Experimental determination of springback characteristics in a three-point bending test of the aluminium alloy sheet with aluminium cladding

The springback phenomenon that occurs during cold forming is the main problem that affects the dimensional accuracy of bent products. This article presents the results of the analysis of the springback phenomenon occurring during a three-point air bending of 0.5 mm, 0.8 mm, 1.0 mm and 2.0 mm thick AW-2024 aluminium alloy sheet, AW-1050A aluminium clad. For sheets with a thickness of 1.0 mm and 2.0 mm, the influence of heat treatment and natural ageing time of sheets on the value of the springback coefficient was also tested. The springback characteristics were determined by defining the dependence of the springback coefficient on the bending deflection of the band. The experimental results obtained indicate a linear dependence of the value of the springback coefficient on the relative deflection w/fg index (w – distance between supports, fg – deflection under load), both in the case of the influence of the sheet thickness and the ageing time of the sheets.