Theoretical Determination of Forming Limit Diagram for Al 2024 T3 sheet when changing strain paths

Abstract

The effect of changing strain paths on forming limit curve of aluminum alloy Al 2024T3 sheet has been studied by determining forming limit diagrams after prestraining theoretically . The method of calculating the shape of forming limit diagrams used Hosford yield criterion (high exponent) with the Marciniak and Kuczynski (M-K) analysis to include the effects of changing the strain path to several levels in (uniaxial, biaxial, and plane strain tension).In this work it was found that theoretical forming limit curve, calculated using the above analysis and yield function is closed to the experimental curve of complex strain path. Keywords : sheet metal forming, forming limit diagram(FLD), complex strain path