Influence of Punch Servo Path on Elliptical Hole Flange Forming

Abstract

This study investigated the process of forming an elliptical hole flange by using a SPFC780Y high-strength steel sheet with a material thickness of 1 mm. Three servo motion paths on a servo press were compared with a traditional crank motion path on a conventional press. Four punch motion paths were analyzed, namely a crank motion path on a conventional press (type T), a servo motion path with a 3-mm downward motion followed by a 0.5-mm upward motion (type S3), a servo motion path with a 2-mm downward motion followed by a 0.5-mm upward motion (type S2), and a servo motion path with a 1-mm downward motion followed by a 0.5-mm upward motion (type S1). The finished products of an elliptical hole flanging process were evaluated in terms of thickness, force-displacement, stress, strain, and springback. The results reveal that the products produced using the evaluated servo motion paths were superior to those produced using the evaluated crank motion path.