Optimization of electrohydraulic forming process parameters using the response surface methodology

• Published in: Materialprüfung Vol. 63; no. 6; pp. 571 - 580
• Main Authors: Arun Prasath, Balasubramanian, Ganesh, Pasupathy, Shanmuga Sundaram, Karibeeran
• Format: Journal Article
• Language: English
• Published: De Gruyter 30.06.2021
• Subjects: Electrohydraulic forming; macro-micro shape; RSM; stainless steel
• ISSN: 0025-5300; 2195-8572
• DOI: 10.1515/mt-2020-0096

This work’s main objective is to determine the optimum process parameters in the electrohydraulic forming (EHF) of austenitic stainless steel AISI 304 of 0.25 mm thickness for macro and micro shape. A truncated cone with grooves in the apex is considered as macro-micro shape. The response surface methodology (RSM) was developed for process variables such as voltage and standoff distance to determine the optimum parameters. To validate the model, confirmation experiments have been conducted, i. e. for the optimum value of voltage (V) = 8.935 kV and standoff distance (SOD) = 40.60 mm, and from the experiments the forming depth predicted is 9.221 mm and depth from the experiments is 9.5 mm. The percentage deviation from the predicted and experimental forming depth is 3.025 %, an acceptable range of less than 5 % for the surface roughness, the predicted value is 0.2598 microns, and the experimentally measured value is 0.268. The percentage deviation is 3.156 % between the predicted and experimental values, an acceptable range of less than 5 %. This shows that the model is suitable for predicting both responses. The validation experiments also found that the sheet fills one of the grooves and partially fills the other, which shows the capability of the electrohydraulic forming process. Confirmation experiments have been conducted.