In sheet metal forming industries, finite element simulations are commonly used for the process/tool design. An important factor for finite element modeling is mechanical property (flow stress curves and stress–strain relationships) of the sheet material. Hydroforming bulge and uniaxial tensile tests were performed on four different sheet metal alloys of industrial interest and the resulting flow stress curves determined using different analytical approaches developed by Hill, Panknin, Chakrabarty and Kruglov. To obtain flow stress curves, both the dome height and pressure were measured during the bulge tests. The effect of anisotropy and strain hardening characteristics were also investigated. The results show that biaxial loading provides flow stress properties at higher strain levels as compared to uniaxial loading. It was also concluded that an accurate flow curves can be obtained using Panknin’s bulge radius and Kruglov’s thickness calculation approaches.
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