Formability analysis of aluminum double-layer sheets using a magnetorheological fluid

Abstract

Bulging with overlapping metal sheet is one of the important ways to improve the forming performance of light alloy sheet. In order to investigate the bulging performance of aluminium double-layer sheets, this paper uses intelligent materials magnetorheological fluid (MRF) as a force medium for the first time, and also develops a exclusive device structure for it. The results show that: With the increase of magnetic field strength or mass fraction of MRF, the bulging limit of the inner layer aluminium sheets is significantly increased when the double-layer sheets reach the bulging limit, and the size of the location where the cracking length occurs produces an inverse trend change. As the mass fraction of the magnetron fluid increases from 56% to 80% with 3A field coil current, the ultimate wall thickness variation rate of the inner layer aluminium sheet decreases by 15.75%, and bulging limit height increases by 8.74%. It can be seen that with stronger magnetic field or higher mass fraction of the MRF, it improves the uniformity of deformation coordination at various parts of the sheet. This study provides a scientific basis for improving the forming performance and comprehensive quality of low-plastic lightweight sheet. Keywords: Double-layer sheets, Aluminium, Magnetorheological fluid (MRF), Formability