Development of Sharp Flanging Technology for Aluminum Panels

摘要

New process of flanging has been developed based upon the idea of redistributing plastic strains through the larger area, delivering additional metal into the bending zone and creating an additional axial compression. The process can be performed in two steps. At the first step, the metal is flanged conventionally with the larger radius of the die. In our experiments with 0.93mm 6111-T4 aluminum sheet, we used the first step radius of 2.5 mm. At the second step we applied a horizontal load, which can be produced using cams. Numerical simulation of flanging processes was conducted using the research code based upon solid elements and explicit integration procedure . The contact interaction between the blank and the die was simulated based upon mild contact approach. The results of numerical simulation explain the mechanism of flanging for both conventional and suggested process. Comparison of the newly developed and conventional flanging process indicated that the new process expands bendability of aluminum alloy 6111-T4 allowing additional prestrain of the panel in previous forming operations. The advantages of the new flanging operation can be transferred to hemming operation.