Improving Formability of Low-Carbon Steel Shells through Deep Drawing: Experimental Analysis using SPSS

Abstract

Deep drawing, a prevalent sheet metal forming technique, is beset by fracture, wrinkling, and earing. This research investigates punch velocity, die curvature, and lubrication to enhance the formability of low-carbon steel cups. These parameters were selected due to their direct influence on forming force, metal flow, and thickness distribution, which dictate product quality. This study examines the impact of speed, radius, and lubrication on formability. The pressure of the blank holder and the height of the die can also influence formability. Experiments designed by DOE approach were assessed using SPSS and validated by Bootstrapping. Speed was the primary element influencing forming force and thickness; however, die radius and lubrication had a greater impact on force. Utilizing lubrication (oil or grease) at a rate of 200 mm/min with a die radius of 6–8 mm diminished thinning and friction relative to dry conditions, producing optimal outcomes. The regression models demonstrated R² values of 64.3% for force and 78.7% for thickness, so confirming their validity. A thorough experimental validation demonstrates that in typical deep drawing of low-carbon steel, speed is the predominant factor, while lubrication enhances surface quality. This research enhances traditional deep drawing through statistically validated models, offering novel guidelines to augment manufacturing efficiency and product reliability. Prior research concentrated on blank-holder pressure or sophisticated shaping methodologies.