NUMERICAL SIMULATION AND EXPERIMENTAL VALIDATION OF HYDROFORMING OF SQUARE CUPS USING CRYOROLLED ALUMINUM ALLOY SHEETS

摘要

Application of aluminum alloys in automotive industry has significantly increased due to their high strength to weight ratio. However, their absolute strength and formability are inferior when compared to traditional steels. Severe plastic deformation processes such as cryorolling are used widely to enhance the strength but they result in poor formability. Through hydroforming, it is possible to enhance formability of Al alloys. Numerical simulations have been carried out to predict formability of cryogenically rolled AA5083 aluminum alloy sheets of 1mm thickness. Deep drawing of square cups by hydroforming from these sheets was simulated using FEA. By varying fluid pressure and blank holding force, strain distribution, thinning and corner radius have been predicted. A good correlation with experimental results has been obtained. It has been shown that it is possible to achieve a suitable combination of high strength and formability in Al alloy deep drawn parts by combining cryorolling and hydroforming.