A noval stress integration algorithm in inverse analysis method of sheet metal stamping

An improved inverse analysis method is proposed for sheetmetal stamping based on the final workpiece in Euler coordinate system. Theprinciple of the virtual work is firstly adopted to obtain the equivalentequations. The constitutive equation in the present method is based on flowtheory of plasticity to consider the loading history, while deformationtheory of plasticity in the classical inverse analysis method. The plasticmultiplier \Delta \lambda is directly obtained with the concept ofthe equivalent stress in order to avoid numerous iterations inNewton-Raphson scheme \Delta \lambda. The numerical resultsobtained from the classical and improved inverse analysis methods arecompared with those from the incremental forward finite element solverLS-DYNA. It shows that the proposed constitutive equation is effective andreliable with the comparisons of blank configurations, Forming LimitedDiagram (FLD), the effective strain distribution and computationalefficiency.