Research on springback characteristic and prediction accuracy control of advanced high strength steel

With the progress of automobiles lightening, there has been an increasing demand for high strength steel in automobile manufacturing. Under such situation that the springback is lager and the prediction accuracy is lower, deep researches on the springback characteristic, prediction accuracy and simulation error control of advanced high strength steel have been carried out by means of numerical simulation and experiment. The influences of material parameters and process variables on the bending springback of typical U-shaped parts are analyzed. Springback simulation error function (SSEF) has been established to characterize the springback prediction accuracy. Effects of material hardening model, element size, the number of integration points in the direction of plate thickness and virtual punch velocity on springback prediction accuracy in finite element numerical simulation are discussed. The cause of numerical simulation error is analyzed. Combined with Reverse Engineering techniques, springback simulation accuracy has been improved by the multidimensional error control solution of simulation parameters adjustment, keywords modification and simulation process optimization.