Enhancing the borosilicate glass micromachining by using mixed alkaline electrolytes in the ECDM process

This article investigates the effects of mixing different alkaline electrolytes on the geometrical features created by the ECDM. Sodium hydroxide (NaOH) and potassium hydroxide (KOH) were mixed in varying volumetric proportions. Effect of critical process parameters on the depth and width of the microchannels and the associated tool wear was investigated. Pure NaOH electrolyte has resulted in the highest depth compared to the pure KOH electrolyte. Process mechanism behind the role of mixed electrolytes on the opening sizes and depths of microchannels is explained. Higher material removal by the NaOH electrolyte was due to the larger number of sodium (Na+) ions in the electrolyte, resulting in more aggressive electrochemical discharge; however, it also resulted in severe tool wear. Mixed electrolytes with a KOH yielded lower width and low tool wear. Increasing the volumetric proportion of KOH in the mixed electrolyte gradually decreased the machining depth, width, and tool wear.