G-ECDM mechanism, it was found that the abrasive effect height should exceed the molten product height, so the selection of abrasive effect height was 40 μm. The energy distribution proportions (EDPs) were obtained by measuring the electric and grinding force signals to characterize the relationship between the machining parameters and energy forms. The experimental results were used to analyze the influence of different EDPs on the results, including surface morphology, cross-sectional morphology, excessive corrosion depth, single-wall thinning width, and material removal rate. Moreover, a Gaussian process regression model of EDPs was established to optimize the machining parameters, and excellent results were obtained at 16 V, 1 wt%, 57 mm/min. The results prove that G-ECDM is suitable for the high-quality manufacturing of honeycomb seal structures.