Study The Effect Of Curvature On Spring Back Of Double Curved Steel Sheet Using New Method

Spring back is one of main reason for inaccuracy of sheet press formed product. Therefore; prediction of spring back is very important for production of precise products. To calculate the amount of spring back many successful attempts have been done, but unfortunately; most of them belong to the simple cases such as single curved U or V, bending of sheet metals. In this study, an improved yield criterion proposed by Yoshida, have been incorporated in a new formulation for prediction of the spring back in a double curved sheet metal. This criterion is capable to reveal the influence of transient Baushinger effect and work hardening stagnation on spring back analysis. Finally; the effect of some geometrical parameters such as thickness, and curvatures radius will be discussed