Aluminum Springback Reduction by Post-forming Electric Pulses

Abstract

The use of aluminum alloy has been increasing in the automotive industry in the last years where a clear example is the new platforms of Jaguar Land Rover. On that regard, manufacturing problems such as galling, die wear and high springback have become critical for the stamping industry. Among them, the post-forming elastic recovery of the aluminum (with a third of elastic modulus compared to the steels) has become a big concern for the automotive stamping tool makers. Since the early 60s, the effect of electrical pulses on the dislocation movement has been studied as a mean of reducing stresses/forces necessary for the forming. In addition, this reduction leads to lower subsequent springback. However, the application of this technology during the forming is a big challenge that numerous researchers have been working to solve. In this work, the impact of the high speed short electrical pulses in the post-forming step (close die) is studied and the obtained springback reduction analyzed.