Investigation on parameters which affect on springback and side wall curl of U-bending of dual-phase steel plates

The most prominent feature of sheet material forming process is an elastic recovery phenomenon during unloading which leads to springback and side wall curl. Therefore evaluation of springback and side wall curl is mandatory for production of precise products. In this paper، the effects of some parameters such as friction coefficient، sheet thickness، yield strength of sheet and blank-holder force on the springback and side wall curl radius in U-bending of dual phase steel sheets were investigated by performing experimental tests and finite element method. ABAQUS software was used for finite element simulation. Comparison of experimental and finite element results shows good agreement. The results of this research shows that increasing of sheet thickness، reduces springback and side wall curl and increasing of yield strength increases springback and side wall curl. Springback and side wall curl initially increase with raising the friction coefficient and blank-holder force but they decrease again when they go beyond certain values.