Controllable electrochemical discharge machining with energy–electricity regulation in glycol-based electrolytes

Abstract

Electrochemical discharge machining (ECDM) is widely used for manufacturing owing to its ability to machine any material regardless of its properties. Insufficient knowledge regarding the gas film and process mechanism restricts further improvement of electrochemical discharge machining (ECDM). In this study, to control the machining process, ECDM was performed using glycol-based electrolytes and a novel energy–electricity regulation methodology was developed. Through the analysis of gas film quality and machining performance, the advantages of glycol-based electrolytes were verified and a material removal model was established. Subsequently, analyzes of electrical signals based on the experimental verification of multiple process parameters were presented to realize the quantitative regulation of electrical discharge machining (EDM) and electrochemical machining (ECM) in ECDM. The results indicated that in glycol-based electrolytes, the gas film is thin and stable, and there is no transpassive film on the workpiece. Therefore, the material removal process was enhanced with regard to effectiveness and uniformity, and the surface integrity was improved. Furthermore, by adjusting the EDM energy (E) to approximately 10n–14n μJ (where n represents the total pulse number) and ECM electricity (Q) to approximately 0.5n–1n μC, low wire relative wear ratio and small slit width can be achieved. Pentagram patterns were successfully fabricated on several typical metallic materials, which verified the universality of the proposed process.